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authorJuan Linietsky <reduzio@gmail.com>2017-01-21 19:00:25 -0300
committerJuan Linietsky <reduzio@gmail.com>2017-01-21 19:01:00 -0300
commit0aa7242624fcd74eaf13db006274829c284fab3b (patch)
tree85ae8bc9d725f191da68f1b9ffe1e426025e8fb2 /thirdparty/stb_vorbis/stb_vorbis.c
parentc4d6e54e93431e94888c5594386bcd0aa22528ee (diff)
WIP new AudioServer, with buses, effects, etc.
Diffstat (limited to 'thirdparty/stb_vorbis/stb_vorbis.c')
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+// Ogg Vorbis audio decoder - v1.09 - public domain
+// http://nothings.org/stb_vorbis/
+//
+// Original version written by Sean Barrett in 2007.
+//
+// Originally sponsored by RAD Game Tools. Seeking sponsored
+// by Phillip Bennefall, Marc Andersen, Aaron Baker, Elias Software,
+// Aras Pranckevicius, and Sean Barrett.
+//
+// LICENSE
+//
+// This software is dual-licensed to the public domain and under the following
+// license: you are granted a perpetual, irrevocable license to copy, modify,
+// publish, and distribute this file as you see fit.
+//
+// No warranty for any purpose is expressed or implied by the author (nor
+// by RAD Game Tools). Report bugs and send enhancements to the author.
+//
+// Limitations:
+//
+// - floor 0 not supported (used in old ogg vorbis files pre-2004)
+// - lossless sample-truncation at beginning ignored
+// - cannot concatenate multiple vorbis streams
+// - sample positions are 32-bit, limiting seekable 192Khz
+// files to around 6 hours (Ogg supports 64-bit)
+//
+// Feature contributors:
+// Dougall Johnson (sample-exact seeking)
+//
+// Bugfix/warning contributors:
+// Terje Mathisen Niklas Frykholm Andy Hill
+// Casey Muratori John Bolton Gargaj
+// Laurent Gomila Marc LeBlanc Ronny Chevalier
+// Bernhard Wodo Evan Balster alxprd@github
+// Tom Beaumont Ingo Leitgeb Nicolas Guillemot
+// Phillip Bennefall Rohit Thiago Goulart
+// manxorist@github saga musix
+//
+// Partial history:
+// 1.09 - 2016/04/04 - back out 'truncation of last frame' fix from previous version
+// 1.08 - 2016/04/02 - warnings; setup memory leaks; truncation of last frame
+// 1.07 - 2015/01/16 - fixes for crashes on invalid files; warning fixes; const
+// 1.06 - 2015/08/31 - full, correct support for seeking API (Dougall Johnson)
+// some crash fixes when out of memory or with corrupt files
+// fix some inappropriately signed shifts
+// 1.05 - 2015/04/19 - don't define __forceinline if it's redundant
+// 1.04 - 2014/08/27 - fix missing const-correct case in API
+// 1.03 - 2014/08/07 - warning fixes
+// 1.02 - 2014/07/09 - declare qsort comparison as explicitly _cdecl in Windows
+// 1.01 - 2014/06/18 - fix stb_vorbis_get_samples_float (interleaved was correct)
+// 1.0 - 2014/05/26 - fix memory leaks; fix warnings; fix bugs in >2-channel;
+// (API change) report sample rate for decode-full-file funcs
+//
+// See end of file for full version history.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// HEADER BEGINS HERE
+//
+
+#ifndef STB_VORBIS_INCLUDE_STB_VORBIS_H
+#define STB_VORBIS_INCLUDE_STB_VORBIS_H
+
+#if defined(STB_VORBIS_NO_CRT) && !defined(STB_VORBIS_NO_STDIO)
+#define STB_VORBIS_NO_STDIO 1
+#endif
+
+#ifndef STB_VORBIS_NO_STDIO
+#include <stdio.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/////////// THREAD SAFETY
+
+// Individual stb_vorbis* handles are not thread-safe; you cannot decode from
+// them from multiple threads at the same time. However, you can have multiple
+// stb_vorbis* handles and decode from them independently in multiple thrads.
+
+
+/////////// MEMORY ALLOCATION
+
+// normally stb_vorbis uses malloc() to allocate memory at startup,
+// and alloca() to allocate temporary memory during a frame on the
+// stack. (Memory consumption will depend on the amount of setup
+// data in the file and how you set the compile flags for speed
+// vs. size. In my test files the maximal-size usage is ~150KB.)
+//
+// You can modify the wrapper functions in the source (setup_malloc,
+// setup_temp_malloc, temp_malloc) to change this behavior, or you
+// can use a simpler allocation model: you pass in a buffer from
+// which stb_vorbis will allocate _all_ its memory (including the
+// temp memory). "open" may fail with a VORBIS_outofmem if you
+// do not pass in enough data; there is no way to determine how
+// much you do need except to succeed (at which point you can
+// query get_info to find the exact amount required. yes I know
+// this is lame).
+//
+// If you pass in a non-NULL buffer of the type below, allocation
+// will occur from it as described above. Otherwise just pass NULL
+// to use malloc()/alloca()
+
+typedef struct
+{
+ char *alloc_buffer;
+ int alloc_buffer_length_in_bytes;
+} stb_vorbis_alloc;
+
+
+/////////// FUNCTIONS USEABLE WITH ALL INPUT MODES
+
+typedef struct stb_vorbis stb_vorbis;
+
+typedef struct
+{
+ unsigned int sample_rate;
+ int channels;
+
+ unsigned int setup_memory_required;
+ unsigned int setup_temp_memory_required;
+ unsigned int temp_memory_required;
+
+ int max_frame_size;
+} stb_vorbis_info;
+
+// get general information about the file
+extern stb_vorbis_info stb_vorbis_get_info(stb_vorbis *f);
+
+// get the last error detected (clears it, too)
+extern int stb_vorbis_get_error(stb_vorbis *f);
+
+// close an ogg vorbis file and free all memory in use
+extern void stb_vorbis_close(stb_vorbis *f);
+
+// this function returns the offset (in samples) from the beginning of the
+// file that will be returned by the next decode, if it is known, or -1
+// otherwise. after a flush_pushdata() call, this may take a while before
+// it becomes valid again.
+// NOT WORKING YET after a seek with PULLDATA API
+extern int stb_vorbis_get_sample_offset(stb_vorbis *f);
+
+// returns the current seek point within the file, or offset from the beginning
+// of the memory buffer. In pushdata mode it returns 0.
+extern unsigned int stb_vorbis_get_file_offset(stb_vorbis *f);
+
+/////////// PUSHDATA API
+
+#ifndef STB_VORBIS_NO_PUSHDATA_API
+
+// this API allows you to get blocks of data from any source and hand
+// them to stb_vorbis. you have to buffer them; stb_vorbis will tell
+// you how much it used, and you have to give it the rest next time;
+// and stb_vorbis may not have enough data to work with and you will
+// need to give it the same data again PLUS more. Note that the Vorbis
+// specification does not bound the size of an individual frame.
+
+extern stb_vorbis *stb_vorbis_open_pushdata(
+ const unsigned char * datablock, int datablock_length_in_bytes,
+ int *datablock_memory_consumed_in_bytes,
+ int *error,
+ const stb_vorbis_alloc *alloc_buffer);
+// create a vorbis decoder by passing in the initial data block containing
+// the ogg&vorbis headers (you don't need to do parse them, just provide
+// the first N bytes of the file--you're told if it's not enough, see below)
+// on success, returns an stb_vorbis *, does not set error, returns the amount of
+// data parsed/consumed on this call in *datablock_memory_consumed_in_bytes;
+// on failure, returns NULL on error and sets *error, does not change *datablock_memory_consumed
+// if returns NULL and *error is VORBIS_need_more_data, then the input block was
+// incomplete and you need to pass in a larger block from the start of the file
+
+extern int stb_vorbis_decode_frame_pushdata(
+ stb_vorbis *f,
+ const unsigned char *datablock, int datablock_length_in_bytes,
+ int *channels, // place to write number of float * buffers
+ float ***output, // place to write float ** array of float * buffers
+ int *samples // place to write number of output samples
+ );
+// decode a frame of audio sample data if possible from the passed-in data block
+//
+// return value: number of bytes we used from datablock
+//
+// possible cases:
+// 0 bytes used, 0 samples output (need more data)
+// N bytes used, 0 samples output (resynching the stream, keep going)
+// N bytes used, M samples output (one frame of data)
+// note that after opening a file, you will ALWAYS get one N-bytes,0-sample
+// frame, because Vorbis always "discards" the first frame.
+//
+// Note that on resynch, stb_vorbis will rarely consume all of the buffer,
+// instead only datablock_length_in_bytes-3 or less. This is because it wants
+// to avoid missing parts of a page header if they cross a datablock boundary,
+// without writing state-machiney code to record a partial detection.
+//
+// The number of channels returned are stored in *channels (which can be
+// NULL--it is always the same as the number of channels reported by
+// get_info). *output will contain an array of float* buffers, one per
+// channel. In other words, (*output)[0][0] contains the first sample from
+// the first channel, and (*output)[1][0] contains the first sample from
+// the second channel.
+
+extern void stb_vorbis_flush_pushdata(stb_vorbis *f);
+// inform stb_vorbis that your next datablock will not be contiguous with
+// previous ones (e.g. you've seeked in the data); future attempts to decode
+// frames will cause stb_vorbis to resynchronize (as noted above), and
+// once it sees a valid Ogg page (typically 4-8KB, as large as 64KB), it
+// will begin decoding the _next_ frame.
+//
+// if you want to seek using pushdata, you need to seek in your file, then
+// call stb_vorbis_flush_pushdata(), then start calling decoding, then once
+// decoding is returning you data, call stb_vorbis_get_sample_offset, and
+// if you don't like the result, seek your file again and repeat.
+#endif
+
+
+////////// PULLING INPUT API
+
+#ifndef STB_VORBIS_NO_PULLDATA_API
+// This API assumes stb_vorbis is allowed to pull data from a source--
+// either a block of memory containing the _entire_ vorbis stream, or a
+// FILE * that you or it create, or possibly some other reading mechanism
+// if you go modify the source to replace the FILE * case with some kind
+// of callback to your code. (But if you don't support seeking, you may
+// just want to go ahead and use pushdata.)
+
+#if !defined(STB_VORBIS_NO_STDIO) && !defined(STB_VORBIS_NO_INTEGER_CONVERSION)
+extern int stb_vorbis_decode_filename(const char *filename, int *channels, int *sample_rate, short **output);
+#endif
+#if !defined(STB_VORBIS_NO_INTEGER_CONVERSION)
+extern int stb_vorbis_decode_memory(const unsigned char *mem, int len, int *channels, int *sample_rate, short **output);
+#endif
+// decode an entire file and output the data interleaved into a malloc()ed
+// buffer stored in *output. The return value is the number of samples
+// decoded, or -1 if the file could not be opened or was not an ogg vorbis file.
+// When you're done with it, just free() the pointer returned in *output.
+
+extern stb_vorbis * stb_vorbis_open_memory(const unsigned char *data, int len,
+ int *error, const stb_vorbis_alloc *alloc_buffer);
+// create an ogg vorbis decoder from an ogg vorbis stream in memory (note
+// this must be the entire stream!). on failure, returns NULL and sets *error
+
+#ifndef STB_VORBIS_NO_STDIO
+extern stb_vorbis * stb_vorbis_open_filename(const char *filename,
+ int *error, const stb_vorbis_alloc *alloc_buffer);
+// create an ogg vorbis decoder from a filename via fopen(). on failure,
+// returns NULL and sets *error (possibly to VORBIS_file_open_failure).
+
+extern stb_vorbis * stb_vorbis_open_file(FILE *f, int close_handle_on_close,
+ int *error, const stb_vorbis_alloc *alloc_buffer);
+// create an ogg vorbis decoder from an open FILE *, looking for a stream at
+// the _current_ seek point (ftell). on failure, returns NULL and sets *error.
+// note that stb_vorbis must "own" this stream; if you seek it in between
+// calls to stb_vorbis, it will become confused. Morever, if you attempt to
+// perform stb_vorbis_seek_*() operations on this file, it will assume it
+// owns the _entire_ rest of the file after the start point. Use the next
+// function, stb_vorbis_open_file_section(), to limit it.
+
+extern stb_vorbis * stb_vorbis_open_file_section(FILE *f, int close_handle_on_close,
+ int *error, const stb_vorbis_alloc *alloc_buffer, unsigned int len);
+// create an ogg vorbis decoder from an open FILE *, looking for a stream at
+// the _current_ seek point (ftell); the stream will be of length 'len' bytes.
+// on failure, returns NULL and sets *error. note that stb_vorbis must "own"
+// this stream; if you seek it in between calls to stb_vorbis, it will become
+// confused.
+#endif
+
+extern int stb_vorbis_seek_frame(stb_vorbis *f, unsigned int sample_number);
+extern int stb_vorbis_seek(stb_vorbis *f, unsigned int sample_number);
+// these functions seek in the Vorbis file to (approximately) 'sample_number'.
+// after calling seek_frame(), the next call to get_frame_*() will include
+// the specified sample. after calling stb_vorbis_seek(), the next call to
+// stb_vorbis_get_samples_* will start with the specified sample. If you
+// do not need to seek to EXACTLY the target sample when using get_samples_*,
+// you can also use seek_frame().
+
+extern void stb_vorbis_seek_start(stb_vorbis *f);
+// this function is equivalent to stb_vorbis_seek(f,0)
+
+extern unsigned int stb_vorbis_stream_length_in_samples(stb_vorbis *f);
+extern float stb_vorbis_stream_length_in_seconds(stb_vorbis *f);
+// these functions return the total length of the vorbis stream
+
+extern int stb_vorbis_get_frame_float(stb_vorbis *f, int *channels, float ***output);
+// decode the next frame and return the number of samples. the number of
+// channels returned are stored in *channels (which can be NULL--it is always
+// the same as the number of channels reported by get_info). *output will
+// contain an array of float* buffers, one per channel. These outputs will
+// be overwritten on the next call to stb_vorbis_get_frame_*.
+//
+// You generally should not intermix calls to stb_vorbis_get_frame_*()
+// and stb_vorbis_get_samples_*(), since the latter calls the former.
+
+#ifndef STB_VORBIS_NO_INTEGER_CONVERSION
+extern int stb_vorbis_get_frame_short_interleaved(stb_vorbis *f, int num_c, short *buffer, int num_shorts);
+extern int stb_vorbis_get_frame_short (stb_vorbis *f, int num_c, short **buffer, int num_samples);
+#endif
+// decode the next frame and return the number of *samples* per channel.
+// Note that for interleaved data, you pass in the number of shorts (the
+// size of your array), but the return value is the number of samples per
+// channel, not the total number of samples.
+//
+// The data is coerced to the number of channels you request according to the
+// channel coercion rules (see below). You must pass in the size of your
+// buffer(s) so that stb_vorbis will not overwrite the end of the buffer.
+// The maximum buffer size needed can be gotten from get_info(); however,
+// the Vorbis I specification implies an absolute maximum of 4096 samples
+// per channel.
+
+// Channel coercion rules:
+// Let M be the number of channels requested, and N the number of channels present,
+// and Cn be the nth channel; let stereo L be the sum of all L and center channels,
+// and stereo R be the sum of all R and center channels (channel assignment from the
+// vorbis spec).
+// M N output
+// 1 k sum(Ck) for all k
+// 2 * stereo L, stereo R
+// k l k > l, the first l channels, then 0s
+// k l k <= l, the first k channels
+// Note that this is not _good_ surround etc. mixing at all! It's just so
+// you get something useful.
+
+extern int stb_vorbis_get_samples_float_interleaved(stb_vorbis *f, int channels, float *buffer, int num_floats);
+extern int stb_vorbis_get_samples_float(stb_vorbis *f, int channels, float **buffer, int num_samples);
+// gets num_samples samples, not necessarily on a frame boundary--this requires
+// buffering so you have to supply the buffers. DOES NOT APPLY THE COERCION RULES.
+// Returns the number of samples stored per channel; it may be less than requested
+// at the end of the file. If there are no more samples in the file, returns 0.
+
+#ifndef STB_VORBIS_NO_INTEGER_CONVERSION
+extern int stb_vorbis_get_samples_short_interleaved(stb_vorbis *f, int channels, short *buffer, int num_shorts);
+extern int stb_vorbis_get_samples_short(stb_vorbis *f, int channels, short **buffer, int num_samples);
+#endif
+// gets num_samples samples, not necessarily on a frame boundary--this requires
+// buffering so you have to supply the buffers. Applies the coercion rules above
+// to produce 'channels' channels. Returns the number of samples stored per channel;
+// it may be less than requested at the end of the file. If there are no more
+// samples in the file, returns 0.
+
+#endif
+
+//////// ERROR CODES
+
+enum STBVorbisError
+{
+ VORBIS__no_error,
+
+ VORBIS_need_more_data=1, // not a real error
+
+ VORBIS_invalid_api_mixing, // can't mix API modes
+ VORBIS_outofmem, // not enough memory
+ VORBIS_feature_not_supported, // uses floor 0
+ VORBIS_too_many_channels, // STB_VORBIS_MAX_CHANNELS is too small
+ VORBIS_file_open_failure, // fopen() failed
+ VORBIS_seek_without_length, // can't seek in unknown-length file
+
+ VORBIS_unexpected_eof=10, // file is truncated?
+ VORBIS_seek_invalid, // seek past EOF
+
+ // decoding errors (corrupt/invalid stream) -- you probably
+ // don't care about the exact details of these
+
+ // vorbis errors:
+ VORBIS_invalid_setup=20,
+ VORBIS_invalid_stream,
+
+ // ogg errors:
+ VORBIS_missing_capture_pattern=30,
+ VORBIS_invalid_stream_structure_version,
+ VORBIS_continued_packet_flag_invalid,
+ VORBIS_incorrect_stream_serial_number,
+ VORBIS_invalid_first_page,
+ VORBIS_bad_packet_type,
+ VORBIS_cant_find_last_page,
+ VORBIS_seek_failed
+};
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // STB_VORBIS_INCLUDE_STB_VORBIS_H
+//
+// HEADER ENDS HERE
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#ifndef STB_VORBIS_HEADER_ONLY
+
+// global configuration settings (e.g. set these in the project/makefile),
+// or just set them in this file at the top (although ideally the first few
+// should be visible when the header file is compiled too, although it's not
+// crucial)
+
+// STB_VORBIS_NO_PUSHDATA_API
+// does not compile the code for the various stb_vorbis_*_pushdata()
+// functions
+// #define STB_VORBIS_NO_PUSHDATA_API
+
+// STB_VORBIS_NO_PULLDATA_API
+// does not compile the code for the non-pushdata APIs
+// #define STB_VORBIS_NO_PULLDATA_API
+
+// STB_VORBIS_NO_STDIO
+// does not compile the code for the APIs that use FILE *s internally
+// or externally (implied by STB_VORBIS_NO_PULLDATA_API)
+// #define STB_VORBIS_NO_STDIO
+
+// STB_VORBIS_NO_INTEGER_CONVERSION
+// does not compile the code for converting audio sample data from
+// float to integer (implied by STB_VORBIS_NO_PULLDATA_API)
+// #define STB_VORBIS_NO_INTEGER_CONVERSION
+
+// STB_VORBIS_NO_FAST_SCALED_FLOAT
+// does not use a fast float-to-int trick to accelerate float-to-int on
+// most platforms which requires endianness be defined correctly.
+//#define STB_VORBIS_NO_FAST_SCALED_FLOAT
+
+
+// STB_VORBIS_MAX_CHANNELS [number]
+// globally define this to the maximum number of channels you need.
+// The spec does not put a restriction on channels except that
+// the count is stored in a byte, so 255 is the hard limit.
+// Reducing this saves about 16 bytes per value, so using 16 saves
+// (255-16)*16 or around 4KB. Plus anything other memory usage
+// I forgot to account for. Can probably go as low as 8 (7.1 audio),
+// 6 (5.1 audio), or 2 (stereo only).
+#ifndef STB_VORBIS_MAX_CHANNELS
+#define STB_VORBIS_MAX_CHANNELS 16 // enough for anyone?
+#endif
+
+// STB_VORBIS_PUSHDATA_CRC_COUNT [number]
+// after a flush_pushdata(), stb_vorbis begins scanning for the
+// next valid page, without backtracking. when it finds something
+// that looks like a page, it streams through it and verifies its
+// CRC32. Should that validation fail, it keeps scanning. But it's
+// possible that _while_ streaming through to check the CRC32 of
+// one candidate page, it sees another candidate page. This #define
+// determines how many "overlapping" candidate pages it can search
+// at once. Note that "real" pages are typically ~4KB to ~8KB, whereas
+// garbage pages could be as big as 64KB, but probably average ~16KB.
+// So don't hose ourselves by scanning an apparent 64KB page and
+// missing a ton of real ones in the interim; so minimum of 2
+#ifndef STB_VORBIS_PUSHDATA_CRC_COUNT
+#define STB_VORBIS_PUSHDATA_CRC_COUNT 4
+#endif
+
+// STB_VORBIS_FAST_HUFFMAN_LENGTH [number]
+// sets the log size of the huffman-acceleration table. Maximum
+// supported value is 24. with larger numbers, more decodings are O(1),
+// but the table size is larger so worse cache missing, so you'll have
+// to probe (and try multiple ogg vorbis files) to find the sweet spot.
+#ifndef STB_VORBIS_FAST_HUFFMAN_LENGTH
+#define STB_VORBIS_FAST_HUFFMAN_LENGTH 10
+#endif
+
+// STB_VORBIS_FAST_BINARY_LENGTH [number]
+// sets the log size of the binary-search acceleration table. this
+// is used in similar fashion to the fast-huffman size to set initial
+// parameters for the binary search
+
+// STB_VORBIS_FAST_HUFFMAN_INT
+// The fast huffman tables are much more efficient if they can be
+// stored as 16-bit results instead of 32-bit results. This restricts
+// the codebooks to having only 65535 possible outcomes, though.
+// (At least, accelerated by the huffman table.)
+#ifndef STB_VORBIS_FAST_HUFFMAN_INT
+#define STB_VORBIS_FAST_HUFFMAN_SHORT
+#endif
+
+// STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
+// If the 'fast huffman' search doesn't succeed, then stb_vorbis falls
+// back on binary searching for the correct one. This requires storing
+// extra tables with the huffman codes in sorted order. Defining this
+// symbol trades off space for speed by forcing a linear search in the
+// non-fast case, except for "sparse" codebooks.
+// #define STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
+
+// STB_VORBIS_DIVIDES_IN_RESIDUE
+// stb_vorbis precomputes the result of the scalar residue decoding
+// that would otherwise require a divide per chunk. you can trade off
+// space for time by defining this symbol.
+// #define STB_VORBIS_DIVIDES_IN_RESIDUE
+
+// STB_VORBIS_DIVIDES_IN_CODEBOOK
+// vorbis VQ codebooks can be encoded two ways: with every case explicitly
+// stored, or with all elements being chosen from a small range of values,
+// and all values possible in all elements. By default, stb_vorbis expands
+// this latter kind out to look like the former kind for ease of decoding,
+// because otherwise an integer divide-per-vector-element is required to
+// unpack the index. If you define STB_VORBIS_DIVIDES_IN_CODEBOOK, you can
+// trade off storage for speed.
+//#define STB_VORBIS_DIVIDES_IN_CODEBOOK
+
+#ifdef STB_VORBIS_CODEBOOK_SHORTS
+#error "STB_VORBIS_CODEBOOK_SHORTS is no longer supported as it produced incorrect results for some input formats"
+#endif
+
+// STB_VORBIS_DIVIDE_TABLE
+// this replaces small integer divides in the floor decode loop with
+// table lookups. made less than 1% difference, so disabled by default.
+
+// STB_VORBIS_NO_INLINE_DECODE
+// disables the inlining of the scalar codebook fast-huffman decode.
+// might save a little codespace; useful for debugging
+// #define STB_VORBIS_NO_INLINE_DECODE
+
+// STB_VORBIS_NO_DEFER_FLOOR
+// Normally we only decode the floor without synthesizing the actual
+// full curve. We can instead synthesize the curve immediately. This
+// requires more memory and is very likely slower, so I don't think
+// you'd ever want to do it except for debugging.
+// #define STB_VORBIS_NO_DEFER_FLOOR
+
+
+
+
+//////////////////////////////////////////////////////////////////////////////
+
+#ifdef STB_VORBIS_NO_PULLDATA_API
+ #define STB_VORBIS_NO_INTEGER_CONVERSION
+ #define STB_VORBIS_NO_STDIO
+#endif
+
+#if defined(STB_VORBIS_NO_CRT) && !defined(STB_VORBIS_NO_STDIO)
+ #define STB_VORBIS_NO_STDIO 1
+#endif
+
+#ifndef STB_VORBIS_NO_INTEGER_CONVERSION
+#ifndef STB_VORBIS_NO_FAST_SCALED_FLOAT
+
+ // only need endianness for fast-float-to-int, which we don't
+ // use for pushdata
+
+ #ifndef STB_VORBIS_BIG_ENDIAN
+ #define STB_VORBIS_ENDIAN 0
+ #else
+ #define STB_VORBIS_ENDIAN 1
+ #endif
+
+#endif
+#endif
+
+
+#ifndef STB_VORBIS_NO_STDIO
+#include <stdio.h>
+#endif
+
+#ifndef STB_VORBIS_NO_CRT
+ #include <stdlib.h>
+ #include <string.h>
+ #include <assert.h>
+ #include <math.h>
+
+ // find definition of alloca if it's not in stdlib.h:
+ #ifdef _MSC_VER
+ #include <malloc.h>
+ #endif
+ #if defined(__linux__) || defined(__linux) || defined(__EMSCRIPTEN__)
+ #include <alloca.h>
+ #endif
+#else // STB_VORBIS_NO_CRT
+ #define NULL 0
+ #define malloc(s) 0
+ #define free(s) ((void) 0)
+ #define realloc(s) 0
+#endif // STB_VORBIS_NO_CRT
+
+#include <limits.h>
+
+#ifdef __MINGW32__
+ // eff you mingw:
+ // "fixed":
+ // http://sourceforge.net/p/mingw-w64/mailman/message/32882927/
+ // "no that broke the build, reverted, who cares about C":
+ // http://sourceforge.net/p/mingw-w64/mailman/message/32890381/
+ #ifdef __forceinline
+ #undef __forceinline
+ #endif
+ #define __forceinline
+#elif !defined(_MSC_VER)
+ #if __GNUC__
+ #define __forceinline inline
+ #else
+ #define __forceinline
+ #endif
+#endif
+
+#if STB_VORBIS_MAX_CHANNELS > 256
+#error "Value of STB_VORBIS_MAX_CHANNELS outside of allowed range"
+#endif
+
+#if STB_VORBIS_FAST_HUFFMAN_LENGTH > 24
+#error "Value of STB_VORBIS_FAST_HUFFMAN_LENGTH outside of allowed range"
+#endif
+
+
+#if 0
+#include <crtdbg.h>
+#define CHECK(f) _CrtIsValidHeapPointer(f->channel_buffers[1])
+#else
+#define CHECK(f) ((void) 0)
+#endif
+
+#define MAX_BLOCKSIZE_LOG 13 // from specification
+#define MAX_BLOCKSIZE (1 << MAX_BLOCKSIZE_LOG)
+
+
+typedef unsigned char uint8;
+typedef signed char int8;
+typedef unsigned short uint16;
+typedef signed short int16;
+typedef unsigned int uint32;
+typedef signed int int32;
+
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif
+
+typedef float codetype;
+
+// @NOTE
+//
+// Some arrays below are tagged "//varies", which means it's actually
+// a variable-sized piece of data, but rather than malloc I assume it's
+// small enough it's better to just allocate it all together with the
+// main thing
+//
+// Most of the variables are specified with the smallest size I could pack
+// them into. It might give better performance to make them all full-sized
+// integers. It should be safe to freely rearrange the structures or change
+// the sizes larger--nothing relies on silently truncating etc., nor the
+// order of variables.
