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/*
* copyright ( c ) 2001 Fabrice Bellard
*
* This file is part of FFmpeg .
*
* FFmpeg is free software ; you can redistribute it and / or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation ; either
* version 2.1 of the License , or ( at your option ) any later version .
*
* FFmpeg is distributed in the hope that it will be useful ,
* but WITHOUT ANY WARRANTY ; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE . See the GNU
* Lesser General Public License for more details .
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg ; if not , write to the Free Software
* Foundation , Inc . , 51 Franklin Street , Fifth Floor , Boston , MA 02110 - 1301 USA
*/
# ifndef AVCODEC_AVCODEC_H
# define AVCODEC_AVCODEC_H
/**
* @ file
* @ ingroup libavc
* Libavcodec external API header
*/
# include "libavutil/samplefmt.h"
# include "libavutil/attributes.h"
# include "libavutil/avutil.h"
# include "libavutil/buffer.h"
# include "libavutil/dict.h"
# include "libavutil/frame.h"
# include "libavutil/log.h"
# include "libavutil/pixfmt.h"
# include "libavutil/rational.h"
# include "codec.h"
# include "codec_desc.h"
# include "codec_par.h"
# include "codec_id.h"
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# include "defs.h"
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# include "packet.h"
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# include "version_major.h"
# ifndef HAVE_AV_CONFIG_H
/* When included as part of the ffmpeg build, only include the major version
* to avoid unnecessary rebuilds . When included externally , keep including
* the full version information . */
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# include "version.h"
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# endif
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/**
* @ defgroup libavc libavcodec
* Encoding / Decoding Library
*
* @ {
*
* @ defgroup lavc_decoding Decoding
* @ {
* @ }
*
* @ defgroup lavc_encoding Encoding
* @ {
* @ }
*
* @ defgroup lavc_codec Codecs
* @ {
* @ defgroup lavc_codec_native Native Codecs
* @ {
* @ }
* @ defgroup lavc_codec_wrappers External library wrappers
* @ {
* @ }
* @ defgroup lavc_codec_hwaccel Hardware Accelerators bridge
* @ {
* @ }
* @ }
* @ defgroup lavc_internal Internal
* @ {
* @ }
* @ }
*/
/**
* @ ingroup libavc
* @ defgroup lavc_encdec send / receive encoding and decoding API overview
* @ {
*
* The avcodec_send_packet ( ) / avcodec_receive_frame ( ) / avcodec_send_frame ( ) /
* avcodec_receive_packet ( ) functions provide an encode / decode API , which
* decouples input and output .
*
* The API is very similar for encoding / decoding and audio / video , and works as
* follows :
* - Set up and open the AVCodecContext as usual .
* - Send valid input :
* - For decoding , call avcodec_send_packet ( ) to give the decoder raw
* compressed data in an AVPacket .
* - For encoding , call avcodec_send_frame ( ) to give the encoder an AVFrame
* containing uncompressed audio or video .
*
* In both cases , it is recommended that AVPackets and AVFrames are
* refcounted , or libavcodec might have to copy the input data . ( libavformat
* always returns refcounted AVPackets , and av_frame_get_buffer ( ) allocates
* refcounted AVFrames . )
* - Receive output in a loop . Periodically call one of the avcodec_receive_ * ( )
* functions and process their output :
* - For decoding , call avcodec_receive_frame ( ) . On success , it will return
* an AVFrame containing uncompressed audio or video data .
* - For encoding , call avcodec_receive_packet ( ) . On success , it will return
* an AVPacket with a compressed frame .
*
* Repeat this call until it returns AVERROR ( EAGAIN ) or an error . The
* AVERROR ( EAGAIN ) return value means that new input data is required to
* return new output . In this case , continue with sending input . For each
* input frame / packet , the codec will typically return 1 output frame / packet ,
* but it can also be 0 or more than 1.
*
* At the beginning of decoding or encoding , the codec might accept multiple
* input frames / packets without returning a frame , until its internal buffers
* are filled . This situation is handled transparently if you follow the steps
* outlined above .
*
* In theory , sending input can result in EAGAIN - this should happen only if
* not all output was received . You can use this to structure alternative decode
* or encode loops other than the one suggested above . For example , you could
* try sending new input on each iteration , and try to receive output if that
* returns EAGAIN .
*
* End of stream situations . These require " flushing " ( aka draining ) the codec ,
* as the codec might buffer multiple frames or packets internally for
* performance or out of necessity ( consider B - frames ) .
* This is handled as follows :
* - Instead of valid input , send NULL to the avcodec_send_packet ( ) ( decoding )
* or avcodec_send_frame ( ) ( encoding ) functions . This will enter draining
* mode .
* - Call avcodec_receive_frame ( ) ( decoding ) or avcodec_receive_packet ( )
* ( encoding ) in a loop until AVERROR_EOF is returned . The functions will
* not return AVERROR ( EAGAIN ) , unless you forgot to enter draining mode .
* - Before decoding can be resumed again , the codec has to be reset with
* avcodec_flush_buffers ( ) .
*
* Using the API as outlined above is highly recommended . But it is also
* possible to call functions outside of this rigid schema . For example , you can
* call avcodec_send_packet ( ) repeatedly without calling
* avcodec_receive_frame ( ) . In this case , avcodec_send_packet ( ) will succeed
* until the codec ' s internal buffer has been filled up ( which is typically of
* size 1 per output frame , after initial input ) , and then reject input with
* AVERROR ( EAGAIN ) . Once it starts rejecting input , you have no choice but to
* read at least some output .
*
* Not all codecs will follow a rigid and predictable dataflow ; the only
* guarantee is that an AVERROR ( EAGAIN ) return value on a send / receive call on
* one end implies that a receive / send call on the other end will succeed , or
* at least will not fail with AVERROR ( EAGAIN ) . In general , no codec will
* permit unlimited buffering of input or output .
*
* A codec is not allowed to return AVERROR ( EAGAIN ) for both sending and receiving . This
* would be an invalid state , which could put the codec user into an endless
* loop . The API has no concept of time either : it cannot happen that trying to
* do avcodec_send_packet ( ) results in AVERROR ( EAGAIN ) , but a repeated call 1 second
* later accepts the packet ( with no other receive / flush API calls involved ) .
* The API is a strict state machine , and the passage of time is not supposed
* to influence it . Some timing - dependent behavior might still be deemed
* acceptable in certain cases . But it must never result in both send / receive
* returning EAGAIN at the same time at any point . It must also absolutely be
* avoided that the current state is " unstable " and can " flip-flop " between
* the send / receive APIs allowing progress . For example , it ' s not allowed that
* the codec randomly decides that it actually wants to consume a packet now
* instead of returning a frame , after it just returned AVERROR ( EAGAIN ) on an
* avcodec_send_packet ( ) call .
* @ }
*/
/**
* @ defgroup lavc_core Core functions / structures .
* @ ingroup libavc
*
* Basic definitions , functions for querying libavcodec capabilities ,
* allocating core structures , etc .
* @ {
*/
/**
* @ ingroup lavc_encoding
* minimum encoding buffer size
* Used to avoid some checks during header writing .
*/
# define AV_INPUT_BUFFER_MIN_SIZE 16384
/**
* @ ingroup lavc_encoding
*/
typedef struct RcOverride {
int start_frame ;
int end_frame ;
int qscale ; // If this is 0 then quality_factor will be used instead.
float quality_factor ;
} RcOverride ;
/* encoding support
These flags can be passed in AVCodecContext . flags before initialization .
Note : Not everything is supported yet .
*/
/**
* Allow decoders to produce frames with data planes that are not aligned
* to CPU requirements ( e . g . due to cropping ) .
*/
# define AV_CODEC_FLAG_UNALIGNED (1 << 0)
/**
* Use fixed qscale .
*/
# define AV_CODEC_FLAG_QSCALE (1 << 1)
/**
* 4 MV per MB allowed / advanced prediction for H .263 .
*/
# define AV_CODEC_FLAG_4MV (1 << 2)
/**
* Output even those frames that might be corrupted .
*/
# define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
/**
* Use qpel MC .
*/
# define AV_CODEC_FLAG_QPEL (1 << 4)
/**
* Don ' t output frames whose parameters differ from first
* decoded frame in stream .
*/
# define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
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/**
* Request the encoder to output reconstructed frames , i . e . \ frames that would
* be produced by decoding the encoded bistream . These frames may be retrieved
* by calling avcodec_receive_frame ( ) immediately after a successful call to
* avcodec_receive_packet ( ) .
*
* Should only be used with encoders flagged with the
* @ ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability .
*/
# define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
/**
* @ par decoding
* Request the decoder to propagate each packets AVPacket . opaque and
* AVPacket . opaque_ref to its corresponding output AVFrame .
*
* @ par encoding :
* Request the encoder to propagate each frame ' s AVFrame . opaque and
* AVFrame . opaque_ref values to its corresponding output AVPacket .
*
* @ par
* May only be set on encoders that have the
* @ ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag .
*
* @ note
* While in typical cases one input frame produces exactly one output packet
* ( perhaps after a delay ) , in general the mapping of frames to packets is
* M - to - N , so
* - Any number of input frames may be associated with any given output packet .
* This includes zero - e . g . some encoders may output packets that carry only
* metadata about the whole stream .
* - A given input frame may be associated with any number of output packets .
* Again this includes zero - e . g . some encoders may drop frames under certain
* conditions .
* .
* This implies that when using this flag , the caller must NOT assume that
* - a given input frame ' s opaques will necessarily appear on some output packet ;
* - every output packet will have some non - NULL opaque value .
* .
* When an output packet contains multiple frames , the opaque values will be
* taken from the first of those .
*
* @ note
* The converse holds for decoders , with frames and packets switched .
*/
# define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
/**
* Signal to the encoder that the values of AVFrame . duration are valid and
* should be used ( typically for transferring them to output packets ) .
*
* If this flag is not set , frame durations are ignored .
*/
# define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
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/**
* Use internal 2 pass ratecontrol in first pass mode .
*/
# define AV_CODEC_FLAG_PASS1 (1 << 9)
/**
* Use internal 2 pass ratecontrol in second pass mode .
*/
# define AV_CODEC_FLAG_PASS2 (1 << 10)
/**
* loop filter .
*/
# define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
/**
* Only decode / encode grayscale .
*/
# define AV_CODEC_FLAG_GRAY (1 << 13)
/**
* error [ ? ] variables will be set during encoding .
*/
# define AV_CODEC_FLAG_PSNR (1 << 15)
/**
* Use interlaced DCT .
*/
# define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
/**
* Force low delay .
*/
# define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
/**
* Place global headers in extradata instead of every keyframe .
*/
# define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
/**
* Use only bitexact stuff ( except ( I ) DCT ) .
*/
# define AV_CODEC_FLAG_BITEXACT (1 << 23)
/* Fx : Flag for H.263+ extra options */
/**
* H .263 advanced intra coding / MPEG - 4 AC prediction
*/
# define AV_CODEC_FLAG_AC_PRED (1 << 24)
/**
* interlaced motion estimation
*/
# define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
# define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
/**
* Allow non spec compliant speedup tricks .
*/
# define AV_CODEC_FLAG2_FAST (1 << 0)
/**
* Skip bitstream encoding .
*/
# define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
/**
* Place global headers at every keyframe instead of in extradata .
*/
# define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
/**
* Input bitstream might be truncated at a packet boundaries
* instead of only at frame boundaries .
*/
# define AV_CODEC_FLAG2_CHUNKS (1 << 15)
/**
* Discard cropping information from SPS .
*/
# define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
/**
* Show all frames before the first keyframe
*/
# define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
/**
* Export motion vectors through frame side data
*/
# define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
/**
* Do not skip samples and export skip information as frame side data
*/
# define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
/**
* Do not reset ASS ReadOrder field on flush ( subtitles decoding )
*/
# define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
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/**
* Generate / parse ICC profiles on encode / decode , as appropriate for the type of
* file . No effect on codecs which cannot contain embedded ICC profiles , or
* when compiled without support for lcms2 .
*/
# define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
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/* Exported side data.
These flags can be passed in AVCodecContext . export_side_data before initialization .
*/
/**
* Export motion vectors through frame side data
*/
# define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
/**
* Export encoder Producer Reference Time through packet side data
*/
# define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
/**
* Decoding only .
* Export the AVVideoEncParams structure through frame side data .
*/
# define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
/**
* Decoding only .
* Do not apply film grain , export it instead .
*/
# define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
/**
* The decoder will keep a reference to the frame and may reuse it later .
*/
# define AV_GET_BUFFER_FLAG_REF (1 << 0)
/**
* The encoder will keep a reference to the packet and may reuse it later .
*/
# define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
struct AVCodecInternal ;
/**
* main external API structure .
* New fields can be added to the end with minor version bumps .
* Removal , reordering and changes to existing fields require a major
* version bump .
* You can use AVOptions ( av_opt * / av_set / get * ( ) ) to access these fields from user
* applications .
