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diff --git a/thirdparty/libtheora/theora/theora.h b/thirdparty/libtheora/theora/theora.h new file mode 100644 index 0000000000..af6eb6f380 --- /dev/null +++ b/thirdparty/libtheora/theora/theora.h @@ -0,0 +1,784 @@ +/******************************************************************** + * * + * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. * + * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * + * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * + * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * + * * + * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 * + * by the Xiph.Org Foundation http://www.xiph.org/ * + * * + ******************************************************************** + + function: + last mod: $Id: theora.h,v 1.17 2003/12/06 18:06:19 arc Exp $ + + ********************************************************************/ + +#ifndef _O_THEORA_H_ +#define _O_THEORA_H_ + +#ifdef __cplusplus +extern "C" +{ +#endif /* __cplusplus */ + +#include <stddef.h> /* for size_t */ + +#include <ogg/ogg.h> + +/** \file + * The libtheora pre-1.0 legacy C API. + * + * \ingroup oldfuncs + * + * \section intro Introduction + * + * This is the documentation for the libtheora legacy C API, declared in + * the theora.h header, which describes the old interface used before + * the 1.0 release. This API was widely deployed for several years and + * remains supported, but for new code we recommend the cleaner API + * declared in theoradec.h and theoraenc.h. + * + * libtheora is the reference implementation for + * <a href="http://www.theora.org/">Theora</a>, a free video codec. + * Theora is derived from On2's VP3 codec with improved integration with + * Ogg multimedia formats by <a href="http://www.xiph.org/">Xiph.Org</a>. + * + * \section overview Overview + * + * This library will both decode and encode theora packets to/from raw YUV + * frames. In either case, the packets will most likely either come from or + * need to be embedded in an Ogg stream. Use + * <a href="http://xiph.org/ogg/">libogg</a> or + * <a href="http://www.annodex.net/software/liboggz/index.html">liboggz</a> + * to extract/package these packets. + * + * \section decoding Decoding Process + * + * Decoding can be separated into the following steps: + * -# initialise theora_info and theora_comment structures using + * theora_info_init() and theora_comment_init(): + \verbatim + theora_info info; + theora_comment comment; + + theora_info_init(&info); + theora_comment_init(&comment); + \endverbatim + * -# retrieve header packets from Ogg stream (there should be 3) and decode + * into theora_info and theora_comment structures using + * theora_decode_header(). See \ref identification for more information on + * identifying which packets are theora packets. + \verbatim + int i; + for (i = 0; i < 3; i++) + { + (get a theora packet "op" from the Ogg stream) + theora_decode_header(&info, &comment, op); + } + \endverbatim + * -# initialise the decoder based on the information retrieved into the + * theora_info struct by theora_decode_header(). You will need a + * theora_state struct. + \verbatim + theora_state state; + + theora_decode_init(&state, &info); + \endverbatim + * -# pass in packets and retrieve decoded frames! See the yuv_buffer + * documentation for information on how to retrieve raw YUV data. + \verbatim + yuf_buffer buffer; + while (last packet was not e_o_s) { + (get a theora packet "op" from the Ogg stream) + theora_decode_packetin(&state, op); + theora_decode_YUVout(&state, &buffer); + } + \endverbatim + * + * + * \subsection identification Identifying Theora Packets + * + * All streams inside an Ogg file have a unique serial_no attached to the + * stream. Typically, you will want to + * - retrieve the serial_no for each b_o_s (beginning of stream) page + * encountered within the Ogg file; + * - test the first (only) packet on that page to determine if it is a theora + * packet; + * - once you have found a theora b_o_s page then use the retrieved serial_no + * to identify future packets belonging to the same theora stream. + * + * Note that you \e cannot use theora_packet_isheader() to determine if a + * packet is a theora packet or not, as this function does not perform any + * checking beyond whether a header bit is present. Instead, use the + * theora_decode_header() function and check the return value; or examine the + * header bytes at the beginning of the Ogg page. + */ + + +/** \defgroup oldfuncs Legacy pre-1.0 C API */ +/* @{ */ + +/** + * A YUV buffer for passing uncompressed