+
+#define FAST_HUFFMAN_TABLE_SIZE (1 << STB_VORBIS_FAST_HUFFMAN_LENGTH)
+#define FAST_HUFFMAN_TABLE_MASK (FAST_HUFFMAN_TABLE_SIZE - 1)
+
+typedef struct
+{
+ int dimensions, entries;
+ uint8 *codeword_lengths;
+ float minimum_value;
+ float delta_value;
+ uint8 value_bits;
+ uint8 lookup_type;
+ uint8 sequence_p;
+ uint8 sparse;
+ uint32 lookup_values;
+ codetype *multiplicands;
+ uint32 *codewords;
+ #ifdef STB_VORBIS_FAST_HUFFMAN_SHORT
+ int16 fast_huffman[FAST_HUFFMAN_TABLE_SIZE];
+ #else
+ int32 fast_huffman[FAST_HUFFMAN_TABLE_SIZE];
+ #endif
+ uint32 *sorted_codewords;
+ int *sorted_values;
+ int sorted_entries;
+} Codebook;
+
+typedef struct
+{
+ uint8 order;
+ uint16 rate;
+ uint16 bark_map_size;
+ uint8 amplitude_bits;
+ uint8 amplitude_offset;
+ uint8 number_of_books;
+ uint8 book_list[16]; // varies
+} Floor0;
+
+typedef struct
+{
+ uint8 partitions;
+ uint8 partition_class_list[32]; // varies
+ uint8 class_dimensions[16]; // varies
+ uint8 class_subclasses[16]; // varies
+ uint8 class_masterbooks[16]; // varies
+ int16 subclass_books[16][8]; // varies
+ uint16 Xlist[31*8+2]; // varies
+ uint8 sorted_order[31*8+2];
+ uint8 neighbors[31*8+2][2];
+ uint8 floor1_multiplier;
+ uint8 rangebits;
+ int values;
+} Floor1;
+
+typedef union
+{
+ Floor0 floor0;
+ Floor1 floor1;
+} Floor;
+
+typedef struct
+{
+ uint32 begin, end;
+ uint32 part_size;
+ uint8 classifications;
+ uint8 classbook;
+ uint8 **classdata;
+ int16 (*residue_books)[8];
+} Residue;
+
+typedef struct
+{
+ uint8 magnitude;
+ uint8 angle;
+ uint8 mux;
+} MappingChannel;
+
+typedef struct
+{
+ uint16 coupling_steps;
+ MappingChannel *chan;
+ uint8 submaps;
+ uint8 submap_floor[15]; // varies
+ uint8 submap_residue[15]; // varies
+} Mapping;
+
+typedef struct
+{
+ uint8 blockflag;
+ uint8 mapping;
+ uint16 windowtype;
+ uint16 transformtype;
+} Mode;
+
+typedef struct
+{
+ uint32 goal_crc; // expected crc if match
+ int bytes_left; // bytes left in packet
+ uint32 crc_so_far; // running crc
+ int bytes_done; // bytes processed in _current_ chunk
+ uint32 sample_loc; // granule pos encoded in page
+} CRCscan;
+
+typedef struct
+{
+ uint32 page_start, page_end;
+ uint32 last_decoded_sample;
+} ProbedPage;
+
+struct stb_vorbis
+{
+ // user-accessible info
+ unsigned int sample_rate;
+ int channels;
+
+ unsigned int setup_memory_required;
+ unsigned int temp_memory_required;
+ unsigned int setup_temp_memory_required;
+
+ // input config
+#ifndef STB_VORBIS_NO_STDIO
+ FILE *f;
+ uint32 f_start;
+ int close_on_free;
+#endif
+
+ uint8 *stream;
+ uint8 *stream_start;
+ uint8 *stream_end;
+
+ uint32 stream_len;
+
+ uint8 push_mode;
+
+ uint32 first_audio_page_offset;
+
+ ProbedPage p_first, p_last;
+
+ // memory management
+ stb_vorbis_alloc alloc;
+ int setup_offset;
+ int temp_offset;
+
+ // run-time results
+ int eof;
+ enum STBVorbisError error;
+
+ // user-useful data
+
+ // header info
+ int blocksize[2];
+ int blocksize_0, blocksize_1;
+ int codebook_count;
+ Codebook *codebooks;
+ int floor_count;
+ uint16 floor_types[64]; // varies
+ Floor *floor_config;
+ int residue_count;
+ uint16 residue_types[64]; // varies
+ Residue *residue_config;
+ int mapping_count;
+ Mapping *mapping;
+ int mode_count;
+ Mode mode_config[64]; // varies
+
+ uint32 total_samples;
+
+ // decode buffer
+ float *channel_buffers[STB_VORBIS_MAX_CHANNELS];
+ float *outputs [STB_VORBIS_MAX_CHANNELS];
+
+ float *previous_window[STB_VORBIS_MAX_CHANNELS];
+ int previous_length;
+
+ #ifndef STB_VORBIS_NO_DEFER_FLOOR
+ int16 *finalY[STB_VORBIS_MAX_CHANNELS];
+ #else
+ float *floor_buffers[STB_VORBIS_MAX_CHANNELS];
+ #endif
+
+ uint32 current_loc; // sample location of next frame to decode
+ int current_loc_valid;
+
+ // per-blocksize precomputed data
+
+ // twiddle factors
+ float *A[2],*B[2],*C[2];
+ float *window[2];
+ uint16 *bit_reverse[2];
+
+ // current page/packet/segment streaming info
+ uint32 serial; // stream serial number for verification
+ int last_page;
+ int segment_count;
+ uint8 segments[255];
+ uint8 page_flag;
+ uint8 bytes_in_seg;
+ uint8 first_decode;
+ int next_seg;
+ int last_seg; // flag that we're on the last segment
+ int last_seg_which; // what was the segment number of the last seg?
+ uint32 acc;
+ int valid_bits;
+ int packet_bytes;
+ int end_seg_with_known_loc;
+ uint32 known_loc_for_packet;
+ int discard_samples_deferred;
+ uint32 samples_output;
+
+ // push mode scanning
+ int page_crc_tests; // only in push_mode: number of tests active; -1 if not searching
+#ifndef STB_VORBIS_NO_PUSHDATA_API
+ CRCscan scan[STB_VORBIS_PUSHDATA_CRC_COUNT];
+#endif
+
+ // sample-access
+ int channel_buffer_start;
+ int channel_buffer_end;
+};
+
+#if defined(STB_VORBIS_NO_PUSHDATA_API)
+ #define IS_PUSH_MODE(f) FALSE
+#elif defined(STB_VORBIS_NO_PULLDATA_API)
+ #define IS_PUSH_MODE(f) TRUE
+#else
+ #define IS_PUSH_MODE(f) ((f)->push_mode)
+#endif
+
+typedef struct stb_vorbis vorb;
+
+static int error(vorb *f, enum STBVorbisError e)
+{
+ f->error = e;
+ if (!f->eof && e != VORBIS_need_more_data) {
+ f->error=e; // breakpoint for debugging
+ }
+ return 0;
+}
+
+
+// these functions are used for allocating temporary memory
+// while decoding. if you can afford the stack space, use
+// alloca(); otherwise, provide a temp buffer and it will
+// allocate out of those.
+
+#define array_size_required(count,size) (count*(sizeof(void *)+(size)))
+
+#define temp_alloc(f,size) (f->alloc.alloc_buffer ? setup_temp_malloc(f,size) : alloca(size))
+#ifdef dealloca
+#define temp_free(f,p) (f->alloc.alloc_buffer ? 0 : dealloca(size))
+#else
+#define temp_free(f,p) 0
+#endif
+#define temp_alloc_save(f) ((f)->temp_offset)
+#define temp_alloc_restore(f,p) ((f)->temp_offset = (p))
+
+#define temp_block_array(f,count,size) make_block_array(temp_alloc(f,array_size_required(count,size)), count, size)
+
+// given a sufficiently large block of memory, make an array of pointers to subblocks of it
+static void *make_block_array(void *mem, int count, int size)
+{
+ int i;
+ void ** p = (void **) mem;
+ char *q = (char *) (p + count);
+ for (i=0; i < count; ++i) {
+ p[i] = q;
+ q += size;
+ }
+ return p;
+}
+
+static void *setup_malloc(vorb *f, int sz)
+{
+ sz = (sz+3) & ~3;
+ f->setup_memory_required += sz;
+ if (f->alloc.alloc_buffer) {
+ void *p = (char *) f->alloc.alloc_buffer + f->setup_offset;
+ if (f->setup_offset + sz > f->temp_offset) return NULL;
+ f->setup_offset += sz;
+ return p;
+ }
+ return sz ? malloc(sz) : NULL;
+}
+
+static void setup_free(vorb *f, void *p)
+{
+ if (f->alloc.alloc_buffer) return; // do nothing; setup mem is a stack
+ free(p);
+}
+
+static void *setup_temp_malloc(vorb *f, int sz)
+{
+ sz = (sz+3) & ~3;
+ if (f->alloc.alloc_buffer) {
+ if (f->temp_offset - sz < f->setup_offset) return NULL;
+ f->temp_offset -= sz;
+ return (char *) f->alloc.alloc_buffer + f->temp_offset;
+ }
+ return malloc(sz);
+}
+
+static void setup_temp_free(vorb *f, void *p, int sz)
+{
+ if (f->alloc.alloc_buffer) {
+ f->temp_offset += (sz+3)&~3;
+ return;
+ }
+ free(p);
+}
+
+#define CRC32_POLY 0x04c11db7 // from spec
+
+static uint32 crc_table[256];
+static void crc32_init(void)
+{
+ int i,j;
+ uint32 s;
+ for(i=0; i < 256; i++) {
+ for (s=(uint32) i << 24, j=0; j < 8; ++j)
+ s = (s << 1) ^ (s >= (1U<<31) ? CRC32_POLY : 0);
+ crc_table[i] = s;
+ }
+}
+
+static __forceinline uint32 crc32_update(uint32 crc, uint8 byte)
+{
+ return (crc << 8) ^ crc_table[byte ^ (crc >> 24)];
+}
+
+
+// used in setup, and for huffman that doesn't go fast path
+static unsigned int bit_reverse(unsigned int n)
+{
+ n = ((n & 0xAAAAAAAA) >> 1) | ((n & 0x55555555) << 1);
+ n = ((n & 0xCCCCCCCC) >> 2) | ((n & 0x33333333) << 2);
+ n = ((n & 0xF0F0F0F0) >> 4) | ((n & 0x0F0F0F0F) << 4);
+ n = ((n & 0xFF00FF00) >> 8) | ((n & 0x00FF00FF) << 8);
+ return (n >> 16) | (n << 16);
+}
+
+static float square(float x)
+{
+ return x*x;
+}
+
+// this is a weird definition of log2() for which log2(1) = 1, log2(2) = 2, log2(4) = 3
+// as required by the specification. fast(?) implementation from stb.h
+// @OPTIMIZE: called multiple times per-packet with "constants"; move to setup
+static int ilog(int32 n)
+{
+ static signed char log2_4[16] = { 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4 };
+
+ // 2 compares if n < 16, 3 compares otherwise (4 if signed or n > 1<<29)
+ if (n < (1 << 14))
+ if (n < (1 << 4)) return 0 + log2_4[n ];
+ else if (n < (1 << 9)) return 5 + log2_4[n >> 5];
+ else return 10 + log2_4[n >> 10];
+ else if (n < (1 << 24))
+ if (n < (1 << 19)) return 15 + log2_4[n >> 15];
+ else return 20 + log2_4[n >> 20];
+ else if (n < (1 << 29)) return 25 + log2_4[n >> 25];
+ else if (n < (1 << 31)) return 30 + log2_4[n >> 30];
+ else return 0; // signed n returns 0
+}
+
+#ifndef M_PI
+ #define M_PI 3.14159265358979323846264f // from CRC
+#endif
+
+// code length assigned to a value with no huffman encoding
+#define NO_CODE 255
+
+/////////////////////// LEAF SETUP FUNCTIONS //////////////////////////
+//
+// these functions are only called at setup, and only a few times
+// per file
+
+static float float32_unpack(uint32 x)
+{
+ // from the specification
+ uint32 mantissa = x & 0x1fffff;
+ uint32 sign = x & 0x80000000;
+ uint32 exp = (x & 0x7fe00000) >> 21;
+ double res = sign ? -(double)mantissa : (double)mantissa;
+ return (float) ldexp((float)res, exp-788);
+}
+
+
+// zlib & jpeg huffman tables assume that the output symbols
+// can either be arbitrarily arranged, or have monotonically
+// increasing frequencies--they rely on the lengths being sorted;
+// this makes for a very simple generation algorithm.
+// vorbis allows a huffman table with non-sorted lengths. This
+// requires a more sophisticated construction, since symbols in
+// order do not map to huffman codes "in order".
+static void add_entry(Codebook *c, uint32 huff_code, int symbol, int count, int len, uint32 *values)
+{
+ if (!c->sparse) {
+ c->codewords [symbol] = huff_code;
+ } else {
+ c->codewords [count] = huff_code;
+ c->codeword_lengths[count] = len;
+ values [count] = symbol;
+ }
+}
+
+static int compute_codewords(Codebook *c, uint8 *len, int n, uint32 *values)
+{
+ int i,k,m=0;
+ uint32 available[32];
+
+ memset(available, 0, sizeof(available));
+ // find the first entry
+ for (k=0; k < n; ++k) if (len[k] < NO_CODE) break;
+ if (k == n) { assert(c->sorted_entries == 0); return TRUE; }
+ // add to the list
+ add_entry(c, 0, k, m++, len[k], values);
+ // add all available leaves
+ for (i=1; i <= len[k]; ++i)
+ available[i] = 1U << (32-i);
+ // note that the above code treats the first case specially,
+ // but it's really the same as the following code, so they
+ // could probably be combined (except the initial code is 0,
+ // and I use 0 in available[] to mean 'empty')
+ for (i=k+1; i < n; ++i) {
+ uint32 res;
+ int z = len[i], y;
+ if (z == NO_CODE) continue;
+ // find lowest available leaf (should always be earliest,
+ // which is what the specification calls for)
+ // note that this property, and the fact we can never have
+ // more than one free leaf at a given level, isn't totally
+ // trivial to prove, but it seems true and the assert never
+ // fires, so!
+ while (z > 0 && !available[z]) --z;
+ if (z == 0) { return FALSE; }
+ res = available[z];
+ assert(z >= 0 && z < 32);
+ available[z] = 0;
+ add_entry(c, bit_reverse(res), i, m++, len[i], values);
+ // propogate availability up the tree
+ if (z != len[i]) {
+ assert(len[i] >= 0 && len[i] < 32);
+ for (y=len[i]; y > z; --y) {
+ assert(available[y] == 0);
+ available[y] = res + (1 << (32-y));
+ }
+ }
+ }
+ return TRUE;
+}
+
+// accelerated huffman table allows fast O(1) match of all symbols
+// of length <= STB_VORBIS_FAST_HUFFMAN_LENGTH
+static void compute_accelerated_huffman(Codebook *c)
+{
+ int i, len;
+ for (i=0; i < FAST_HUFFMAN_TABLE_SIZE; ++i)
+ c->fast_huffman[i] = -1;
+
+ len = c->sparse ? c->sorted_entries : c->entries;
+ #ifdef STB_VORBIS_FAST_HUFFMAN_SHORT
+ if (len > 32767) len = 32767; // largest possible value we can encode!
+ #endif
+ for (i=0; i < len; ++i) {
+ if (c->codeword_lengths[i] <= STB_VORBIS_FAST_HUFFMAN_LENGTH) {
+ uint32 z = c->sparse ? bit_reverse(c->sorted_codewords[i]) : c->codewords[i];
+ // set table entries for all bit combinations in the higher bits
+ while (z < FAST_HUFFMAN_TABLE_SIZE) {
+ c->fast_huffman[z] = i;
+ z += 1 << c->codeword_lengths[i];
+ }
+ }
+ }
+}
+
+#ifdef _MSC_VER
+#define STBV_CDECL __cdecl
+#else
+#define STBV_CDECL
+#endif
+
+static int STBV_CDECL uint32_compare(const void *p, const void *q)
+{
+ uint32 x = * (uint32 *) p;
+ uint32 y = * (uint32 *) q;
+ return x < y ? -1 : x > y;
+}
+
+static int include_in_sort(Codebook *c, uint8 len)
+{
+ if (c->sparse) { assert(len != NO_CODE); return TRUE; }
+ if (len == NO_CODE) return FALSE;
+ if (len > STB_VORBIS_FAST_HUFFMAN_LENGTH) return TRUE;
+ return FALSE;
+}
+
+// if the fast table above doesn't work, we want to binary
+// search them... need to reverse the bits
+static void compute_sorted_huffman(Codebook *c, uint8 *lengths, uint32 *values)
+{
+ int i, len;
+ // build a list of all the entries
+ // OPTIMIZATION: don't include the short ones, since they'll be caught by FAST_HUFFMAN.
+ // this is kind of a frivolous optimization--I don't see any performance improvement,
+ // but it's like 4 extra lines of code, so.
+ if (!c->sparse) {
+ int k = 0;
+ for (i=0; i < c->entries; ++i)
+ if (include_in_sort(c, lengths[i]))
+ c->sorted_codewords[k++] = bit_reverse(c->codewords[i]);
+ assert(k == c->sorted_entries);
+ } else {
+ for (i=0; i < c->sorted_entries; ++i)
+ c->sorted_codewords[i] = bit_reverse(c->codewords[i]);
+ }
+
+ qsort(c->sorted_codewords, c->sorted_entries, sizeof(c->sorted_codewords[0]), uint32_compare);
+ c->sorted_codewords[c->sorted_entries] = 0xffffffff;
+
+ len = c->sparse ? c->sorted_entries : c->entries;
+ // now we need to indicate how they correspond; we could either
+ // #1: sort a different data structure that says who they correspond to
+ // #2: for each sorted entry, search the original list to find who corresponds
+ // #3: for each original entry, find the sorted entry
+ // #1 requires extra storage, #2 is slow, #3 can use binary search!
+ for (i=0; i < len; ++i) {
+ int huff_len = c->sparse ? lengths[values[i]] : lengths[i];
+ if (include_in_sort(c,huff_len)) {
+ uint32 code = bit_reverse(c->codewords[i]);
+ int x=0, n=c->sorted_entries;
+ while (n > 1) {
+ // invariant: sc[x] <= code < sc[x+n]
+ int m = x + (n >> 1);
+ if (c->sorted_codewords[m] <= code) {
+ x = m;
+ n -= (n>>1);
+ } else {
+ n >>= 1;
+ }
+ }
+ assert(c->sorted_codewords[x] == code);
+ if (c->sparse) {
+ c->sorted_values[x] = values[i];
+ c->codeword_lengths[x] = huff_len;
+ } else {
+ c->sorted_values[x] = i;
+ }
+ }
+ }
+}
+
+// only run while parsing the header (3 times)
+static int vorbis_validate(uint8 *data)
+{
+ static uint8 vorbis[6] = { 'v', 'o', 'r', 'b', 'i', 's' };
+ return memcmp(data, vorbis, 6) == 0;
+}
+
+// called from setup only, once per code book
+// (formula implied by specification)
+static int lookup1_values(int entries, int dim)
+{
+ int r = (int) floor(exp((float) log((float) entries) / dim));
+ if ((int) floor(pow((float) r+1, dim)) <= entries) // (int) cast for MinGW warning;
+ ++r; // floor() to avoid _ftol() when non-CRT
+ assert(pow((float) r+1, dim) > entries);
+ assert((int) floor(pow((float) r, dim)) <= entries); // (int),floor() as above
+ return r;
+}
+
+// called twice per file
+static void compute_twiddle_factors(int n, float *A, float *B, float *C)
+{
+ int n4 = n >> 2, n8 = n >> 3;
+ int k,k2;
+
+ for (k=k2=0; k < n4; ++k,k2+=2) {
+ A[k2 ] = (float) cos(4*k*M_PI/n);
+ A[k2+1] = (float) -sin(4*k*M_PI/n);
+ B[k2 ] = (float) cos((k2+1)*M_PI/n/2) * 0.5f;
+ B[k2+1] = (float) sin((k2+1)*M_PI/n/2) * 0.5f;
+ }
+ for (k=k2=0; k < n8; ++k,k2+=2) {
+ C[k2 ] = (float) cos(2*(k2+1)*M_PI/n);
+ C[k2+1] = (float) -sin(2*(k2+1)*M_PI/n);
+ }
+}
+
+static void compute_window(int n, float *window)
+{
+ int n2 = n >> 1, i;
+ for (i=0; i < n2; ++i)
+ window[i] = (float) sin(0.5 * M_PI * square((float) sin((i - 0 + 0.5) / n2 * 0.5 * M_PI)));
+}
+
+static void compute_bitreverse(int n, uint16 *rev)
+{
+ int ld = ilog(n) - 1; // ilog is off-by-one from normal definitions
+ int i, n8 = n >> 3;
+ for (i=0; i < n8; ++i)
+ rev[i] = (bit_reverse(i) >> (32-ld+3)) << 2;
+}
+
+static int init_blocksize(vorb *f, int b, int n)
+{
+ int n2 = n >> 1, n4 = n >> 2, n8 = n >> 3;
+ f->A[b] = (float *) setup_malloc(f, sizeof(float) * n2);
+ f->B[b] = (float *) setup_malloc(f, sizeof(float) * n2);
+ f->C[b] = (float *) setup_malloc(f, sizeof(float) * n4);
+ if (!f->A[b] || !f->B[b] || !f->C[b]) return error(f, VORBIS_outofmem);
+ compute_twiddle_factors(n, f->A[b], f->B[b], f->C[b]);
+ f->window[b] = (float *) setup_malloc(f, sizeof(float) * n2);
+ if (!f->window[b]) return error(f, VORBIS_outofmem);
+ compute_window(n, f->window[b]);
+ f->bit_reverse[b] = (uint16 *) setup_malloc(f, sizeof(uint16) * n8);
+ if (!f->bit_reverse[b]) return error(f, VORBIS_outofmem);
+ compute_bitreverse(n, f->bit_reverse[b]);
+ return TRUE;
+}
+
+static void neighbors(uint16 *x, int n, int *plow, int *phigh)
+{
+ int low = -1;
+ int high = 65536;
+ int i;
+ for (i=0; i < n; ++i) {
+ if (x[i] > low && x[i] < x[n]) { *plow = i; low = x[i]; }
+ if (x[i] < high && x[i] > x[n]) { *phigh = i; high = x[i]; }
+ }
+}
+
+// this has been repurposed so y is now the original index instead of y
+typedef struct
+{
+ uint16 x,y;
+} Point;
+
+static int STBV_CDECL point_compare(const void *p, const void *q)
+{
+ Point *a = (Point *) p;
+ Point *b = (Point *) q;
+ return a->x < b->x ? -1 : a->x > b->x;
+}
+
+//
+/////////////////////// END LEAF SETUP FUNCTIONS //////////////////////////
+
+
+#if defined(STB_VORBIS_NO_STDIO)
+ #define USE_MEMORY(z) TRUE
+#else
+ #define USE_MEMORY(z) ((z)->stream)
+#endif
+
+static uint8 get8(vorb *z)
+{
+ if (USE_MEMORY(z)) {
+ if (z->stream >= z->stream_end) { z->eof = TRUE; return 0; }
+ return *z->stream++;
+ }
+
+ #ifndef STB_VORBIS_NO_STDIO
+ {
+ int c = fgetc(z->f);
+ if (c == EOF) { z->eof = TRUE; return 0; }
+ return c;
+ }
+ #endif
+}
+
+static uint32 get32(vorb *f)
+{
+ uint32 x;
+ x = get8(f);
+ x += get8(f) << 8;
+ x += get8(f) << 16;
+ x += (uint32) get8(f) << 24;
+ return x;
+}
+
+static int getn(vorb *z, uint8 *data, int n)
+{
+ if (USE_MEMORY(z)) {
+ if (z->stream+n > z->stream_end) { z->eof = 1; return 0; }
+ memcpy(data, z->stream, n);
+ z->stream += n;
+ return 1;
+ }
+
+ #ifndef STB_VORBIS_NO_STDIO
+ if (fread(data, n, 1, z->f) == 1)
+ return 1;
+ else {
+ z->eof = 1;
+ return 0;
+ }
+ #endif
+}
+
+static void skip(vorb *z, int n)
+{
+ if (USE_MEMORY(z)) {
+ z->stream += n;
+ if (z->stream >= z->stream_end) z->eof = 1;
+ return;
+ }
+ #ifndef STB_VORBIS_NO_STDIO
+ {
+ long x = ftell(z->f);
+ fseek(z->f, x+n, SEEK_SET);
+ }
+ #endif
+}
+
+static int set_file_offset(stb_vorbis *f, unsigned int loc)
+{
+ #ifndef STB_VORBIS_NO_PUSHDATA_API
+ if (f->push_mode) return 0;
+ #endif
+ f->eof = 0;
+ if (USE_MEMORY(f)) {
+ if (f->stream_start + loc >= f->stream_end || f->stream_start + loc < f->stream_start) {
+ f->stream = f->stream_end;
+ f->eof = 1;
+ return 0;
+ } else {
+ f->stream = f->stream_start + loc;
+ return 1;
+ }
+ }
+ #ifndef STB_VORBIS_NO_STDIO
+ if (loc + f->f_start < loc || loc >= 0x80000000) {
+ loc = 0x7fffffff;
+ f->eof = 1;
+ } else {
+ loc += f->f_start;
+ }
+ if (!fseek(f->f, loc, SEEK_SET))
+ return 1;
+ f->eof = 1;
+ fseek(f->f, f->f_start, SEEK_END);
+ return 0;
+ #endif
+}
+
+
+static uint8 ogg_page_header[4] = { 0x4f, 0x67, 0x67, 0x53 };
+
+static int capture_pattern(vorb *f)
+{
+ if (0x4f != get8(f)) return FALSE;
+ if (0x67 != get8(f)) return FALSE;
+ if (0x67 != get8(f)) return FALSE;
+ if (0x53 != get8(f)) return FALSE;
+ return TRUE;
+}
+
+#define PAGEFLAG_continued_packet 1
+#define PAGEFLAG_first_page 2
+#define PAGEFLAG_last_page 4
+
+static int start_page_no_capturepattern(vorb *f)
+{
+ uint32 loc0,loc1,n;
+ // stream structure version
+ if (0 != get8(f)) return error(f, VORBIS_invalid_stream_structure_version);
+ // header flag
+ f->page_flag = get8(f);
+ // absolute granule position
+ loc0 = get32(f);
+ loc1 = get32(f);
+ // @TODO: validate loc0,loc1 as valid positions?