* The name string for AVOptions options matches the associated command line
* parameter name and can be found in libavcodec / options_table . h
* The AVOption / command line parameter names differ in some cases from the C
* structure field names for historic reasons or brevity .
* sizeof ( AVCodecContext ) must not be used outside libav * .
*/
typedef struct AVCodecContext {
/**
* information on struct for av_log
* - set by avcodec_alloc_context3
*/
const AVClass * av_class ;
int log_level_offset ;
enum AVMediaType codec_type ; /* see AVMEDIA_TYPE_xxx */
const struct AVCodec * codec ;
enum AVCodecID codec_id ; /* see AV_CODEC_ID_xxx */
/**
* fourcc ( LSB first , so " ABCD " - > ( ' D ' < < 24 ) + ( ' C ' < < 16 ) + ( ' B ' < < 8 ) + ' A ' ) .
* This is used to work around some encoder bugs .
* A demuxer should set this to what is stored in the field used to identify the codec .
* If there are multiple such fields in a container then the demuxer should choose the one
* which maximizes the information about the used codec .
* If the codec tag field in a container is larger than 32 bits then the demuxer should
* remap the longer ID to 32 bits with a table or other structure . Alternatively a new
* extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
* first .
* - encoding : Set by user , if not then the default based on codec_id will be used .
* - decoding : Set by user , will be converted to uppercase by libavcodec during init .
*/
unsigned int codec_tag ;
void * priv_data ;
/**
* Private context used for internal data .
*
* Unlike priv_data , this is not codec - specific . It is used in general
* libavcodec functions .
*/
struct AVCodecInternal * internal ;
/**
* Private data of the user , can be used to carry app specific stuff .
* - encoding : Set by user .
* - decoding : Set by user .
*/
void * opaque ;
/**
* the average bitrate
* - encoding : Set by user ; unused for constant quantizer encoding .
* - decoding : Set by user , may be overwritten by libavcodec
* if this info is available in the stream
*/
int64_t bit_rate ;
/**
* number of bits the bitstream is allowed to diverge from the reference .
* the reference can be CBR ( for CBR pass1 ) or VBR ( for pass2 )
* - encoding : Set by user ; unused for constant quantizer encoding .
* - decoding : unused
*/
int bit_rate_tolerance ;
/**
* Global quality for codecs which cannot change it per frame .
* This should be proportional to MPEG - 1 / 2 / 4 qscale .
* - encoding : Set by user .
* - decoding : unused
*/
int global_quality ;
/**
* - encoding : Set by user .
* - decoding : unused
*/
int compression_level ;
# define FF_COMPRESSION_DEFAULT -1
/**
* AV_CODEC_FLAG_ * .
* - encoding : Set by user .
* - decoding : Set by user .
*/
int flags ;
/**
* AV_CODEC_FLAG2_ *
* - encoding : Set by user .
* - decoding : Set by user .
*/
int flags2 ;
/**
* some codecs need / can use extradata like Huffman tables .
* MJPEG : Huffman tables
* rv10 : additional flags
* MPEG - 4 : global headers ( they can be in the bitstream or here )
* The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
* than extradata_size to avoid problems if it is read with the bitstream reader .
* The bytewise contents of extradata must not depend on the architecture or CPU endianness .
* Must be allocated with the av_malloc ( ) family of functions .
* - encoding : Set / allocated / freed by libavcodec .
* - decoding : Set / allocated / freed by user .
*/
uint8_t * extradata ;
int extradata_size ;
/**
* This is the fundamental unit of time ( in seconds ) in terms
* of which frame timestamps are represented . For fixed - fps content ,
* timebase should be 1 / framerate and timestamp increments should be
* identically 1.
* This often , but not always is the inverse of the frame rate or field rate
* for video . 1 / time_base is not the average frame rate if the frame rate is not
* constant .
*
* Like containers , elementary streams also can store timestamps , 1 / time_base
* is the unit in which these timestamps are specified .
* As example of such codec time base see ISO / IEC 14496 - 2 : 2001 ( E )
* vop_time_increment_resolution and fixed_vop_rate
* ( fixed_vop_rate = = 0 implies that it is different from the framerate )
*
* - encoding : MUST be set by user .
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* - decoding : unused .
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*/
AVRational time_base ;
/**
* For some codecs , the time base is closer to the field rate than the frame rate .
* Most notably , H .264 and MPEG - 2 specify time_base as half of frame duration
* if no telecine is used . . .
*
* Set to time_base ticks per frame . Default 1 , e . g . , H .264 / MPEG - 2 set it to 2.
*/
int ticks_per_frame ;
/**
* Codec delay .
*
* Encoding : Number of frames delay there will be from the encoder input to
* the decoder output . ( we assume the decoder matches the spec )
* Decoding : Number of frames delay in addition to what a standard decoder
* as specified in the spec would produce .
*
* Video :
* Number of frames the decoded output will be delayed relative to the
* encoded input .
*
* Audio :
* For encoding , this field is unused ( see initial_padding ) .
*
* For decoding , this is the number of samples the decoder needs to
* output before the decoder ' s output is valid . When seeking , you should
* start decoding this many samples prior to your desired seek point .
*
* - encoding : Set by libavcodec .
* - decoding : Set by libavcodec .
*/
int delay ;
/* video only */
/**
* picture width / height .
*
* @ note Those fields may not match the values of the last
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* AVFrame output by avcodec_receive_frame ( ) due frame
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* reordering .
*
* - encoding : MUST be set by user .
* - decoding : May be set by the user before opening the decoder if known e . g .
* from the container . Some decoders will require the dimensions
* to be set by the caller . During decoding , the decoder may
* overwrite those values as required while parsing the data .
*/
int width , height ;
/**
* Bitstream width / height , may be different from width / height e . g . when
* the decoded frame is cropped before being output or lowres is enabled .
*
* @ note Those field may not match the value of the last
* AVFrame output by avcodec_receive_frame ( ) due frame
* reordering .
*
* - encoding : unused
* - decoding : May be set by the user before opening the decoder if known
* e . g . from the container . During decoding , the decoder may
* overwrite those values as required while parsing the data .
*/
int coded_width , coded_height ;
/**
* the number of pictures in a group of pictures , or 0 for intra_only
* - encoding : Set by user .
* - decoding : unused
*/
int gop_size ;
/**
* Pixel format , see AV_PIX_FMT_xxx .
* May be set by the demuxer if known from headers .
* May be overridden by the decoder if it knows better .
*
* @ note This field may not match the value of the last
* AVFrame output by avcodec_receive_frame ( ) due frame
* reordering .
*
* - encoding : Set by user .
* - decoding : Set by user if known , overridden by libavcodec while
* parsing the data .
*/
enum AVPixelFormat pix_fmt ;
/**
* If non NULL , ' draw_horiz_band ' is called by the libavcodec
* decoder to draw a horizontal band . It improves cache usage . Not
* all codecs can do that . You must check the codec capabilities
* beforehand .
* When multithreading is used , it may be called from multiple threads
* at the same time ; threads might draw different parts of the same AVFrame ,
* or multiple AVFrames , and there is no guarantee that slices will be drawn
* in order .
* The function is also used by hardware acceleration APIs .
* It is called at least once during frame decoding to pass
* the data needed for hardware render .
* In that mode instead of pixel data , AVFrame points to
* a structure specific to the acceleration API . The application
* reads the structure and can change some fields to indicate progress
* or mark state .
* - encoding : unused
* - decoding : Set by user .
* @ param height the height of the slice
* @ param y the y position of the slice
* @ param type 1 - > top field , 2 - > bottom field , 3 - > frame
* @ param offset offset into the AVFrame . data from which the slice should be read
*/
void ( * draw_horiz_band ) ( struct AVCodecContext * s ,
const AVFrame * src , int offset [ AV_NUM_DATA_POINTERS ] ,
int y , int type , int height ) ;
/**
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* Callback to negotiate the pixel format . Decoding only , may be set by the
* caller before avcodec_open2 ( ) .
*
* Called by some decoders to select the pixel format that will be used for
* the output frames . This is mainly used to set up hardware acceleration ,
* then the provided format list contains the corresponding hwaccel pixel
* formats alongside the " software " one . The software pixel format may also
* be retrieved from \ ref sw_pix_fmt .
*
* This callback will be called when the coded frame properties ( such as
* resolution , pixel format , etc . ) change and more than one output format is
* supported for those new properties . If a hardware pixel format is chosen
* and initialization for it fails , the callback may be called again
* immediately .
*
* This callback may be called from different threads if the decoder is
* multi - threaded , but not from more than one thread simultaneously .
*
* @ param fmt list of formats which may be used in the current
* configuration , terminated by AV_PIX_FMT_NONE .
* @ warning Behavior is undefined if the callback returns a value other
* than one of the formats in fmt or AV_PIX_FMT_NONE .
* @ return the chosen format or AV_PIX_FMT_NONE
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*/
enum AVPixelFormat ( * get_format ) ( struct AVCodecContext * s , const enum AVPixelFormat * fmt ) ;
/**
* maximum number of B - frames between non - B - frames
* Note : The output will be delayed by max_b_frames + 1 relative to the input .
* - encoding : Set by user .
* - decoding : unused
*/
int max_b_frames ;
/**
* qscale factor between IP and B - frames
* If > 0 then the last P - frame quantizer will be used ( q = lastp_q * factor + offset ) .
* If < 0 then normal ratecontrol will be done ( q = - normal_q * factor + offset ) .
* - encoding : Set by user .
* - decoding : unused
*/
float b_quant_factor ;
/**
* qscale offset between IP and B - frames
* - encoding : Set by user .
* - decoding : unused
*/
float b_quant_offset ;
/**
* Size of the frame reordering buffer in the decoder .
* For MPEG - 2 it is 1 IPB or 0 low delay IP .
* - encoding : Set by libavcodec .
* - decoding : Set by libavcodec .
*/
int has_b_frames ;
/**
* qscale factor between P - and I - frames
* If > 0 then the last P - frame quantizer will be used ( q = lastp_q * factor + offset ) .
* If < 0 then normal ratecontrol will be done ( q = - normal_q * factor + offset ) .
* - encoding : Set by user .
* - decoding : unused
*/
float i_quant_factor ;
/**
* qscale offset between P and I - frames
* - encoding : Set by user .
* - decoding : unused
*/
float i_quant_offset ;
/**
* luminance masking ( 0 - > disabled )
* - encoding : Set by user .
* - decoding : unused
*/
float lumi_masking ;
/**
* temporary complexity masking ( 0 - > disabled )
* - encoding : Set by user .
* - decoding : unused
*/
float temporal_cplx_masking ;
/**
* spatial complexity masking ( 0 - > disabled )
* - encoding : Set by user .
* - decoding : unused
*/
float spatial_cplx_masking ;
/**
* p block masking ( 0 - > disabled )
* - encoding : Set by user .
* - decoding : unused
*/
float p_masking ;
/**
* darkness masking ( 0 - > disabled )
* - encoding : Set by user .
* - decoding : unused
*/
float dark_masking ;
/**
* slice count
* - encoding : Set by libavcodec .
* - decoding : Set by user ( or 0 ) .
*/
int slice_count ;
/**
* slice offsets in the frame in bytes
* - encoding : Set / allocated by libavcodec .
* - decoding : Set / allocated by user ( or NULL ) .
*/
int * slice_offset ;
/**
* sample aspect ratio ( 0 if unknown )
* That is the width of a pixel divided by the height of the pixel .
* Numerator and denominator must be relatively prime and smaller than 256 for some video standards .
* - encoding : Set by user .
* - decoding : Set by libavcodec .
*/
AVRational sample_aspect_ratio ;
/**
* motion estimation comparison function
* - encoding : Set by user .
* - decoding : unused
*/
int me_cmp ;
/**
* subpixel motion estimation comparison function
* - encoding : Set by user .
* - decoding : unused
*/
int me_sub_cmp ;
/**
* macroblock comparison function ( not supported yet )
* - encoding : Set by user .
* - decoding : unused
*/
int mb_cmp ;
/**
* interlaced DCT comparison function
* - encoding : Set by user .
* - decoding : unused
*/
int ildct_cmp ;
# define FF_CMP_SAD 0
# define FF_CMP_SSE 1
# define FF_CMP_SATD 2
# define FF_CMP_DCT 3
# define FF_CMP_PSNR 4
# define FF_CMP_BIT 5
# define FF_CMP_RD 6
# define FF_CMP_ZERO 7
# define FF_CMP_VSAD 8
# define FF_CMP_VSSE 9
# define FF_CMP_NSSE 10
# define FF_CMP_W53 11
# define FF_CMP_W97 12
# define FF_CMP_DCTMAX 13
# define FF_CMP_DCT264 14
# define FF_CMP_MEDIAN_SAD 15
# define FF_CMP_CHROMA 256
/**
* ME diamond size & shape
* - encoding : Set by user .