frames to and from the codec. + * This holds a Y'CbCr frame in planar format. The CbCr planes can be + * subsampled and have their own separate dimensions and row stride + * offsets. Note that the strides may be negative in some + * configurations. For theora the width and height of the largest plane + * must be a multiple of 16. The actual meaningful picture size and + * offset are stored in the theora_info structure; frames returned by + * the decoder may need to be cropped for display. + * + * All samples are 8 bits. Within each plane samples are ordered by + * row from the top of the frame to the bottom. Within each row samples + * are ordered from left to right. + * + * During decode, the yuv_buffer struct is allocated by the user, but all + * fields (including luma and chroma pointers) are filled by the library. + * These pointers address library-internal memory and their contents should + * not be modified. + * + * Conversely, during encode the user allocates the struct and fills out all + * fields. The user also manages the data addressed by the luma and chroma + * pointers. See the encoder_example.c and dump_video.c example files in + * theora/examples/ for more information. + */ +typedef struct { + int y_width; /**< Width of the Y' luminance plane */ + int y_height; /**< Height of the luminance plane */ + int y_stride; /**< Offset in bytes between successive rows */ + + int uv_width; /**< Width of the Cb and Cr chroma planes */ + int uv_height; /**< Height of the chroma planes */ + int uv_stride; /**< Offset between successive chroma rows */ + unsigned char *y; /**< Pointer to start of luminance data */ + unsigned char *u; /**< Pointer to start of Cb data */ + unsigned char *v; /**< Pointer to start of Cr data */ + +} yuv_buffer; + +/** + * A Colorspace. + */ +typedef enum { + OC_CS_UNSPECIFIED, /**< The colorspace is unknown or unspecified */ + OC_CS_ITU_REC_470M, /**< This is the best option for 'NTSC' content */ + OC_CS_ITU_REC_470BG, /**< This is the best option for 'PAL' content */ + OC_CS_NSPACES /**< This marks the end of the defined colorspaces */ +} theora_colorspace; + +/** + * A Chroma subsampling + * + * These enumerate the available chroma subsampling options supported + * by the theora format. See Section 4.4 of the specification for + * exact definitions. + */ +typedef enum { + OC_PF_420, /**< Chroma subsampling by 2 in each direction (4:2:0) */ + OC_PF_RSVD, /**< Reserved value */ + OC_PF_422, /**< Horizonatal chroma subsampling by 2 (4:2:2) */ + OC_PF_444, /**< No chroma subsampling at all (4:4:4) */ +} theora_pixelformat; + +/** + * Theora bitstream info. + * Contains the basic playback parameters for a stream, + * corresponding to the initial 'info' header packet. + * + * Encoded theora frames must be a multiple of 16 in width and height. + * To handle other frame sizes, a crop rectangle is specified in + * frame_height and frame_width, offset_x and * offset_y. The offset + * and size should still be a multiple of 2 to avoid chroma sampling + * shifts. Offset values in this structure are measured from the + * upper left of the image. + * + * Frame rate, in frames per second, is stored as a rational + * fraction. Aspect ratio is also stored as a rational fraction, and + * refers to the aspect ratio of the frame pixels, not of the + * overall frame itself. + * + * See <a href="http://svn.xiph.org/trunk/theora/examples/encoder_example.c"> + * examples/encoder_example.c</a> for usage examples of the + * other paramters and good default settings for the encoder parameters. + */ +typedef struct { + ogg_uint32_t width; /**< encoded frame width */ + ogg_uint32_t height; /**< encoded frame height */ + ogg_uint32_t frame_width; /**< display frame width */ + ogg_uint32_t frame_height; /**< display frame height */ + ogg_uint32_t offset_x; /**< horizontal offset of the displayed frame */ + ogg_uint32_t offset_y; /**< vertical offset of the displayed frame */ + ogg_uint32_t fps_numerator; /**< frame rate numerator **/ + ogg_uint32_t fps_denominator; /**< frame rate denominator **/ + ogg_uint32_t aspect_numerator; /**< pixel aspect ratio numerator */ + ogg_uint32_t aspect_denominator; /**< pixel aspect ratio denominator */ + theora_colorspace colorspace; /**< colorspace */ + int target_bitrate; /**< nominal bitrate in bits per second */ + int quality; /**< Nominal quality setting, 0-63 */ + int quick_p; /**< Quick encode/decode */ + + /* decode only */ + unsigned char version_major; + unsigned char version_minor; + unsigned char version_subminor; + + void *codec_setup; + + /* encode only */ + int dropframes_p; + int