+ // stream serial number -- vorbis doesn't interleave, so discard
+ get32(f);
+ //if (f->serial != get32(f)) return error(f, VORBIS_incorrect_stream_serial_number);
+ // page sequence number
+ n = get32(f);
+ f->last_page = n;
+ // CRC32
+ get32(f);
+ // page_segments
+ f->segment_count = get8(f);
+ if (!getn(f, f->segments, f->segment_count))
+ return error(f, VORBIS_unexpected_eof);
+ // assume we _don't_ know any the sample position of any segments
+ f->end_seg_with_known_loc = -2;
+ if (loc0 != ~0U || loc1 != ~0U) {
+ int i;
+ // determine which packet is the last one that will complete
+ for (i=f->segment_count-1; i >= 0; --i)
+ if (f->segments[i] < 255)
+ break;
+ // 'i' is now the index of the _last_ segment of a packet that ends
+ if (i >= 0) {
+ f->end_seg_with_known_loc = i;
+ f->known_loc_for_packet = loc0;
+ }
+ }
+ if (f->first_decode) {
+ int i,len;
+ ProbedPage p;
+ len = 0;
+ for (i=0; i < f->segment_count; ++i)
+ len += f->segments[i];
+ len += 27 + f->segment_count;
+ p.page_start = f->first_audio_page_offset;
+ p.page_end = p.page_start + len;
+ p.last_decoded_sample = loc0;
+ f->p_first = p;
+ }
+ f->next_seg = 0;
+ return TRUE;
+}
+
+static int start_page(vorb *f)
+{
+ if (!capture_pattern(f)) return error(f, VORBIS_missing_capture_pattern);
+ return start_page_no_capturepattern(f);
+}
+
+static int start_packet(vorb *f)
+{
+ while (f->next_seg == -1) {
+ if (!start_page(f)) return FALSE;
+ if (f->page_flag & PAGEFLAG_continued_packet)
+ return error(f, VORBIS_continued_packet_flag_invalid);
+ }
+ f->last_seg = FALSE;
+ f->valid_bits = 0;
+ f->packet_bytes = 0;
+ f->bytes_in_seg = 0;
+ // f->next_seg is now valid
+ return TRUE;
+}
+
+static int maybe_start_packet(vorb *f)
+{
+ if (f->next_seg == -1) {
+ int x = get8(f);
+ if (f->eof) return FALSE; // EOF at page boundary is not an error!
+ if (0x4f != x ) return error(f, VORBIS_missing_capture_pattern);
+ if (0x67 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
+ if (0x67 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
+ if (0x53 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
+ if (!start_page_no_capturepattern(f)) return FALSE;
+ if (f->page_flag & PAGEFLAG_continued_packet) {
+ // set up enough state that we can read this packet if we want,
+ // e.g. during recovery
+ f->last_seg = FALSE;
+ f->bytes_in_seg = 0;
+ return error(f, VORBIS_continued_packet_flag_invalid);
+ }
+ }
+ return start_packet(f);
+}
+
+static int next_segment(vorb *f)
+{
+ int len;
+ if (f->last_seg) return 0;
+ if (f->next_seg == -1) {
+ f->last_seg_which = f->segment_count-1; // in case start_page fails
+ if (!start_page(f)) { f->last_seg = 1; return 0; }
+ if (!(f->page_flag & PAGEFLAG_continued_packet)) return error(f, VORBIS_continued_packet_flag_invalid);
+ }
+ len = f->segments[f->next_seg++];
+ if (len < 255) {
+ f->last_seg = TRUE;
+ f->last_seg_which = f->next_seg-1;
+ }
+ if (f->next_seg >= f->segment_count)
+ f->next_seg = -1;
+ assert(f->bytes_in_seg == 0);
+ f->bytes_in_seg = len;
+ return len;
+}
+
+#define EOP (-1)
+#define INVALID_BITS (-1)
+
+static int get8_packet_raw(vorb *f)
+{
+ if (!f->bytes_in_seg) { // CLANG!
+ if (f->last_seg) return EOP;
+ else if (!next_segment(f)) return EOP;
+ }
+ assert(f->bytes_in_seg > 0);
+ --f->bytes_in_seg;
+ ++f->packet_bytes;
+ return get8(f);
+}
+
+static int get8_packet(vorb *f)
+{
+ int x = get8_packet_raw(f);
+ f->valid_bits = 0;
+ return x;
+}
+
+static void flush_packet(vorb *f)
+{
+ while (get8_packet_raw(f) != EOP);
+}
+
+// @OPTIMIZE: this is the secondary bit decoder, so it's probably not as important
+// as the huffman decoder?
+static uint32 get_bits(vorb *f, int n)
+{
+ uint32 z;
+
+ if (f->valid_bits < 0) return 0;
+ if (f->valid_bits < n) {
+ if (n > 24) {
+ // the accumulator technique below would not work correctly in this case
+ z = get_bits(f, 24);
+ z += get_bits(f, n-24) << 24;
+ return z;
+ }
+ if (f->valid_bits == 0) f->acc = 0;
+ while (f->valid_bits < n) {
+ int z = get8_packet_raw(f);
+ if (z == EOP) {
+ f->valid_bits = INVALID_BITS;
+ return 0;
+ }
+ f->acc += z << f->valid_bits;
+ f->valid_bits += 8;
+ }
+ }
+ if (f->valid_bits < 0) return 0;
+ z = f->acc & ((1 << n)-1);
+ f->acc >>= n;
+ f->valid_bits -= n;
+ return z;
+}
+
+// @OPTIMIZE: primary accumulator for huffman
+// expand the buffer to as many bits as possible without reading off end of packet
+// it might be nice to allow f->valid_bits and f->acc to be stored in registers,
+// e.g. cache them locally and decode locally
+static __forceinline void prep_huffman(vorb *f)
+{
+ if (f->valid_bits <= 24) {
+ if (f->valid_bits == 0) f->acc = 0;
+ do {
+ int z;
+ if (f->last_seg && !f->bytes_in_seg) return;
+ z = get8_packet_raw(f);
+ if (z == EOP) return;
+ f->acc += (unsigned) z << f->valid_bits;
+ f->valid_bits += 8;
+ } while (f->valid_bits <= 24);
+ }
+}
+
+enum
+{
+ VORBIS_packet_id = 1,
+ VORBIS_packet_comment = 3,
+ VORBIS_packet_setup = 5
+};
+
+static int codebook_decode_scalar_raw(vorb *f, Codebook *c)
+{
+ int i;
+ prep_huffman(f);
+
+ if (c->codewords == NULL && c->sorted_codewords == NULL)
+ return -1;
+
+ // cases to use binary search: sorted_codewords && !c->codewords
+ // sorted_codewords && c->entries > 8
+ if (c->entries > 8 ? c->sorted_codewords!=NULL : !c->codewords) {
+ // binary search
+ uint32 code = bit_reverse(f->acc);
+ int x=0, n=c->sorted_entries, len;
+
+ while (n > 1) {
+ // invariant: sc[x] <= code < sc[x+n]
+ int m = x + (n >> 1);
+ if (c->sorted_codewords[m] <= code) {
+ x = m;
+ n -= (n>>1);
+ } else {
+ n >>= 1;
+ }
+ }
+ // x is now the sorted index
+ if (!c->sparse) x = c->sorted_values[x];
+ // x is now sorted index if sparse, or symbol otherwise
+ len = c->codeword_lengths[x];
+ if (f->valid_bits >= len) {
+ f->acc >>= len;
+ f->valid_bits -= len;
+ return x;
+ }
+
+ f->valid_bits = 0;
+ return -1;
+ }
+
+ // if small, linear search
+ assert(!c->sparse);
+ for (i=0; i < c->entries; ++i) {
+ if (c->codeword_lengths[i] == NO_CODE) continue;
+ if (c->codewords[i] == (f->acc & ((1 << c->codeword_lengths[i])-1))) {
+ if (f->valid_bits >= c->codeword_lengths[i]) {
+ f->acc >>= c->codeword_lengths[i];
+ f->valid_bits -= c->codeword_lengths[i];
+ return i;
+ }
+ f->valid_bits = 0;
+ return -1;
+ }
+ }
+
+ error(f, VORBIS_invalid_stream);
+ f->valid_bits = 0;
+ return -1;
+}
+
+#ifndef STB_VORBIS_NO_INLINE_DECODE
+
+#define DECODE_RAW(var, f,c) \
+ if (f->valid_bits < STB_VORBIS_FAST_HUFFMAN_LENGTH) \
+ prep_huffman(f); \
+ var = f->acc & FAST_HUFFMAN_TABLE_MASK; \
+ var = c->fast_huffman[var]; \
+ if (var >= 0) { \
+ int n = c->codeword_lengths[var]; \
+ f->acc >>= n; \
+ f->valid_bits -= n; \
+ if (f->valid_bits < 0) { f->valid_bits = 0; var = -1; } \
+ } else { \
+ var = codebook_decode_scalar_raw(f,c); \
+ }
+
+#else
+
+static int codebook_decode_scalar(vorb *f, Codebook *c)
+{
+ int i;
+ if (f->valid_bits < STB_VORBIS_FAST_HUFFMAN_LENGTH)
+ prep_huffman(f);
+ // fast huffman table lookup
+ i = f->acc & FAST_HUFFMAN_TABLE_MASK;
+ i = c->fast_huffman[i];
+ if (i >= 0) {
+ f->acc >>= c->codeword_lengths[i];
+ f->valid_bits -= c->codeword_lengths[i];
+ if (f->valid_bits < 0) { f->valid_bits = 0; return -1; }
+ return i;
+ }
+ return codebook_decode_scalar_raw(f,c);
+}
+
+#define DECODE_RAW(var,f,c) var = codebook_decode_scalar(f,c);
+
+#endif
+
+#define DECODE(var,f,c) \
+ DECODE_RAW(var,f,c) \
+ if (c->sparse) var = c->sorted_values[var];
+
+#ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ #define DECODE_VQ(var,f,c) DECODE_RAW(var,f,c)
+#else
+ #define DECODE_VQ(var,f,c) DECODE(var,f,c)
+#endif
+
+
+
+
+
+
+// CODEBOOK_ELEMENT_FAST is an optimization for the CODEBOOK_FLOATS case
+// where we avoid one addition
+#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off])
+#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off])
+#define CODEBOOK_ELEMENT_BASE(c) (0)
+
+static int codebook_decode_start(vorb *f, Codebook *c)
+{
+ int z = -1;
+
+ // type 0 is only legal in a scalar context
+ if (c->lookup_type == 0)
+ error(f, VORBIS_invalid_stream);
+ else {
+ DECODE_VQ(z,f,c);
+ if (c->sparse) assert(z < c->sorted_entries);
+ if (z < 0) { // check for EOP
+ if (!f->bytes_in_seg)
+ if (f->last_seg)
+ return z;
+ error(f, VORBIS_invalid_stream);
+ }
+ }
+ return z;
+}
+
+static int codebook_decode(vorb *f, Codebook *c, float *output, int len)
+{
+ int i,z = codebook_decode_start(f,c);
+ if (z < 0) return FALSE;
+ if (len > c->dimensions) len = c->dimensions;
+
+#ifdef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ if (c->lookup_type == 1) {
+ float last = CODEBOOK_ELEMENT_BASE(c);
+ int div = 1;
+ for (i=0; i < len; ++i) {
+ int off = (z / div) % c->lookup_values;
+ float val = CODEBOOK_ELEMENT_FAST(c,off) + last;
+ output[i] += val;
+ if (c->sequence_p) last = val + c->minimum_value;
+ div *= c->lookup_values;
+ }
+ return TRUE;
+ }
+#endif
+
+ z *= c->dimensions;
+ if (c->sequence_p) {
+ float last = CODEBOOK_ELEMENT_BASE(c);
+ for (i=0; i < len; ++i) {
+ float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
+ output[i] += val;
+ last = val + c->minimum_value;
+ }
+ } else {
+ float last = CODEBOOK_ELEMENT_BASE(c);
+ for (i=0; i < len; ++i) {
+ output[i] += CODEBOOK_ELEMENT_FAST(c,z+i) + last;
+ }
+ }
+
+ return TRUE;
+}
+
+static int codebook_decode_step(vorb *f, Codebook *c, float *output, int len, int step)
+{
+ int i,z = codebook_decode_start(f,c);
+ float last = CODEBOOK_ELEMENT_BASE(c);
+ if (z < 0) return FALSE;
+ if (len > c->dimensions) len = c->dimensions;
+
+#ifdef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ if (c->lookup_type == 1) {
+ int div = 1;
+ for (i=0; i < len; ++i) {
+ int off = (z / div) % c->lookup_values;
+ float val = CODEBOOK_ELEMENT_FAST(c,off) + last;
+ output[i*step] += val;
+ if (c->sequence_p) last = val;
+ div *= c->lookup_values;
+ }
+ return TRUE;
+ }
+#endif
+
+ z *= c->dimensions;
+ for (i=0; i < len; ++i) {
+ float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
+ output[i*step] += val;
+ if (c->sequence_p) last = val;
+ }
+
+ return TRUE;
+}
+
+static int codebook_decode_deinterleave_repeat(vorb *f, Codebook *c, float **outputs, int ch, int *c_inter_p, int *p_inter_p, int len, int total_decode)
+{
+ int c_inter = *c_inter_p;
+ int p_inter = *p_inter_p;
+ int i,z, effective = c->dimensions;
+
+ // type 0 is only legal in a scalar context
+ if (c->lookup_type == 0) return error(f, VORBIS_invalid_stream);
+
+ while (total_decode > 0) {
+ float last = CODEBOOK_ELEMENT_BASE(c);
+ DECODE_VQ(z,f,c);
+ #ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ assert(!c->sparse || z < c->sorted_entries);
+ #endif
+ if (z < 0) {
+ if (!f->bytes_in_seg)
+ if (f->last_seg) return FALSE;
+ return error(f, VORBIS_invalid_stream);
+ }
+
+ // if this will take us off the end of the buffers, stop short!
+ // we check by computing the length of the virtual interleaved
+ // buffer (len*ch), our current offset within it (p_inter*ch)+(c_inter),
+ // and the length we'll be using (effective)
+ if (c_inter + p_inter*ch + effective > len * ch) {
+ effective = len*ch - (p_inter*ch - c_inter);
+ }
+
+ #ifdef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ if (c->lookup_type == 1) {
+ int div = 1;
+ for (i=0; i < effective; ++i) {
+ int off = (z / div) % c->lookup_values;
+ float val = CODEBOOK_ELEMENT_FAST(c,off) + last;
+ if (outputs[c_inter])
+ outputs[c_inter][p_inter] += val;
+ if (++c_inter == ch) { c_inter = 0; ++p_inter; }
+ if (c->sequence_p) last = val;
+ div *= c->lookup_values;
+ }
+ } else
+ #endif
+ {
+ z *= c->dimensions;
+ if (c->sequence_p) {
+ for (i=0; i < effective; ++i) {
+ float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
+ if (outputs[c_inter])
+ outputs[c_inter][p_inter] += val;
+ if (++c_inter == ch) { c_inter = 0; ++p_inter; }
+ last = val;
+ }
+ } else {
+ for (i=0; i < effective; ++i) {
+ float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
+ if (outputs[c_inter])
+ outputs[c_inter][p_inter] += val;
+ if (++c_inter == ch) { c_inter = 0; ++p_inter; }
+ }
+ }
+ }
+
+ total_decode -= effective;
+ }
+ *c_inter_p = c_inter;
+ *p_inter_p = p_inter;
+ return TRUE;
+}
+
+static int predict_point(int x, int x0, int x1, int y0, int y1)
+{
+ int dy = y1 - y0;
+ int adx = x1 - x0;
+ // @OPTIMIZE: force int division to round in the right direction... is this necessary on x86?
+ int err = abs(dy) * (x - x0);
+ int off = err / adx;
+ return dy < 0 ? y0 - off : y0 + off;
+}
+
+// the following table is block-copied from the specification
+static float inverse_db_table[256] =
+{
+ 1.0649863e-07f, 1.1341951e-07f, 1.2079015e-07f, 1.2863978e-07f,
+ 1.3699951e-07f, 1.4590251e-07f, 1.5538408e-07f, 1.6548181e-07f,
+ 1.7623575e-07f, 1.8768855e-07f, 1.9988561e-07f, 2.1287530e-07f,
+ 2.2670913e-07f, 2.4144197e-07f, 2.5713223e-07f, 2.7384213e-07f,
+ 2.9163793e-07f, 3.1059021e-07f, 3.3077411e-07f, 3.5226968e-07f,
+ 3.7516214e-07f, 3.9954229e-07f, 4.2550680e-07f, 4.5315863e-07f,
+ 4.8260743e-07f, 5.1396998e-07f, 5.4737065e-07f, 5.8294187e-07f,
+ 6.2082472e-07f, 6.6116941e-07f, 7.0413592e-07f, 7.4989464e-07f,
+ 7.9862701e-07f, 8.5052630e-07f, 9.0579828e-07f, 9.6466216e-07f,
+ 1.0273513e-06f, 1.0941144e-06f, 1.1652161e-06f, 1.2409384e-06f,
+ 1.3215816e-06f, 1.4074654e-06f, 1.4989305e-06f, 1.5963394e-06f,
+ 1.7000785e-06f, 1.8105592e-06f, 1.9282195e-06f, 2.0535261e-06f,
+ 2.1869758e-06f, 2.3290978e-06f, 2.4804557e-06f, 2.6416497e-06f,
+ 2.8133190e-06f, 2.9961443e-06f, 3.1908506e-06f, 3.3982101e-06f,
+ 3.6190449e-06f, 3.8542308e-06f, 4.1047004e-06f, 4.3714470e-06f,
+ 4.6555282e-06f, 4.9580707e-06f, 5.2802740e-06f, 5.6234160e-06f,
+ 5.9888572e-06f, 6.3780469e-06f, 6.7925283e-06f, 7.2339451e-06f,
+ 7.7040476e-06f, 8.2047000e-06f, 8.7378876e-06f, 9.3057248e-06f,
+ 9.9104632e-06f, 1.0554501e-05f, 1.1240392e-05f, 1.1970856e-05f,
+ 1.2748789e-05f, 1.3577278e-05f, 1.4459606e-05f, 1.5399272e-05f,
+ 1.6400004e-05f, 1.7465768e-05f, 1.8600792e-05f, 1.9809576e-05f,
+ 2.1096914e-05f, 2.2467911e-05f, 2.3928002e-05f, 2.5482978e-05f,
+ 2.7139006e-05f, 2.8902651e-05f, 3.0780908e-05f, 3.2781225e-05f,
+ 3.4911534e-05f, 3.7180282e-05f, 3.9596466e-05f, 4.2169667e-05f,
+ 4.4910090e-05f, 4.7828601e-05f, 5.0936773e-05f, 5.4246931e-05f,
+ 5.7772202e-05f, 6.1526565e-05f, 6.5524908e-05f, 6.9783085e-05f,
+ 7.4317983e-05f, 7.9147585e-05f, 8.4291040e-05f, 8.9768747e-05f,
+ 9.5602426e-05f, 0.00010181521f, 0.00010843174f, 0.00011547824f,
+ 0.00012298267f, 0.00013097477f, 0.00013948625f, 0.00014855085f,
+ 0.00015820453f, 0.00016848555f, 0.00017943469f, 0.00019109536f,
+ 0.00020351382f, 0.00021673929f, 0.00023082423f, 0.00024582449f,
+ 0.00026179955f, 0.00027881276f, 0.00029693158f, 0.00031622787f,
+ 0.00033677814f, 0.00035866388f, 0.00038197188f, 0.00040679456f,
+ 0.00043323036f, 0.00046138411f, 0.00049136745f, 0.00052329927f,
+ 0.00055730621f, 0.00059352311f, 0.00063209358f, 0.00067317058f,
+ 0.00071691700f, 0.00076350630f, 0.00081312324f, 0.00086596457f,
+ 0.00092223983f, 0.00098217216f, 0.0010459992f, 0.0011139742f,
+ 0.0011863665f, 0.0012634633f, 0.0013455702f, 0.0014330129f,
+ 0.0015261382f, 0.0016253153f, 0.0017309374f, 0.0018434235f,
+ 0.0019632195f, 0.0020908006f, 0.0022266726f, 0.0023713743f,
+ 0.0025254795f, 0.0026895994f, 0.0028643847f, 0.0030505286f,
+ 0.0032487691f, 0.0034598925f, 0.0036847358f, 0.0039241906f,
+ 0.0041792066f, 0.0044507950f, 0.0047400328f, 0.0050480668f,
+ 0.0053761186f, 0.0057254891f, 0.0060975636f, 0.0064938176f,
+ 0.0069158225f, 0.0073652516f, 0.0078438871f, 0.0083536271f,
+ 0.0088964928f, 0.009474637f, 0.010090352f, 0.010746080f,
+ 0.011444421f, 0.012188144f, 0.012980198f, 0.013823725f,
+ 0.014722068f, 0.015678791f, 0.016697687f, 0.017782797f,
+ 0.018938423f, 0.020169149f, 0.021479854f, 0.022875735f,
+ 0.024362330f, 0.025945531f, 0.027631618f, 0.029427276f,
+ 0.031339626f, 0.033376252f, 0.035545228f, 0.037855157f,
+ 0.040315199f, 0.042935108f, 0.045725273f, 0.048696758f,
+ 0.051861348f, 0.055231591f, 0.058820850f, 0.062643361f,
+ 0.066714279f, 0.071049749f, 0.075666962f, 0.080584227f,
+ 0.085821044f, 0.091398179f, 0.097337747f, 0.10366330f,
+ 0.11039993f, 0.11757434f, 0.12521498f, 0.13335215f,
+ 0.14201813f, 0.15124727f, 0.16107617f, 0.17154380f,
+ 0.18269168f, 0.19456402f, 0.20720788f, 0.22067342f,
+ 0.23501402f, 0.25028656f, 0.26655159f, 0.28387361f,
+ 0.30232132f, 0.32196786f, 0.34289114f, 0.36517414f,
+ 0.38890521f, 0.41417847f, 0.44109412f, 0.46975890f,
+ 0.50028648f, 0.53279791f, 0.56742212f, 0.60429640f,
+ 0.64356699f, 0.68538959f, 0.72993007f, 0.77736504f,
+ 0.82788260f, 0.88168307f, 0.9389798f, 1.0f
+};
+
+
+// @OPTIMIZE: if you want to replace this bresenham line-drawing routine,
+// note that you must produce bit-identical output to decode correctly;
+// this specific sequence of operations is specified in the spec (it's
+// drawing integer-quantized frequency-space lines that the encoder
+// expects to be exactly the same)
+// ... also, isn't the whole point of Bresenham's algorithm to NOT
+// have to divide in the setup? sigh.