* - decoding : unused
*/
int dia_size ;
/**
* amount of previous MV predictors ( 2 a + 1 x 2 a + 1 square )
* - encoding : Set by user .
* - decoding : unused
*/
int last_predictor_count ;
/**
* motion estimation prepass comparison function
* - encoding : Set by user .
* - decoding : unused
*/
int me_pre_cmp ;
/**
* ME prepass diamond size & shape
* - encoding : Set by user .
* - decoding : unused
*/
int pre_dia_size ;
/**
* subpel ME quality
* - encoding : Set by user .
* - decoding : unused
*/
int me_subpel_quality ;
/**
* maximum motion estimation search range in subpel units
* If 0 then no limit .
*
* - encoding : Set by user .
* - decoding : unused
*/
int me_range ;
/**
* slice flags
* - encoding : unused
* - decoding : Set by user .
*/
int slice_flags ;
# define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
# define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
# define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
/**
* macroblock decision mode
* - encoding : Set by user .
* - decoding : unused
*/
int mb_decision ;
# define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
# define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
# define FF_MB_DECISION_RD 2 ///< rate distortion
/**
* custom intra quantization matrix
* Must be allocated with the av_malloc ( ) family of functions , and will be freed in
* avcodec_free_context ( ) .
* - encoding : Set / allocated by user , freed by libavcodec . Can be NULL .
* - decoding : Set / allocated / freed by libavcodec .
*/
uint16_t * intra_matrix ;
/**
* custom inter quantization matrix
* Must be allocated with the av_malloc ( ) family of functions , and will be freed in
* avcodec_free_context ( ) .
* - encoding : Set / allocated by user , freed by libavcodec . Can be NULL .
* - decoding : Set / allocated / freed by libavcodec .
*/
uint16_t * inter_matrix ;
/**
* precision of the intra DC coefficient - 8
* - encoding : Set by user .
* - decoding : Set by libavcodec
*/
int intra_dc_precision ;
/**
* Number of macroblock rows at the top which are skipped .
* - encoding : unused
* - decoding : Set by user .
*/
int skip_top ;
/**
* Number of macroblock rows at the bottom which are skipped .
* - encoding : unused
* - decoding : Set by user .
*/
int skip_bottom ;
/**
* minimum MB Lagrange multiplier
* - encoding : Set by user .
* - decoding : unused
*/
int mb_lmin ;
/**
* maximum MB Lagrange multiplier
* - encoding : Set by user .
* - decoding : unused
*/
int mb_lmax ;
/**
* - encoding : Set by user .
* - decoding : unused
*/
int bidir_refine ;
/**
* minimum GOP size
* - encoding : Set by user .
* - decoding : unused
*/
int keyint_min ;
/**
* number of reference frames
* - encoding : Set by user .
* - decoding : Set by lavc .
*/
int refs ;
/**
* Note : Value depends upon the compare function used for fullpel ME .
* - encoding : Set by user .
* - decoding : unused
*/
int mv0_threshold ;
/**
* Chromaticity coordinates of the source primaries .
* - encoding : Set by user
* - decoding : Set by libavcodec
*/
enum AVColorPrimaries color_primaries ;
/**
* Color Transfer Characteristic .
* - encoding : Set by user
* - decoding : Set by libavcodec
*/
enum AVColorTransferCharacteristic color_trc ;
/**
* YUV colorspace type .
* - encoding : Set by user
* - decoding : Set by libavcodec
*/
enum AVColorSpace colorspace ;
/**
* MPEG vs JPEG YUV range .
* - encoding : Set by user
* - decoding : Set by libavcodec
*/
enum AVColorRange color_range ;
/**
* This defines the location of chroma samples .
* - encoding : Set by user
* - decoding : Set by libavcodec
*/
enum AVChromaLocation chroma_sample_location ;
/**
* Number of slices .
* Indicates number of picture subdivisions . Used for parallelized
* decoding .
* - encoding : Set by user
* - decoding : unused
*/
int slices ;
/** Field order
* - encoding : set by libavcodec
* - decoding : Set by user .
*/
enum AVFieldOrder field_order ;
/* audio only */
int sample_rate ; ///< samples per second
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# if FF_API_OLD_CHANNEL_LAYOUT
/**
* number of audio channels
* @ deprecated use ch_layout . nb_channels
*/
attribute_deprecated
int channels ;
# endif
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/**
* audio sample format
* - encoding : Set by user .
* - decoding : Set by libavcodec .
*/
enum AVSampleFormat sample_fmt ; ///< sample format
/* The following data should not be initialized. */
/**
* Number of samples per channel in an audio frame .
*
* - encoding : set by libavcodec in avcodec_open2 ( ) . Each submitted frame
* except the last must contain exactly frame_size samples per channel .
* May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set , then the
* frame size is not restricted .
* - decoding : may be set by some decoders to indicate constant frame size
*/
int frame_size ;
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# if FF_API_AVCTX_FRAME_NUMBER
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/**
* Frame counter , set by libavcodec .
*
* - decoding : total number of frames returned from the decoder so far .
* - encoding : total number of frames passed to the encoder so far .
*
* @ note the counter is not incremented if encoding / decoding resulted in
* an error .
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* @ deprecated use frame_num instead
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*/
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attribute_deprecated
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int frame_number ;
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# endif
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/**
* number of bytes per packet if constant and known or 0
* Used by some WAV based audio codecs .
*/
int block_align ;
/**
* Audio cutoff bandwidth ( 0 means " automatic " )
* - encoding : Set by user .
* - decoding : unused
*/
int cutoff ;
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# if FF_API_OLD_CHANNEL_LAYOUT
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/**
* Audio channel layout .
* - encoding : set by user .
* - decoding : set by user , may be overwritten by libavcodec .
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* @ deprecated use ch_layout
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*/
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attribute_deprecated
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uint64_t channel_layout ;
/**
* Request decoder to use this channel layout if it can ( 0 for default )
* - encoding : unused
* - decoding : Set by user .
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* @ deprecated use " downmix " codec private option
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*/
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attribute_deprecated
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uint64_t request_channel_layout ;
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# endif
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/**
* Type of service that the audio stream conveys .
* - encoding : Set by user .
* - decoding : Set by libavcodec .
*/
enum AVAudioServiceType audio_service_type ;
/**
* desired sample format
* - encoding : Not used .
* - decoding : Set by user .
* Decoder will decode to this format if it can .
*/
enum AVSampleFormat request_sample_fmt ;
/**
* This callback is called at the beginning of each frame to get data
* buffer ( s ) for it . There may be one contiguous buffer for all the data or
* there may be a buffer per each data plane or anything in between . What
* this means is , you may set however many entries in buf [ ] you feel necessary .
* Each buffer must be reference - counted using the AVBuffer API ( see description
* of buf [ ] below ) .
*
* The following fields will be set in the frame before this callback is
* called :
* - format
* - width , height ( video only )
* - sample_rate , channel_layout , nb_samples ( audio only )
* Their values may differ from the corresponding values in
* AVCodecContext . This callback must use the frame values , not the codec
* context values , to calculate the required buffer size .
*
* This callback must fill the following fields in the frame :
* - data [ ]
* - linesize [ ]
* - extended_data :
* * if the data is planar audio with more than 8 channels , then this
* callback must allocate and fill extended_data to contain all pointers
* to all data planes . data [ ] must hold as many pointers as it can .
* extended_data must be allocated with av_malloc ( ) and will be freed in
* av_frame_unref ( ) .
* * otherwise extended_data must point to data
* - buf [ ] must contain one or more pointers to AVBufferRef structures . Each of
* the frame ' s data and extended_data pointers must be contained in these . That
* is , one AVBufferRef for each allocated chunk of memory , not necessarily one
* AVBufferRef per data [ ] entry . See : av_buffer_create ( ) , av_buffer_alloc ( ) ,
* and av_buffer_ref ( ) .
* - extended_buf and nb_extended_buf must be allocated with av_malloc ( ) by
* this callback and filled with the extra buffers if there are more
* buffers than buf [ ] can hold . extended_buf will be freed in
* av_frame_unref ( ) .
*
* If AV_CODEC_CAP_DR1 is not set then get_buffer2 ( ) must call
* avcodec_default_get_buffer2 ( ) instead of providing buffers allocated by
* some other means .
*
* Each data plane must be aligned to the maximum required by the target
* CPU .
*
* @ see avcodec_default_get_buffer2 ( )
*
* Video :
*
* If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
* ( read and / or written to if it is writable ) later by libavcodec .
*
* avcodec_align_dimensions2 ( ) should be used to find the required width and
* height , as they normally need to be rounded up to the next multiple of 16.
*
* Some decoders do not support linesizes changing between frames .
*
* If frame multithreading is used , this callback may be called from a
* different thread , but not from more than one at once . Does not need to be
* reentrant .
*
* @ see avcodec_align_dimensions2 ( )
*
* Audio :
*
* Decoders request a buffer of a particular size by setting
* AVFrame . nb_samples prior to calling get_buffer2 ( ) . The decoder may ,
* however , utilize only part of the buffer by setting AVFrame . nb_samples
* to a smaller value in the output frame .
*
* As a convenience , av_samples_get_buffer_size ( ) and
* av_samples_fill_arrays ( ) in libavutil may be used by custom get_buffer2 ( )
* functions to find the required data size and to fill data pointers and
* linesize . In AVFrame . linesize , only linesize [ 0 ] may be set for audio
* since all planes must be the same size .
*
* @ see av_samples_get_buffer_size ( ) , av_samples_fill_arrays ( )
*
* - encoding : unused
* - decoding : Set by libavcodec , user can override .
*/
int ( * get_buffer2 ) ( struct AVCodecContext * s , AVFrame * frame , int flags ) ;
/* - encoding parameters */
float qcompress ; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
float qblur ; ///< amount of qscale smoothing over time (0.0-1.0)
/**
* minimum quantizer
* - encoding : Set by user .
* - decoding : unused
*/
int qmin ;
/**
* maximum quantizer
* - encoding : Set by user .
* - decoding : unused
*/
int qmax ;
/**
* maximum quantizer difference between frames
* - encoding : Set by user .
* - decoding : unused
*/
int max_qdiff ;
/**
* decoder bitstream buffer size
* - encoding : Set by user .
* - decoding : unused
*/
int rc_buffer_size ;
/**
* ratecontrol override , see RcOverride
* - encoding : Allocated / set / freed by user .
* - decoding : unused
*/
int rc_override_count ;
RcOverride * rc_override ;
/**
* maximum bitrate
* - encoding : Set by user .
* - decoding : Set by user , may be overwritten by libavcodec .
*/
int64_t rc_max_rate ;
/**
* minimum bitrate
* - encoding : Set by user .
* - decoding : unused
*/
int64_t rc_min_rate ;
/**
* Ratecontrol attempt to use , at maximum , < value > of what can be used without an underflow .
* - encoding : Set by user .
* - decoding : unused .
*/
float rc_max_available_vbv_use ;
/**
* Ratecontrol attempt to use , at least , < value > times the amount needed to prevent a vbv overflow .
* - encoding : Set by user .
* - decoding : unused .
*/
float rc_min_vbv_overflow_use ;
/**
* Number of bits which should be loaded into the rc buffer before decoding starts .
* - encoding : Set by user .
* - decoding : unused
*/
int rc_initial_buffer_occupancy ;
/**
* trellis RD quantization
* - encoding : Set by user .
* - decoding : unused
*/
int trellis ;
/**
* pass1 encoding statistics output buffer
* - encoding : Set by libavcodec .
* - decoding : unused
*/
char * stats_out ;
/**
* pass2 encoding statistics input buffer
* Concatenated stuff from stats_out of pass1 should be placed here .
* - encoding : Allocated / set / freed by user .
* - decoding : unused
*/
char * stats_in ;
/**
* Work around bugs in encoders which sometimes cannot be detected automatically .
* - encoding : Set by user
* - decoding : Set by user
*/
int workaround_bugs ;
# define FF_BUG_AUTODETECT 1 ///< autodetection
# define FF_BUG_XVID_ILACE 4
# define FF_BUG_UMP4 8
# define FF_BUG_NO_PADDING 16
# define FF_BUG_AMV 32
# define FF_BUG_QPEL_CHROMA 64
# define FF_BUG_STD_QPEL 128
# define FF_BUG_QPEL_CHROMA2 256
# define FF_BUG_DIRECT_BLOCKSIZE 512
# define FF_BUG_EDGE 1024
# define FF_BUG_HPEL_CHROMA 2048
# define FF_BUG_DC_CLIP 4096
# define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
# define FF_BUG_TRUNCATED 16384
# define FF_BUG_IEDGE 32768
/**
* strictly follow the standard ( MPEG - 4 , . . . ) .
* - encoding : Set by user .
* - decoding : Set by user .
