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Diffstat (limited to 'drivers/webpold/utils/bit_reader.h')
-rw-r--r--drivers/webpold/utils/bit_reader.h198
1 files changed, 0 insertions, 198 deletions
diff --git a/drivers/webpold/utils/bit_reader.h b/drivers/webpold/utils/bit_reader.h
deleted file mode 100644
index 43cd948fd4..0000000000
--- a/drivers/webpold/utils/bit_reader.h
+++ /dev/null
@@ -1,198 +0,0 @@
-//
-// Copyright 2010 Google Inc. All Rights Reserved.
-//
-// This code is licensed under the same terms as WebM:
-// Software License Agreement: http://www.webmproject.org/license/software/
-// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
-// -----------------------------------------------------------------------------
-//
-// Boolean decoder
-//
-// Author: Skal (pascal.massimino@gmail.com)
-// Vikas Arora (vikaas.arora@gmail.com)
-
-#ifndef WEBP_UTILS_BIT_READER_H_
-#define WEBP_UTILS_BIT_READER_H_
-
-#include <assert.h>
-#ifdef _MSC_VER
-#include <stdlib.h> // _byteswap_ulong
-#endif
-#include <string.h> // For memcpy
-#include "../types.h"
-
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
-#define BITS 32 // can be 32, 16 or 8
-#define MASK ((((bit_t)1) << (BITS)) - 1)
-#if (BITS == 32)
-typedef uint64_t bit_t; // natural register type
-typedef uint32_t lbit_t; // natural type for memory I/O
-#elif (BITS == 16)
-typedef uint32_t bit_t;
-typedef uint16_t lbit_t;
-#else
-typedef uint32_t bit_t;
-typedef uint8_t lbit_t;
-#endif
-
-//------------------------------------------------------------------------------
-// Bitreader and code-tree reader
-
-typedef struct VP8BitReader VP8BitReader;
-struct VP8BitReader {
- const uint8_t* buf_; // next byte to be read
- const uint8_t* buf_end_; // end of read buffer
- int eof_; // true if input is exhausted
-
- // boolean decoder
- bit_t range_; // current range minus 1. In [127, 254] interval.
- bit_t value_; // current value
- int missing_; // number of missing bits in value_ (8bit)
-};
-
-// Initialize the bit reader and the boolean decoder.
-void VP8InitBitReader(VP8BitReader* const br,
- const uint8_t* const start, const uint8_t* const end);
-
-// return the next value made of 'num_bits' bits
-uint32_t VP8GetValue(VP8BitReader* const br, int num_bits);
-static WEBP_INLINE uint32_t VP8Get(VP8BitReader* const br) {
- return VP8GetValue(br, 1);
-}
-
-// return the next value with sign-extension.
-int32_t VP8GetSignedValue(VP8BitReader* const br, int num_bits);
-
-// Read a bit with proba 'prob'. Speed-critical function!
-extern const uint8_t kVP8Log2Range[128];
-extern const bit_t kVP8NewRange[128];
-
-void VP8LoadFinalBytes(VP8BitReader* const br); // special case for the tail
-
-static WEBP_INLINE void VP8LoadNewBytes(VP8BitReader* const br) {
- assert(br && br->buf_);
- // Read 'BITS' bits at a time if possible.
- if (br->buf_ + sizeof(lbit_t) <= br->buf_end_) {
- // convert memory type to register type (with some zero'ing!)