+#ifndef STB_VORBIS_NO_DEFER_FLOOR
+#define LINE_OP(a,b) a *= b
+#else
+#define LINE_OP(a,b) a = b
+#endif
+
+#ifdef STB_VORBIS_DIVIDE_TABLE
+#define DIVTAB_NUMER 32
+#define DIVTAB_DENOM 64
+int8 integer_divide_table[DIVTAB_NUMER][DIVTAB_DENOM]; // 2KB
+#endif
+
+static __forceinline void draw_line(float *output, int x0, int y0, int x1, int y1, int n)
+{
+ int dy = y1 - y0;
+ int adx = x1 - x0;
+ int ady = abs(dy);
+ int base;
+ int x=x0,y=y0;
+ int err = 0;
+ int sy;
+
+#ifdef STB_VORBIS_DIVIDE_TABLE
+ if (adx < DIVTAB_DENOM && ady < DIVTAB_NUMER) {
+ if (dy < 0) {
+ base = -integer_divide_table[ady][adx];
+ sy = base-1;
+ } else {
+ base = integer_divide_table[ady][adx];
+ sy = base+1;
+ }
+ } else {
+ base = dy / adx;
+ if (dy < 0)
+ sy = base - 1;
+ else
+ sy = base+1;
+ }
+#else
+ base = dy / adx;
+ if (dy < 0)
+ sy = base - 1;
+ else
+ sy = base+1;
+#endif
+ ady -= abs(base) * adx;
+ if (x1 > n) x1 = n;
+ if (x < x1) {
+ LINE_OP(output[x], inverse_db_table[y]);
+ for (++x; x < x1; ++x) {
+ err += ady;
+ if (err >= adx) {
+ err -= adx;
+ y += sy;
+ } else
+ y += base;
+ LINE_OP(output[x], inverse_db_table[y]);
+ }
+ }
+}
+
+static int residue_decode(vorb *f, Codebook *book, float *target, int offset, int n, int rtype)
+{
+ int k;
+ if (rtype == 0) {
+ int step = n / book->dimensions;
+ for (k=0; k < step; ++k)
+ if (!codebook_decode_step(f, book, target+offset+k, n-offset-k, step))
+ return FALSE;
+ } else {
+ for (k=0; k < n; ) {
+ if (!codebook_decode(f, book, target+offset, n-k))
+ return FALSE;
+ k += book->dimensions;
+ offset += book->dimensions;
+ }
+ }
+ return TRUE;
+}
+
+static void decode_residue(vorb *f, float *residue_buffers[], int ch, int n, int rn, uint8 *do_not_decode)
+{
+ int i,j,pass;
+ Residue *r = f->residue_config + rn;
+ int rtype = f->residue_types[rn];
+ int c = r->classbook;
+ int classwords = f->codebooks[c].dimensions;
+ int n_read = r->end - r->begin;
+ int part_read = n_read / r->part_size;
+ int temp_alloc_point = temp_alloc_save(f);
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ uint8 ***part_classdata = (uint8 ***) temp_block_array(f,f->channels, part_read * sizeof(**part_classdata));
+ #else
+ int **classifications = (int **) temp_block_array(f,f->channels, part_read * sizeof(**classifications));
+ #endif
+
+ CHECK(f);
+
+ for (i=0; i < ch; ++i)
+ if (!do_not_decode[i])
+ memset(residue_buffers[i], 0, sizeof(float) * n);
+
+ if (rtype == 2 && ch != 1) {
+ for (j=0; j < ch; ++j)
+ if (!do_not_decode[j])
+ break;
+ if (j == ch)
+ goto done;
+
+ for (pass=0; pass < 8; ++pass) {
+ int pcount = 0, class_set = 0;
+ if (ch == 2) {
+ while (pcount < part_read) {
+ int z = r->begin + pcount*r->part_size;
+ int c_inter = (z & 1), p_inter = z>>1;
+ if (pass == 0) {
+ Codebook *c = f->codebooks+r->classbook;
+ int q;
+ DECODE(q,f,c);
+ if (q == EOP) goto done;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ part_classdata[0][class_set] = r->classdata[q];
+ #else
+ for (i=classwords-1; i >= 0; --i) {
+ classifications[0][i+pcount] = q % r->classifications;
+ q /= r->classifications;
+ }
+ #endif
+ }
+ for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
+ int z = r->begin + pcount*r->part_size;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ int c = part_classdata[0][class_set][i];
+ #else
+ int c = classifications[0][pcount];
+ #endif
+ int b = r->residue_books[c][pass];
+ if (b >= 0) {
+ Codebook *book = f->codebooks + b;
+ #ifdef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
+ goto done;
+ #else
+ // saves 1%
+ if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
+ goto done;
+ #endif
+ } else {
+ z += r->part_size;
+ c_inter = z & 1;
+ p_inter = z >> 1;
+ }
+ }
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ ++class_set;
+ #endif
+ }
+ } else if (ch == 1) {
+ while (pcount < part_read) {
+ int z = r->begin + pcount*r->part_size;
+ int c_inter = 0, p_inter = z;
+ if (pass == 0) {
+ Codebook *c = f->codebooks+r->classbook;
+ int q;
+ DECODE(q,f,c);
+ if (q == EOP) goto done;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ part_classdata[0][class_set] = r->classdata[q];
+ #else
+ for (i=classwords-1; i >= 0; --i) {
+ classifications[0][i+pcount] = q % r->classifications;
+ q /= r->classifications;
+ }
+ #endif
+ }
+ for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
+ int z = r->begin + pcount*r->part_size;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ int c = part_classdata[0][class_set][i];
+ #else
+ int c = classifications[0][pcount];
+ #endif
+ int b = r->residue_books[c][pass];
+ if (b >= 0) {
+ Codebook *book = f->codebooks + b;
+ if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
+ goto done;
+ } else {
+ z += r->part_size;
+ c_inter = 0;
+ p_inter = z;
+ }
+ }
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ ++class_set;
+ #endif
+ }
+ } else {
+ while (pcount < part_read) {
+ int z = r->begin + pcount*r->part_size;
+ int c_inter = z % ch, p_inter = z/ch;
+ if (pass == 0) {
+ Codebook *c = f->codebooks+r->classbook;
+ int q;
+ DECODE(q,f,c);
+ if (q == EOP) goto done;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ part_classdata[0][class_set] = r->classdata[q];
+ #else
+ for (i=classwords-1; i >= 0; --i) {
+ classifications[0][i+pcount] = q % r->classifications;
+ q /= r->classifications;
+ }
+ #endif
+ }
+ for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
+ int z = r->begin + pcount*r->part_size;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ int c = part_classdata[0][class_set][i];
+ #else
+ int c = classifications[0][pcount];
+ #endif
+ int b = r->residue_books[c][pass];
+ if (b >= 0) {
+ Codebook *book = f->codebooks + b;
+ if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
+ goto done;
+ } else {
+ z += r->part_size;
+ c_inter = z % ch;
+ p_inter = z / ch;
+ }
+ }
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ ++class_set;
+ #endif
+ }
+ }
+ }
+ goto done;
+ }
+ CHECK(f);
+
+ for (pass=0; pass < 8; ++pass) {
+ int pcount = 0, class_set=0;
+ while (pcount < part_read) {
+ if (pass == 0) {
+ for (j=0; j < ch; ++j) {
+ if (!do_not_decode[j]) {
+ Codebook *c = f->codebooks+r->classbook;
+ int temp;
+ DECODE(temp,f,c);
+ if (temp == EOP) goto done;
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ part_classdata[j][class_set] = r->classdata[temp];
+ #else
+ for (i=classwords-1; i >= 0; --i) {
+ classifications[j][i+pcount] = temp % r->classifications;
+ temp /= r->classifications;
+ }
+ #endif
+ }
+ }
+ }
+ for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
+ for (j=0; j < ch; ++j) {
+ if (!do_not_decode[j]) {
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ int c = part_classdata[j][class_set][i];
+ #else
+ int c = classifications[j][pcount];
+ #endif
+ int b = r->residue_books[c][pass];
+ if (b >= 0) {
+ float *target = residue_buffers[j];
+ int offset = r->begin + pcount * r->part_size;
+ int n = r->part_size;
+ Codebook *book = f->codebooks + b;
+ if (!residue_decode(f, book, target, offset, n, rtype))
+ goto done;
+ }
+ }
+ }
+ }
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ ++class_set;
+ #endif
+ }
+ }
+ done:
+ CHECK(f);
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ temp_free(f,part_classdata);
+ #else
+ temp_free(f,classifications);
+ #endif
+ temp_alloc_restore(f,temp_alloc_point);
+}
+
+
+#if 0
+// slow way for debugging
+void inverse_mdct_slow(float *buffer, int n)
+{
+ int i,j;
+ int n2 = n >> 1;
+ float *x = (float *) malloc(sizeof(*x) * n2);
+ memcpy(x, buffer, sizeof(*x) * n2);
+ for (i=0; i < n; ++i) {
+ float acc = 0;
+ for (j=0; j < n2; ++j)
+ // formula from paper:
+ //acc += n/4.0f * x[j] * (float) cos(M_PI / 2 / n * (2 * i + 1 + n/2.0)*(2*j+1));
+ // formula from wikipedia
+ //acc += 2.0f / n2 * x[j] * (float) cos(M_PI/n2 * (i + 0.5 + n2/2)*(j + 0.5));
+ // these are equivalent, except the formula from the paper inverts the multiplier!
+ // however, what actually works is NO MULTIPLIER!?!
+ //acc += 64 * 2.0f / n2 * x[j] * (float) cos(M_PI/n2 * (i + 0.5 + n2/2)*(j + 0.5));
+ acc += x[j] * (float) cos(M_PI / 2 / n * (2 * i + 1 + n/2.0)*(2*j+1));
+ buffer[i] = acc;
+ }
+ free(x);
+}
+#elif 0
+// same as above, but just barely able to run in real time on modern machines
+void inverse_mdct_slow(float *buffer, int n, vorb *f, int blocktype)
+{
+ float mcos[16384];
+ int i,j;
+ int n2 = n >> 1, nmask = (n << 2) -1;
+ float *x = (float *) malloc(sizeof(*x) * n2);
+ memcpy(x, buffer, sizeof(*x) * n2);
+ for (i=0; i < 4*n; ++i)
+ mcos[i] = (float) cos(M_PI / 2 * i / n);
+
+ for (i=0; i < n; ++i) {
+ float acc = 0;
+ for (j=0; j < n2; ++j)
+ acc += x[j] * mcos[(2 * i + 1 + n2)*(2*j+1) & nmask];
+ buffer[i] = acc;
+ }
+ free(x);
+}
+#elif 0
+// transform to use a slow dct-iv; this is STILL basically trivial,
+// but only requires half as many ops
+void dct_iv_slow(float *buffer, int n)
+{
+ float mcos[16384];
+ float x[2048];
+ int i,j;
+ int n2 = n >> 1, nmask = (n << 3) - 1;
+ memcpy(x, buffer, sizeof(*x) * n);
+ for (i=0; i < 8*n; ++i)
+ mcos[i] = (float) cos(M_PI / 4 * i / n);
+ for (i=0; i < n; ++i) {
+ float acc = 0;
+ for (j=0; j < n; ++j)
+ acc += x[j] * mcos[((2 * i + 1)*(2*j+1)) & nmask];
+ buffer[i] = acc;
+ }
+}
+
+void inverse_mdct_slow(float *buffer, int n, vorb *f, int blocktype)
+{
+ int i, n4 = n >> 2, n2 = n >> 1, n3_4 = n - n4;
+ float temp[4096];
+
+ memcpy(temp, buffer, n2 * sizeof(float));
+ dct_iv_slow(temp, n2); // returns -c'-d, a-b'
+
+ for (i=0; i < n4 ; ++i) buffer[i] = temp[i+n4]; // a-b'
+ for ( ; i < n3_4; ++i) buffer[i] = -temp[n3_4 - i - 1]; // b-a', c+d'
+ for ( ; i < n ; ++i) buffer[i] = -temp[i - n3_4]; // c'+d
+}
+#endif
+
+#ifndef LIBVORBIS_MDCT
+#define LIBVORBIS_MDCT 0
+#endif
+
+#if LIBVORBIS_MDCT
+// directly call the vorbis MDCT using an interface documented
+// by Jeff Roberts... useful for performance comparison
+typedef struct
+{
+ int n;
+ int log2n;
+
+ float *trig;
+ int *bitrev;
+
+ float scale;
+} mdct_lookup;
+
+extern void mdct_init(mdct_lookup *lookup, int n);
+extern void mdct_clear(mdct_lookup *l);
+extern void mdct_backward(mdct_lookup *init, float *in, float *out);
+
+mdct_lookup M1,M2;
+
+void inverse_mdct(float *buffer, int n, vorb *f, int blocktype)
+{
+ mdct_lookup *M;
+ if (M1.n == n) M = &M1;
+ else if (M2.n == n) M = &M2;
+ else if (M1.n == 0) { mdct_init(&M1, n); M = &M1; }
+ else {
+ if (M2.n) __asm int 3;
+ mdct_init(&M2, n);
+ M = &M2;
+ }
+
+ mdct_backward(M, buffer, buffer);
+}
+#endif
+
+
+// the following were split out into separate functions while optimizing;
+// they could be pushed back up but eh. __forceinline showed no change;
+// they're probably already being inlined.
+static void imdct_step3_iter0_loop(int n, float *e, int i_off, int k_off, float *A)
+{
+ float *ee0 = e + i_off;
+ float *ee2 = ee0 + k_off;
+ int i;
+
+ assert((n & 3) == 0);
+ for (i=(n>>2); i > 0; --i) {
+ float k00_20, k01_21;
+ k00_20 = ee0[ 0] - ee2[ 0];
+ k01_21 = ee0[-1] - ee2[-1];
+ ee0[ 0] += ee2[ 0];//ee0[ 0] = ee0[ 0] + ee2[ 0];
+ ee0[-1] += ee2[-1];//ee0[-1] = ee0[-1] + ee2[-1];
+ ee2[ 0] = k00_20 * A[0] - k01_21 * A[1];
+ ee2[-1] = k01_21 * A[0] + k00_20 * A[1];
+ A += 8;
+
+ k00_20 = ee0[-2] - ee2[-2];
+ k01_21 = ee0[-3] - ee2[-3];
+ ee0[-2] += ee2[-2];//ee0[-2] = ee0[-2] + ee2[-2];
+ ee0[-3] += ee2[-3];//ee0[-3] = ee0[-3] + ee2[-3];
+ ee2[-2] = k00_20 * A[0] - k01_21 * A[1];
+ ee2[-3] = k01_21 * A[0] + k00_20 * A[1];
+ A += 8;
+
+ k00_20 = ee0[-4] - ee2[-4];
+ k01_21 = ee0[-5] - ee2[-5];
+ ee0[-4] += ee2[-4];//ee0[-4] = ee0[-4] + ee2[-4];
+ ee0[-5] += ee2[-5];//ee0[-5] = ee0[-5] + ee2[-5];
+ ee2[-4] = k00_20 * A[0] - k01_21 * A[1];
+ ee2[-5] = k01_21 * A[0] + k00_20 * A[1];
+ A += 8;
+
+ k00_20 = ee0[-6] - ee2[-6];
+ k01_21 = ee0[-7] - ee2[-7];
+ ee0[-6] += ee2[-6];//ee0[-6] = ee0[-6] + ee2[-6];
+ ee0[-7] += ee2[-7];//ee0[-7] = ee0[-7] + ee2[-7];
+ ee2[-6] = k00_20 * A[0] - k01_21 * A[1];
+ ee2[-7] = k01_21 * A[0] + k00_20 * A[1];
+ A += 8;
+ ee0 -= 8;
+ ee2 -= 8;
+ }
+}
+
+static void imdct_step3_inner_r_loop(int lim, float *e, int d0, int k_off, float *A, int k1)
+{
+ int i;
+ float k00_20, k01_21;
+
+ float *e0 = e + d0;
+ float *e2 = e0 + k_off;
+
+ for (i=lim >> 2; i > 0; --i) {
+ k00_20 = e0[-0] - e2[-0];
+ k01_21 = e0[-1] - e2[-1];
+ e0[-0] += e2[-0];//e0[-0] = e0[-0] + e2[-0];
+ e0[-1] += e2[-1];//e0[-1] = e0[-1] + e2[-1];
+ e2[-0] = (k00_20)*A[0] - (k01_21) * A[1];
+ e2[-1] = (k01_21)*A[0] + (k00_20) * A[1];
+
+ A += k1;
+
+ k00_20 = e0[-2] - e2[-2];
+ k01_21 = e0[-3] - e2[-3];
+ e0[-2] += e2[-2];//e0[-2] = e0[-2] + e2[-2];
+ e0[-3] += e2[-3];//e0[-3] = e0[-3] + e2[-3];
+ e2[-2] = (k00_20)*A[0] - (k01_21) * A[1];
+ e2[-3] = (k01_21)*A[0] + (k00_20) * A[1];
+
+ A += k1;
+
+ k00_20 = e0[-4] - e2[-4];
+ k01_21 = e0[-5] - e2[-5];
+ e0[-4] += e2[-4];//e0[-4] = e0[-4] + e2[-4];
+ e0[-5] += e2[-5];//e0[-5] = e0[-5] + e2[-5];
+ e2[-4] = (k00_20)*A[0] - (k01_21) * A[1];
+ e2[-5] = (k01_21)*A[0] + (k00_20) * A[1];
+
+ A += k1;
+
+ k00_20 = e0[-6] - e2[-6];
+ k01_21 = e0[-7] - e2[-7];
+ e0[-6] += e2[-6];//e0[-6] = e0[-6] + e2[-6];
+ e0[-7] += e2[-7];//e0[-7] = e0[-7] + e2[-7];
+ e2[-6] = (k00_20)*A[0] - (k01_21) * A[1];
+ e2[-7] = (k01_21)*A[0] + (k00_20) * A[1];
+
+ e0 -= 8;
+ e2 -= 8;
+
+ A += k1;
+ }
+}
+
+static void imdct_step3_inner_s_loop(int n, float *e, int i_off, int k_off, float *A, int a_off, int k0)
+{
+ int i;
+ float A0 = A[0];
+ float A1 = A[0+1];
+ float A2 = A[0+a_off];
+ float A3 = A[0+a_off+1];
+ float A4 = A[0+a_off*2+0];
+ float A5 = A[0+a_off*2+1];
+ float A6 = A[0+a_off*3+0];
+ float A7 = A[0+a_off*3+1];
+
+ float k00,k11;
+
+ float *ee0 = e +i_off;
+ float *ee2 = ee0+k_off;
+
+ for (i=n; i > 0; --i) {
+ k00 = ee0[ 0] - ee2[ 0];
+ k11 = ee0[-1] - ee2[-1];
+ ee0[ 0] = ee0[ 0] + ee2[ 0];
+ ee0[-1] = ee0[-1] + ee2[-1];
+ ee2[ 0] = (k00) * A0 - (k11) * A1;
+ ee2[-1] = (k11) * A0 + (k00) * A1;
+
+ k00 = ee0[-2] - ee2[-2];
+ k11 = ee0[-3] - ee2[-3];
+ ee0[-2] = ee0[-2] + ee2[-2];
+ ee0[-3] = ee0[-3] + ee2[-3];
+ ee2[-2] = (k00) * A2 - (k11) * A3;
+ ee2[-3] = (k11) * A2 + (k00) * A3;
+
+ k00 = ee0[-4] - ee2[-4];
+ k11 = ee0[-5] - ee2[-5];
+ ee0[-4] = ee0[-4] + ee2[-4];
+ ee0[-5] = ee0[-5] + ee2[-5];
+ ee2[-4] = (k00) * A4 - (k11) * A5;
+ ee2[-5] = (k11) * A4 + (k00) * A5;
+
+ k00 = ee0[-6] - ee2[-6];
+ k11 = ee0[-7] - ee2[-7];
+ ee0[-6] = ee0[-6] + ee2[-6];
+ ee0[-7] = ee0[-7] + ee2[-7];
+ ee2[-6] = (k00) * A6 - (k11) * A7;
+ ee2[-7] = (k11) * A6 + (k00) * A7;
+
+ ee0 -= k0;
+ ee2 -= k0;
+ }
+}
+
+static __forceinline void iter_54(float *z)
+{
+ float k00,k11,k22,k33;
+ float y0,y1,y2,y3;
+
+ k00 = z[ 0] - z[-4];
+ y0 = z[ 0] + z[-4];
+ y2 = z[-2] + z[-6];
+ k22 = z[-2] - z[-6];
+
+ z[-0] = y0 + y2; // z0 + z4 + z2 + z6
+ z[-2] = y0 - y2; // z0 + z4 - z2 - z6
+
+ // done with y0,y2
+
+ k33 = z[-3] - z[-7];
+
+ z[-4] = k00 + k33; // z0 - z4 + z3 - z7
+ z[-6] = k00 - k33; // z0 - z4 - z3 + z7
+
+ // done with k33
+
+ k11 = z[-1] - z[-5];
+ y1 = z[-1] + z[-5];
+ y3 = z[-3] + z[-7];
+
+ z[-1] = y1 + y3; // z1 + z5 + z3 + z7
+ z[-3] = y1 - y3; // z1 + z5 - z3 - z7
+ z[-5] = k11 - k22; // z1 - z5 + z2 - z6
+ z[-7] = k11 + k22; // z1 - z5 - z2 + z6
+}
+
+static void imdct_step3_inner_s_loop_ld654(int n, float *e, int i_off, float *A, int base_n)
+{
+ int a_off = base_n >> 3;
+ float A2 = A[0+a_off];
+ float *z = e + i_off;
+ float *base = z - 16 * n;
+
+ while (z > base) {
+ float k00,k11;
+
+ k00 = z[-0] - z[-8];
+ k11 = z[-1] - z[-9];
+ z[-0] = z[-0] + z[-8];
+ z[-1] = z[-1] + z[-9];
+ z[-8] = k00;
+ z[-9] = k11 ;
+
+ k00 = z[ -2] - z[-10];
+ k11 = z[ -3] - z[-11];
+ z[ -2] = z[ -2] + z[-10];
+ z[ -3] = z[ -3] + z[-11];
+ z[-10] = (k00+k11) * A2;
+ z[-11] = (k11-k00) * A2;
+
+ k00 = z[-12] - z[ -4]; // reverse to avoid a unary negation
+ k11 = z[ -5] - z[-13];
+ z[ -4] = z[ -4] + z[-12];
+ z[ -5] = z[ -5] + z[-13];
+ z[-12] = k11;
+ z[-13] = k00;
+
+ k00 = z[-14] - z[ -6]; // reverse to avoid a unary negation
+ k11 = z[ -7] - z[-15];
+ z[ -6] = z[ -6] + z[-14];
+ z[ -7] = z[ -7] + z[-15];
+ z[-14] = (k00+k11) * A2;
+ z[-15] = (k00-k11) * A2;
+
+ iter_54(z);
+ iter_54(z-8);
+ z -= 16;
+ }
+}
+
+static void inverse_mdct(float *buffer, int n, vorb *f, int blocktype)
+{
+ int n2 = n >> 1, n4 = n >> 2, n8 = n >> 3, l;
+ int ld;
+ // @OPTIMIZE: reduce register pressure by using fewer variables?
+ int save_point = temp_alloc_save(f);
+ float *buf2 = (float *) temp_alloc(f, n2 * sizeof(*buf2));
+ float *u=NULL,*v=NULL;
+ // twiddle factors
+ float *A = f->A[blocktype];
+
+ // IMDCT algorithm from "The use of multirate filter banks for coding of high quality digital audio"
+ // See notes about bugs in that paper in less-optimal implementation 'inverse_mdct_old' after this function.
+
+ // kernel from paper
+
+
+ // merged:
+ // copy and reflect spectral data
+ // step 0
+
+ // note that it turns out that the items added together during
+ // this step are, in fact, being added to themselves (as reflected
+ // by step 0). inexplicable inefficiency! this became obvious
+ // once I combined the passes.
+
+ // so there's a missing 'times 2' here (for adding X to itself).
+ // this propogates through linearly to the end, where the numbers
+ // are 1/2 too small, and need to be compensated for.
+
+ {
+ float *d,*e, *AA, *e_stop;
+ d = &buf2[n2-2];
+ AA = A;
+ e = &buffer[0];
+ e_stop = &buffer[n2];
+ while (e != e_stop) {
+ d[1] = (e[0] * AA[0] - e[2]*AA[1]);
+ d[0] = (e[0] * AA[1] + e[2]*AA[0]);
+ d -= 2;
+ AA += 2;
+ e += 4;
+ }
+
+ e = &buffer[n2-3];
+ while (d >= buf2) {
+ d[1] = (-e[2] * AA[0] - -e[0]*AA[1]);
+ d[0] = (-e[2] * AA[1] + -e[0]*AA[0]);
+ d -= 2;
+ AA += 2;
+ e -= 4;
+ }
+ }
+
+ // now we use symbolic names for these, so that we can
+ // possibly swap their meaning as we change which operations
+ // are in place
+
+ u = buffer;
+ v = buf2;
+
+ // step 2 (paper output is w, now u)
+ // this could be in place, but the data ends up in the wrong
+ // place... _somebody_'s got to swap it, so this is nominated
+ {
+ float *AA = &A[n2-8];
+ float *d0,*d1, *e0, *e1;
+
+ e0 = &v[n4];
+ e1 = &v[0];
+
+ d0 = &u[n4];
+ d1 = &u[0];
+
+ while (AA >= A) {
+ float v40_20, v41_21;
+
+ v41_21 = e0[1] - e1[1];
+ v40_20 = e0[0] - e1[0];
+ d0[1] = e0[1] + e1[1];
+ d0[0] = e0[0] + e1[0];
+ d1[1] = v41_21*AA[4] - v40_20*AA[5];
+ d1[0] = v40_20*AA[4] + v41_21*AA[5];
+
+ v41_21 = e0[3] - e1[3];
+ v40_20 = e0[2] - e1[2];
+ d0[3] = e0[3] + e1[3];
+ d0[2] = e0[2] + e1[2];
+ d1[3] = v41_21*AA[0] - v40_20*AA[1];
+ d1[2] = v40_20*AA[0] + v41_21*AA[1];
+
+ AA -= 8;
+
+ d0 += 4;
+ d1 += 4;
+ e0 += 4;
+ e1 += 4;
+ }
+ }
+
+ // step 3
+ ld = ilog(n) - 1; // ilog is off-by-one from normal definitions
+
+ // optimized step 3:
+
+ // the original step3 loop can be nested r inside s or s inside r;
+ // it's written originally as s inside r, but this is dumb when r
+ // iterates many times, and s few. So I have two copies of it and
+ // switch between them halfway.
+
+ // this is iteration 0 of step 3
+ imdct_step3_iter0_loop(n >> 4, u, n2-1-n4*0, -(n >> 3), A);
+ imdct_step3_iter0_loop(n >> 4, u, n2-1-n4*1, -(n >> 3), A);
+
+ // this is iteration 1 of step 3
+ imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*0, -(n >> 4), A, 16);
+ imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*1, -(n >> 4), A, 16);
+ imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*2, -(n >> 4), A, 16);
+ imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*3, -(n >> 4), A, 16);
+
+ l=2;
+ for (; l < (ld-3)>>1; ++l) {
+ int k0 = n >> (l+2), k0_2 = k0>>1;
+ int lim = 1 << (l+1);
+ int i;
+ for (i=0; i < lim; ++i)
+ imdct_step3_inner_r_loop(n >> (l+4), u, n2-1 - k0*i, -k0_2, A, 1 << (l+3));
+ }
+
+ for (; l < ld-6; ++l) {
+ int k0 = n >> (l+2), k1 = 1 << (l+3), k0_2 = k0>>1;
+ int rlim = n >> (l+6), r;
+ int lim = 1 << (l+1);
+ int i_off;
+ float *A0 = A;
+ i_off = n2-1;
+ for (r=rlim; r > 0; --r) {
+ imdct_step3_inner_s_loop(lim, u, i_off, -k0_2, A0, k1, k0);
+ A0 += k1*4;
+ i_off -= 8;
+ }
+ }
+
+ // iterations with count:
+ // ld-6,-5,-4 all interleaved together
+ // the big win comes from getting rid of needless flops
+ // due to the constants on pass 5 & 4 being all 1 and 0;
+ // combining them to be simultaneous to improve cache made little difference
+ imdct_step3_inner_s_loop_ld654(n >> 5, u, n2-1, A, n);
+
+ // output is u
+
+ // step 4, 5, and 6
+ // cannot be in-place because of step 5
+ {
+ uint16 *bitrev = f->bit_reverse[blocktype];
+ // weirdly, I'd have thought reading sequentially and writing
+ // erratically would have been better than vice-versa, but in
+ // fact that's not what my testing showed. (That is, with
+ // j = bitreverse(i), do you read i and write j, or read j and write i.)