* Setting this to STRICT or higher means the encoder and decoder will
* generally do stupid things , whereas setting it to unofficial or lower
* will mean the encoder might produce output that is not supported by all
* spec - compliant decoders . Decoders don ' t differentiate between normal ,
* unofficial and experimental ( that is , they always try to decode things
* when they can ) unless they are explicitly asked to behave stupidly
* ( = strictly conform to the specs )
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* This may only be set to one of the FF_COMPLIANCE_ * values in defs . h .
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*/
int strict_std_compliance ;
/**
* error concealment flags
* - encoding : unused
* - decoding : Set by user .
*/
int error_concealment ;
# define FF_EC_GUESS_MVS 1
# define FF_EC_DEBLOCK 2
# define FF_EC_FAVOR_INTER 256
/**
* debug
* - encoding : Set by user .
* - decoding : Set by user .
*/
int debug ;
# define FF_DEBUG_PICT_INFO 1
# define FF_DEBUG_RC 2
# define FF_DEBUG_BITSTREAM 4
# define FF_DEBUG_MB_TYPE 8
# define FF_DEBUG_QP 16
# define FF_DEBUG_DCT_COEFF 0x00000040
# define FF_DEBUG_SKIP 0x00000080
# define FF_DEBUG_STARTCODE 0x00000100
# define FF_DEBUG_ER 0x00000400
# define FF_DEBUG_MMCO 0x00000800
# define FF_DEBUG_BUGS 0x00001000
# define FF_DEBUG_BUFFERS 0x00008000
# define FF_DEBUG_THREADS 0x00010000
# define FF_DEBUG_GREEN_MD 0x00800000
# define FF_DEBUG_NOMC 0x01000000
/**
* Error recognition ; may misdetect some more or less valid parts as errors .
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* This is a bitfield of the AV_EF_ * values defined in defs . h .
*
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* - encoding : Set by user .
* - decoding : Set by user .
*/
int err_recognition ;
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# if FF_API_REORDERED_OPAQUE
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/**
* opaque 64 - bit number ( generally a PTS ) that will be reordered and
* output in AVFrame . reordered_opaque
* - encoding : Set by libavcodec to the reordered_opaque of the input
* frame corresponding to the last returned packet . Only
* supported by encoders with the
* AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability .
* - decoding : Set by user .
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*
* @ deprecated Use AV_CODEC_FLAG_COPY_OPAQUE instead
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*/
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attribute_deprecated
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int64_t reordered_opaque ;
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# endif
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/**
* Hardware accelerator in use
* - encoding : unused .
* - decoding : Set by libavcodec
*/
const struct AVHWAccel * hwaccel ;
/**
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* Legacy hardware accelerator context .
*
* For some hardware acceleration methods , the caller may use this field to
* signal hwaccel - specific data to the codec . The struct pointed to by this
* pointer is hwaccel - dependent and defined in the respective header . Please
* refer to the FFmpeg HW accelerator documentation to know how to fill
* this .
*
* In most cases this field is optional - the necessary information may also
* be provided to libavcodec through @ ref hw_frames_ctx or @ ref
* hw_device_ctx ( see avcodec_get_hw_config ( ) ) . However , in some cases it
* may be the only method of signalling some ( optional ) information .
*
* The struct and its contents are owned by the caller .
*
* - encoding : May be set by the caller before avcodec_open2 ( ) . Must remain
* valid until avcodec_free_context ( ) .
* - decoding : May be set by the caller in the get_format ( ) callback .
* Must remain valid until the next get_format ( ) call ,
* or avcodec_free_context ( ) ( whichever comes first ) .
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*/
void * hwaccel_context ;
/**
* error
* - encoding : Set by libavcodec if flags & AV_CODEC_FLAG_PSNR .
* - decoding : unused
*/
uint64_t error [ AV_NUM_DATA_POINTERS ] ;
/**
* DCT algorithm , see FF_DCT_ * below
* - encoding : Set by user .
* - decoding : unused
*/
int dct_algo ;
# define FF_DCT_AUTO 0
# define FF_DCT_FASTINT 1
# define FF_DCT_INT 2
# define FF_DCT_MMX 3
# define FF_DCT_ALTIVEC 5
# define FF_DCT_FAAN 6
/**
* IDCT algorithm , see FF_IDCT_ * below .
* - encoding : Set by user .
* - decoding : Set by user .
*/
int idct_algo ;
# define FF_IDCT_AUTO 0
# define FF_IDCT_INT 1
# define FF_IDCT_SIMPLE 2
# define FF_IDCT_SIMPLEMMX 3
# define FF_IDCT_ARM 7
# define FF_IDCT_ALTIVEC 8
# define FF_IDCT_SIMPLEARM 10
# define FF_IDCT_XVID 14
# define FF_IDCT_SIMPLEARMV5TE 16
# define FF_IDCT_SIMPLEARMV6 17
# define FF_IDCT_FAAN 20
# define FF_IDCT_SIMPLENEON 22
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# if FF_API_IDCT_NONE
// formerly used by xvmc
# define FF_IDCT_NONE 24
# endif
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# define FF_IDCT_SIMPLEAUTO 128
/**
* bits per sample / pixel from the demuxer ( needed for huffyuv ) .
* - encoding : Set by libavcodec .
* - decoding : Set by user .
*/
int bits_per_coded_sample ;
/**
* Bits per sample / pixel of internal libavcodec pixel / sample format .
* - encoding : set by user .
* - decoding : set by libavcodec .
*/
int bits_per_raw_sample ;
/**
* low resolution decoding , 1 - > 1 / 2 size , 2 - > 1 / 4 size
* - encoding : unused
* - decoding : Set by user .
*/
int lowres ;
/**
* thread count
* is used to decide how many independent tasks should be passed to execute ( )
* - encoding : Set by user .
* - decoding : Set by user .
*/
int thread_count ;
/**
* Which multithreading methods to use .
* Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread ,
* so clients which cannot provide future frames should not use it .
*
* - encoding : Set by user , otherwise the default is used .
* - decoding : Set by user , otherwise the default is used .
*/
int thread_type ;
# define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
# define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
/**
* Which multithreading methods are in use by the codec .
* - encoding : Set by libavcodec .
* - decoding : Set by libavcodec .
*/
int active_thread_type ;
/**
* The codec may call this to execute several independent things .
* It will return only after finishing all tasks .
* The user may replace this with some multithreaded implementation ,
* the default implementation will execute the parts serially .
* @ param count the number of things to execute
* - encoding : Set by libavcodec , user can override .
* - decoding : Set by libavcodec , user can override .
*/
int ( * execute ) ( struct AVCodecContext * c , int ( * func ) ( struct AVCodecContext * c2 , void * arg ) , void * arg2 , int * ret , int count , int size ) ;
/**
* The codec may call this to execute several independent things .
* It will return only after finishing all tasks .
* The user may replace this with some multithreaded implementation ,
* the default implementation will execute the parts serially .
* @ param c context passed also to func
* @ param count the number of things to execute
* @ param arg2 argument passed unchanged to func
* @ param ret return values of executed functions , must have space for " count " values . May be NULL .
* @ param func function that will be called count times , with jobnr from 0 to count - 1.
* threadnr will be in the range 0 to c - > thread_count - 1 < MAX_THREADS and so that no
* two instances of func executing at the same time will have the same threadnr .
* @ return always 0 currently , but code should handle a future improvement where when any call to func
* returns < 0 no further calls to func may be done and < 0 is returned .
* - encoding : Set by libavcodec , user can override .
* - decoding : Set by libavcodec , user can override .
*/
int ( * execute2 ) ( struct AVCodecContext * c , int ( * func ) ( struct AVCodecContext * c2 , void * arg , int jobnr , int threadnr ) , void * arg2 , int * ret , int count ) ;
/**
* noise vs . sse weight for the nsse comparison function
* - encoding : Set by user .
* - decoding : unused
*/
int nsse_weight ;
/**
* profile
* - encoding : Set by user .
* - decoding : Set by libavcodec .
*/
int profile ;
# define FF_PROFILE_UNKNOWN -99
# define FF_PROFILE_RESERVED -100
# define FF_PROFILE_AAC_MAIN 0
# define FF_PROFILE_AAC_LOW 1
# define FF_PROFILE_AAC_SSR 2
# define FF_PROFILE_AAC_LTP 3
# define FF_PROFILE_AAC_HE 4
# define FF_PROFILE_AAC_HE_V2 28
# define FF_PROFILE_AAC_LD 22
# define FF_PROFILE_AAC_ELD 38
# define FF_PROFILE_MPEG2_AAC_LOW 128
# define FF_PROFILE_MPEG2_AAC_HE 131
# define FF_PROFILE_DNXHD 0
# define FF_PROFILE_DNXHR_LB 1
# define FF_PROFILE_DNXHR_SQ 2
# define FF_PROFILE_DNXHR_HQ 3
# define FF_PROFILE_DNXHR_HQX 4
# define FF_PROFILE_DNXHR_444 5
# define FF_PROFILE_DTS 20
# define FF_PROFILE_DTS_ES 30
# define FF_PROFILE_DTS_96_24 40
# define FF_PROFILE_DTS_HD_HRA 50
# define FF_PROFILE_DTS_HD_MA 60
# define FF_PROFILE_DTS_EXPRESS 70
# define FF_PROFILE_MPEG2_422 0
# define FF_PROFILE_MPEG2_HIGH 1
# define FF_PROFILE_MPEG2_SS 2
# define FF_PROFILE_MPEG2_SNR_SCALABLE 3
# define FF_PROFILE_MPEG2_MAIN 4
# define FF_PROFILE_MPEG2_SIMPLE 5
# define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
# define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
# define FF_PROFILE_H264_BASELINE 66
# define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
# define FF_PROFILE_H264_MAIN 77
# define FF_PROFILE_H264_EXTENDED 88
# define FF_PROFILE_H264_HIGH 100
# define FF_PROFILE_H264_HIGH_10 110
# define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
# define FF_PROFILE_H264_MULTIVIEW_HIGH 118
# define FF_PROFILE_H264_HIGH_422 122
# define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
# define FF_PROFILE_H264_STEREO_HIGH 128
# define FF_PROFILE_H264_HIGH_444 144
# define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
# define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
# define FF_PROFILE_H264_CAVLC_444 44
# define FF_PROFILE_VC1_SIMPLE 0
# define FF_PROFILE_VC1_MAIN 1
# define FF_PROFILE_VC1_COMPLEX 2
# define FF_PROFILE_VC1_ADVANCED 3
# define FF_PROFILE_MPEG4_SIMPLE 0
# define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
# define FF_PROFILE_MPEG4_CORE 2
# define FF_PROFILE_MPEG4_MAIN 3
# define FF_PROFILE_MPEG4_N_BIT 4
# define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
# define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
# define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
# define FF_PROFILE_MPEG4_HYBRID 8
# define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
# define FF_PROFILE_MPEG4_CORE_SCALABLE 10
# define FF_PROFILE_MPEG4_ADVANCED_CODING 11
# define FF_PROFILE_MPEG4_ADVANCED_CORE 12
# define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
# define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
# define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
# define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
# define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
# define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
# define FF_PROFILE_JPEG2000_DCINEMA_2K 3
# define FF_PROFILE_JPEG2000_DCINEMA_4K 4
# define FF_PROFILE_VP9_0 0
# define FF_PROFILE_VP9_1 1
# define FF_PROFILE_VP9_2 2
# define FF_PROFILE_VP9_3 3
# define FF_PROFILE_HEVC_MAIN 1
# define FF_PROFILE_HEVC_MAIN_10 2
# define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
# define FF_PROFILE_HEVC_REXT 4
# define FF_PROFILE_VVC_MAIN_10 1
# define FF_PROFILE_VVC_MAIN_10_444 33
# define FF_PROFILE_AV1_MAIN 0
# define FF_PROFILE_AV1_HIGH 1
# define FF_PROFILE_AV1_PROFESSIONAL 2
# define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
# define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
# define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
# define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
# define FF_PROFILE_MJPEG_JPEG_LS 0xf7
# define FF_PROFILE_SBC_MSBC 1
# define FF_PROFILE_PRORES_PROXY 0
# define FF_PROFILE_PRORES_LT 1
# define FF_PROFILE_PRORES_STANDARD 2
# define FF_PROFILE_PRORES_HQ 3
# define FF_PROFILE_PRORES_4444 4
# define FF_PROFILE_PRORES_XQ 5
# define FF_PROFILE_ARIB_PROFILE_A 0
# define FF_PROFILE_ARIB_PROFILE_C 1
# define FF_PROFILE_KLVA_SYNC 0
# define FF_PROFILE_KLVA_ASYNC 1
/**
* level
* - encoding : Set by user .
* - decoding : Set by libavcodec .
*/
int level ;
# define FF_LEVEL_UNKNOWN -99
/**
* Skip loop filtering for selected frames .
* - encoding : unused
* - decoding : Set by user .
*/
enum AVDiscard skip_loop_filter ;
/**
* Skip IDCT / dequantization for selected frames .
* - encoding : unused
* - decoding : Set by user .