- bit_t bits;
- lbit_t in_bits = *(lbit_t*)br->buf_;
- br->buf_ += (BITS) >> 3;
-#if !defined(__BIG_ENDIAN__)
-#if (BITS == 32)
-#if defined(__i386__) || defined(__x86_64__)
- __asm__ volatile("bswap %k0" : "=r"(in_bits) : "0"(in_bits));
- bits = (bit_t)in_bits; // 32b -> 64b zero-extension
-#elif defined(_MSC_VER)
- bits = _byteswap_ulong(in_bits);
-#else
- bits = (bit_t)(in_bits >> 24) | ((in_bits >> 8) & 0xff00)
- | ((in_bits << 8) & 0xff0000) | (in_bits << 24);
-#endif // x86
-#elif (BITS == 16)
- // gcc will recognize a 'rorw $8, ...' here:
- bits = (bit_t)(in_bits >> 8) | ((in_bits & 0xff) << 8);
-#endif
-#else // LITTLE_ENDIAN
- bits = (bit_t)in_bits;
-#endif
- br->value_ |= bits << br->missing_;
- br->missing_ -= (BITS);
- } else {
- VP8LoadFinalBytes(br); // no need to be inlined
- }
-}
-
-static WEBP_INLINE int VP8BitUpdate(VP8BitReader* const br, bit_t split) {
- const bit_t value_split = split | (MASK);
- if (br->missing_ > 0) { // Make sure we have a least BITS bits in 'value_'
- VP8LoadNewBytes(br);
- }
- if (br->value_ > value_split) {
- br->range_ -= value_split + 1;
- br->value_ -= value_split + 1;
- return 1;
- } else {
- br->range_ = value_split;
- return 0;
- }
-}
-
-static WEBP_INLINE void VP8Shift(VP8BitReader* const br) {
- // range_ is in [0..127] interval here.
- const int idx = br->range_ >> (BITS);
- const int shift = kVP8Log2Range[idx];
- br->range_ = kVP8NewRange[idx];
- br->value_ <<= shift;
- br->missing_ += shift;
-}
-
-static WEBP_INLINE int VP8GetBit(VP8BitReader* const br, int prob) {
- // It's important to avoid generating a 64bit x 64bit multiply here.
- // We just need an 8b x 8b after all.
- const bit_t split =
- (bit_t)((uint32_t)(br->range_ >> (BITS)) * prob) << ((BITS) - 8);
- const int bit = VP8BitUpdate(br, split);
- if (br->range_ <= (((bit_t)0x7e << (BITS)) | (MASK))) {
- VP8Shift(br);
- }
- return bit;
-}
-
-static WEBP_INLINE int VP8GetSigned(VP8BitReader* const br, int v) {
- const bit_t split = (br->range_ >> 1);
- const int bit = VP8BitUpdate(br, split);
- VP8Shift(br);
- return bit ? -v : v;
-}
-
-
-// -----------------------------------------------------------------------------
-// Bitreader
-
-typedef struct {
- uint64_t val_;
- const uint8_t* buf_;
- size_t len_;
- size_t pos_;
- int bit_pos_;
- int eos_;
- int error_;
-} VP8LBitReader;
-
-void VP8LInitBitReader(VP8LBitReader* const br,
- const uint8_t* const start,
- size_t length);
-
-// Sets a new data buffer.
-void VP8LBitReaderSetBuffer(VP8LBitReader* const br,
- const uint8_t* const buffer, size_t length);
-
-// Reads the specified number of bits from Read Buffer.
-// Flags an error in case end_of_stream or n_bits is more than allowed limit.
-// Flags eos if this read attempt is going to cross the read buffer.
-uint32_t VP8LReadBits(VP8LBitReader* const br, int n_bits);
-
-// Reads one bit from Read Buffer. Flags an error in case end_of_stream.
-// Flags eos after reading last bit from the buffer.
-uint32_t VP8LReadOneBit(VP8LBitReader* const br);
-
-// VP8LReadOneBitUnsafe is faster than VP8LReadOneBit, but it can be called only
-// 32 times after the last VP8LFillBitWindow. Any subsequent calls
-// (without VP8LFillBitWindow) will return invalid data.
-static WEBP_INLINE uint32_t VP8LReadOneBitUnsafe(VP8LBitReader* const br) {
- const uint32_t val = (br->val_ >> br->bit_pos_) & 1;
- ++br->bit_pos_;
- return val;
-}
-
-// Advances the Read buffer by 4 bytes to make room for reading next 32 bits.
-void VP8LFillBitWindow(VP8LBitReader* const br);
-
-#if defined(__cplusplus) || defined(c_plusplus)
-} // extern "C"
-#endif
-
-#endif /* WEBP_UTILS_BIT_READER_H_ */
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