+
+ float *d0 = &v[n4-4];
+ float *d1 = &v[n2-4];
+ while (d0 >= v) {
+ int k4;
+
+ k4 = bitrev[0];
+ d1[3] = u[k4+0];
+ d1[2] = u[k4+1];
+ d0[3] = u[k4+2];
+ d0[2] = u[k4+3];
+
+ k4 = bitrev[1];
+ d1[1] = u[k4+0];
+ d1[0] = u[k4+1];
+ d0[1] = u[k4+2];
+ d0[0] = u[k4+3];
+
+ d0 -= 4;
+ d1 -= 4;
+ bitrev += 2;
+ }
+ }
+ // (paper output is u, now v)
+
+
+ // data must be in buf2
+ assert(v == buf2);
+
+ // step 7 (paper output is v, now v)
+ // this is now in place
+ {
+ float *C = f->C[blocktype];
+ float *d, *e;
+
+ d = v;
+ e = v + n2 - 4;
+
+ while (d < e) {
+ float a02,a11,b0,b1,b2,b3;
+
+ a02 = d[0] - e[2];
+ a11 = d[1] + e[3];
+
+ b0 = C[1]*a02 + C[0]*a11;
+ b1 = C[1]*a11 - C[0]*a02;
+
+ b2 = d[0] + e[ 2];
+ b3 = d[1] - e[ 3];
+
+ d[0] = b2 + b0;
+ d[1] = b3 + b1;
+ e[2] = b2 - b0;
+ e[3] = b1 - b3;
+
+ a02 = d[2] - e[0];
+ a11 = d[3] + e[1];
+
+ b0 = C[3]*a02 + C[2]*a11;
+ b1 = C[3]*a11 - C[2]*a02;
+
+ b2 = d[2] + e[ 0];
+ b3 = d[3] - e[ 1];
+
+ d[2] = b2 + b0;
+ d[3] = b3 + b1;
+ e[0] = b2 - b0;
+ e[1] = b1 - b3;
+
+ C += 4;
+ d += 4;
+ e -= 4;
+ }
+ }
+
+ // data must be in buf2
+
+
+ // step 8+decode (paper output is X, now buffer)
+ // this generates pairs of data a la 8 and pushes them directly through
+ // the decode kernel (pushing rather than pulling) to avoid having
+ // to make another pass later
+
+ // this cannot POSSIBLY be in place, so we refer to the buffers directly
+
+ {
+ float *d0,*d1,*d2,*d3;
+
+ float *B = f->B[blocktype] + n2 - 8;
+ float *e = buf2 + n2 - 8;
+ d0 = &buffer[0];
+ d1 = &buffer[n2-4];
+ d2 = &buffer[n2];
+ d3 = &buffer[n-4];
+ while (e >= v) {
+ float p0,p1,p2,p3;
+
+ p3 = e[6]*B[7] - e[7]*B[6];
+ p2 = -e[6]*B[6] - e[7]*B[7];
+
+ d0[0] = p3;
+ d1[3] = - p3;
+ d2[0] = p2;
+ d3[3] = p2;
+
+ p1 = e[4]*B[5] - e[5]*B[4];
+ p0 = -e[4]*B[4] - e[5]*B[5];
+
+ d0[1] = p1;
+ d1[2] = - p1;
+ d2[1] = p0;
+ d3[2] = p0;
+
+ p3 = e[2]*B[3] - e[3]*B[2];
+ p2 = -e[2]*B[2] - e[3]*B[3];
+
+ d0[2] = p3;
+ d1[1] = - p3;
+ d2[2] = p2;
+ d3[1] = p2;
+
+ p1 = e[0]*B[1] - e[1]*B[0];
+ p0 = -e[0]*B[0] - e[1]*B[1];
+
+ d0[3] = p1;
+ d1[0] = - p1;
+ d2[3] = p0;
+ d3[0] = p0;
+
+ B -= 8;
+ e -= 8;
+ d0 += 4;
+ d2 += 4;
+ d1 -= 4;
+ d3 -= 4;
+ }
+ }
+
+ temp_free(f,buf2);
+ temp_alloc_restore(f,save_point);
+}
+
+#if 0
+// this is the original version of the above code, if you want to optimize it from scratch
+void inverse_mdct_naive(float *buffer, int n)
+{
+ float s;
+ float A[1 << 12], B[1 << 12], C[1 << 11];
+ int i,k,k2,k4, n2 = n >> 1, n4 = n >> 2, n8 = n >> 3, l;
+ int n3_4 = n - n4, ld;
+ // how can they claim this only uses N words?!
+ // oh, because they're only used sparsely, whoops
+ float u[1 << 13], X[1 << 13], v[1 << 13], w[1 << 13];
+ // set up twiddle factors
+
+ for (k=k2=0; k < n4; ++k,k2+=2) {
+ A[k2 ] = (float) cos(4*k*M_PI/n);
+ A[k2+1] = (float) -sin(4*k*M_PI/n);
+ B[k2 ] = (float) cos((k2+1)*M_PI/n/2);
+ B[k2+1] = (float) sin((k2+1)*M_PI/n/2);
+ }
+ for (k=k2=0; k < n8; ++k,k2+=2) {
+ C[k2 ] = (float) cos(2*(k2+1)*M_PI/n);
+ C[k2+1] = (float) -sin(2*(k2+1)*M_PI/n);
+ }
+
+ // IMDCT algorithm from "The use of multirate filter banks for coding of high quality digital audio"
+ // Note there are bugs in that pseudocode, presumably due to them attempting
+ // to rename the arrays nicely rather than representing the way their actual
+ // implementation bounces buffers back and forth. As a result, even in the
+ // "some formulars corrected" version, a direct implementation fails. These
+ // are noted below as "paper bug".
+
+ // copy and reflect spectral data
+ for (k=0; k < n2; ++k) u[k] = buffer[k];
+ for ( ; k < n ; ++k) u[k] = -buffer[n - k - 1];
+ // kernel from paper
+ // step 1
+ for (k=k2=k4=0; k < n4; k+=1, k2+=2, k4+=4) {
+ v[n-k4-1] = (u[k4] - u[n-k4-1]) * A[k2] - (u[k4+2] - u[n-k4-3])*A[k2+1];
+ v[n-k4-3] = (u[k4] - u[n-k4-1]) * A[k2+1] + (u[k4+2] - u[n-k4-3])*A[k2];
+ }
+ // step 2
+ for (k=k4=0; k < n8; k+=1, k4+=4) {
+ w[n2+3+k4] = v[n2+3+k4] + v[k4+3];
+ w[n2+1+k4] = v[n2+1+k4] + v[k4+1];
+ w[k4+3] = (v[n2+3+k4] - v[k4+3])*A[n2-4-k4] - (v[n2+1+k4]-v[k4+1])*A[n2-3-k4];
+ w[k4+1] = (v[n2+1+k4] - v[k4+1])*A[n2-4-k4] + (v[n2+3+k4]-v[k4+3])*A[n2-3-k4];
+ }
+ // step 3
+ ld = ilog(n) - 1; // ilog is off-by-one from normal definitions
+ for (l=0; l < ld-3; ++l) {
+ int k0 = n >> (l+2), k1 = 1 << (l+3);
+ int rlim = n >> (l+4), r4, r;
+ int s2lim = 1 << (l+2), s2;
+ for (r=r4=0; r < rlim; r4+=4,++r) {
+ for (s2=0; s2 < s2lim; s2+=2) {
+ u[n-1-k0*s2-r4] = w[n-1-k0*s2-r4] + w[n-1-k0*(s2+1)-r4];
+ u[n-3-k0*s2-r4] = w[n-3-k0*s2-r4] + w[n-3-k0*(s2+1)-r4];
+ u[n-1-k0*(s2+1)-r4] = (w[n-1-k0*s2-r4] - w[n-1-k0*(s2+1)-r4]) * A[r*k1]
+ - (w[n-3-k0*s2-r4] - w[n-3-k0*(s2+1)-r4]) * A[r*k1+1];
+ u[n-3-k0*(s2+1)-r4] = (w[n-3-k0*s2-r4] - w[n-3-k0*(s2+1)-r4]) * A[r*k1]
+ + (w[n-1-k0*s2-r4] - w[n-1-k0*(s2+1)-r4]) * A[r*k1+1];
+ }
+ }
+ if (l+1 < ld-3) {
+ // paper bug: ping-ponging of u&w here is omitted
+ memcpy(w, u, sizeof(u));
+ }
+ }
+
+ // step 4
+ for (i=0; i < n8; ++i) {
+ int j = bit_reverse(i) >> (32-ld+3);
+ assert(j < n8);
+ if (i == j) {
+ // paper bug: original code probably swapped in place; if copying,
+ // need to directly copy in this case
+ int i8 = i << 3;
+ v[i8+1] = u[i8+1];
+ v[i8+3] = u[i8+3];
+ v[i8+5] = u[i8+5];
+ v[i8+7] = u[i8+7];
+ } else if (i < j) {
+ int i8 = i << 3, j8 = j << 3;
+ v[j8+1] = u[i8+1], v[i8+1] = u[j8 + 1];
+ v[j8+3] = u[i8+3], v[i8+3] = u[j8 + 3];
+ v[j8+5] = u[i8+5], v[i8+5] = u[j8 + 5];
+ v[j8+7] = u[i8+7], v[i8+7] = u[j8 + 7];
+ }
+ }
+ // step 5
+ for (k=0; k < n2; ++k) {
+ w[k] = v[k*2+1];
+ }
+ // step 6
+ for (k=k2=k4=0; k < n8; ++k, k2 += 2, k4 += 4) {
+ u[n-1-k2] = w[k4];
+ u[n-2-k2] = w[k4+1];
+ u[n3_4 - 1 - k2] = w[k4+2];
+ u[n3_4 - 2 - k2] = w[k4+3];
+ }
+ // step 7
+ for (k=k2=0; k < n8; ++k, k2 += 2) {
+ v[n2 + k2 ] = ( u[n2 + k2] + u[n-2-k2] + C[k2+1]*(u[n2+k2]-u[n-2-k2]) + C[k2]*(u[n2+k2+1]+u[n-2-k2+1]))/2;
+ v[n-2 - k2] = ( u[n2 + k2] + u[n-2-k2] - C[k2+1]*(u[n2+k2]-u[n-2-k2]) - C[k2]*(u[n2+k2+1]+u[n-2-k2+1]))/2;
+ v[n2+1+ k2] = ( u[n2+1+k2] - u[n-1-k2] + C[k2+1]*(u[n2+1+k2]+u[n-1-k2]) - C[k2]*(u[n2+k2]-u[n-2-k2]))/2;
+ v[n-1 - k2] = (-u[n2+1+k2] + u[n-1-k2] + C[k2+1]*(u[n2+1+k2]+u[n-1-k2]) - C[k2]*(u[n2+k2]-u[n-2-k2]))/2;
+ }
+ // step 8
+ for (k=k2=0; k < n4; ++k,k2 += 2) {
+ X[k] = v[k2+n2]*B[k2 ] + v[k2+1+n2]*B[k2+1];
+ X[n2-1-k] = v[k2+n2]*B[k2+1] - v[k2+1+n2]*B[k2 ];
+ }
+
+ // decode kernel to output
+ // determined the following value experimentally
+ // (by first figuring out what made inverse_mdct_slow work); then matching that here
+ // (probably vorbis encoder premultiplies by n or n/2, to save it on the decoder?)
+ s = 0.5; // theoretically would be n4
+
+ // [[[ note! the s value of 0.5 is compensated for by the B[] in the current code,
+ // so it needs to use the "old" B values to behave correctly, or else
+ // set s to 1.0 ]]]
+ for (i=0; i < n4 ; ++i) buffer[i] = s * X[i+n4];
+ for ( ; i < n3_4; ++i) buffer[i] = -s * X[n3_4 - i - 1];
+ for ( ; i < n ; ++i) buffer[i] = -s * X[i - n3_4];
+}
+#endif
+
+static float *get_window(vorb *f, int len)
+{
+ len <<= 1;
+ if (len == f->blocksize_0) return f->window[0];
+ if (len == f->blocksize_1) return f->window[1];
+ assert(0);
+ return NULL;
+}
+
+#ifndef STB_VORBIS_NO_DEFER_FLOOR
+typedef int16 YTYPE;
+#else
+typedef int YTYPE;
+#endif
+static int do_floor(vorb *f, Mapping *map, int i, int n, float *target, YTYPE *finalY, uint8 *step2_flag)
+{
+ int n2 = n >> 1;
+ int s = map->chan[i].mux, floor;
+ floor = map->submap_floor[s];
+ if (f->floor_types[floor] == 0) {
+ return error(f, VORBIS_invalid_stream);
+ } else {
+ Floor1 *g = &f->floor_config[floor].floor1;
+ int j,q;
+ int lx = 0, ly = finalY[0] * g->floor1_multiplier;
+ for (q=1; q < g->values; ++q) {
+ j = g->sorted_order[q];
+ #ifndef STB_VORBIS_NO_DEFER_FLOOR
+ if (finalY[j] >= 0)
+ #else
+ if (step2_flag[j])
+ #endif
+ {
+ int hy = finalY[j] * g->floor1_multiplier;
+ int hx = g->Xlist[j];
+ if (lx != hx)
+ draw_line(target, lx,ly, hx,hy, n2);
+ CHECK(f);
+ lx = hx, ly = hy;
+ }
+ }
+ if (lx < n2) {
+ // optimization of: draw_line(target, lx,ly, n,ly, n2);
+ for (j=lx; j < n2; ++j)
+ LINE_OP(target[j], inverse_db_table[ly]);
+ CHECK(f);
+ }
+ }
+ return TRUE;
+}
+
+// The meaning of "left" and "right"
+//
+// For a given frame:
+// we compute samples from 0..n
+// window_center is n/2
+// we'll window and mix the samples from left_start to left_end with data from the previous frame
+// all of the samples from left_end to right_start can be output without mixing; however,
+// this interval is 0-length except when transitioning between short and long frames
+// all of the samples from right_start to right_end need to be mixed with the next frame,
+// which we don't have, so those get saved in a buffer
+// frame N's right_end-right_start, the number of samples to mix with the next frame,
+// has to be the same as frame N+1's left_end-left_start (which they are by
+// construction)
+
+static int vorbis_decode_initial(vorb *f, int *p_left_start, int *p_left_end, int *p_right_start, int *p_right_end, int *mode)
+{
+ Mode *m;
+ int i, n, prev, next, window_center;
+ f->channel_buffer_start = f->channel_buffer_end = 0;
+
+ retry:
+ if (f->eof) return FALSE;
+ if (!maybe_start_packet(f))
+ return FALSE;
+ // check packet type
+ if (get_bits(f,1) != 0) {
+ if (IS_PUSH_MODE(f))
+ return error(f,VORBIS_bad_packet_type);
+ while (EOP != get8_packet(f));
+ goto retry;
+ }
+
+ if (f->alloc.alloc_buffer)
+ assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
+
+ i = get_bits(f, ilog(f->mode_count-1));
+ if (i == EOP) return FALSE;
+ if (i >= f->mode_count) return FALSE;
+ *mode = i;
+ m = f->mode_config + i;
+ if (m->blockflag) {
+ n = f->blocksize_1;
+ prev = get_bits(f,1);
+ next = get_bits(f,1);
+ } else {
+ prev = next = 0;
+ n = f->blocksize_0;
+ }
+
+// WINDOWING
+
+ window_center = n >> 1;
+ if (m->blockflag && !prev) {
+ *p_left_start = (n - f->blocksize_0) >> 2;
+ *p_left_end = (n + f->blocksize_0) >> 2;
+ } else {
+ *p_left_start = 0;
+ *p_left_end = window_center;
+ }
+ if (m->blockflag && !next) {
+ *p_right_start = (n*3 - f->blocksize_0) >> 2;
+ *p_right_end = (n*3 + f->blocksize_0) >> 2;
+ } else {
+ *p_right_start = window_center;
+ *p_right_end = n;
+ }
+
+ return TRUE;
+}
+
+static int vorbis_decode_packet_rest(vorb *f, int *len, Mode *m, int left_start, int left_end, int right_start, int right_end, int *p_left)
+{
+ Mapping *map;
+ int i,j,k,n,n2;
+ int zero_channel[256];
+ int really_zero_channel[256];
+
+// WINDOWING
+
+ n = f->blocksize[m->blockflag];
+ map = &f->mapping[m->mapping];
+
+// FLOORS
+ n2 = n >> 1;
+
+ CHECK(f);
+
+ for (i=0; i < f->channels; ++i) {
+ int s = map->chan[i].mux, floor;
+ zero_channel[i] = FALSE;
+ floor = map->submap_floor[s];
+ if (f->floor_types[floor] == 0) {
+ return error(f, VORBIS_invalid_stream);
+ } else {
+ Floor1 *g = &f->floor_config[floor].floor1;
+ if (get_bits(f, 1)) {
+ short *finalY;
+ uint8 step2_flag[256];
+ static int range_list[4] = { 256, 128, 86, 64 };
+ int range = range_list[g->floor1_multiplier-1];
+ int offset = 2;
+ finalY = f->finalY[i];
+ finalY[0] = get_bits(f, ilog(range)-1);
+ finalY[1] = get_bits(f, ilog(range)-1);
+ for (j=0; j < g->partitions; ++j) {
+ int pclass = g->partition_class_list[j];
+ int cdim = g->class_dimensions[pclass];
+ int cbits = g->class_subclasses[pclass];
+ int csub = (1 << cbits)-1;
+ int cval = 0;
+ if (cbits) {
+ Codebook *c = f->codebooks + g->class_masterbooks[pclass];
+ DECODE(cval,f,c);
+ }
+ for (k=0; k < cdim; ++k) {
+ int book = g->subclass_books[pclass][cval & csub];
+ cval = cval >> cbits;
+ if (book >= 0) {
+ int temp;
+ Codebook *c = f->codebooks + book;
+ DECODE(temp,f,c);
+ finalY[offset++] = temp;
+ } else
+ finalY[offset++] = 0;
+ }
+ }
+ if (f->valid_bits == INVALID_BITS) goto error; // behavior according to spec
+ step2_flag[0] = step2_flag[1] = 1;
+ for (j=2; j < g->values; ++j) {
+ int low, high, pred, highroom, lowroom, room, val;
+ low = g->neighbors[j][0];
+ high = g->neighbors[j][1];
+ //neighbors(g->Xlist, j, &low, &high);
+ pred = predict_point(g->Xlist[j], g->Xlist[low], g->Xlist[high], finalY[low], finalY[high]);
+ val = finalY[j];
+ highroom = range - pred;
+ lowroom = pred;
+ if (highroom < lowroom)
+ room = highroom * 2;
+ else
+ room = lowroom * 2;
+ if (val) {
+ step2_flag[low] = step2_flag[high] = 1;
+ step2_flag[j] = 1;
+ if (val >= room)
+ if (highroom > lowroom)
+ finalY[j] = val - lowroom + pred;
+ else
+ finalY[j] = pred - val + highroom - 1;
+ else
+ if (val & 1)
+ finalY[j] = pred - ((val+1)>>1);
+ else
+ finalY[j] = pred + (val>>1);
+ } else {
+ step2_flag[j] = 0;
+ finalY[j] = pred;
+ }
+ }
+
+#ifdef STB_VORBIS_NO_DEFER_FLOOR
+ do_floor(f, map, i, n, f->floor_buffers[i], finalY, step2_flag);
+#else
+ // defer final floor computation until _after_ residue
+ for (j=0; j < g->values; ++j) {
+ if (!step2_flag[j])
+ finalY[j] = -1;
+ }
+#endif
+ } else {
+ error:
+ zero_channel[i] = TRUE;
+ }
+ // So we just defer everything else to later
+
+ // at this point we've decoded the floor into buffer
+ }
+ }
+ CHECK(f);
+ // at this point we've decoded all floors
+
+ if (f->alloc.alloc_buffer)
+ assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
+
+ // re-enable coupled channels if necessary
+ memcpy(really_zero_channel, zero_channel, sizeof(really_zero_channel[0]) * f->channels);
+ for (i=0; i < map->coupling_steps; ++i)
+ if (!zero_channel[map->chan[i].magnitude] || !zero_channel[map->chan[i].angle]) {
+ zero_channel[map->chan[i].magnitude] = zero_channel[map->chan[i].angle] = FALSE;
+ }
+
+ CHECK(f);
+// RESIDUE DECODE
+ for (i=0; i < map->submaps; ++i) {
+ float *residue_buffers[STB_VORBIS_MAX_CHANNELS];
+ int r;
+ uint8 do_not_decode[256];
+ int ch = 0;
+ for (j=0; j < f->channels; ++j) {
+ if (map->chan[j].mux == i) {
+ if (zero_channel[j]) {
+ do_not_decode[ch] = TRUE;
+ residue_buffers[ch] = NULL;
+ } else {
+ do_not_decode[ch] = FALSE;
+ residue_buffers[ch] = f->channel_buffers[j];
+ }
+ ++ch;
+ }
+ }
+ r = map->submap_residue[i];
+ decode_residue(f, residue_buffers, ch, n2, r, do_not_decode);
+ }
+
+ if (f->alloc.alloc_buffer)
+ assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
+ CHECK(f);
+
+// INVERSE COUPLING
+ for (i = map->coupling_steps-1; i >= 0; --i) {
+ int n2 = n >> 1;
+ float *m = f->channel_buffers[map->chan[i].magnitude];
+ float *a = f->channel_buffers[map->chan[i].angle ];
+ for (j=0; j < n2; ++j) {
+ float a2,m2;
+ if (m[j] > 0)
+ if (a[j] > 0)
+ m2 = m[j], a2 = m[j] - a[j];
+ else
+ a2 = m[j], m2 = m[j] + a[j];
+ else
+ if (a[j] > 0)
+ m2 = m[j], a2 = m[j] + a[j];
+ else
+ a2 = m[j], m2 = m[j] - a[j];
+ m[j] = m2;
+ a[j] = a2;
+ }
+ }
+ CHECK(f);
+
+ // finish decoding the floors
+#ifndef STB_VORBIS_NO_DEFER_FLOOR
+ for (i=0; i < f->channels; ++i) {
+ if (really_zero_channel[i]) {
+ memset(f->channel_buffers[i], 0, sizeof(*f->channel_buffers[i]) * n2);
+ } else {
+ do_floor(f, map, i, n, f->channel_buffers[i], f->finalY[i], NULL);
+ }
+ }
+#else
+ for (i=0; i < f->channels; ++i) {
+ if (really_zero_channel[i]) {
+ memset(f->channel_buffers[i], 0, sizeof(*f->channel_buffers[i]) * n2);
+ } else {
+ for (j=0; j < n2; ++j)
+ f->channel_buffers[i][j] *= f->floor_buffers[i][j];
+ }
+ }
+#endif
+
+// INVERSE MDCT
+ CHECK(f);
+ for (i=0; i < f->channels; ++i)
+ inverse_mdct(f->channel_buffers[i], n, f, m->blockflag);
+ CHECK(f);
+
+ // this shouldn't be necessary, unless we exited on an error
+ // and want to flush to get to the next packet
+ flush_packet(f);
+
+ if (f->first_decode) {
+ // assume we start so first non-discarded sample is sample 0
+ // this isn't to spec, but spec would require us to read ahead
+ // and decode the size of all current frames--could be done,
+ // but presumably it's not a commonly used feature
+ f->current_loc = -n2; // start of first frame is positioned for discard
+ // we might have to discard samples "from" the next frame too,
+ // if we're lapping a large block then a small at the start?
+ f->discard_samples_deferred = n - right_end;
+ f->current_loc_valid = TRUE;
+ f->first_decode = FALSE;
+ } else if (f->discard_samples_deferred) {
+ if (f->discard_samples_deferred >= right_start - left_start) {
+ f->discard_samples_deferred -= (right_start - left_start);
+ left_start = right_start;
+ *p_left = left_start;
+ } else {
+ left_start += f->discard_samples_deferred;
+ *p_left = left_start;
+ f->discard_samples_deferred = 0;
+ }
+ } else if (f->previous_length == 0 && f->current_loc_valid) {
+ // we're recovering from a seek... that means we're going to discard
+ // the samples from this packet even though we know our position from
+ // the last page header, so we need to update the position based on
+ // the discarded samples here
+ // but wait, the code below is going to add this in itself even
+ // on a discard, so we don't need to do it here...
+ }
+
+ // check if we have ogg information about the sample # for this packet
+ if (f->last_seg_which == f->end_seg_with_known_loc) {
+ // if we have a valid current loc, and this is final:
+ if (f->current_loc_valid && (f->page_flag & PAGEFLAG_last_page)) {
+ uint32 current_end = f->known_loc_for_packet - (n-right_end);
+ // then let's infer the size of the (probably) short final frame
+ if (current_end < f->current_loc + (right_end-left_start)) {
+ if (current_end < f->current_loc) {
+ // negative truncation, that's impossible!
+ *len = 0;
+ } else {
+ *len = current_end - f->current_loc;
+ }
+ *len += left_start;
+ if (*len > right_end) *len = right_end; // this should never happen
+ f->current_loc += *len;
+ return TRUE;
+ }
+ }
+ // otherwise, just set our sample loc
+ // guess that the ogg granule pos refers to the _middle_ of the
+ // last frame?