*/
enum AVDiscard skip_idct ;
/**
* Skip decoding for selected frames .
* - encoding : unused
* - decoding : Set by user .
*/
enum AVDiscard skip_frame ;
/**
* Header containing style information for text subtitles .
* For SUBTITLE_ASS subtitle type , it should contain the whole ASS
* [ Script Info ] and [ V4 + Styles ] section , plus the [ Events ] line and
* the Format line following . It shouldn ' t include any Dialogue line .
* - encoding : Set / allocated / freed by user ( before avcodec_open2 ( ) )
* - decoding : Set / allocated / freed by libavcodec ( by avcodec_open2 ( ) )
*/
uint8_t * subtitle_header ;
int subtitle_header_size ;
/**
* Audio only . The number of " priming " samples ( padding ) inserted by the
* encoder at the beginning of the audio . I . e . this number of leading
* decoded samples must be discarded by the caller to get the original audio
* without leading padding .
*
* - decoding : unused
* - encoding : Set by libavcodec . The timestamps on the output packets are
* adjusted by the encoder so that they always refer to the
* first sample of the data actually contained in the packet ,
* including any added padding . E . g . if the timebase is
* 1 / samplerate and the timestamp of the first input sample is
* 0 , the timestamp of the first output packet will be
* - initial_padding .
*/
int initial_padding ;
/**
* - decoding : For codecs that store a framerate value in the compressed
* bitstream , the decoder may export it here . { 0 , 1 } when
* unknown .
* - encoding : May be used to signal the framerate of CFR content to an
* encoder .
*/
AVRational framerate ;
/**
* Nominal unaccelerated pixel format , see AV_PIX_FMT_xxx .
* - encoding : unused .
* - decoding : Set by libavcodec before calling get_format ( )
*/
enum AVPixelFormat sw_pix_fmt ;
/**
* Timebase in which pkt_dts / pts and AVPacket . dts / pts are .
* - encoding unused .
* - decoding set by user .
*/
AVRational pkt_timebase ;
/**
* AVCodecDescriptor
* - encoding : unused .
* - decoding : set by libavcodec .
*/
const AVCodecDescriptor * codec_descriptor ;
/**
* Current statistics for PTS correction .
* - decoding : maintained and used by libavcodec , not intended to be used by user apps
* - encoding : unused
*/
int64_t pts_correction_num_faulty_pts ; /// Number of incorrect PTS values so far
int64_t pts_correction_num_faulty_dts ; /// Number of incorrect DTS values so far
int64_t pts_correction_last_pts ; /// PTS of the last frame
int64_t pts_correction_last_dts ; /// DTS of the last frame
/**
* Character encoding of the input subtitles file .
* - decoding : set by user
* - encoding : unused
*/
char * sub_charenc ;
/**
* Subtitles character encoding mode . Formats or codecs might be adjusting
* this setting ( if they are doing the conversion themselves for instance ) .
* - decoding : set by libavcodec
* - encoding : unused
*/
int sub_charenc_mode ;
# define FF_SUB_CHARENC_MODE_DO_NOTHING -1 ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
# define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
# define FF_SUB_CHARENC_MODE_PRE_DECODER 1 ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
# define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
/**
* Skip processing alpha if supported by codec .
* Note that if the format uses pre - multiplied alpha ( common with VP6 ,
* and recommended due to better video quality / compression )
* the image will look as if alpha - blended onto a black background .
* However for formats that do not use pre - multiplied alpha
* there might be serious artefacts ( though e . g . libswscale currently
* assumes pre - multiplied alpha anyway ) .
*
* - decoding : set by user
* - encoding : unused
*/
int skip_alpha ;
/**
* Number of samples to skip after a discontinuity
* - decoding : unused
* - encoding : set by libavcodec
*/
int seek_preroll ;
/**
* custom intra quantization matrix
* - encoding : Set by user , can be NULL .
* - decoding : unused .
*/
uint16_t * chroma_intra_matrix ;
/**
* dump format separator .
* can be " , " or " \n " or anything else
* - encoding : Set by user .
* - decoding : Set by user .
*/
uint8_t * dump_separator ;
/**
* ' , ' separated list of allowed decoders .
* If NULL then all are allowed
* - encoding : unused
* - decoding : set by user
*/
char * codec_whitelist ;
/**
* Properties of the stream that gets decoded
* - encoding : unused
* - decoding : set by libavcodec
*/
unsigned properties ;
# define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
# define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
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# define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
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/**
* Additional data associated with the entire coded stream .
*
* - decoding : unused
* - encoding : may be set by libavcodec after avcodec_open2 ( ) .
*/
AVPacketSideData * coded_side_data ;
int nb_coded_side_data ;
/**
* A reference to the AVHWFramesContext describing the input ( for encoding )
* or output ( decoding ) frames . The reference is set by the caller and
* afterwards owned ( and freed ) by libavcodec - it should never be read by
* the caller after being set .
*
* - decoding : This field should be set by the caller from the get_format ( )
* callback . The previous reference ( if any ) will always be
* unreffed by libavcodec before the get_format ( ) call .
*
* If the default get_buffer2 ( ) is used with a hwaccel pixel
* format , then this AVHWFramesContext will be used for
* allocating the frame buffers .
*
* - encoding : For hardware encoders configured to use a hwaccel pixel
* format , this field should be set by the caller to a reference
* to the AVHWFramesContext describing input frames .
* AVHWFramesContext . format must be equal to
* AVCodecContext . pix_fmt .
*
* This field should be set before avcodec_open2 ( ) is called .
*/
AVBufferRef * hw_frames_ctx ;
/**
* Audio only . The amount of padding ( in samples ) appended by the encoder to
* the end of the audio . I . e . this number of decoded samples must be
* discarded by the caller from the end of the stream to get the original
* audio without any trailing padding .
*
* - decoding : unused
* - encoding : unused
*/
int trailing_padding ;
/**
* The number of pixels per image to maximally accept .
*
* - decoding : set by user
* - encoding : set by user
*/
int64_t max_pixels ;
/**
* A reference to the AVHWDeviceContext describing the device which will
* be used by a hardware encoder / decoder . The reference is set by the
* caller and afterwards owned ( and freed ) by libavcodec .
*
* This should be used if either the codec device does not require
* hardware frames or any that are used are to be allocated internally by
* libavcodec . If the user wishes to supply any of the frames used as
* encoder input or decoder output then hw_frames_ctx should be used
* instead . When hw_frames_ctx is set in get_format ( ) for a decoder , this
* field will be ignored while decoding the associated stream segment , but
* may again be used on a following one after another get_format ( ) call .
*
* For both encoders and decoders this field should be set before
* avcodec_open2 ( ) is called and must not be written to thereafter .
*
* Note that some decoders may require this field to be set initially in
* order to support hw_frames_ctx at all - in that case , all frames
* contexts used must be created on the same device .
*/
AVBufferRef * hw_device_ctx ;
/**
* Bit set of AV_HWACCEL_FLAG_ * flags , which affect hardware accelerated
* decoding ( if active ) .
* - encoding : unused
* - decoding : Set by user ( either before avcodec_open2 ( ) , or in the
* AVCodecContext . get_format callback )
*/
int hwaccel_flags ;
/**
* Video decoding only . Certain video codecs support cropping , meaning that
* only a sub - rectangle of the decoded frame is intended for display . This
* option controls how cropping is handled by libavcodec .
*
* When set to 1 ( the default ) , libavcodec will apply cropping internally .
* I . e . it will modify the output frame width / height fields and offset the
* data pointers ( only by as much as possible while preserving alignment , or
* by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set ) so that
* the frames output by the decoder refer only to the cropped area . The
* crop_ * fields of the output frames will be zero .
*
* When set to 0 , the width / height fields of the output frames will be set
* to the coded dimensions and the crop_ * fields will describe the cropping
* rectangle . Applying the cropping is left to the caller .
*
* @ warning When hardware acceleration with opaque output frames is used ,
* libavcodec is unable to apply cropping from the top / left border .
*
* @ note when this option is set to zero , the width / height fields of the
* AVCodecContext and output AVFrames have different meanings . The codec
* context fields store display dimensions ( with the coded dimensions in
* coded_width / height ) , while the frame fields store the coded dimensions
* ( with the display dimensions being determined by the crop_ * fields ) .
*/
int apply_cropping ;
/*
* Video decoding only . Sets the number of extra hardware frames which
* the decoder will allocate for use by the caller . This must be set
* before avcodec_open2 ( ) is called .
*
* Some hardware decoders require all frames that they will use for
* output to be defined in advance before decoding starts . For such
* decoders , the hardware frame pool must therefore be of a fixed size .
* The extra frames set here are on top of any number that the decoder
* needs internally in order to operate normally ( for example , frames
* used as reference pictures ) .
*/
int extra_hw_frames ;
/**
* The percentage of damaged samples to discard a frame .
*
* - decoding : set by user
* - encoding : unused
*/
int discard_damaged_percentage ;
/**
* The number of samples per frame to maximally accept .
*
* - decoding : set by user
* - encoding : set by user
*/
int64_t max_samples ;
/**
* Bit set of AV_CODEC_EXPORT_DATA_ * flags , which affects the kind of
* metadata exported in frame , packet , or coded stream side data by
* decoders and encoders .
*
* - decoding : set by user
* - encoding : set by user
*/
int export_side_data ;
/**
* This callback is called at the beginning of each packet to get a data
* buffer for it .
*
* The following field will be set in the packet before this callback is
* called :
* - size
* This callback must use the above value to calculate the required buffer size ,
* which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes .
*
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* In some specific cases , the encoder may not use the entire buffer allocated by this
* callback . This will be reflected in the size value in the packet once returned by
* avcodec_receive_packet ( ) .
*
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* This callback must fill the following fields in the packet :
* - data : alignment requirements for AVPacket apply , if any . Some architectures and
* encoders may benefit from having aligned data .
* - buf : must contain a pointer to an AVBufferRef structure . The packet ' s
* data pointer must be contained in it . See : av_buffer_create ( ) , av_buffer_alloc ( ) ,
* and av_buffer_ref ( ) .
*
* If AV_CODEC_CAP_DR1 is not set then get_encode_buffer ( ) must call
* avcodec_default_get_encode_buffer ( ) instead of providing a buffer allocated by
* some other means .
*
* The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags .
* They may be used for example to hint what use the buffer may get after being
* created .
* Implementations of this callback may ignore flags they don ' t understand .
* If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
* ( read and / or written to if it is writable ) later by libavcodec .
*
* This callback must be thread - safe , as when frame threading is used , it may
* be called from multiple threads simultaneously .
*
* @ see avcodec_default_get_encode_buffer ( )
*
* - encoding : Set by libavcodec , user can override .
* - decoding : unused
*/
int ( * get_encode_buffer ) ( struct AVCodecContext * s , AVPacket * pkt , int flags ) ;
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/**
* Audio channel layout .
* - encoding : must be set by the caller , to one of AVCodec . ch_layouts .
* - decoding : may be set by the caller if known e . g . from the container .
* The decoder can then override during decoding as needed .
*/
AVChannelLayout ch_layout ;
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/**
* Frame counter , set by libavcodec .
*
* - decoding : total number of frames returned from the decoder so far .
* - encoding : total number of frames passed to the encoder so far .
*
* @ note the counter is not incremented if encoding / decoding resulted in
* an error .
*/
int64_t frame_num ;
} AVCodecContext ;
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/**
* @ defgroup lavc_hwaccel AVHWAccel
*
* @ note Nothing in this structure should be accessed by the user . At some
* point in future it will not be externally visible at all .
*
* @ {
*/
typedef struct AVHWAccel {
/**
* Name of the hardware accelerated codec .
* The name is globally unique among encoders and among decoders ( but an
* encoder and a decoder can share the same name ) .
*/
const char * name ;
/**
* Type of codec implemented by the hardware accelerator .
*
* See AVMEDIA_TYPE_xxx
*/
enum AVMediaType type ;
/**
* Codec implemented by the hardware accelerator .
*
* See AV_CODEC_ID_xxx
*/
enum AVCodecID id ;
/**
* Supported pixel format .
*
* Only hardware accelerated formats are supported here .
*/
enum AVPixelFormat pix_fmt ;
/**
* Hardware accelerated codec capabilities .
* see AV_HWACCEL_CODEC_CAP_ *
*/
int capabilities ;
/*****************************************************************
* No fields below this line are part of the public API . They
* may not be used outside of libavcodec and can be changed and
* removed at will .
* New public fields should be added right above .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*/
/**
* Allocate a custom buffer
*/
int ( * alloc_frame ) ( AVCodecContext * avctx , AVFrame * frame ) ;
/**
* Called at the beginning of each frame or field picture .
*
* Meaningful frame information ( codec specific ) is guaranteed to
* be parsed at this point . This function is mandatory .
*
* Note that buf can be NULL along with buf_size set to 0.
* Otherwise , this means the whole frame is available at this point .