keyframe_auto_p; + ogg_uint32_t keyframe_frequency; + ogg_uint32_t keyframe_frequency_force; /* also used for decode init to + get granpos shift correct */ + ogg_uint32_t keyframe_data_target_bitrate; + ogg_int32_t keyframe_auto_threshold; + ogg_uint32_t keyframe_mindistance; + ogg_int32_t noise_sensitivity; + ogg_int32_t sharpness; + + theora_pixelformat pixelformat; /**< chroma subsampling mode to expect */ + +} theora_info; + +/** Codec internal state and context. + */ +typedef struct{ + theora_info *i; + ogg_int64_t granulepos; + + void *internal_encode; + void *internal_decode; + +} theora_state; + +/** + * Comment header metadata. + * + * This structure holds the in-stream metadata corresponding to + * the 'comment' header packet. + * + * Meta data is stored as a series of (tag, value) pairs, in + * length-encoded string vectors. The first occurence of the + * '=' character delimits the tag and value. A particular tag + * may occur more than once. The character set encoding for + * the strings is always UTF-8, but the tag names are limited + * to case-insensitive ASCII. See the spec for details. + * + * In filling in this structure, theora_decode_header() will + * null-terminate the user_comment strings for safety. However, + * the bitstream format itself treats them as 8-bit clean, + * and so the length array should be treated as authoritative + * for their length. + */ +typedef struct theora_comment{ + char **user_comments; /**< An array of comment string vectors */ + int *comment_lengths; /**< An array of corresponding string vector lengths in bytes */ + int comments; /**< The total number of comment string vectors */ + char *vendor; /**< The vendor string identifying the encoder, null terminated */ + +} theora_comment; + + +/**\name theora_control() codes */ +/* \anchor decctlcodes_old + * These are the available request codes for theora_control() + * when called with a decoder instance. + * By convention decoder control codes are odd, to distinguish + * them from \ref encctlcodes_old "encoder control codes" which + * are even. + * + * Note that since the 1.0 release, both the legacy and the final + * implementation accept all the same control codes, but only the + * final API declares the newer codes. + * + * Keep any experimental or vendor-specific values above \c 0x8000.*/ + +/*@{*/ + +/**Get the maximum post-processing level. + * The decoder supports a post-processing filter that can improve + * the appearance of the decoded images. This returns the highest + * level setting for this post-processor, corresponding to maximum + * improvement and computational expense. + */ +#define TH_DECCTL_GET_PPLEVEL_MAX (1) + +/**Set the post-processing level. + * Sets the level of post-processing to use when decoding the + * compressed stream. This must be a value between zero (off) + * and the maximum returned by TH_DECCTL_GET_PPLEVEL_MAX. + */ +#define TH_DECCTL_SET_PPLEVEL (3) + +/**Sets the maximum distance between key frames. + * This can be changed during an encode, but will be bounded by + * <tt>1<<th_info#keyframe_granule_shift</tt>. + * If it is set before encoding begins, th_info#keyframe_granule_shift will + * be enlarged appropriately. + * + * \param[in] buf <tt>ogg_uint32_t</tt>: The maximum distance between key + * frames. + * \param[out] buf <tt>ogg_uint32_t</tt>: The actual maximum distance set. + * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>. + * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(ogg_uint32_t)</tt>. + * \retval OC_IMPL Not supported by this implementation.*/ +#define TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE (4) + +/**Set the granule position. + * Call this after a seek, to update the internal granulepos + * in the decoder, to insure that subsequent frames are marked + * properly. If you track timestamps yourself and do not use + * the granule postion returned by the decoder, then you do + * not need to use this control. + */ +#define TH_DECCTL_SET_GRANPOS (5) + +/**\anchor encctlcodes_old */ + +/**Sets the quantization parameters to use. + * The parameters are copied, not stored by reference, so they can be freed + * after this call. + * <tt>NULL</tt> may be specified to revert to the default parameters. + * + * \param[in] buf #th_quant_info + * \retval OC_FAULT \a theora_state is <tt>NULL</tt>. + * \retval OC_EINVAL Encoding has already begun, the quantization parameters + * are not acceptable to this version of the encoder, + * \a buf is <tt>NULL</tt> and \a buf_sz is not zero, + * or \a buf is non-<tt>NULL</tt> and \a buf_sz is + * not <tt>sizeof(#th_quant_info)</tt>. + * \retval OC_IMPL Not supported by this implementation.