+ // set f->current_loc to the position of left_start
+ f->current_loc = f->known_loc_for_packet - (n2-left_start);
+ f->current_loc_valid = TRUE;
+ }
+ if (f->current_loc_valid)
+ f->current_loc += (right_start - left_start);
+
+ if (f->alloc.alloc_buffer)
+ assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
+ *len = right_end; // ignore samples after the window goes to 0
+ CHECK(f);
+
+ return TRUE;
+}
+
+static int vorbis_decode_packet(vorb *f, int *len, int *p_left, int *p_right)
+{
+ int mode, left_end, right_end;
+ if (!vorbis_decode_initial(f, p_left, &left_end, p_right, &right_end, &mode)) return 0;
+ return vorbis_decode_packet_rest(f, len, f->mode_config + mode, *p_left, left_end, *p_right, right_end, p_left);
+}
+
+static int vorbis_finish_frame(stb_vorbis *f, int len, int left, int right)
+{
+ int prev,i,j;
+ // we use right&left (the start of the right- and left-window sin()-regions)
+ // to determine how much to return, rather than inferring from the rules
+ // (same result, clearer code); 'left' indicates where our sin() window
+ // starts, therefore where the previous window's right edge starts, and
+ // therefore where to start mixing from the previous buffer. 'right'
+ // indicates where our sin() ending-window starts, therefore that's where
+ // we start saving, and where our returned-data ends.
+
+ // mixin from previous window
+ if (f->previous_length) {
+ int i,j, n = f->previous_length;
+ float *w = get_window(f, n);
+ for (i=0; i < f->channels; ++i) {
+ for (j=0; j < n; ++j)
+ f->channel_buffers[i][left+j] =
+ f->channel_buffers[i][left+j]*w[ j] +
+ f->previous_window[i][ j]*w[n-1-j];
+ }
+ }
+
+ prev = f->previous_length;
+
+ // last half of this data becomes previous window
+ f->previous_length = len - right;
+
+ // @OPTIMIZE: could avoid this copy by double-buffering the
+ // output (flipping previous_window with channel_buffers), but
+ // then previous_window would have to be 2x as large, and
+ // channel_buffers couldn't be temp mem (although they're NOT
+ // currently temp mem, they could be (unless we want to level
+ // performance by spreading out the computation))
+ for (i=0; i < f->channels; ++i)
+ for (j=0; right+j < len; ++j)
+ f->previous_window[i][j] = f->channel_buffers[i][right+j];
+
+ if (!prev)
+ // there was no previous packet, so this data isn't valid...
+ // this isn't entirely true, only the would-have-overlapped data
+ // isn't valid, but this seems to be what the spec requires
+ return 0;
+
+ // truncate a short frame
+ if (len < right) right = len;
+
+ f->samples_output += right-left;
+
+ return right - left;
+}
+
+static void vorbis_pump_first_frame(stb_vorbis *f)
+{
+ int len, right, left;
+ if (vorbis_decode_packet(f, &len, &left, &right))
+ vorbis_finish_frame(f, len, left, right);
+}
+
+#ifndef STB_VORBIS_NO_PUSHDATA_API
+static int is_whole_packet_present(stb_vorbis *f, int end_page)
+{
+ // make sure that we have the packet available before continuing...
+ // this requires a full ogg parse, but we know we can fetch from f->stream
+
+ // instead of coding this out explicitly, we could save the current read state,
+ // read the next packet with get8() until end-of-packet, check f->eof, then
+ // reset the state? but that would be slower, esp. since we'd have over 256 bytes
+ // of state to restore (primarily the page segment table)
+
+ int s = f->next_seg, first = TRUE;
+ uint8 *p = f->stream;
+
+ if (s != -1) { // if we're not starting the packet with a 'continue on next page' flag
+ for (; s < f->segment_count; ++s) {
+ p += f->segments[s];
+ if (f->segments[s] < 255) // stop at first short segment
+ break;
+ }
+ // either this continues, or it ends it...
+ if (end_page)
+ if (s < f->segment_count-1) return error(f, VORBIS_invalid_stream);
+ if (s == f->segment_count)
+ s = -1; // set 'crosses page' flag
+ if (p > f->stream_end) return error(f, VORBIS_need_more_data);
+ first = FALSE;
+ }
+ for (; s == -1;) {
+ uint8 *q;
+ int n;
+
+ // check that we have the page header ready
+ if (p + 26 >= f->stream_end) return error(f, VORBIS_need_more_data);
+ // validate the page
+ if (memcmp(p, ogg_page_header, 4)) return error(f, VORBIS_invalid_stream);
+ if (p[4] != 0) return error(f, VORBIS_invalid_stream);
+ if (first) { // the first segment must NOT have 'continued_packet', later ones MUST
+ if (f->previous_length)
+ if ((p[5] & PAGEFLAG_continued_packet)) return error(f, VORBIS_invalid_stream);
+ // if no previous length, we're resynching, so we can come in on a continued-packet,
+ // which we'll just drop
+ } else {
+ if (!(p[5] & PAGEFLAG_continued_packet)) return error(f, VORBIS_invalid_stream);
+ }
+ n = p[26]; // segment counts
+ q = p+27; // q points to segment table
+ p = q + n; // advance past header
+ // make sure we've read the segment table
+ if (p > f->stream_end) return error(f, VORBIS_need_more_data);
+ for (s=0; s < n; ++s) {
+ p += q[s];
+ if (q[s] < 255)
+ break;
+ }
+ if (end_page)
+ if (s < n-1) return error(f, VORBIS_invalid_stream);
+ if (s == n)
+ s = -1; // set 'crosses page' flag
+ if (p > f->stream_end) return error(f, VORBIS_need_more_data);
+ first = FALSE;
+ }
+ return TRUE;
+}
+#endif // !STB_VORBIS_NO_PUSHDATA_API
+
+static int start_decoder(vorb *f)
+{
+ uint8 header[6], x,y;
+ int len,i,j,k, max_submaps = 0;
+ int longest_floorlist=0;
+
+ // first page, first packet
+
+ if (!start_page(f)) return FALSE;
+ // validate page flag
+ if (!(f->page_flag & PAGEFLAG_first_page)) return error(f, VORBIS_invalid_first_page);
+ if (f->page_flag & PAGEFLAG_last_page) return error(f, VORBIS_invalid_first_page);
+ if (f->page_flag & PAGEFLAG_continued_packet) return error(f, VORBIS_invalid_first_page);
+ // check for expected packet length
+ if (f->segment_count != 1) return error(f, VORBIS_invalid_first_page);
+ if (f->segments[0] != 30) return error(f, VORBIS_invalid_first_page);
+ // read packet
+ // check packet header
+ if (get8(f) != VORBIS_packet_id) return error(f, VORBIS_invalid_first_page);
+ if (!getn(f, header, 6)) return error(f, VORBIS_unexpected_eof);
+ if (!vorbis_validate(header)) return error(f, VORBIS_invalid_first_page);
+ // vorbis_version
+ if (get32(f) != 0) return error(f, VORBIS_invalid_first_page);
+ f->channels = get8(f); if (!f->channels) return error(f, VORBIS_invalid_first_page);
+ if (f->channels > STB_VORBIS_MAX_CHANNELS) return error(f, VORBIS_too_many_channels);
+ f->sample_rate = get32(f); if (!f->sample_rate) return error(f, VORBIS_invalid_first_page);
+ get32(f); // bitrate_maximum
+ get32(f); // bitrate_nominal
+ get32(f); // bitrate_minimum
+ x = get8(f);
+ {
+ int log0,log1;
+ log0 = x & 15;
+ log1 = x >> 4;
+ f->blocksize_0 = 1 << log0;
+ f->blocksize_1 = 1 << log1;
+ if (log0 < 6 || log0 > 13) return error(f, VORBIS_invalid_setup);
+ if (log1 < 6 || log1 > 13) return error(f, VORBIS_invalid_setup);
+ if (log0 > log1) return error(f, VORBIS_invalid_setup);
+ }
+
+ // framing_flag
+ x = get8(f);
+ if (!(x & 1)) return error(f, VORBIS_invalid_first_page);
+
+ // second packet!
+ if (!start_page(f)) return FALSE;
+
+ if (!start_packet(f)) return FALSE;
+ do {
+ len = next_segment(f);
+ skip(f, len);
+ f->bytes_in_seg = 0;
+ } while (len);
+
+ // third packet!
+ if (!start_packet(f)) return FALSE;
+
+ #ifndef STB_VORBIS_NO_PUSHDATA_API
+ if (IS_PUSH_MODE(f)) {
+ if (!is_whole_packet_present(f, TRUE)) {
+ // convert error in ogg header to write type
+ if (f->error == VORBIS_invalid_stream)
+ f->error = VORBIS_invalid_setup;
+ return FALSE;
+ }
+ }
+ #endif
+
+ crc32_init(); // always init it, to avoid multithread race conditions
+
+ if (get8_packet(f) != VORBIS_packet_setup) return error(f, VORBIS_invalid_setup);
+ for (i=0; i < 6; ++i) header[i] = get8_packet(f);
+ if (!vorbis_validate(header)) return error(f, VORBIS_invalid_setup);
+
+ // codebooks
+
+ f->codebook_count = get_bits(f,8) + 1;
+ f->codebooks = (Codebook *) setup_malloc(f, sizeof(*f->codebooks) * f->codebook_count);
+ if (f->codebooks == NULL) return error(f, VORBIS_outofmem);
+ memset(f->codebooks, 0, sizeof(*f->codebooks) * f->codebook_count);
+ for (i=0; i < f->codebook_count; ++i) {
+ uint32 *values;
+ int ordered, sorted_count;
+ int total=0;
+ uint8 *lengths;
+ Codebook *c = f->codebooks+i;
+ CHECK(f);
+ x = get_bits(f, 8); if (x != 0x42) return error(f, VORBIS_invalid_setup);
+ x = get_bits(f, 8); if (x != 0x43) return error(f, VORBIS_invalid_setup);
+ x = get_bits(f, 8); if (x != 0x56) return error(f, VORBIS_invalid_setup);
+ x = get_bits(f, 8);
+ c->dimensions = (get_bits(f, 8)<<8) + x;
+ x = get_bits(f, 8);
+ y = get_bits(f, 8);
+ c->entries = (get_bits(f, 8)<<16) + (y<<8) + x;
+ ordered = get_bits(f,1);
+ c->sparse = ordered ? 0 : get_bits(f,1);
+
+ if (c->dimensions == 0 && c->entries != 0) return error(f, VORBIS_invalid_setup);
+
+ if (c->sparse)
+ lengths = (uint8 *) setup_temp_malloc(f, c->entries);
+ else
+ lengths = c->codeword_lengths = (uint8 *) setup_malloc(f, c->entries);
+
+ if (!lengths) return error(f, VORBIS_outofmem);
+
+ if (ordered) {
+ int current_entry = 0;
+ int current_length = get_bits(f,5) + 1;
+ while (current_entry < c->entries) {
+ int limit = c->entries - current_entry;
+ int n = get_bits(f, ilog(limit));
+ if (current_entry + n > (int) c->entries) { return error(f, VORBIS_invalid_setup); }
+ memset(lengths + current_entry, current_length, n);
+ current_entry += n;
+ ++current_length;
+ }
+ } else {
+ for (j=0; j < c->entries; ++j) {
+ int present = c->sparse ? get_bits(f,1) : 1;
+ if (present) {
+ lengths[j] = get_bits(f, 5) + 1;
+ ++total;
+ if (lengths[j] == 32)
+ return error(f, VORBIS_invalid_setup);
+ } else {
+ lengths[j] = NO_CODE;
+ }
+ }
+ }
+
+ if (c->sparse && total >= c->entries >> 2) {
+ // convert sparse items to non-sparse!
+ if (c->entries > (int) f->setup_temp_memory_required)
+ f->setup_temp_memory_required = c->entries;
+
+ c->codeword_lengths = (uint8 *) setup_malloc(f, c->entries);
+ if (c->codeword_lengths == NULL) return error(f, VORBIS_outofmem);
+ memcpy(c->codeword_lengths, lengths, c->entries);
+ setup_temp_free(f, lengths, c->entries); // note this is only safe if there have been no intervening temp mallocs!
+ lengths = c->codeword_lengths;
+ c->sparse = 0;
+ }
+
+ // compute the size of the sorted tables
+ if (c->sparse) {
+ sorted_count = total;
+ } else {
+ sorted_count = 0;
+ #ifndef STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
+ for (j=0; j < c->entries; ++j)
+ if (lengths[j] > STB_VORBIS_FAST_HUFFMAN_LENGTH && lengths[j] != NO_CODE)
+ ++sorted_count;
+ #endif
+ }
+
+ c->sorted_entries = sorted_count;
+ values = NULL;
+
+ CHECK(f);
+ if (!c->sparse) {
+ c->codewords = (uint32 *) setup_malloc(f, sizeof(c->codewords[0]) * c->entries);
+ if (!c->codewords) return error(f, VORBIS_outofmem);
+ } else {
+ unsigned int size;
+ if (c->sorted_entries) {
+ c->codeword_lengths = (uint8 *) setup_malloc(f, c->sorted_entries);
+ if (!c->codeword_lengths) return error(f, VORBIS_outofmem);
+ c->codewords = (uint32 *) setup_temp_malloc(f, sizeof(*c->codewords) * c->sorted_entries);
+ if (!c->codewords) return error(f, VORBIS_outofmem);
+ values = (uint32 *) setup_temp_malloc(f, sizeof(*values) * c->sorted_entries);
+ if (!values) return error(f, VORBIS_outofmem);
+ }
+ size = c->entries + (sizeof(*c->codewords) + sizeof(*values)) * c->sorted_entries;
+ if (size > f->setup_temp_memory_required)
+ f->setup_temp_memory_required = size;
+ }
+
+ if (!compute_codewords(c, lengths, c->entries, values)) {
+ if (c->sparse) setup_temp_free(f, values, 0);
+ return error(f, VORBIS_invalid_setup);
+ }
+
+ if (c->sorted_entries) {
+ // allocate an extra slot for sentinels
+ c->sorted_codewords = (uint32 *) setup_malloc(f, sizeof(*c->sorted_codewords) * (c->sorted_entries+1));
+ if (c->sorted_codewords == NULL) return error(f, VORBIS_outofmem);
+ // allocate an extra slot at the front so that c->sorted_values[-1] is defined
+ // so that we can catch that case without an extra if
+ c->sorted_values = ( int *) setup_malloc(f, sizeof(*c->sorted_values ) * (c->sorted_entries+1));
+ if (c->sorted_values == NULL) return error(f, VORBIS_outofmem);
+ ++c->sorted_values;
+ c->sorted_values[-1] = -1;
+ compute_sorted_huffman(c, lengths, values);
+ }
+
+ if (c->sparse) {
+ setup_temp_free(f, values, sizeof(*values)*c->sorted_entries);
+ setup_temp_free(f, c->codewords, sizeof(*c->codewords)*c->sorted_entries);
+ setup_temp_free(f, lengths, c->entries);
+ c->codewords = NULL;
+ }
+
+ compute_accelerated_huffman(c);
+
+ CHECK(f);
+ c->lookup_type = get_bits(f, 4);
+ if (c->lookup_type > 2) return error(f, VORBIS_invalid_setup);
+ if (c->lookup_type > 0) {
+ uint16 *mults;
+ c->minimum_value = float32_unpack(get_bits(f, 32));
+ c->delta_value = float32_unpack(get_bits(f, 32));
+ c->value_bits = get_bits(f, 4)+1;
+ c->sequence_p = get_bits(f,1);
+ if (c->lookup_type == 1) {
+ c->lookup_values = lookup1_values(c->entries, c->dimensions);
+ } else {
+ c->lookup_values = c->entries * c->dimensions;
+ }
+ if (c->lookup_values == 0) return error(f, VORBIS_invalid_setup);
+ mults = (uint16 *) setup_temp_malloc(f, sizeof(mults[0]) * c->lookup_values);
+ if (mults == NULL) return error(f, VORBIS_outofmem);
+ for (j=0; j < (int) c->lookup_values; ++j) {
+ int q = get_bits(f, c->value_bits);
+ if (q == EOP) { setup_temp_free(f,mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_invalid_setup); }
+ mults[j] = q;
+ }
+
+#ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ if (c->lookup_type == 1) {
+ int len, sparse = c->sparse;
+ float last=0;
+ // pre-expand the lookup1-style multiplicands, to avoid a divide in the inner loop
+ if (sparse) {
+ if (c->sorted_entries == 0) goto skip;
+ c->multiplicands = (codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->sorted_entries * c->dimensions);
+ } else
+ c->multiplicands = (codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->entries * c->dimensions);
+ if (c->multiplicands == NULL) { setup_temp_free(f,mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_outofmem); }
+ len = sparse ? c->sorted_entries : c->entries;
+ for (j=0; j < len; ++j) {
+ unsigned int z = sparse ? c->sorted_values[j] : j;
+ unsigned int div=1;
+ for (k=0; k < c->dimensions; ++k) {
+ int off = (z / div) % c->lookup_values;
+ float val = mults[off];
+ val = mults[off]*c->delta_value + c->minimum_value + last;
+ c->multiplicands[j*c->dimensions + k] = val;
+ if (c->sequence_p)
+ last = val;
+ if (k+1 < c->dimensions) {
+ if (div > UINT_MAX / (unsigned int) c->lookup_values) {
+ setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values);
+ return error(f, VORBIS_invalid_setup);
+ }
+ div *= c->lookup_values;
+ }
+ }
+ }
+ c->lookup_type = 2;
+ }
+ else
+#endif
+ {
+ float last=0;
+ CHECK(f);
+ c->multiplicands = (codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->lookup_values);
+ if (c->multiplicands == NULL) { setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_outofmem); }
+ for (j=0; j < (int) c->lookup_values; ++j) {
+ float val = mults[j] * c->delta_value + c->minimum_value + last;
+ c->multiplicands[j] = val;
+ if (c->sequence_p)
+ last = val;
+ }
+ }
+#ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
+ skip:;
+#endif
+ setup_temp_free(f, mults, sizeof(mults[0])*c->lookup_values);
+
+ CHECK(f);
+ }
+ CHECK(f);
+ }
+
+ // time domain transfers (notused)
+
+ x = get_bits(f, 6) + 1;
+ for (i=0; i < x; ++i) {
+ uint32 z = get_bits(f, 16);
+ if (z != 0) return error(f, VORBIS_invalid_setup);
+ }
+
+ // Floors
+ f->floor_count = get_bits(f, 6)+1;
+ f->floor_config = (Floor *) setup_malloc(f, f->floor_count * sizeof(*f->floor_config));
+ if (f->floor_config == NULL) return error(f, VORBIS_outofmem);
+ for (i=0; i < f->floor_count; ++i) {
+ f->floor_types[i] = get_bits(f, 16);
+ if (f->floor_types[i] > 1) return error(f, VORBIS_invalid_setup);
+ if (f->floor_types[i] == 0) {
+ Floor0 *g = &f->floor_config[i].floor0;
+ g->order = get_bits(f,8);
+ g->rate = get_bits(f,16);
+ g->bark_map_size = get_bits(f,16);
+ g->amplitude_bits = get_bits(f,6);
+ g->amplitude_offset = get_bits(f,8);
+ g->number_of_books = get_bits(f,4) + 1;
+ for (j=0; j < g->number_of_books; ++j)
+ g->book_list[j] = get_bits(f,8);
+ return error(f, VORBIS_feature_not_supported);
+ } else {
+ Point p[31*8+2];
+ Floor1 *g = &f->floor_config[i].floor1;
+ int max_class = -1;
+ g->partitions = get_bits(f, 5);
+ for (j=0; j < g->partitions; ++j) {
+ g->partition_class_list[j] = get_bits(f, 4);
+ if (g->partition_class_list[j] > max_class)
+ max_class = g->partition_class_list[j];
+ }
+ for (j=0; j <= max_class; ++j) {
+ g->class_dimensions[j] = get_bits(f, 3)+1;
+ g->class_subclasses[j] = get_bits(f, 2);
+ if (g->class_subclasses[j]) {
+ g->class_masterbooks[j] = get_bits(f, 8);
+ if (g->class_masterbooks[j] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
+ }
+ for (k=0; k < 1 << g->class_subclasses[j]; ++k) {
+ g->subclass_books[j][k] = get_bits(f,8)-1;
+ if (g->subclass_books[j][k] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
+ }
+ }
+ g->floor1_multiplier = get_bits(f,2)+1;
+ g->rangebits = get_bits(f,4);
+ g->Xlist[0] = 0;
+ g->Xlist[1] = 1 << g->rangebits;
+ g->values = 2;
+ for (j=0; j < g->partitions; ++j) {
+ int c = g->partition_class_list[j];
+ for (k=0; k < g->class_dimensions[c]; ++k) {
+ g->Xlist[g->values] = get_bits(f, g->rangebits);
+ ++g->values;
+ }
+ }
+ // precompute the sorting
+ for (j=0; j < g->values; ++j) {
+ p[j].x = g->Xlist[j];
+ p[j].y = j;
+ }
+ qsort(p, g->values, sizeof(p[0]), point_compare);
+ for (j=0; j < g->values; ++j)
+ g->sorted_order[j] = (uint8) p[j].y;
+ // precompute the neighbors
+ for (j=2; j < g->values; ++j) {
+ int low,hi;
+ neighbors(g->Xlist, j, &low,&hi);
+ g->neighbors[j][0] = low;
+ g->neighbors[j][1] = hi;
+ }
+
+ if (g->values > longest_floorlist)
+ longest_floorlist = g->values;
+ }
+ }
+
+ // Residue
+ f->residue_count = get_bits(f, 6)+1;
+ f->residue_config = (Residue *) setup_malloc(f, f->residue_count * sizeof(f->residue_config[0]));
+ if (f->residue_config == NULL) return error(f, VORBIS_outofmem);
+ memset(f->residue_config, 0, f->residue_count * sizeof(f->residue_config[0]));
+ for (i=0; i < f->residue_count; ++i) {
+ uint8 residue_cascade[64];
+ Residue *r = f->residue_config+i;
+ f->residue_types[i] = get_bits(f, 16);
+ if (f->residue_types[i] > 2) return error(f, VORBIS_invalid_setup);
+ r->begin = get_bits(f, 24);
+ r->end = get_bits(f, 24);
+ if (r->end < r->begin) return error(f, VORBIS_invalid_setup);
+ r->part_size = get_bits(f,24)+1;
+ r->classifications = get_bits(f,6)+1;
+ r->classbook = get_bits(f,8);
+ if (r->classbook >= f->codebook_count) return error(f, VORBIS_invalid_setup);
+ for (j=0; j < r->classifications; ++j) {
+ uint8 high_bits=0;
+ uint8 low_bits=get_bits(f,3);
+ if (get_bits(f,1))
+ high_bits = get_bits(f,5);
+ residue_cascade[j] = high_bits*8 + low_bits;
+ }
+ r->residue_books = (short (*)[8]) setup_malloc(f, sizeof(r->residue_books[0]) * r->classifications);
+ if (r->residue_books == NULL) return error(f, VORBIS_outofmem);
+ for (j=0; j < r->classifications; ++j) {
+ for (k=0; k < 8; ++k) {
+ if (residue_cascade[j] & (1 << k)) {
+ r->residue_books[j][k] = get_bits(f, 8);
+ if (r->residue_books[j][k] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
+ } else {
+ r->residue_books[j][k] = -1;
+ }
+ }
+ }
+ // precompute the classifications[] array to avoid inner-loop mod/divide
+ // call it 'classdata' since we already have r->classifications
+ r->classdata = (uint8 **) setup_malloc(f, sizeof(*r->classdata) * f->codebooks[r->classbook].entries);
+ if (!r->classdata) return error(f, VORBIS_outofmem);
+ memset(r->classdata, 0, sizeof(*r->classdata) * f->codebooks[r->classbook].entries);
+ for (j=0; j < f->codebooks[r->classbook].entries; ++j) {
+ int classwords = f->codebooks[r->classbook].dimensions;
+ int temp = j;
+ r->classdata[j] = (uint8 *) setup_malloc(f, sizeof(r->classdata[j][0]) * classwords);
+ if (r->classdata[j] == NULL) return error(f, VORBIS_outofmem);
+ for (k=classwords-1; k >= 0; --k) {
+ r->classdata[j][k] = temp % r->classifications;
+ temp /= r->classifications;
+ }
+ }
+ }
+
+ f->mapping_count = get_bits(f,6)+1;
+ f->mapping = (Mapping *) setup_malloc(f, f->mapping_count * sizeof(*f->mapping));
+ if (f->mapping == NULL) return error(f, VORBIS_outofmem);
+ memset(f->mapping, 0, f->mapping_count * sizeof(*f->mapping));
+ for (i=0; i < f->mapping_count; ++i) {
+ Mapping *m = f->mapping + i;
+ int mapping_type = get_bits(f,16);
+ if (mapping_type != 0) return error(f, VORBIS_invalid_setup);
+ m->chan = (MappingChannel *) setup_malloc(f, f->channels * sizeof(*m->chan));
+ if (m->chan == NULL) return error(f, VORBIS_outofmem);
+ if (get_bits(f,1))
+ m->submaps = get_bits(f,4)+1;
+ else
+ m->submaps = 1;
+ if (m->submaps > max_submaps)
+ max_submaps = m->submaps;
+ if (get_bits(f,1)) {
+ m->coupling_steps = get_bits(f,8)+1;
+ for (k=0; k < m->coupling_steps; ++k) {
+ m->chan[k].magnitude = get_bits(f, ilog(f->channels-1));
+ m->chan[k].angle = get_bits(f, ilog(f->channels-1));
+ if (m->chan[k].magnitude >= f->channels) return error(f, VORBIS_invalid_setup);
+ if (m->chan[k].angle >= f->channels) return error(f, VORBIS_invalid_setup);
+ if (m->chan[k].magnitude == m->chan[k].angle) return error(f, VORBIS_invalid_setup);
+ }
+ } else
+ m->coupling_steps = 0;
+
+ // reserved field
+ if (get_bits(f,2)) return error(f, VORBIS_invalid_setup);
+ if (m->submaps > 1) {
+ for (j=0; j < f->channels; ++j) {
+ m->chan[j].mux = get_bits(f, 4);
+ if (m->chan[j].mux >= m->submaps) return error(f, VORBIS_invalid_setup);
+ }
+ } else
+ // @SPECIFICATION: this case is missing from the spec
+ for (j=0; j < f->channels; ++j)
+ m->chan[j].mux = 0;
+
+ for (j=0; j < m->submaps; ++j) {
+ get_bits(f,8); // discard
+ m->submap_floor[j] = get_bits(f,8);
+ m->submap_residue[j] = get_bits(f,8);
+ if (m->submap_floor[j] >= f->floor_count) return error(f, VORBIS_invalid_setup);
+ if (m->submap_residue[j] >= f->residue_count) return error(f, VORBIS_invalid_setup);
+ }
+ }
+
+ // Modes
+ f->mode_count = get_bits(f, 6)+1;
+ for (i=0; i < f->mode_count; ++i) {
+ Mode *m = f->mode_config+i;
+ m->blockflag = get_bits(f,1);
+ m->windowtype = get_bits(f,16);
+ m->transformtype = get_bits(f,16);
+ m->mapping = get_bits(f,8);
+ if (m->windowtype != 0) return error(f, VORBIS_invalid_setup);
+ if (m->transformtype != 0) return error(f, VORBIS_invalid_setup);
+ if (m->mapping >= f->mapping_count) return error(f, VORBIS_invalid_setup);
+ }
+
+ flush_packet(f);
+
+ f->previous_length = 0;
+
+ for (i=0; i < f->channels; ++i) {
+ f->channel_buffers[i] = (float *) setup_malloc(f, sizeof(float) * f->blocksize_1);
+ f->previous_window[i] = (float *) setup_malloc(f, sizeof(float) * f->blocksize_1/2);
+ f->finalY[i] = (int16 *) setup_malloc(f, sizeof(int16) * longest_floorlist);
+ if (f->channel_buffers[i] == NULL || f->previous_window[i] == NULL || f->finalY[i] == NULL) return error(f, VORBIS_outofmem);
+ #ifdef STB_VORBIS_NO_DEFER_FLOOR
+ f->floor_buffers[i] = (float *) setup_malloc(f, sizeof(float) * f->blocksize_1/2);
+ if (f->floor_buffers[i] == NULL) return error(f, VORBIS_outofmem);
+ #endif
+ }
+
+ if (!init_blocksize(f, 0, f->blocksize_0)) return FALSE;
+ if (!init_blocksize(f, 1, f->blocksize_1)) return FALSE;
+ f->blocksize[0] = f->blocksize_0;
+ f->blocksize[1] = f->blocksize_1;
+
+#ifdef STB_VORBIS_DIVIDE_TABLE
+ if (integer_divide_table[1][1]==0)
+ for (i=0; i < DIVTAB_NUMER; ++i)
+ for (j=1; j < DIVTAB_DENOM; ++j)
+ integer_divide_table[i][j] = i / j;
+#endif
+
+ // compute how much temporary memory is needed
+
+ // 1.