*
* @ param avctx the codec context
* @ param buf the frame data buffer base
* @ param buf_size the size of the frame in bytes
* @ return zero if successful , a negative value otherwise
*/
int ( * start_frame ) ( AVCodecContext * avctx , const uint8_t * buf , uint32_t buf_size ) ;
/**
* Callback for parameter data ( SPS / PPS / VPS etc ) .
*
* Useful for hardware decoders which keep persistent state about the
* video parameters , and need to receive any changes to update that state .
*
* @ param avctx the codec context
* @ param type the nal unit type
* @ param buf the nal unit data buffer
* @ param buf_size the size of the nal unit in bytes
* @ return zero if successful , a negative value otherwise
*/
int ( * decode_params ) ( AVCodecContext * avctx , int type , const uint8_t * buf , uint32_t buf_size ) ;
/**
* Callback for each slice .
*
* Meaningful slice information ( codec specific ) is guaranteed to
* be parsed at this point . This function is mandatory .
*
* @ param avctx the codec context
* @ param buf the slice data buffer base
* @ param buf_size the size of the slice in bytes
* @ return zero if successful , a negative value otherwise
*/
int ( * decode_slice ) ( AVCodecContext * avctx , const uint8_t * buf , uint32_t buf_size ) ;
/**
* Called at the end of each frame or field picture .
*
* The whole picture is parsed at this point and can now be sent
* to the hardware accelerator . This function is mandatory .
*
* @ param avctx the codec context
* @ return zero if successful , a negative value otherwise
*/
int ( * end_frame ) ( AVCodecContext * avctx ) ;
/**
* Size of per - frame hardware accelerator private data .
*
* Private data is allocated with av_mallocz ( ) before
* AVCodecContext . get_buffer ( ) and deallocated after
* AVCodecContext . release_buffer ( ) .
*/
int frame_priv_data_size ;
/**
* Initialize the hwaccel private data .
*
* This will be called from ff_get_format ( ) , after hwaccel and
* hwaccel_context are set and the hwaccel private data in AVCodecInternal
* is allocated .
*/
int ( * init ) ( AVCodecContext * avctx ) ;
/**
* Uninitialize the hwaccel private data .
*
* This will be called from get_format ( ) or avcodec_close ( ) , after hwaccel
* and hwaccel_context are already uninitialized .
*/
int ( * uninit ) ( AVCodecContext * avctx ) ;
/**
* Size of the private data to allocate in
* AVCodecInternal . hwaccel_priv_data .
*/
int priv_data_size ;
/**
* Internal hwaccel capabilities .
*/
int caps_internal ;
/**
* Fill the given hw_frames context with current codec parameters . Called
* from get_format . Refer to avcodec_get_hw_frames_parameters ( ) for
* details .
*
* This CAN be called before AVHWAccel . init is called , and you must assume
* that avctx - > hwaccel_priv_data is invalid .
*/
int ( * frame_params ) ( AVCodecContext * avctx , AVBufferRef * hw_frames_ctx ) ;
} AVHWAccel ;
/**
* HWAccel is experimental and is thus avoided in favor of non experimental
* codecs
*/
# define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
/**
* Hardware acceleration should be used for decoding even if the codec level
* used is unknown or higher than the maximum supported level reported by the
* hardware driver .
*
* It ' s generally a good idea to pass this flag unless you have a specific
* reason not to , as hardware tends to under - report supported levels .
*/
# define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
/**
* Hardware acceleration can output YUV pixel formats with a different chroma
* sampling than 4 : 2 : 0 and / or other than 8 bits per component .
*/
# define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
/**
* Hardware acceleration should still be attempted for decoding when the
* codec profile does not match the reported capabilities of the hardware .
*
* For example , this can be used to try to decode baseline profile H .264
* streams in hardware - it will often succeed , because many streams marked
* as baseline profile actually conform to constrained baseline profile .
*
* @ warning If the stream is actually not supported then the behaviour is
* undefined , and may include returning entirely incorrect output
* while indicating success .
*/
# define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
/**
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* Some hardware decoders ( namely nvdec ) can either output direct decoder
* surfaces , or make an on - device copy and return said copy .
* There is a hard limit on how many decoder surfaces there can be , and it
* cannot be accurately guessed ahead of time .
* For some processing chains , this can be okay , but others will run into the
* limit and in turn produce very confusing errors that require fine tuning of
* more or less obscure options by the user , or in extreme cases cannot be
* resolved at all without inserting an avfilter that forces a copy .
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*
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* Thus , the hwaccel will by default make a copy for safety and resilience .
* If a users really wants to minimize the amount of copies , they can set this
* flag and ensure their processing chain does not exhaust the surface pool .
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*/
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# define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
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/**
* @ }
*/
enum AVSubtitleType {
SUBTITLE_NONE ,
SUBTITLE_BITMAP , ///< A bitmap, pict will be set
/**
* Plain text , the text field must be set by the decoder and is
* authoritative . ass and pict fields may contain approximations .
*/
SUBTITLE_TEXT ,
/**
* Formatted text , the ass field must be set by the decoder and is
* authoritative . pict and text fields may contain approximations .
*/
SUBTITLE_ASS ,
} ;
# define AV_SUBTITLE_FLAG_FORCED 0x00000001
typedef struct AVSubtitleRect {
int x ; ///< top left corner of pict, undefined when pict is not set
int y ; ///< top left corner of pict, undefined when pict is not set
int w ; ///< width of pict, undefined when pict is not set
int h ; ///< height of pict, undefined when pict is not set
int nb_colors ; ///< number of colors in pict, undefined when pict is not set
/**
* data + linesize for the bitmap of this subtitle .
* Can be set for text / ass as well once they are rendered .
*/
uint8_t * data [ 4 ] ;
int linesize [ 4 ] ;
enum AVSubtitleType type ;
char * text ; ///< 0 terminated plain UTF-8 text
/**
* 0 terminated ASS / SSA compatible event line .
* The presentation of this is unaffected by the other values in this
* struct .
*/
char * ass ;
int flags ;
} AVSubtitleRect ;
typedef struct AVSubtitle {
uint16_t format ; /* 0 = graphics */
uint32_t start_display_time ; /* relative to packet pts, in ms */
uint32_t end_display_time ; /* relative to packet pts, in ms */
unsigned num_rects ;
AVSubtitleRect * * rects ;
int64_t pts ; ///< Same as packet pts, in AV_TIME_BASE
} AVSubtitle ;
/**
* Return the LIBAVCODEC_VERSION_INT constant .
*/
unsigned avcodec_version ( void ) ;
/**
* Return the libavcodec build - time configuration .
*/
const char * avcodec_configuration ( void ) ;
/**
* Return the libavcodec license .
*/
const char * avcodec_license ( void ) ;
/**
* Allocate an AVCodecContext and set its fields to default values . The
* resulting struct should be freed with avcodec_free_context ( ) .
*
* @ param codec if non - NULL , allocate private data and initialize defaults
* for the given codec . It is illegal to then call avcodec_open2 ( )
* with a different codec .
* If NULL , then the codec - specific defaults won ' t be initialized ,
* which may result in suboptimal default settings ( this is
* important mainly for encoders , e . g . libx264 ) .
*
* @ return An AVCodecContext filled with default values or NULL on failure .
*/
AVCodecContext * avcodec_alloc_context3 ( const AVCodec * codec ) ;
/**
* Free the codec context and everything associated with it and write NULL to
* the provided pointer .
*/
void avcodec_free_context ( AVCodecContext * * avctx ) ;
/**
* Get the AVClass for AVCodecContext . It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options .
*
* @ see av_opt_find ( ) .
*/
const AVClass * avcodec_get_class ( void ) ;
/**
* Get the AVClass for AVSubtitleRect . It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options .
*
* @ see av_opt_find ( ) .
*/
const AVClass * avcodec_get_subtitle_rect_class ( void ) ;
/**
* Fill the parameters struct based on the values from the supplied codec
* context . Any allocated fields in par are freed and replaced with duplicates
* of the corresponding fields in codec .
*
* @ return > = 0 on success , a negative AVERROR code on failure
*/
int avcodec_parameters_from_context ( AVCodecParameters * par ,
const AVCodecContext * codec ) ;
/**
* Fill the codec context based on the values from the supplied codec
* parameters . Any allocated fields in codec that have a corresponding field in
* par are freed and replaced with duplicates of the corresponding field in par .
* Fields in codec that do not have a counterpart in par are not touched .
*
* @ return > = 0 on success , a negative AVERROR code on failure .
*/
int avcodec_parameters_to_context ( AVCodecContext * codec ,
const AVCodecParameters * par ) ;
/**
* Initialize the AVCodecContext to use the given AVCodec . Prior to using this
* function the context has to be allocated with avcodec_alloc_context3 ( ) .
*
* The functions avcodec_find_decoder_by_name ( ) , avcodec_find_encoder_by_name ( ) ,
* avcodec_find_decoder ( ) and avcodec_find_encoder ( ) provide an easy way for
* retrieving a codec .
*
* @ note Always call this function before using decoding routines ( such as
* @ ref avcodec_receive_frame ( ) ) .
*
* @ code
* av_dict_set ( & opts , " b " , " 2.5M " , 0 ) ;
* codec = avcodec_find_decoder ( AV_CODEC_ID_H264 ) ;
* if ( ! codec )
* exit ( 1 ) ;
*
* context = avcodec_alloc_context3 ( codec ) ;
*
* if ( avcodec_open2 ( context , codec , opts ) < 0 )
* exit ( 1 ) ;
* @ endcode
*
* @ param avctx The context to initialize .
* @ param codec The codec to open this context for . If a non - NULL codec has been
* previously passed to avcodec_alloc_context3 ( ) or
* for this context , then this parameter MUST be either NULL or
* equal to the previously passed codec .
* @ param options A dictionary filled with AVCodecContext and codec - private options .
* On return this object will be filled with options that were not found .
*
* @ return zero on success , a negative value on error
* @ see avcodec_alloc_context3 ( ) , avcodec_find_decoder ( ) , avcodec_find_encoder ( ) ,
* av_dict_set ( ) , av_opt_find ( ) .
*/
int avcodec_open2 ( AVCodecContext * avctx , const AVCodec * codec , AVDictionary * * options ) ;
/**
* Close a given AVCodecContext and free all the data associated with it
* ( but not the AVCodecContext itself ) .
*
* Calling this function on an AVCodecContext that hasn ' t been opened will free
* the codec - specific data allocated in avcodec_alloc_context3 ( ) with a non - NULL
* codec . Subsequent calls will do nothing .
*
* @ note Do not use this function . Use avcodec_free_context ( ) to destroy a
* codec context ( either open or closed ) . Opening and closing a codec context
* multiple times is not supported anymore - - use multiple codec contexts
* instead .
*/
int avcodec_close ( AVCodecContext * avctx ) ;
/**
* Free all allocated data in the given subtitle struct .
*
* @ param sub AVSubtitle to free .
*/
void avsubtitle_free ( AVSubtitle * sub ) ;
/**
* @ }
*/
/**
* @ addtogroup lavc_decoding
* @ {
*/
/**
* The default callback for AVCodecContext . get_buffer2 ( ) . It is made public so
* it can be called by custom get_buffer2 ( ) implementations for decoders without
* AV_CODEC_CAP_DR1 set .
*/
int avcodec_default_get_buffer2 ( AVCodecContext * s , AVFrame * frame , int flags ) ;
/**
* The default callback for AVCodecContext . get_encode_buffer ( ) . It is made public so
* it can be called by custom get_encode_buffer ( ) implementations for encoders without
* AV_CODEC_CAP_DR1 set .
*/
int avcodec_default_get_encode_buffer ( AVCodecContext * s , AVPacket * pkt , int flags ) ;
/**
* Modify width and height values so that they will result in a memory
* buffer that is acceptable for the codec if you do not use any horizontal
* padding .
*
* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened .
*/
void avcodec_align_dimensions ( AVCodecContext * s , int * width , int * height ) ;
/**
* Modify width and height values so that they will result in a memory
* buffer that is acceptable for the codec if you also ensure that all
* line sizes are a multiple of the respective linesize_align [ i ] .
*
* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened .
*/
void avcodec_align_dimensions2 ( AVCodecContext * s , int * width , int * height ,
int linesize_align [ AV_NUM_DATA_POINTERS ] ) ;
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# ifdef FF_API_AVCODEC_CHROMA_POS
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/**
* Converts AVChromaLocation to swscale x / y chroma position .
*
* The positions represent the chroma ( 0 , 0 ) position in a coordinates system
* with luma ( 0 , 0 ) representing the origin and luma ( 1 , 1 ) representing 256 , 256
*
* @ param xpos horizontal chroma sample position
* @ param ypos vertical chroma sample position
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* @ deprecated Use av_chroma_location_enum_to_pos ( ) instead .
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*/
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attribute_deprecated
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int avcodec_enum_to_chroma_pos ( int * xpos , int * ypos , enum AVChromaLocation pos ) ;
/**
* Converts swscale x / y chroma position to AVChromaLocation .