*/ +#define TH_ENCCTL_SET_QUANT_PARAMS (2) + +/**Disables any encoder features that would prevent lossless transcoding back + * to VP3. + * This primarily means disabling block-level QI values and not using 4MV mode + * when any of the luma blocks in a macro block are not coded. + * It also includes using the VP3 quantization tables and Huffman codes; if you + * set them explicitly after calling this function, the resulting stream will + * not be VP3-compatible. + * If you enable VP3-compatibility when encoding 4:2:2 or 4:4:4 source + * material, or when using a picture region smaller than the full frame (e.g. + * a non-multiple-of-16 width or height), then non-VP3 bitstream features will + * still be disabled, but the stream will still not be VP3-compatible, as VP3 + * was not capable of encoding such formats. + * If you call this after encoding has already begun, then the quantization + * tables and codebooks cannot be changed, but the frame-level features will + * be enabled or disabled as requested. + * + * \param[in] buf <tt>int</tt>: a non-zero value to enable VP3 compatibility, + * or 0 to disable it (the default). + * \param[out] buf <tt>int</tt>: 1 if all bitstream features required for + * VP3-compatibility could be set, and 0 otherwise. + * The latter will be returned if the pixel format is not + * 4:2:0, the picture region is smaller than the full frame, + * or if encoding has begun, preventing the quantization + * tables and codebooks from being set. + * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>. + * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>. + * \retval OC_IMPL Not supported by this implementation.*/ +#define TH_ENCCTL_SET_VP3_COMPATIBLE (10) + +/**Gets the maximum speed level. + * Higher speed levels favor quicker encoding over better quality per bit. + * Depending on the encoding mode, and the internal algorithms used, quality + * may actually improve, but in this case bitrate will also likely increase. + * In any case, overall rate/distortion performance will probably decrease. + * The maximum value, and the meaning of each value, may change depending on + * the current encoding mode (VBR vs. CQI, etc.). + * + * \param[out] buf int: The maximum encoding speed level. + * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>. + * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>. + * \retval OC_IMPL Not supported by this implementation in the current + * encoding mode.*/ +#define TH_ENCCTL_GET_SPLEVEL_MAX (12) + +/**Sets the speed level. + * By default a speed value of 1 is used. + * + * \param[in] buf int: The new encoding speed level. + * 0 is slowest, larger values use less CPU. + * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>. + * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>, or the + * encoding speed level is out of bounds. + * The maximum encoding speed level may be + * implementation- and encoding mode-specific, and can be + * obtained via #TH_ENCCTL_GET_SPLEVEL_MAX. + * \retval OC_IMPL Not supported by this implementation in the current + * encoding mode.*/ +#define TH_ENCCTL_SET_SPLEVEL (14) + +/*@}*/ + +#define OC_FAULT -1 /**< General failure */ +#define OC_EINVAL -10 /**< Library encountered invalid internal data */ +#define OC_DISABLED -11 /**< Requested action is disabled */ +#define OC_BADHEADER -20 /**< Header packet was corrupt/invalid */ +#define OC_NOTFORMAT -21 /**< Packet is not a theora packet */ +#define OC_VERSION -22 /**< Bitstream version is not handled */ +#define OC_IMPL -23 /**< Feature or action not implemented */ +#define OC_BADPACKET -24 /**< Packet is corrupt */ +#define OC_NEWPACKET -25 /**< Packet is an (ignorable) unhandled extension */ +#define OC_DUPFRAME 1 /**< Packet is a dropped frame */ + +/** + * Retrieve a human-readable string to identify the encoder vendor and version. + * \returns A version string. + */ +extern const char *theora_version_string(void); + +/** + * Retrieve a 32-bit version number. + * This number is composed of a 16-bit major version, 8-bit minor version + * and 8 bit sub-version, composed as follows: +<pre> + (VERSION_MAJOR<<16) + (VERSION_MINOR<<8) + (VERSION_SUB) +</pre> +* \returns The version number. +*/ +extern ogg_uint32_t theora_version_number(void); + +/** + * Initialize the theora encoder. + * \param th The theora_state handle to initialize for encoding. + * \param ti A theora_info struct filled with the desired encoding parameters. + * \retval 0 Success + */ +extern int theora_encode_init(theora_state *th, theora_info *ti); + +/** + * Submit