+ {
+ uint32 imdct_mem = (f->blocksize_1 * sizeof(float) >> 1);
+ uint32 classify_mem;
+ int i,max_part_read=0;
+ for (i=0; i < f->residue_count; ++i) {
+ Residue *r = f->residue_config + i;
+ int n_read = r->end - r->begin;
+ int part_read = n_read / r->part_size;
+ if (part_read > max_part_read)
+ max_part_read = part_read;
+ }
+ #ifndef STB_VORBIS_DIVIDES_IN_RESIDUE
+ classify_mem = f->channels * (sizeof(void*) + max_part_read * sizeof(uint8 *));
+ #else
+ classify_mem = f->channels * (sizeof(void*) + max_part_read * sizeof(int *));
+ #endif
+
+ f->temp_memory_required = classify_mem;
+ if (imdct_mem > f->temp_memory_required)
+ f->temp_memory_required = imdct_mem;
+ }
+
+ f->first_decode = TRUE;
+
+ if (f->alloc.alloc_buffer) {
+ assert(f->temp_offset == f->alloc.alloc_buffer_length_in_bytes);
+ // check if there's enough temp memory so we don't error later
+ if (f->setup_offset + sizeof(*f) + f->temp_memory_required > (unsigned) f->temp_offset)
+ return error(f, VORBIS_outofmem);
+ }
+
+ f->first_audio_page_offset = stb_vorbis_get_file_offset(f);
+
+ return TRUE;
+}
+
+static void vorbis_deinit(stb_vorbis *p)
+{
+ int i,j;
+ if (p->residue_config) {
+ for (i=0; i < p->residue_count; ++i) {
+ Residue *r = p->residue_config+i;
+ if (r->classdata) {
+ for (j=0; j < p->codebooks[r->classbook].entries; ++j)
+ setup_free(p, r->classdata[j]);
+ setup_free(p, r->classdata);
+ }
+ setup_free(p, r->residue_books);
+ }
+ }
+
+ if (p->codebooks) {
+ CHECK(p);
+ for (i=0; i < p->codebook_count; ++i) {
+ Codebook *c = p->codebooks + i;
+ setup_free(p, c->codeword_lengths);
+ setup_free(p, c->multiplicands);
+ setup_free(p, c->codewords);
+ setup_free(p, c->sorted_codewords);
+ // c->sorted_values[-1] is the first entry in the array
+ setup_free(p, c->sorted_values ? c->sorted_values-1 : NULL);
+ }
+ setup_free(p, p->codebooks);
+ }
+ setup_free(p, p->floor_config);
+ setup_free(p, p->residue_config);
+ if (p->mapping) {
+ for (i=0; i < p->mapping_count; ++i)
+ setup_free(p, p->mapping[i].chan);
+ setup_free(p, p->mapping);
+ }
+ CHECK(p);
+ for (i=0; i < p->channels && i < STB_VORBIS_MAX_CHANNELS; ++i) {
+ setup_free(p, p->channel_buffers[i]);
+ setup_free(p, p->previous_window[i]);
+ #ifdef STB_VORBIS_NO_DEFER_FLOOR
+ setup_free(p, p->floor_buffers[i]);
+ #endif
+ setup_free(p, p->finalY[i]);
+ }
+ for (i=0; i < 2; ++i) {
+ setup_free(p, p->A[i]);
+ setup_free(p, p->B[i]);
+ setup_free(p, p->C[i]);
+ setup_free(p, p->window[i]);
+ setup_free(p, p->bit_reverse[i]);
+ }
+ #ifndef STB_VORBIS_NO_STDIO
+ if (p->close_on_free) fclose(p->f);
+ #endif
+}
+
+void stb_vorbis_close(stb_vorbis *p)
+{
+ if (p == NULL) return;
+ vorbis_deinit(p);
+ setup_free(p,p);
+}
+
+static void vorbis_init(stb_vorbis *p, const stb_vorbis_alloc *z)
+{
+ memset(p, 0, sizeof(*p)); // NULL out all malloc'd pointers to start
+ if (z) {
+ p->alloc = *z;
+ p->alloc.alloc_buffer_length_in_bytes = (p->alloc.alloc_buffer_length_in_bytes+3) & ~3;
+ p->temp_offset = p->alloc.alloc_buffer_length_in_bytes;
+ }
+ p->eof = 0;
+ p->error = VORBIS__no_error;
+ p->stream = NULL;
+ p->codebooks = NULL;
+ p->page_crc_tests = -1;
+ #ifndef STB_VORBIS_NO_STDIO
+ p->close_on_free = FALSE;
+ p->f = NULL;
+ #endif
+}
+
+int stb_vorbis_get_sample_offset(stb_vorbis *f)
+{
+ if (f->current_loc_valid)
+ return f->current_loc;
+ else
+ return -1;
+}
+
+stb_vorbis_info stb_vorbis_get_info(stb_vorbis *f)
+{
+ stb_vorbis_info d;
+ d.channels = f->channels;
+ d.sample_rate = f->sample_rate;
+ d.setup_memory_required = f->setup_memory_required;
+ d.setup_temp_memory_required = f->setup_temp_memory_required;
+ d.temp_memory_required = f->temp_memory_required;
+ d.max_frame_size = f->blocksize_1 >> 1;
+ return d;
+}
+
+int stb_vorbis_get_error(stb_vorbis *f)
+{
+ int e = f->error;
+ f->error = VORBIS__no_error;
+ return e;
+}
+
+static stb_vorbis * vorbis_alloc(stb_vorbis *f)
+{
+ stb_vorbis *p = (stb_vorbis *) setup_malloc(f, sizeof(*p));
+ return p;
+}
+
+#ifndef STB_VORBIS_NO_PUSHDATA_API
+
+void stb_vorbis_flush_pushdata(stb_vorbis *f)
+{
+ f->previous_length = 0;
+ f->page_crc_tests = 0;
+ f->discard_samples_deferred = 0;
+ f->current_loc_valid = FALSE;
+ f->first_decode = FALSE;
+ f->samples_output = 0;
+ f->channel_buffer_start = 0;
+ f->channel_buffer_end = 0;
+}
+
+static int vorbis_search_for_page_pushdata(vorb *f, uint8 *data, int data_len)
+{
+ int i,n;
+ for (i=0; i < f->page_crc_tests; ++i)
+ f->scan[i].bytes_done = 0;
+
+ // if we have room for more scans, search for them first, because
+ // they may cause us to stop early if their header is incomplete
+ if (f->page_crc_tests < STB_VORBIS_PUSHDATA_CRC_COUNT) {
+ if (data_len < 4) return 0;
+ data_len -= 3; // need to look for 4-byte sequence, so don't miss
+ // one that straddles a boundary
+ for (i=0; i < data_len; ++i) {
+ if (data[i] == 0x4f) {
+ if (0==memcmp(data+i, ogg_page_header, 4)) {
+ int j,len;
+ uint32 crc;
+ // make sure we have the whole page header
+ if (i+26 >= data_len || i+27+data[i+26] >= data_len) {
+ // only read up to this page start, so hopefully we'll
+ // have the whole page header start next time
+ data_len = i;
+ break;
+ }
+ // ok, we have it all; compute the length of the page
+ len = 27 + data[i+26];
+ for (j=0; j < data[i+26]; ++j)
+ len += data[i+27+j];
+ // scan everything up to the embedded crc (which we must 0)
+ crc = 0;
+ for (j=0; j < 22; ++j)
+ crc = crc32_update(crc, data[i+j]);
+ // now process 4 0-bytes
+ for ( ; j < 26; ++j)
+ crc = crc32_update(crc, 0);
+ // len is the total number of bytes we need to scan
+ n = f->page_crc_tests++;
+ f->scan[n].bytes_left = len-j;
+ f->scan[n].crc_so_far = crc;
+ f->scan[n].goal_crc = data[i+22] + (data[i+23] << 8) + (data[i+24]<<16) + (data[i+25]<<24);
+ // if the last frame on a page is continued to the next, then
+ // we can't recover the sample_loc immediately
+ if (data[i+27+data[i+26]-1] == 255)
+ f->scan[n].sample_loc = ~0;
+ else
+ f->scan[n].sample_loc = data[i+6] + (data[i+7] << 8) + (data[i+ 8]<<16) + (data[i+ 9]<<24);
+ f->scan[n].bytes_done = i+j;
+ if (f->page_crc_tests == STB_VORBIS_PUSHDATA_CRC_COUNT)
+ break;
+ // keep going if we still have room for more
+ }
+ }
+ }
+ }
+
+ for (i=0; i < f->page_crc_tests;) {
+ uint32 crc;
+ int j;
+ int n = f->scan[i].bytes_done;
+ int m = f->scan[i].bytes_left;
+ if (m > data_len - n) m = data_len - n;
+ // m is the bytes to scan in the current chunk
+ crc = f->scan[i].crc_so_far;
+ for (j=0; j < m; ++j)
+ crc = crc32_update(crc, data[n+j]);
+ f->scan[i].bytes_left -= m;
+ f->scan[i].crc_so_far = crc;
+ if (f->scan[i].bytes_left == 0) {
+ // does it match?
+ if (f->scan[i].crc_so_far == f->scan[i].goal_crc) {
+ // Houston, we have page
+ data_len = n+m; // consumption amount is wherever that scan ended
+ f->page_crc_tests = -1; // drop out of page scan mode
+ f->previous_length = 0; // decode-but-don't-output one frame
+ f->next_seg = -1; // start a new page
+ f->current_loc = f->scan[i].sample_loc; // set the current sample location
+ // to the amount we'd have decoded had we decoded this page
+ f->current_loc_valid = f->current_loc != ~0U;
+ return data_len;
+ }
+ // delete entry
+ f->scan[i] = f->scan[--f->page_crc_tests];
+ } else {
+ ++i;
+ }
+ }
+
+ return data_len;
+}
+
+// return value: number of bytes we used
+int stb_vorbis_decode_frame_pushdata(
+ stb_vorbis *f, // the file we're decoding
+ const uint8 *data, int data_len, // the memory available for decoding
+ int *channels, // place to write number of float * buffers
+ float ***output, // place to write float ** array of float * buffers
+ int *samples // place to write number of output samples
+ )
+{
+ int i;
+ int len,right,left;
+
+ if (!IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
+
+ if (f->page_crc_tests >= 0) {
+ *samples = 0;
+ return vorbis_search_for_page_pushdata(f, (uint8 *) data, data_len);
+ }
+
+ f->stream = (uint8 *) data;
+ f->stream_end = (uint8 *) data + data_len;
+ f->error = VORBIS__no_error;
+
+ // check that we have the entire packet in memory
+ if (!is_whole_packet_present(f, FALSE)) {
+ *samples = 0;
+ return 0;
+ }
+
+ if (!vorbis_decode_packet(f, &len, &left, &right)) {
+ // save the actual error we encountered
+ enum STBVorbisError error = f->error;
+ if (error == VORBIS_bad_packet_type) {
+ // flush and resynch
+ f->error = VORBIS__no_error;
+ while (get8_packet(f) != EOP)
+ if (f->eof) break;
+ *samples = 0;
+ return (int) (f->stream - data);
+ }
+ if (error == VORBIS_continued_packet_flag_invalid) {
+ if (f->previous_length == 0) {
+ // we may be resynching, in which case it's ok to hit one
+ // of these; just discard the packet
+ f->error = VORBIS__no_error;
+ while (get8_packet(f) != EOP)
+ if (f->eof) break;
+ *samples = 0;
+ return (int) (f->stream - data);
+ }
+ }
+ // if we get an error while parsing, what to do?
+ // well, it DEFINITELY won't work to continue from where we are!
+ stb_vorbis_flush_pushdata(f);
+ // restore the error that actually made us bail
+ f->error = error;
+ *samples = 0;
+ return 1;
+ }
+
+ // success!
+ len = vorbis_finish_frame(f, len, left, right);
+ for (i=0; i < f->channels; ++i)
+ f->outputs[i] = f->channel_buffers[i] + left;
+
+ if (channels) *channels = f->channels;
+ *samples = len;
+ *output = f->outputs;
+ return (int) (f->stream - data);
+}
+
+stb_vorbis *stb_vorbis_open_pushdata(
+ const unsigned char *data, int data_len, // the memory available for decoding
+ int *data_used, // only defined if result is not NULL
+ int *error, const stb_vorbis_alloc *alloc)
+{
+ stb_vorbis *f, p;
+ vorbis_init(&p, alloc);
+ p.stream = (uint8 *) data;
+ p.stream_end = (uint8 *) data + data_len;
+ p.push_mode = TRUE;
+ if (!start_decoder(&p)) {
+ if (p.eof)
+ *error = VORBIS_need_more_data;
+ else
+ *error = p.error;
+ return NULL;
+ }
+ f = vorbis_alloc(&p);
+ if (f) {
+ *f = p;
+ *data_used = (int) (f->stream - data);
+ *error = 0;
+ return f;
+ } else {
+ vorbis_deinit(&p);
+ return NULL;
+ }
+}
+#endif // STB_VORBIS_NO_PUSHDATA_API
+
+unsigned int stb_vorbis_get_file_offset(stb_vorbis *f)
+{
+ #ifndef STB_VORBIS_NO_PUSHDATA_API
+ if (f->push_mode) return 0;
+ #endif
+ if (USE_MEMORY(f)) return (unsigned int) (f->stream - f->stream_start);
+ #ifndef STB_VORBIS_NO_STDIO
+ return (unsigned int) (ftell(f->f) - f->f_start);
+ #endif
+}
+
+#ifndef STB_VORBIS_NO_PULLDATA_API
+//
+// DATA-PULLING API
+//
+
+static uint32 vorbis_find_page(stb_vorbis *f, uint32 *end, uint32 *last)
+{
+ for(;;) {
+ int n;
+ if (f->eof) return 0;
+ n = get8(f);
+ if (n == 0x4f) { // page header candidate
+ unsigned int retry_loc = stb_vorbis_get_file_offset(f);
+ int i;
+ // check if we're off the end of a file_section stream
+ if (retry_loc - 25 > f->stream_len)
+ return 0;
+ // check the rest of the header
+ for (i=1; i < 4; ++i)
+ if (get8(f) != ogg_page_header[i])
+ break;
+ if (f->eof) return 0;
+ if (i == 4) {
+ uint8 header[27];
+ uint32 i, crc, goal, len;
+ for (i=0; i < 4; ++i)
+ header[i] = ogg_page_header[i];
+ for (; i < 27; ++i)
+ header[i] = get8(f);
+ if (f->eof) return 0;
+ if (header[4] != 0) goto invalid;
+ goal = header[22] + (header[23] << 8) + (header[24]<<16) + (header[25]<<24);
+ for (i=22; i < 26; ++i)
+ header[i] = 0;
+ crc = 0;
+ for (i=0; i < 27; ++i)
+ crc = crc32_update(crc, header[i]);
+ len = 0;
+ for (i=0; i < header[26]; ++i) {
+ int s = get8(f);
+ crc = crc32_update(crc, s);
+ len += s;
+ }
+ if (len && f->eof) return 0;
+ for (i=0; i < len; ++i)
+ crc = crc32_update(crc, get8(f));
+ // finished parsing probable page
+ if (crc == goal) {
+ // we could now check that it's either got the last
+ // page flag set, OR it's followed by the capture
+ // pattern, but I guess TECHNICALLY you could have
+ // a file with garbage between each ogg page and recover
+ // from it automatically? So even though that paranoia
+ // might decrease the chance of an invalid decode by
+ // another 2^32, not worth it since it would hose those
+ // invalid-but-useful files?
+ if (end)
+ *end = stb_vorbis_get_file_offset(f);
+ if (last) {
+ if (header[5] & 0x04)
+ *last = 1;
+ else
+ *last = 0;
+ }
+ set_file_offset(f, retry_loc-1);
+ return 1;
+ }
+ }
+ invalid:
+ // not a valid page, so rewind and look for next one
+ set_file_offset(f, retry_loc);
+ }
+ }
+}
+
+
+#define SAMPLE_unknown 0xffffffff
+
+// seeking is implemented with a binary search, which narrows down the range to
+// 64K, before using a linear search (because finding the synchronization
+// pattern can be expensive, and the chance we'd find the end page again is
+// relatively high for small ranges)
+//
+// two initial interpolation-style probes are used at the start of the search
+// to try to bound either side of the binary search sensibly, while still
+// working in O(log n) time if they fail.
+
+static int get_seek_page_info(stb_vorbis *f, ProbedPage *z)
+{
+ uint8 header[27], lacing[255];
+ int i,len;
+
+ // record where the page starts
+ z->page_start = stb_vorbis_get_file_offset(f);
+
+ // parse the header
+ getn(f, header, 27);
+ if (header[0] != 'O' || header[1] != 'g' || header[2] != 'g' || header[3] != 'S')
+ return 0;
+ getn(f, lacing, header[26]);
+
+ // determine the length of the payload
+ len = 0;
+ for (i=0; i < header[26]; ++i)
+ len += lacing[i];
+
+ // this implies where the page ends
+ z->page_end = z->page_start + 27 + header[26] + len;
+
+ // read the last-decoded sample out of the data
+ z->last_decoded_sample = header[6] + (header[7] << 8) + (header[8] << 16) + (header[9] << 24);
+
+ // restore file state to where we were
+ set_file_offset(f, z->page_start);
+ return 1;
+}
+
+// rarely used function to seek back to the preceeding page while finding the
+// start of a packet
+static int go_to_page_before(stb_vorbis *f, unsigned int limit_offset)
+{
+ unsigned int previous_safe, end;
+
+ // now we want to seek back 64K from the limit
+ if (limit_offset >= 65536 && limit_offset-65536 >= f->first_audio_page_offset)
+ previous_safe = limit_offset - 65536;
+ else
+ previous_safe = f->first_audio_page_offset;
+
+ set_file_offset(f, previous_safe);
+
+ while (vorbis_find_page(f, &end, NULL)) {
+ if (end >= limit_offset && stb_vorbis_get_file_offset(f) < limit_offset)
+ return 1;
+ set_file_offset(f, end);
+ }
+
+ return 0;
+}
+
+// implements the search logic for finding a page and starting decoding. if
+// the function succeeds, current_loc_valid will be true and current_loc will
+// be less than or equal to the provided sample number (the closer the
+// better).
+static int seek_to_sample_coarse(stb_vorbis *f, uint32 sample_number)
+{
+ ProbedPage left, right, mid;
+ int i, start_seg_with_known_loc, end_pos, page_start;
+ uint32 delta, stream_length, padding;
+ double offset, bytes_per_sample;
+ int probe = 0;
+
+ // find the last page and validate the target sample
+ stream_length = stb_vorbis_stream_length_in_samples(f);
+ if (stream_length == 0) return error(f, VORBIS_seek_without_length);
+ if (sample_number > stream_length) return error(f, VORBIS_seek_invalid);
+
+ // this is the maximum difference between the window-center (which is the
+ // actual granule position value), and the right-start (which the spec
+ // indicates should be the granule position (give or take one)).
+ padding = ((f->blocksize_1 - f->blocksize_0) >> 2);
+ if (sample_number < padding)
+ sample_number = 0;
+ else
+ sample_number -= padding;
+
+ left = f->p_first;
+ while (left.last_decoded_sample == ~0U) {
+ // (untested) the first page does not have a 'last_decoded_sample'
+ set_file_offset(f, left.page_end);
+ if (!get_seek_page_info(f, &left)) goto error;
+ }
+
+ right = f->p_last;
+ assert(right.last_decoded_sample != ~0U);
+
+ // starting from the start is handled differently
+ if (sample_number <= left.last_decoded_sample) {
+ stb_vorbis_seek_start(f);
+ return 1;
+ }
+
+ while (left.page_end != right.page_start) {
+ assert(left.page_end < right.page_start);
+ // search range in bytes
+ delta = right.page_start - left.page_end;
+ if (delta <= 65536) {
+ // there's only 64K left to search - handle it linearly
+ set_file_offset(f, left.page_end);
+ } else {
+ if (probe < 2) {
+ if (probe == 0) {
+ // first probe (interpolate)
+ double data_bytes = right.page_end - left.page_start;
+ bytes_per_sample = data_bytes / right.last_decoded_sample;
+ offset = left.page_start + bytes_per_sample * (sample_number - left.last_decoded_sample);
+ } else {
+ // second probe (try to bound the other side)
+ double error = ((double) sample_number - mid.last_decoded_sample) * bytes_per_sample;
+ if (error >= 0 && error < 8000) error = 8000;
+ if (error < 0 && error > -8000) error = -8000;
+ offset += error * 2;
+ }
+
+ // ensure the offset is valid
+ if (offset < left.page_end)
+ offset = left.page_end;
+ if (offset > right.page_start - 65536)
+ offset = right.page_start - 65536;
+
+ set_file_offset(f, (unsigned int) offset);
+ } else {
+ // binary search for large ranges (offset by 32K to ensure
+ // we don't hit the right page)
+ set_file_offset(f, left.page_end + (delta / 2) - 32768);
+ }
+
+ if (!vorbis_find_page(f, NULL, NULL)) goto error;
+ }
+
+ for (;;) {
+ if (!get_seek_page_info(f, &mid)) goto error;
+ if (mid.last_decoded_sample != ~0U) break;
+ // (untested) no frames end on this page
+ set_file_offset(f, mid.page_end);
+ assert(mid.page_start < right.page_start);
+ }
+
+ // if we've just found the last page again then we're in a tricky file,
+ // and we're close enough.
