mirror of
https://github.com/godotengine/godot.git
synced 2024-12-03 09:52:18 +08:00
785 lines
32 KiB
C
785 lines
32 KiB
C
/********************************************************************
|
|
* *
|
|
* 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_ */
|