*
* The positions represent the chroma ( 0 , 0 ) position in a coordinates system
* with luma ( 0 , 0 ) representing the origin and luma ( 1 , 1 ) representing 256 , 256
*
* @ param xpos horizontal chroma sample position
* @ param ypos vertical chroma sample position
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* @ deprecated Use av_chroma_location_pos_to_enum ( ) instead .
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*/
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attribute_deprecated
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enum AVChromaLocation avcodec_chroma_pos_to_enum ( int xpos , int ypos ) ;
# endif
/**
* Decode a subtitle message .
* Return a negative value on error , otherwise return the number of bytes used .
* If no subtitle could be decompressed , got_sub_ptr is zero .
* Otherwise , the subtitle is stored in * sub .
* Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs . This is for
* simplicity , because the performance difference is expected to be negligible
* and reusing a get_buffer written for video codecs would probably perform badly
* due to a potentially very different allocation pattern .
*
* Some decoders ( those marked with AV_CODEC_CAP_DELAY ) have a delay between input
* and output . This means that for some packets they will not immediately
* produce decoded output and need to be flushed at the end of decoding to get
* all the decoded data . Flushing is done by calling this function with packets
* with avpkt - > data set to NULL and avpkt - > size set to 0 until it stops
* returning subtitles . It is safe to flush even those decoders that are not
* marked with AV_CODEC_CAP_DELAY , then no subtitles will be returned .
*
* @ note The AVCodecContext MUST have been opened with @ ref avcodec_open2 ( )
* before packets may be fed to the decoder .
*
* @ param avctx the codec context
* @ param [ out ] sub The preallocated AVSubtitle in which the decoded subtitle will be stored ,
* must be freed with avsubtitle_free if * got_sub_ptr is set .
* @ param [ in , out ] got_sub_ptr Zero if no subtitle could be decompressed , otherwise , it is nonzero .
* @ param [ in ] avpkt The input AVPacket containing the input buffer .
*/
int avcodec_decode_subtitle2 ( AVCodecContext * avctx , AVSubtitle * sub ,
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int * got_sub_ptr , const AVPacket * avpkt ) ;
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/**
* Supply raw packet data as input to a decoder .
*
* Internally , this call will copy relevant AVCodecContext fields , which can
* influence decoding per - packet , and apply them when the packet is actually
* decoded . ( For example AVCodecContext . skip_frame , which might direct the
* decoder to drop the frame contained by the packet sent with this function . )
*
* @ warning The input buffer , avpkt - > data must be AV_INPUT_BUFFER_PADDING_SIZE
* larger than the actual read bytes because some optimized bitstream
* readers read 32 or 64 bits at once and could read over the end .
*
* @ note The AVCodecContext MUST have been opened with @ ref avcodec_open2 ( )
* before packets may be fed to the decoder .
*
* @ param avctx codec context
* @ param [ in ] avpkt The input AVPacket . Usually , this will be a single video
* frame , or several complete audio frames .
* Ownership of the packet remains with the caller , and the
* decoder will not write to the packet . The decoder may create
* a reference to the packet data ( or copy it if the packet is
* not reference - counted ) .
* Unlike with older APIs , the packet is always fully consumed ,
* and if it contains multiple frames ( e . g . some audio codecs ) ,
* will require you to call avcodec_receive_frame ( ) multiple
* times afterwards before you can send a new packet .
* It can be NULL ( or an AVPacket with data set to NULL and
* size set to 0 ) ; in this case , it is considered a flush
* packet , which signals the end of the stream . Sending the
* first flush packet will return success . Subsequent ones are
* unnecessary and will return AVERROR_EOF . If the decoder
* still has frames buffered , it will return them after sending
* a flush packet .
*
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* @ retval 0 success
* @ retval AVERROR ( EAGAIN ) input is not accepted in the current state - user
* must read output with avcodec_receive_frame ( ) ( once
* all output is read , the packet should be resent ,
* and the call will not fail with EAGAIN ) .
* @ retval AVERROR_EOF the decoder has been flushed , and no new packets can be
* sent to it ( also returned if more than 1 flush
* packet is sent )
* @ retval AVERROR ( EINVAL ) codec not opened , it is an encoder , or requires flush
* @ retval AVERROR ( ENOMEM ) failed to add packet to internal queue , or similar
* @ retval " another negative error code " legitimate decoding errors
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*/
int avcodec_send_packet ( AVCodecContext * avctx , const AVPacket * avpkt ) ;
/**
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* Return decoded output data from a decoder or encoder ( when the
* AV_CODEC_FLAG_RECON_FRAME flag is used ) .
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*
* @ param avctx codec context
* @ param frame This will be set to a reference - counted video or audio
* frame ( depending on the decoder type ) allocated by the
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* codec . Note that the function will always call
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* av_frame_unref ( frame ) before doing anything else .
*
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* @ retval 0 success , a frame was returned
* @ retval AVERROR ( EAGAIN ) output is not available in this state - user must
* try to send new input
* @ retval AVERROR_EOF the codec has been fully flushed , and there will be
* no more output frames
* @ retval AVERROR ( EINVAL ) codec not opened , or it is an encoder without the
* AV_CODEC_FLAG_RECON_FRAME flag enabled
* @ retval AVERROR_INPUT_CHANGED current decoded frame has changed parameters with
* respect to first decoded frame . Applicable when flag
* AV_CODEC_FLAG_DROPCHANGED is set .
* @ retval " other negative error code " legitimate decoding errors
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*/
int avcodec_receive_frame ( AVCodecContext * avctx , AVFrame * frame ) ;
/**
* Supply a raw video or audio frame to the encoder . Use avcodec_receive_packet ( )
* to retrieve buffered output packets .
*
* @ param avctx codec context
* @ param [ in ] frame AVFrame containing the raw audio or video frame to be encoded .
* Ownership of the frame remains with the caller , and the
* encoder will not write to the frame . The encoder may create
* a reference to the frame data ( or copy it if the frame is
* not reference - counted ) .
* It can be NULL , in which case it is considered a flush
* packet . This signals the end of the stream . If the encoder
* still has packets buffered , it will return them after this
* call . Once flushing mode has been entered , additional flush
* packets are ignored , and sending frames will return
* AVERROR_EOF .
*
* For audio :
* If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set , then each frame
* can have any number of samples .
* If it is not set , frame - > nb_samples must be equal to
* avctx - > frame_size for all frames except the last .
* The final frame may be smaller than avctx - > frame_size .
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* @ retval 0 success
* @ retval AVERROR ( EAGAIN ) input is not accepted in the current state - user must
* read output with avcodec_receive_packet ( ) ( once all
* output is read , the packet should be resent , and the
* call will not fail with EAGAIN ) .
* @ retval AVERROR_EOF the encoder has been flushed , and no new frames can
* be sent to it
* @ retval AVERROR ( EINVAL ) codec not opened , it is a decoder , or requires flush
* @ retval AVERROR ( ENOMEM ) failed to add packet to internal queue , or similar
* @ retval " another negative error code " legitimate encoding errors
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*/
int avcodec_send_frame ( AVCodecContext * avctx , const AVFrame * frame ) ;
/**
* Read encoded data from the encoder .
*
* @ param avctx codec context
* @ param avpkt This will be set to a reference - counted packet allocated by the
* encoder . Note that the function will always call
* av_packet_unref ( avpkt ) before doing anything else .
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* @ retval 0 success
* @ retval AVERROR ( EAGAIN ) output is not available in the current state - user must
* try to send input
* @ retval AVERROR_EOF the encoder has been fully flushed , and there will be no
* more output packets
* @ retval AVERROR ( EINVAL ) codec not opened , or it is a decoder
* @ retval " another negative error code " legitimate encoding errors
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*/
int avcodec_receive_packet ( AVCodecContext * avctx , AVPacket * avpkt ) ;
/**
* Create and return a AVHWFramesContext with values adequate for hardware
* decoding . This is meant to get called from the get_format callback , and is
* a helper for preparing a AVHWFramesContext for AVCodecContext . hw_frames_ctx .
* This API is for decoding with certain hardware acceleration modes / APIs only .
*
* The returned AVHWFramesContext is not initialized . The caller must do this
* with av_hwframe_ctx_init ( ) .
*
* Calling this function is not a requirement , but makes it simpler to avoid
* codec or hardware API specific details when manually allocating frames .
*
* Alternatively to this , an API user can set AVCodecContext . hw_device_ctx ,
* which sets up AVCodecContext . hw_frames_ctx fully automatically , and makes
* it unnecessary to call this function or having to care about
* AVHWFramesContext initialization at all .
*
* There are a number of requirements for calling this function :
*
* - It must be called from get_format with the same avctx parameter that was
* passed to get_format . Calling it outside of get_format is not allowed , and
* can trigger undefined behavior .
* - The function is not always supported ( see description of return values ) .
* Even if this function returns successfully , hwaccel initialization could
* fail later . ( The degree to which implementations check whether the stream
* is actually supported varies . Some do this check only after the user ' s
* get_format callback returns . )
* - The hw_pix_fmt must be one of the choices suggested by get_format . If the
* user decides to use a AVHWFramesContext prepared with this API function ,
* the user must return the same hw_pix_fmt from get_format .
* - The device_ref passed to this function must support the given hw_pix_fmt .
* - After calling this API function , it is the user ' s responsibility to
* initialize the AVHWFramesContext ( returned by the out_frames_ref parameter ) ,
* and to set AVCodecContext . hw_frames_ctx to it . If done , this must be done
* before returning from get_format ( this is implied by the normal
* AVCodecContext . hw_frames_ctx API rules ) .
* - The AVHWFramesContext parameters may change every time time get_format is
* called . Also , AVCodecContext . hw_frames_ctx is reset before get_format . So
* you are inherently required to go through this process again on every
* get_format call .
* - It is perfectly possible to call this function without actually using
* the resulting AVHWFramesContext . One use - case might be trying to reuse a
* previously initialized AVHWFramesContext , and calling this API function
* only to test whether the required frame parameters have changed .
* - Fields that use dynamically allocated values of any kind must not be set
* by the user unless setting them is explicitly allowed by the documentation .
* If the user sets AVHWFramesContext . free and AVHWFramesContext . user_opaque ,
* the new free callback must call the potentially set previous free callback .
* This API call may set any dynamically allocated fields , including the free
* callback .
*
* The function will set at least the following fields on AVHWFramesContext
* ( potentially more , depending on hwaccel API ) :
*
* - All fields set by av_hwframe_ctx_alloc ( ) .
* - Set the format field to hw_pix_fmt .
* - Set the sw_format field to the most suited and most versatile format . ( An
* implication is that this will prefer generic formats over opaque formats
* with arbitrary restrictions , if possible . )
* - Set the width / height fields to the coded frame size , rounded up to the
* API - specific minimum alignment .
* - Only _if_ the hwaccel requires a pre - allocated pool : set the initial_pool_size
* field to the number of maximum reference surfaces possible with the codec ,
* plus 1 surface for the user to work ( meaning the user can safely reference
* at most 1 decoded surface at a time ) , plus additional buffering introduced
* by frame threading . If the hwaccel does not require pre - allocation , the
* field is left to 0 , and the decoder will allocate new surfaces on demand
* during decoding .
* - Possibly AVHWFramesContext . hwctx fields , depending on the underlying
* hardware API .
*
* Essentially , out_frames_ref returns the same as av_hwframe_ctx_alloc ( ) , but
* with basic frame parameters set .
*
* The function is stateless , and does not change the AVCodecContext or the
* device_ref AVHWDeviceContext .
*
* @ param avctx The context which is currently calling get_format , and which
* implicitly contains all state needed for filling the returned
* AVHWFramesContext properly .
* @ param device_ref A reference to the AVHWDeviceContext describing the device
* which will be used by the hardware decoder .
* @ param hw_pix_fmt The hwaccel format you are going to return from get_format .
* @ param out_frames_ref On success , set to a reference to an _uninitialized_
* AVHWFramesContext , created from the given device_ref .
* Fields will be set to values required for decoding .
* Not changed if an error is returned .
* @ return zero on success , a negative value on error . The following error codes
* have special semantics :
* AVERROR ( ENOENT ) : the decoder does not support this functionality . Setup
* is always manual , or it is a decoder which does not
* support setting AVCodecContext . hw_frames_ctx at all ,
* or it is a software format .
* AVERROR ( EINVAL ) : it is known that hardware decoding is not supported for
* this configuration , or the device_ref is not supported
* for the hwaccel referenced by hw_pix_fmt .