+ if (mid.page_start == right.page_start)
+ break;
+
+ if (sample_number < mid.last_decoded_sample)
+ right = mid;
+ else
+ left = mid;
+
+ ++probe;
+ }
+
+ // seek back to start of the last packet
+ page_start = left.page_start;
+ set_file_offset(f, page_start);
+ if (!start_page(f)) return error(f, VORBIS_seek_failed);
+ end_pos = f->end_seg_with_known_loc;
+ assert(end_pos >= 0);
+
+ for (;;) {
+ for (i = end_pos; i > 0; --i)
+ if (f->segments[i-1] != 255)
+ break;
+
+ start_seg_with_known_loc = i;
+
+ if (start_seg_with_known_loc > 0 || !(f->page_flag & PAGEFLAG_continued_packet))
+ break;
+
+ // (untested) the final packet begins on an earlier page
+ if (!go_to_page_before(f, page_start))
+ goto error;
+
+ page_start = stb_vorbis_get_file_offset(f);
+ if (!start_page(f)) goto error;
+ end_pos = f->segment_count - 1;
+ }
+
+ // prepare to start decoding
+ f->current_loc_valid = FALSE;
+ f->last_seg = FALSE;
+ f->valid_bits = 0;
+ f->packet_bytes = 0;
+ f->bytes_in_seg = 0;
+ f->previous_length = 0;
+ f->next_seg = start_seg_with_known_loc;
+
+ for (i = 0; i < start_seg_with_known_loc; i++)
+ skip(f, f->segments[i]);
+
+ // start decoding (optimizable - this frame is generally discarded)
+ vorbis_pump_first_frame(f);
+ return 1;
+
+error:
+ // try to restore the file to a valid state
+ stb_vorbis_seek_start(f);
+ return error(f, VORBIS_seek_failed);
+}
+
+// the same as vorbis_decode_initial, but without advancing
+static int peek_decode_initial(vorb *f, int *p_left_start, int *p_left_end, int *p_right_start, int *p_right_end, int *mode)
+{
+ int bits_read, bytes_read;
+
+ if (!vorbis_decode_initial(f, p_left_start, p_left_end, p_right_start, p_right_end, mode))
+ return 0;
+
+ // either 1 or 2 bytes were read, figure out which so we can rewind
+ bits_read = 1 + ilog(f->mode_count-1);
+ if (f->mode_config[*mode].blockflag)
+ bits_read += 2;
+ bytes_read = (bits_read + 7) / 8;
+
+ f->bytes_in_seg += bytes_read;
+ f->packet_bytes -= bytes_read;
+ skip(f, -bytes_read);
+ if (f->next_seg == -1)
+ f->next_seg = f->segment_count - 1;
+ else
+ f->next_seg--;
+ f->valid_bits = 0;
+
+ return 1;
+}
+
+int stb_vorbis_seek_frame(stb_vorbis *f, unsigned int sample_number)
+{
+ uint32 max_frame_samples;
+
+ if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
+
+ // fast page-level search
+ if (!seek_to_sample_coarse(f, sample_number))
+ return 0;
+
+ assert(f->current_loc_valid);
+ assert(f->current_loc <= sample_number);
+
+ // linear search for the relevant packet
+ max_frame_samples = (f->blocksize_1*3 - f->blocksize_0) >> 2;
+ while (f->current_loc < sample_number) {
+ int left_start, left_end, right_start, right_end, mode, frame_samples;
+ if (!peek_decode_initial(f, &left_start, &left_end, &right_start, &right_end, &mode))
+ return error(f, VORBIS_seek_failed);
+ // calculate the number of samples returned by the next frame
+ frame_samples = right_start - left_start;
+ if (f->current_loc + frame_samples > sample_number) {
+ return 1; // the next frame will contain the sample
+ } else if (f->current_loc + frame_samples + max_frame_samples > sample_number) {
+ // there's a chance the frame after this could contain the sample
+ vorbis_pump_first_frame(f);
+ } else {
+ // this frame is too early to be relevant
+ f->current_loc += frame_samples;
+ f->previous_length = 0;
+ maybe_start_packet(f);
+ flush_packet(f);
+ }
+ }
+ // the next frame will start with the sample
+ assert(f->current_loc == sample_number);
+ return 1;
+}
+
+int stb_vorbis_seek(stb_vorbis *f, unsigned int sample_number)
+{
+ if (!stb_vorbis_seek_frame(f, sample_number))
+ return 0;
+
+ if (sample_number != f->current_loc) {
+ int n;
+ uint32 frame_start = f->current_loc;
+ stb_vorbis_get_frame_float(f, &n, NULL);
+ assert(sample_number > frame_start);
+ assert(f->channel_buffer_start + (int) (sample_number-frame_start) <= f->channel_buffer_end);
+ f->channel_buffer_start += (sample_number - frame_start);
+ }
+
+ return 1;
+}
+
+void stb_vorbis_seek_start(stb_vorbis *f)
+{
+ if (IS_PUSH_MODE(f)) { error(f, VORBIS_invalid_api_mixing); return; }
+ set_file_offset(f, f->first_audio_page_offset);
+ f->previous_length = 0;
+ f->first_decode = TRUE;
+ f->next_seg = -1;
+ vorbis_pump_first_frame(f);
+}
+
+unsigned int stb_vorbis_stream_length_in_samples(stb_vorbis *f)
+{
+ unsigned int restore_offset, previous_safe;
+ unsigned int end, last_page_loc;
+
+ if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
+ if (!f->total_samples) {
+ unsigned int last;
+ uint32 lo,hi;
+ char header[6];
+
+ // first, store the current decode position so we can restore it
+ restore_offset = stb_vorbis_get_file_offset(f);
+
+ // now we want to seek back 64K from the end (the last page must
+ // be at most a little less than 64K, but let's allow a little slop)
+ if (f->stream_len >= 65536 && f->stream_len-65536 >= f->first_audio_page_offset)
+ previous_safe = f->stream_len - 65536;
+ else
+ previous_safe = f->first_audio_page_offset;
+
+ set_file_offset(f, previous_safe);
+ // previous_safe is now our candidate 'earliest known place that seeking
+ // to will lead to the final page'
+
+ if (!vorbis_find_page(f, &end, &last)) {
+ // if we can't find a page, we're hosed!
+ f->error = VORBIS_cant_find_last_page;
+ f->total_samples = 0xffffffff;
+ goto done;
+ }
+
+ // check if there are more pages
+ last_page_loc = stb_vorbis_get_file_offset(f);
+
+ // stop when the last_page flag is set, not when we reach eof;
+ // this allows us to stop short of a 'file_section' end without
+ // explicitly checking the length of the section
+ while (!last) {
+ set_file_offset(f, end);
+ if (!vorbis_find_page(f, &end, &last)) {
+ // the last page we found didn't have the 'last page' flag
+ // set. whoops!
+ break;
+ }
+ previous_safe = last_page_loc+1;
+ last_page_loc = stb_vorbis_get_file_offset(f);
+ }
+
+ set_file_offset(f, last_page_loc);
+
+ // parse the header
+ getn(f, (unsigned char *)header, 6);
+ // extract the absolute granule position
+ lo = get32(f);
+ hi = get32(f);
+ if (lo == 0xffffffff && hi == 0xffffffff) {
+ f->error = VORBIS_cant_find_last_page;
+ f->total_samples = SAMPLE_unknown;
+ goto done;
+ }
+ if (hi)
+ lo = 0xfffffffe; // saturate
+ f->total_samples = lo;
+
+ f->p_last.page_start = last_page_loc;
+ f->p_last.page_end = end;
+ f->p_last.last_decoded_sample = lo;
+
+ done:
+ set_file_offset(f, restore_offset);
+ }
+ return f->total_samples == SAMPLE_unknown ? 0 : f->total_samples;
+}
+
+float stb_vorbis_stream_length_in_seconds(stb_vorbis *f)
+{
+ return stb_vorbis_stream_length_in_samples(f) / (float) f->sample_rate;
+}
+
+
+
+int stb_vorbis_get_frame_float(stb_vorbis *f, int *channels, float ***output)
+{
+ int len, right,left,i;
+ if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
+
+ if (!vorbis_decode_packet(f, &len, &left, &right)) {
+ f->channel_buffer_start = f->channel_buffer_end = 0;
+ return 0;
+ }
+
+ len = vorbis_finish_frame(f, len, left, right);
+ for (i=0; i < f->channels; ++i)
+ f->outputs[i] = f->channel_buffers[i] + left;
+
+ f->channel_buffer_start = left;
+ f->channel_buffer_end = left+len;
+
+ if (channels) *channels = f->channels;
+ if (output) *output = f->outputs;
+ return len;
+}
+
+#ifndef STB_VORBIS_NO_STDIO
+
+stb_vorbis * stb_vorbis_open_file_section(FILE *file, int close_on_free, int *error, const stb_vorbis_alloc *alloc, unsigned int length)
+{
+ stb_vorbis *f, p;
+ vorbis_init(&p, alloc);
+ p.f = file;
+ p.f_start = (uint32) ftell(file);
+ p.stream_len = length;
+ p.close_on_free = close_on_free;
+ if (start_decoder(&p)) {
+ f = vorbis_alloc(&p);
+ if (f) {
+ *f = p;
+ vorbis_pump_first_frame(f);
+ return f;
+ }
+ }
+ if (error) *error = p.error;
+ vorbis_deinit(&p);
+ return NULL;
+}
+
+stb_vorbis * stb_vorbis_open_file(FILE *file, int close_on_free, int *error, const stb_vorbis_alloc *alloc)
+{
+ unsigned int len, start;
+ start = (unsigned int) ftell(file);
+ fseek(file, 0, SEEK_END);
+ len = (unsigned int) (ftell(file) - start);
+ fseek(file, start, SEEK_SET);
+ return stb_vorbis_open_file_section(file, close_on_free, error, alloc, len);
+}
+
+stb_vorbis * stb_vorbis_open_filename(const char *filename, int *error, const stb_vorbis_alloc *alloc)
+{
+ FILE *f = fopen(filename, "rb");
+ if (f)
+ return stb_vorbis_open_file(f, TRUE, error, alloc);
+ if (error) *error = VORBIS_file_open_failure;
+ return NULL;
+}
+#endif // STB_VORBIS_NO_STDIO
+
+stb_vorbis * stb_vorbis_open_memory(const unsigned char *data, int len, int *error, const stb_vorbis_alloc *alloc)
+{
+ stb_vorbis *f, p;
+ if (data == NULL) return NULL;
+ vorbis_init(&p, alloc);
+ p.stream = (uint8 *) data;
+ p.stream_end = (uint8 *) data + len;
+ p.stream_start = (uint8 *) p.stream;
+ p.stream_len = len;
+ p.push_mode = FALSE;
+ if (start_decoder(&p)) {
+ f = vorbis_alloc(&p);
+ if (f) {
+ *f = p;
+ vorbis_pump_first_frame(f);
+ return f;
+ }
+ }
+ if (error) *error = p.error;
+ vorbis_deinit(&p);
+ return NULL;
+}
+
+#ifndef STB_VORBIS_NO_INTEGER_CONVERSION
+#define PLAYBACK_MONO 1
+#define PLAYBACK_LEFT 2
+#define PLAYBACK_RIGHT 4
+
+#define L (PLAYBACK_LEFT | PLAYBACK_MONO)
+#define C (PLAYBACK_LEFT | PLAYBACK_RIGHT | PLAYBACK_MONO)
+#define R (PLAYBACK_RIGHT | PLAYBACK_MONO)
+
+static int8 channel_position[7][6] =
+{
+ { 0 },
+ { C },
+ { L, R },
+ { L, C, R },
+ { L, R, L, R },
+ { L, C, R, L, R },
+ { L, C, R, L, R, C },
+};
+
+
+#ifndef STB_VORBIS_NO_FAST_SCALED_FLOAT
+ typedef union {
+ float f;
+ int i;
+ } float_conv;
+ typedef char stb_vorbis_float_size_test[sizeof(float)==4 && sizeof(int) == 4];
+ #define FASTDEF(x) float_conv x
+ // add (1<<23) to convert to int, then divide by 2^SHIFT, then add 0.5/2^SHIFT to round
+ #define MAGIC(SHIFT) (1.5f * (1 << (23-SHIFT)) + 0.5f/(1 << SHIFT))
+ #define ADDEND(SHIFT) (((150-SHIFT) << 23) + (1 << 22))
+ #define FAST_SCALED_FLOAT_TO_INT(temp,x,s) (temp.f = (x) + MAGIC(s), temp.i - ADDEND(s))
+ #define check_endianness()
+#else
+ #define FAST_SCALED_FLOAT_TO_INT(temp,x,s) ((int) ((x) * (1 << (s))))
+ #define check_endianness()
+ #define FASTDEF(x)
+#endif
+
+static void copy_samples(short *dest, float *src, int len)
+{
+ int i;
+ check_endianness();
+ for (i=0; i < len; ++i) {
+ FASTDEF(temp);
+ int v = FAST_SCALED_FLOAT_TO_INT(temp, src[i],15);
+ if ((unsigned int) (v + 32768) > 65535)
+ v = v < 0 ? -32768 : 32767;
+ dest[i] = v;
+ }
+}
+
+static void compute_samples(int mask, short *output, int num_c, float **data, int d_offset, int len)
+{
+ #define BUFFER_SIZE 32
+ float buffer[BUFFER_SIZE];
+ int i,j,o,n = BUFFER_SIZE;
+ check_endianness();
+ for (o = 0; o < len; o += BUFFER_SIZE) {
+ memset(buffer, 0, sizeof(buffer));
+ if (o + n > len) n = len - o;
+ for (j=0; j < num_c; ++j) {
+ if (channel_position[num_c][j] & mask) {
+ for (i=0; i < n; ++i)
+ buffer[i] += data[j][d_offset+o+i];
+ }
+ }
+ for (i=0; i < n; ++i) {
+ FASTDEF(temp);
+ int v = FAST_SCALED_FLOAT_TO_INT(temp,buffer[i],15);
+ if ((unsigned int) (v + 32768) > 65535)
+ v = v < 0 ? -32768 : 32767;
+ output[o+i] = v;
+ }
+ }
+}
+
+static void compute_stereo_samples(short *output, int num_c, float **data, int d_offset, int len)
+{
+ #define BUFFER_SIZE 32
+ float buffer[BUFFER_SIZE];
+ int i,j,o,n = BUFFER_SIZE >> 1;
+ // o is the offset in the source data
+ check_endianness();
+ for (o = 0; o < len; o += BUFFER_SIZE >> 1) {
+ // o2 is the offset in the output data
+ int o2 = o << 1;
+ memset(buffer, 0, sizeof(buffer));
+ if (o + n > len) n = len - o;
+ for (j=0; j < num_c; ++j) {
+ int m = channel_position[num_c][j] & (PLAYBACK_LEFT | PLAYBACK_RIGHT);
+ if (m == (PLAYBACK_LEFT | PLAYBACK_RIGHT)) {
+ for (i=0; i < n; ++i) {
+ buffer[i*2+0] += data[j][d_offset+o+i];
+ buffer[i*2+1] += data[j][d_offset+o+i];
+ }
+ } else if (m == PLAYBACK_LEFT) {
+ for (i=0; i < n; ++i) {
+ buffer[i*2+0] += data[j][d_offset+o+i];
+ }
+ } else if (m == PLAYBACK_RIGHT) {
+ for (i=0; i < n; ++i) {
+ buffer[i*2+1] += data[j][d_offset+o+i];
+ }
+ }
+ }
+ for (i=0; i < (n<<1); ++i) {
+ FASTDEF(temp);
+ int v = FAST_SCALED_FLOAT_TO_INT(temp,buffer[i],15);
+ if ((unsigned int) (v + 32768) > 65535)
+ v = v < 0 ? -32768 : 32767;
+ output[o2+i] = v;
+ }
+ }
+}
+
+static void convert_samples_short(int buf_c, short **buffer, int b_offset, int data_c, float **data, int d_offset, int samples)
+{
+ int i;
+ if (buf_c != data_c && buf_c <= 2 && data_c <= 6) {
+ static int channel_selector[3][2] = { {0}, {PLAYBACK_MONO}, {PLAYBACK_LEFT, PLAYBACK_RIGHT} };
+ for (i=0; i < buf_c; ++i)
+ compute_samples(channel_selector[buf_c][i], buffer[i]+b_offset, data_c, data, d_offset, samples);
+ } else {
+ int limit = buf_c < data_c ? buf_c : data_c;
+ for (i=0; i < limit; ++i)
+ copy_samples(buffer[i]+b_offset, data[i]+d_offset, samples);
+ for ( ; i < buf_c; ++i)
+ memset(buffer[i]+b_offset, 0, sizeof(short) * samples);
+ }
+}
+
+int stb_vorbis_get_frame_short(stb_vorbis *f, int num_c, short **buffer, int num_samples)
+{
+ float **output;
+ int len = stb_vorbis_get_frame_float(f, NULL, &output);
+ if (len > num_samples) len = num_samples;
+ if (len)
+ convert_samples_short(num_c, buffer, 0, f->channels, output, 0, len);
+ return len;
+}
+
+static void convert_channels_short_interleaved(int buf_c, short *buffer, int data_c, float **data, int d_offset, int len)
+{
+ int i;
+ check_endianness();
+ if (buf_c != data_c && buf_c <= 2 && data_c <= 6) {
+ assert(buf_c == 2);
+ for (i=0; i < buf_c; ++i)
+ compute_stereo_samples(buffer, data_c, data, d_offset, len);
+ } else {
+ int limit = buf_c < data_c ? buf_c : data_c;
+ int j;
+ for (j=0; j < len; ++j) {
+ for (i=0; i < limit; ++i) {
+ FASTDEF(temp);
+ float f = data[i][d_offset+j];
+ int v = FAST_SCALED_FLOAT_TO_INT(temp, f,15);//data[i][d_offset+j],15);
+ if ((unsigned int) (v + 32768) > 65535)
+ v = v < 0 ? -32768 : 32767;
+ *buffer++ = v;
+ }
+ for ( ; i < buf_c; ++i)
+ *buffer++ = 0;
+ }
+ }
+}
+
+int stb_vorbis_get_frame_short_interleaved(stb_vorbis *f, int num_c, short *buffer, int num_shorts)
+{
+ float **output;
+ int len;
+ if (num_c == 1) return stb_vorbis_get_frame_short(f,num_c,&buffer, num_shorts);
+ len = stb_vorbis_get_frame_float(f, NULL, &output);
+ if (len) {
+ if (len*num_c > num_shorts) len = num_shorts / num_c;
+ convert_channels_short_interleaved(num_c, buffer, f->channels, output, 0, len);
+ }
+ return len;
+}
+
+int stb_vorbis_get_samples_short_interleaved(stb_vorbis *f, int channels, short *buffer, int num_shorts)
+{
+ float **outputs;
+ int len = num_shorts / channels;
+ int n=0;
+ int z = f->channels;
+ if (z > channels) z = channels;
+ while (n < len) {
+ int k = f->channel_buffer_end - f->channel_buffer_start;
+ if (n+k >= len) k = len - n;
+ if (k)
+ convert_channels_short_interleaved(channels, buffer, f->channels, f->channel_buffers, f->channel_buffer_start, k);
+ buffer += k*channels;
+ n += k;
+ f->channel_buffer_start += k;
+ if (n == len) break;
+ if (!stb_vorbis_get_frame_float(f, NULL, &outputs)) break;
+ }
+ return n;
+}
+
+int stb_vorbis_get_samples_short(stb_vorbis *f, int channels, short **buffer, int len)
+{
+ float **outputs;
+ int n=0;
+ int z = f->channels;
+ if (z > channels) z = channels;
+ while (n < len) {
+ int k = f->channel_buffer_end - f->channel_buffer_start;
+ if (n+k >= len) k = len - n;
+ if (k)
+ convert_samples_short(channels, buffer, n, f->channels, f->channel_buffers, f->channel_buffer_start, k);
+ n += k;
+ f->channel_buffer_start += k;
+ if (n == len) break;
+ if (!stb_vorbis_get_frame_float(f, NULL, &outputs)) break;
+ }
+ return n;
+}
+
+#ifndef STB_VORBIS_NO_STDIO
+int stb_vorbis_decode_filename(const char *filename, int *channels, int *sample_rate, short **output)
+{
+ int data_len, offset, total, limit, error;
+ short *data;
+ stb_vorbis *v = stb_vorbis_open_filename(filename, &error, NULL);
+ if (v == NULL) return -1;
+ limit = v->channels * 4096;
+ *channels = v->channels;
+ if (sample_rate)
+ *sample_rate = v->sample_rate;
+ offset = data_len = 0;
+ total = limit;
+ data = (short *) malloc(total * sizeof(*data));
+ if (data == NULL) {
+ stb_vorbis_close(v);
+ return -2;
+ }
+ for (;;) {
+ int n = stb_vorbis_get_frame_short_interleaved(v, v->channels, data+offset, total-offset);
+ if (n == 0) break;
+ data_len += n;
+ offset += n * v->channels;
+ if (offset + limit > total) {
+ short *data2;
+ total *= 2;
+ data2 = (short *) realloc(data, total * sizeof(*data));
+ if (data2 == NULL) {
+ free(data);
+ stb_vorbis_close(v);
+ return -2;
+ }
+ data = data2;
+ }
+ }
+ *output = data;
+ stb_vorbis_close(v);
+ return data_len;
+}
+#endif // NO_STDIO
+
+int stb_vorbis_decode_memory(const uint8 *mem, int len, int *channels, int *sample_rate, short **output)
+{
+ int data_len, offset, total, limit, error;
+ short *data;
+ stb_vorbis *v = stb_vorbis_open_memory(mem, len, &error, NULL);
+ if (v == NULL) return -1;
+ limit = v->channels * 4096;
+ *channels = v->channels;
+ if (sample_rate)
+ *sample_rate = v->sample_rate;
+ offset = data_len = 0;
+ total = limit;
+ data = (short *) malloc(total * sizeof(*data));
+ if (data == NULL) {
+ stb_vorbis_close(v);
+ return -2;
+ }
+ for (;;) {
+ int n = stb_vorbis_get_frame_short_interleaved(v, v->channels, data+offset, total-offset);
+ if (n == 0) break;
+ data_len += n;
+ offset += n * v->channels;
+ if (offset + limit > total) {
+ short *data2;
+ total *= 2;
+ data2 = (short *) realloc(data, total * sizeof(*data));
+ if (data2 == NULL) {
+ free(data);
+ stb_vorbis_close(v);
+ return -2;
+ }
+ data = data2;
+ }
+ }
+ *output = data;
+ stb_vorbis_close(v);
+ return data_len;
+}
+#endif // STB_VORBIS_NO_INTEGER_CONVERSION
+
+int stb_vorbis_get_samples_float_interleaved(stb_vorbis *f, int channels, float *buffer, int num_floats)
+{
+ float **outputs;
+ int len = num_floats / channels;
+ int n=0;
+ int z = f->channels;
+ if (z > channels) z = channels;
+ while (n < len) {
+ int i,j;
+ int k = f->channel_buffer_end - f->channel_buffer_start;
+ if (n+k >= len) k = len - n;
+ for (j=0; j < k; ++j) {
+ for (i=0; i < z; ++i)
+ *buffer++ = f->channel_buffers[i][f->channel_buffer_start+j];
+ for ( ; i < channels; ++i)
+ *buffer++ = 0;
+ }
+ n += k;
+ f->channel_buffer_start += k;
+ if (n == len)
+ break;
+ if (!stb_vorbis_get_frame_float(f, NULL, &outputs))
+ break;
+ }
+ return n;
+}
+
+int stb_vorbis_get_samples_float(stb_vorbis *f, int channels, float **buffer, int num_samples)
+{
+ float **outputs;
+ int n=0;
+ int z = f->channels;
+ if (z > channels) z = channels;
+ while (n < num_samples) {
+ int i;
+ int k = f->channel_buffer_end - f->channel_buffer_start;
+ if (n+k >= num_samples) k = num_samples - n;
+ if (k) {
+ for (i=0; i < z; ++i)
+ memcpy(buffer[i]+n, f->channel_buffers[i]+f->channel_buffer_start, sizeof(float)*k);
+ for ( ; i < channels; ++i)
+ memset(buffer[i]+n, 0, sizeof(float) * k);
+ }
+ n += k;
+ f->channel_buffer_start += k;
+ if (n == num_samples)
+ break;
+ if (!stb_vorbis_get_frame_float(f, NULL, &outputs))
+ break;
+ }
+ return n;
+}
+#endif // STB_VORBIS_NO_PULLDATA_API
+
+/* Version history
+ 1.09 - 2016/04/04 - back out 'avoid discarding last frame' fix from previous version
+ 1.08 - 2016/04/02 - fixed multiple warnings; fix setup memory leaks;
+ avoid discarding last frame of audio data
+ 1.07 - 2015/01/16 - fixed some warnings, fix mingw, const-correct API
+ some more crash fixes when out of memory or with corrupt files
+ 1.06 - 2015/08/31 - full, correct support for seeking API (Dougall Johnson)
+ some crash fixes when out of memory or with corrupt files
+ 1.05 - 2015/04/19 - don't define __forceinline if it's redundant
+ 1.04 - 2014/08/27 - fix missing const-correct case in API
+ 1.03 - 2014/08/07 - Warning fixes
+ 1.02 - 2014/07/09 - Declare qsort compare function _cdecl on windows
+ 1.01 - 2014/06/18 - fix stb_vorbis_get_samples_float
+ 1.0 - 2014/05/26 - fix memory leaks; fix warnings; fix bugs in multichannel
+ (API change) report sample rate for decode-full-file funcs
+ 0.99996 - bracket #include <malloc.h> for macintosh compilation by Laurent Gomila
+ 0.99995 - use union instead of pointer-cast for fast-float-to-int to avoid alias-optimization problem
+ 0.99994 - change fast-float-to-int to work in single-precision FPU mode, remove endian-dependence
+ 0.99993 - remove assert that fired on legal files with empty tables
+ 0.99992 - rewind-to-start
+ 0.99991 - bugfix to stb_vorbis_get_samples_short by Bernhard Wodo
+ 0.9999 - (should have been 0.99990) fix no-CRT support, compiling as C++
+ 0.9998 - add a full-decode function with a memory source
+ 0.9997 - fix a bug in the read-from-FILE case in 0.9996 addition
+ 0.9996 - query length of vorbis stream in samples/seconds
+ 0.9995 - bugfix to another optimization that only happened in certain files
+ 0.9994 - bugfix to one of the optimizations that caused significant (but inaudible?) errors
+ 0.9993 - performance improvements; runs in 99% to 104% of time of reference implementation
+ 0.9992 - performance improvement of IMDCT; now performs close to reference implementation
+ 0.9991 - performance improvement of IMDCT
+ 0.999 - (should have been 0.9990) performance improvement of IMDCT
+ 0.998 - no-CRT support from Casey Muratori
+ 0.997 - bugfixes for bugs found by Terje Mathisen
+ 0.996 - bugfix: fast-huffman decode initialized incorrectly for sparse codebooks; fixing gives 10% speedup - found by Terje Mathisen
+ 0.995 - bugfix: fix to 'effective' overrun detection - found by Terje Mathisen
+ 0.994 - bugfix: garbage decode on final VQ symbol of a non-multiple - found by Terje Mathisen
+ 0.993 - bugfix: pushdata API required 1 extra byte for empty page (failed to consume final page if empty) - found by Terje Mathisen
+ 0.992 - fixes for MinGW warning
+ 0.991 - turn fast-float-conversion on by default
+ 0.990 - fix push-mode seek recovery if you seek into the headers
+ 0.98b - fix to bad release of 0.98
+ 0.98 - fix push-mode seek recovery; robustify float-to-int and support non-fast mode
+ 0.97 - builds under c++ (typecasting, don't use 'class' keyword)
+ 0.96 - somehow MY 0.95 was right, but the web one was wrong, so here's my 0.95 rereleased as 0.96, fixes a typo in the clamping code
+ 0.95 - clamping code for 16-bit functions
+ 0.94 - not publically released
+ 0.93 - fixed all-zero-floor case (was decoding garbage)
+ 0.92 - fixed a memory leak
+ 0.91 - conditional compiles to omit parts of the API and the infrastructure to support them: STB_VORBIS_NO_PULLDATA_API, STB_VORBIS_NO_PUSHDATA_API, STB_VORBIS_NO_STDIO, STB_VORBIS_NO_INTEGER_CONVERSION
+ 0.90 - first public release
+*/
+
+#endif // STB_VORBIS_HEADER_ONLY
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