a YUV buffer to the theora encoder. + * \param t A theora_state handle previously initialized for encoding. + * \param yuv A buffer of YUV data to encode. Note that both the yuv_buffer + * struct and the luma/chroma buffers within should be allocated by + * the user. + * \retval OC_EINVAL Encoder is not ready, or is finished. + * \retval -1 The size of the given frame differs from those previously input + * \retval 0 Success + */ +extern int theora_encode_YUVin(theora_state *t, yuv_buffer *yuv); + +/** + * Request the next packet of encoded video. + * The encoded data is placed in a user-provided ogg_packet structure. + * \param t A theora_state handle previously initialized for encoding. + * \param last_p whether this is the last packet the encoder should produce. + * \param op An ogg_packet structure to fill. libtheora will set all + * elements of this structure, including a pointer to encoded + * data. The memory for the encoded data is owned by libtheora. + * \retval 0 No internal storage exists OR no packet is ready + * \retval -1 The encoding process has completed + * \retval 1 Success + */ +extern int theora_encode_packetout( theora_state *t, int last_p, + ogg_packet *op); + +/** + * Request a packet containing the initial header. + * A pointer to the header data is placed in a user-provided ogg_packet + * structure. + * \param t A theora_state handle previously initialized for encoding. + * \param op An ogg_packet structure to fill. libtheora will set all + * elements of this structure, including a pointer to the header + * data. The memory for the header data is owned by libtheora. + * \retval 0 Success + */ +extern int theora_encode_header(theora_state *t, ogg_packet *op); + +/** + * Request a comment header packet from provided metadata. + * A pointer to the comment data is placed in a user-provided ogg_packet + * structure. + * \param tc A theora_comment structure filled with the desired metadata + * \param op An ogg_packet structure to fill. libtheora will set all + * elements of this structure, including a pointer to the encoded + * comment data. The memory for the comment data is owned by + * libtheora. + * \retval 0 Success + */ +extern int theora_encode_comment(theora_comment *tc, ogg_packet *op); + +/** + * Request a packet containing the codebook tables for the stream. + * A pointer to the codebook data is placed in a user-provided ogg_packet + * structure. + * \param t A theora_state handle previously initialized for encoding. + * \param op An ogg_packet structure to fill. libtheora will set all + * elements of this structure, including a pointer to the codebook + * data. The memory for the header data is owned by libtheora. + * \retval 0 Success + */ +extern int theora_encode_tables(theora_state *t, ogg_packet *op); + +/** + * Decode an Ogg packet, with the expectation that the packet contains + * an initial header, comment data or codebook tables. + * + * \param ci A theora_info structure to fill. This must have been previously + * initialized with theora_info_init(). If \a op contains an initial + * header, theora_decode_header() will fill \a ci with the + * parsed header values. If \a op contains codebook tables, + * theora_decode_header() will parse these and attach an internal + * representation to \a ci->codec_setup. + * \param cc A theora_comment structure to fill. If \a op contains comment + * data, theora_decode_header() will fill \a cc with the parsed + * comments. + * \param op An ogg_packet structure which you expect contains an initial + * header, comment data or codebook tables. + * + * \retval OC_BADHEADER \a op is NULL; OR the first byte of \a op->packet + * has the signature of an initial packet, but op is + * not a b_o_s packet; OR this packet has the signature + * of an initial header packet, but an initial header + * packet has already been seen; OR this packet has the + * signature of a comment packet, but the initial header + * has not yet been seen; OR this packet has the signature + * of a comment packet, but contains invalid data; OR + * this packet has the signature of codebook tables, + * but the initial header or comments have not yet + * been seen; OR this packet has the signature of codebook + * tables, but contains invalid data; + * OR the stream being decoded has a compatible version + * but this packet does not have the signature of a + * theora initial header, comments, or codebook packet + * \retval OC_VERSION The packet data of \a op is an initial header with + * a version which is incompatible with this version of + * libtheora. + * \retval OC_NEWPACKET the stream