*/
int avcodec_get_hw_frames_parameters ( AVCodecContext * avctx ,
AVBufferRef * device_ref ,
enum AVPixelFormat hw_pix_fmt ,
AVBufferRef * * out_frames_ref ) ;
/**
* @ defgroup lavc_parsing Frame parsing
* @ {
*/
enum AVPictureStructure {
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AV_PICTURE_STRUCTURE_UNKNOWN , ///< unknown
AV_PICTURE_STRUCTURE_TOP_FIELD , ///< coded as top field
AV_PICTURE_STRUCTURE_BOTTOM_FIELD , ///< coded as bottom field
AV_PICTURE_STRUCTURE_FRAME , ///< coded as frame
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} ;
typedef struct AVCodecParserContext {
void * priv_data ;
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const struct AVCodecParser * parser ;
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int64_t frame_offset ; /* offset of the current frame */
int64_t cur_offset ; /* current offset
( incremented by each av_parser_parse ( ) ) */
int64_t next_frame_offset ; /* offset of the next frame */
/* video info */
int pict_type ; /* XXX: Put it back in AVCodecContext. */
/**
* This field is used for proper frame duration computation in lavf .
* It signals , how much longer the frame duration of the current frame
* is compared to normal frame duration .
*
* frame_duration = ( 1 + repeat_pict ) * time_base
*
* It is used by codecs like H .264 to display telecined material .
*/
int repeat_pict ; /* XXX: Put it back in AVCodecContext. */
int64_t pts ; /* pts of the current frame */
int64_t dts ; /* dts of the current frame */
/* private data */
int64_t last_pts ;
int64_t last_dts ;
int fetch_timestamp ;
# define AV_PARSER_PTS_NB 4
int cur_frame_start_index ;
int64_t cur_frame_offset [ AV_PARSER_PTS_NB ] ;
int64_t cur_frame_pts [ AV_PARSER_PTS_NB ] ;
int64_t cur_frame_dts [ AV_PARSER_PTS_NB ] ;
int flags ;
# define PARSER_FLAG_COMPLETE_FRAMES 0x0001
# define PARSER_FLAG_ONCE 0x0002
/// Set if the parser has a valid file offset
# define PARSER_FLAG_FETCHED_OFFSET 0x0004
# define PARSER_FLAG_USE_CODEC_TS 0x1000
int64_t offset ; ///< byte offset from starting packet start
int64_t cur_frame_end [ AV_PARSER_PTS_NB ] ;
/**
* Set by parser to 1 for key frames and 0 for non - key frames .
* It is initialized to - 1 , so if the parser doesn ' t set this flag ,
* old - style fallback using AV_PICTURE_TYPE_I picture type as key frames
* will be used .
*/
int key_frame ;
// Timestamp generation support:
/**
* Synchronization point for start of timestamp generation .
*
* Set to > 0 for sync point , 0 for no sync point and < 0 for undefined
* ( default ) .
*
* For example , this corresponds to presence of H .264 buffering period
* SEI message .
*/
int dts_sync_point ;
/**
* Offset of the current timestamp against last timestamp sync point in
* units of AVCodecContext . time_base .
*
* Set to INT_MIN when dts_sync_point unused . Otherwise , it must
* contain a valid timestamp offset .
*
* Note that the timestamp of sync point has usually a nonzero
* dts_ref_dts_delta , which refers to the previous sync point . Offset of
* the next frame after timestamp sync point will be usually 1.
*
* For example , this corresponds to H .264 cpb_removal_delay .
*/
int dts_ref_dts_delta ;
/**
* Presentation delay of current frame in units of AVCodecContext . time_base .
*
* Set to INT_MIN when dts_sync_point unused . Otherwise , it must
* contain valid non - negative timestamp delta ( presentation time of a frame
* must not lie in the past ) .
*
* This delay represents the difference between decoding and presentation
* time of the frame .
*
* For example , this corresponds to H .264 dpb_output_delay .
*/
int pts_dts_delta ;
/**
* Position of the packet in file .
*
* Analogous to cur_frame_pts / dts
*/
int64_t cur_frame_pos [ AV_PARSER_PTS_NB ] ;
/**
* Byte position of currently parsed frame in stream .
*/
int64_t pos ;
/**
* Previous frame byte position .
*/
int64_t last_pos ;
/**
* Duration of the current frame .
* For audio , this is in units of 1 / AVCodecContext . sample_rate .
* For all other types , this is in units of AVCodecContext . time_base .
*/
int duration ;
enum AVFieldOrder field_order ;
/**
* Indicate whether a picture is coded as a frame , top field or bottom field .
*
* For example , H .264 field_pic_flag equal to 0 corresponds to
* AV_PICTURE_STRUCTURE_FRAME . An H .264 picture with field_pic_flag
* equal to 1 and bottom_field_flag equal to 0 corresponds to
* AV_PICTURE_STRUCTURE_TOP_FIELD .
*/
enum AVPictureStructure picture_structure ;
/**
* Picture number incremented in presentation or output order .
* This field may be reinitialized at the first picture of a new sequence .
*
* For example , this corresponds to H .264 PicOrderCnt .
*/
int output_picture_number ;
/**
* Dimensions of the decoded video intended for presentation .
*/
int width ;
int height ;
/**
* Dimensions of the coded video .
*/
int coded_width ;
int coded_height ;
/**
* The format of the coded data , corresponds to enum AVPixelFormat for video
* and for enum AVSampleFormat for audio .
*
* Note that a decoder can have considerable freedom in how exactly it
* decodes the data , so the format reported here might be different from the
* one returned by a decoder .
*/
int format ;
} AVCodecParserContext ;
typedef struct AVCodecParser {
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int codec_ids [ 7 ] ; /* several codec IDs are permitted */
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int priv_data_size ;
int ( * parser_init ) ( AVCodecParserContext * s ) ;
/* This callback never returns an error, a negative value means that
* the frame start was in a previous packet . */
int ( * parser_parse ) ( AVCodecParserContext * s ,
AVCodecContext * avctx ,
const uint8_t * * poutbuf , int * poutbuf_size ,
const uint8_t * buf , int buf_size ) ;
void ( * parser_close ) ( AVCodecParserContext * s ) ;
int ( * split ) ( AVCodecContext * avctx , const uint8_t * buf , int buf_size ) ;
} AVCodecParser ;
/**
* Iterate over all registered codec parsers .
*
* @ param opaque a pointer where libavcodec will store the iteration state . Must
* point to NULL to start the iteration .
*
* @ return the next registered codec parser or NULL when the iteration is
* finished
*/
const AVCodecParser * av_parser_iterate ( void * * opaque ) ;
AVCodecParserContext * av_parser_init ( int codec_id ) ;
/**
* Parse a packet .
*
* @ param s parser context .
* @ param avctx codec context .
* @ param poutbuf set to pointer to parsed buffer or NULL if not yet finished .
* @ param poutbuf_size set to size of parsed buffer or zero if not yet finished .
* @ param buf input buffer .
* @ param buf_size buffer size in bytes without the padding . I . e . the full buffer
size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE .
To signal EOF , this should be 0 ( so that the last frame
can be output ) .
* @ param pts input presentation timestamp .
* @ param dts input decoding timestamp .
* @ param pos input byte position in stream .
* @ return the number of bytes of the input bitstream used .
*
* Example :
* @ code
* while ( in_len ) {
* len = av_parser_parse2 ( myparser , AVCodecContext , & data , & size ,
* in_data , in_len ,
* pts , dts , pos ) ;
* in_data + = len ;
* in_len - = len ;
*
* if ( size )
* decode_frame ( data , size ) ;
* }
* @ endcode
*/
int av_parser_parse2 ( AVCodecParserContext * s ,
AVCodecContext * avctx ,
uint8_t * * poutbuf , int * poutbuf_size ,
const uint8_t * buf , int buf_size ,
int64_t pts , int64_t dts ,
int64_t pos ) ;
void av_parser_close ( AVCodecParserContext * s ) ;
/**
* @ }
* @ }
*/
/**
* @ addtogroup lavc_encoding
* @ {
*/
int avcodec_encode_subtitle ( AVCodecContext * avctx , uint8_t * buf , int buf_size ,
const AVSubtitle * sub ) ;
/**
* @ }
*/
/**
* @ defgroup lavc_misc Utility functions
* @ ingroup libavc
*
* Miscellaneous utility functions related to both encoding and decoding
* ( or neither ) .
* @ {
*/
/**
* @ defgroup lavc_misc_pixfmt Pixel formats
*
* Functions for working with pixel formats .
* @ {
*/
/**
* Return a value representing the fourCC code associated to the
* pixel format pix_fmt , or 0 if no associated fourCC code can be
* found .
*/
unsigned int avcodec_pix_fmt_to_codec_tag ( enum AVPixelFormat pix_fmt ) ;
/**
* Find the best pixel format to convert to given a certain source pixel
* format . When converting from one pixel format to another , information loss
* may occur . For example , when converting from RGB24 to GRAY , the color
* information will be lost . Similarly , other losses occur when converting from
* some formats to other formats . avcodec_find_best_pix_fmt_of_2 ( ) searches which of
* the given pixel formats should be used to suffer the least amount of loss .
* The pixel formats from which it chooses one , are determined by the
* pix_fmt_list parameter .
*
*
* @ param [ in ] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
* @ param [ in ] src_pix_fmt source pixel format
* @ param [ in ] has_alpha Whether the source pixel format alpha channel is used .
* @ param [ out ] loss_ptr Combination of flags informing you what kind of losses will occur .
* @ return The best pixel format to convert to or - 1 if none was found .
*/
enum AVPixelFormat avcodec_find_best_pix_fmt_of_list ( const enum AVPixelFormat * pix_fmt_list ,
enum AVPixelFormat src_pix_fmt ,
int has_alpha , int * loss_ptr ) ;
enum AVPixelFormat avcodec_default_get_format ( struct AVCodecContext * s , const enum AVPixelFormat * fmt ) ;
/**
* @ }
*/
void avcodec_string ( char * buf , int buf_size , AVCodecContext * enc , int encode ) ;
int avcodec_default_execute ( AVCodecContext * c , int ( * func ) ( AVCodecContext * c2 , void * arg2 ) , void * arg , int * ret , int count , int size ) ;
int avcodec_default_execute2 ( AVCodecContext * c , int ( * func ) ( AVCodecContext * c2 , void * arg2 , int , int ) , void * arg , int * ret , int count ) ;
//FIXME func typedef
/**
* Fill AVFrame audio data and linesize pointers .
*
* The buffer buf must be a preallocated buffer with a size big enough
* to contain the specified samples amount . The filled AVFrame data
* pointers will point to this buffer .
*
* AVFrame extended_data channel pointers are allocated if necessary for
* planar audio .
*
* @ param frame the AVFrame
* frame - > nb_samples must be set prior to calling the
* function . This function fills in frame - > data ,
* frame - > extended_data , frame - > linesize [ 0 ] .
* @ param nb_channels channel count
* @ param sample_fmt sample format
* @ param buf buffer to use for frame data
* @ param buf_size size of buffer
* @ param align plane size sample alignment ( 0 = default )
* @ return > = 0 on success , negative error code on failure
* @ todo return the size in bytes required to store the samples in
* case of success , at the next libavutil bump
*/
int avcodec_fill_audio_frame ( AVFrame * frame , int nb_channels ,
enum AVSampleFormat sample_fmt , const uint8_t * buf ,
int buf_size , int align ) ;
/**
* Reset the internal codec state / flush internal buffers . Should be called
* e . g . when seeking or when switching to a different stream .
*
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* @ note for decoders , this function just releases any references the decoder
* might keep internally , but the caller ' s references remain valid .
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*
* @ note for encoders , this function will only do something if the encoder
* declares support for AV_CODEC_CAP_ENCODER_FLUSH . When called , the encoder
* will drain any remaining packets , and can then be re - used for a different
* stream ( as opposed to sending a null frame which will leave the encoder
* in a permanent EOF state after draining ) . This can be desirable if the
* cost of tearing down and replacing the encoder instance is high .
*/
void avcodec_flush_buffers ( AVCodecContext * avctx ) ;
/**
* Return audio frame duration .
*
* @ param avctx codec context
* @ param frame_bytes size of the frame , or 0 if unknown
* @ return frame duration , in samples , if known . 0 if not able to
* determine .
*/
int av_get_audio_frame_duration ( AVCodecContext * avctx , int frame_bytes ) ;
/* memory */
/**
* Same behaviour av_fast_malloc but the buffer has additional
* AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
*
* In addition the whole buffer will initially and after resizes
* be 0 - initialized so that no uninitialized data will ever appear .
*/
void av_fast_padded_malloc ( void * ptr , unsigned int * size , size_t min_size ) ;
/**
* Same behaviour av_fast_padded_malloc except that buffer will always
* be 0 - initialized after call .
*/
void av_fast_padded_mallocz ( void * ptr , unsigned int * size , size_t min_size ) ;
/**
* @ return a positive value if s is open ( i . e . avcodec_open2 ( ) was called on it
* with no corresponding avcodec_close ( ) ) , 0 otherwise .
*/
int avcodec_is_open ( AVCodecContext * s ) ;
/**
* @ }
*/
# endif /* AVCODEC_AVCODEC_H */