being decoded has an incompatible (future) + * version and contains an unknown signature. + * \retval 0 Success + * + * \note The normal usage is that theora_decode_header() be called on the + * first three packets of a theora logical bitstream in succession. + */ +extern int theora_decode_header(theora_info *ci, theora_comment *cc, + ogg_packet *op); + +/** + * Initialize a theora_state handle for decoding. + * \param th The theora_state handle to initialize. + * \param c A theora_info struct filled with the desired decoding parameters. + * This is of course usually obtained from a previous call to + * theora_decode_header(). + * \retval 0 Success + */ +extern int theora_decode_init(theora_state *th, theora_info *c); + +/** + * Input a packet containing encoded data into the theora decoder. + * \param th A theora_state handle previously initialized for decoding. + * \param op An ogg_packet containing encoded theora data. + * \retval 0 Success + * \retval OC_BADPACKET \a op does not contain encoded video data + */ +extern int theora_decode_packetin(theora_state *th,ogg_packet *op); + +/** + * Output the next available frame of decoded YUV data. + * \param th A theora_state handle previously initialized for decoding. + * \param yuv A yuv_buffer in which libtheora should place the decoded data. + * Note that the buffer struct itself is allocated by the user, but + * that the luma and chroma pointers will be filled in by the + * library. Also note that these luma and chroma regions should be + * considered read-only by the user. + * \retval 0 Success + */ +extern int theora_decode_YUVout(theora_state *th,yuv_buffer *yuv); + +/** + * Report whether a theora packet is a header or not + * This function does no verification beyond checking the header + * flag bit so it should not be used for bitstream identification; + * use theora_decode_header() for that. + * + * \param op An ogg_packet containing encoded theora data. + * \retval 1 The packet is a header packet + * \retval 0 The packet is not a header packet (and so contains frame data) + * + * Thus function was added in the 1.0alpha4 release. + */ +extern int theora_packet_isheader(ogg_packet *op); + +/** + * Report whether a theora packet is a keyframe or not + * + * \param op An ogg_packet containing encoded theora data. + * \retval 1 The packet contains a keyframe image + * \retval 0 The packet is contains an interframe delta + * \retval -1 The packet is not an image data packet at all + * + * Thus function was added in the 1.0alpha4 release. + */ +extern int theora_packet_iskeyframe(ogg_packet *op); + +/** + * Report the granulepos shift radix + * + * When embedded in Ogg, Theora uses a two-part granulepos, + * splitting the 64-bit field into two pieces. The more-significant + * section represents the frame count at the last keyframe, + * and the less-significant section represents the count of + * frames since the last keyframe. In this way the overall + * field is still non-decreasing with time, but usefully encodes + * a pointer to the last keyframe, which is necessary for + * correctly restarting decode after a seek. + * + * This function reports the number of bits used to represent + * the distance to the last keyframe, and thus how the granulepos + * field must be shifted or masked to obtain the two parts. + * + * Since libtheora returns compressed data in an ogg_packet + * structure, this may be generally useful even if the Theora + * packets are not being used in an Ogg container. + * + * \param ti A previously initialized theora_info struct + * \returns The bit shift dividing the two granulepos fields + * + * This function was added in the 1.0alpha5 release. + */ +int theora_granule_shift(theora_info *ti); + +/** + * Convert a granulepos to an absolute frame index, starting at 0. + * The granulepos is interpreted in the context of a given theora_state handle. + * + * Note that while the granulepos encodes the frame count (i.e. starting + * from 1) this call returns the frame index, starting from zero. Thus + * One can calculate the presentation time by multiplying the index by + * the rate. + * + * \param th A previously initialized theora_state handle (encode or decode) + * \param granulepos The granulepos to convert. + * \returns The frame index corresponding to \a granulepos. + * \retval -1 The given granulepos is undefined (i.e. negative) + * + * Thus function was added in the 1.0alpha4 release. + */ +extern ogg_int64_t theora_granule_frame(theora_state *th,ogg_int64_t granulepos); + +/** + * Convert a granulepos to absolute time in seconds. The granulepos is + * interpreted in the context of a given theora_state handle, and gives + * the end time of a frame's presentation as used in Ogg mux ordering. + * + * \param th A previously initialized theora_state handle (encode or decode) + * \param granulepos The granulepos to convert. + * \returns The absolute time in seconds corresponding to \a granulepos. + * This is the "end time" for the frame, or the latest time it should + * be displayed. + * It is not the presentation time. + * \retval -1. The given granulepos is undefined (i.e. negative), or + * \retval -1. The function has been disabled because floating + * point support is not available. + */ +extern double theora_granule_time(theora_state *th,ogg_int64_t granulepos); + +/** + * Initialize a theora_info structure. All values within the given theora_info + * structure are initialized, and space is allocated within libtheora for + * internal codec setup data. + * \param c A theora_info struct to initialize. + */ +extern void theora_info_init(theora_info *c); + +/** + * Clear a theora_info structure. All values within the given theora_info + * structure are cleared, and associated internal codec setup data is freed. + * \param c A theora_info struct to initialize. + */ +extern void theora_info_clear(theora_info *c); + +/** + * Free all internal data associated with a theora_state handle. + * \param t A theora_state handle. + */ +extern void theora_clear(theora_state *t); + +/** + * Initialize an allocated theora_comment structure + * \param tc An allocated theora_comment structure + **/ +extern void theora_comment_init(theora_comment *tc); + +/** + * Add a comment to an initialized theora_comment structure + * \param tc A previously initialized theora comment structure + * \param comment A null-terminated string encoding the comment in the form + * "TAG=the value" + * + * Neither theora_comment_add() nor theora_comment_add_tag() support + * comments containing null values, although the bitstream format + * supports this. To add such comments you will need to manipulate + * the theora_comment structure directly. + **/ + +extern void theora_comment_add(theora_comment *tc, char *comment); + +/** + * Add a comment to an initialized theora_comment structure. + * \param tc A previously initialized theora comment structure + * \param tag A null-terminated string containing the tag + * associated with the comment. + * \param value The corresponding value as a null-terminated string + * + * Neither theora_comment_add() nor theora_comment_add_tag() support + * comments containing null values, although the bitstream format + * supports this. To add such comments you will need to manipulate + * the theora_comment structure directly. + **/ +extern void theora_comment_add_tag(theora_comment *tc, + char *tag, char *value); + +/** + * Look up a comment value by tag. + * \param tc Tn initialized theora_comment structure + * \param tag The tag to look up + * \param count The instance of the tag. The same tag can appear multiple + * times, each with a distinct and ordered value, so an index + * is required to retrieve them all. + * \returns A pointer to the queried tag's value + * \retval NULL No matching tag is found + * + * \note Use theora_comment_query_count() to get the legal range for the + * count parameter. + **/ + +extern char *theora_comment_query(theora_comment *tc, char *tag, int count); + +/** Look up the number of instances of a tag. + * \param tc An initialized theora_comment structure + * \param tag The tag to look up + * \returns The number on instances of a particular tag. + * + * Call this first when querying for a specific tag and then interate + * over the number of instances with separate calls to + * theora_comment_query() to retrieve all instances in order. + **/ +extern int theora_comment_query_count(theora_comment *tc, char *tag); + +/** + * Clear an allocated theora_comment struct so that it can be freed. + * \param tc An allocated theora_comment structure. + **/ +extern void theora_comment_clear(theora_comment *tc); + +/**Encoder control function. + * This is used to provide advanced control the encoding process. + * \param th A #theora_state handle. + * \param req The control code to process. + * See \ref encctlcodes_old "the list of available + * control codes" for details. + * \param buf The parameters for this control code. + * \param buf_sz The size of the parameter buffer.*/ +extern int theora_control(theora_state *th,int req,void *buf,size_t buf_sz); + +/* @} */ /* end oldfuncs doxygen group */ + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif /* _O_THEORA_H_ */ |