ffmpeg:avcodeccontext
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AVCodecContext
Defined in avcodec.h
/**
* main external API structure
*/
typedef struct AVCodecContext {
/**
* information on struct for av_log
* - set by avcodec_alloc_context
*/
AVClass *av_class;
/**
* the average bitrate
* - encoding: Set by user; unused for constant quantizer encoding.
* - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
*/
int 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;
/**
* CODEC_FLAG_*.
* - encoding: Set by user.
* - decoding: Set by user.
*/
int flags;
/**
* Some codecs need additional format info. It is stored here.
* If any muxer uses this then ALL demuxers/parsers AND encoders for the
* specific codec MUST set it correctly otherwise stream copy breaks.
* In general use of this field by muxers is not recommanded.
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec. (FIXME: Is this OK?)
*/
int sub_id;
/**
* Motion estimation algorithm used for video coding.
* 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
* 8 (umh), 9 (iter) [7, 8 are x264 specific, 9 is snow specific]
* - encoding: MUST be set by user.
* - decoding: unused
*/
int me_method;
/**
* some codecs need / can use extradata like Huffman tables.
* mjpeg: Huffman tables
* rv10: additional flags
* mpeg4: global headers (they can be in the bitstream or here)
* The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
* than extradata_size to avoid prolems if it is read with the bitstream reader.
* The bytewise contents of extradata must not depend on the architecture or CPU endianness.
* - 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.
* - encoding: MUST be set by user.
* - decoding: Set by libavcodec.
*/
AVRational time_base;
/* video only */
/**
* picture width / height.
* - encoding: MUST be set by user.
* - decoding: Set by libavcodec.
* Note: For compatibility it is possible to set this instead of
* coded_width/height before decoding.
*/
int width, height;
#define FF_ASPECT_EXTENDED 15
/**
* 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 PIX_FMT_xxx.
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
enum PixelFormat pix_fmt;
/**
* Frame rate emulation. If not zero, the lower layer (i.e. format handler)
* has to read frames at native frame rate.
* - encoding: Set by user.
* - decoding: unused
*/
int rate_emu;
/**
* 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.
* - 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[4],
int y, int type, int height);
/* audio only */
int sample_rate; ///< samples per second
int channels;
/**
* audio sample format
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
enum SampleFormat sample_fmt; ///< sample format, currently unused
/* The following data should not be initialized. */
/**
* Samples per packet, initialized when calling 'init'.
*/
int frame_size;
int frame_number; ///< audio or video frame number
int real_pict_num; ///< Returns the real picture number of previous encoded frame.
/**
* Number of frames the decoded output will be delayed relative to
* the encoded input.
* - encoding: Set by libavcodec.
* - decoding: unused
*/
int delay;
/* - 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;
/**
* 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
* - encoding: Set by user.
* - decoding: unused
*/
float b_quant_factor;
/** obsolete FIXME remove */
int rc_strategy;
#define FF_RC_STRATEGY_XVID 1
int b_frame_strategy;
/**
* hurry up amount
* - encoding: unused
* - decoding: Set by user. 1-> Skip B-frames, 2-> Skip IDCT/dequant too, 5-> Skip everything except header
* @deprecated Deprecated in favor of skip_idct and skip_frame.
*/
int hurry_up;
struct AVCodec *codec;
void *priv_data;
#if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0)
/* unused, FIXME remove*/
int rtp_mode;
#endif
int rtp_payload_size; /* The size of the RTP payload: the coder will */
/* do its best to deliver a chunk with size */
/* below rtp_payload_size, the chunk will start */
/* with a start code on some codecs like H.263. */
/* This doesn't take account of any particular */
/* headers inside the transmitted RTP payload. */
/* The RTP callback: This function is called */
/* every time the encoder has a packet to send. */
/* It depends on the encoder if the data starts */
/* with a Start Code (it should). H.263 does. */
/* mb_nb contains the number of macroblocks */
/* encoded in the RTP payload. */
void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
/* statistics, used for 2-pass encoding */
int mv_bits;
int header_bits;
int i_tex_bits;
int p_tex_bits;
int i_count;
int p_count;
int skip_count;
int misc_bits;
/**
* number of bits used for the previously encoded frame
* - encoding: Set by libavcodec.
* - decoding: unused
*/
int frame_bits;
/**
* Private data of the user, can be used to carry app specific stuff.
* - encoding: Set by user.
* - decoding: Set by user.
*/
void *opaque;
char codec_name[32];
enum CodecType codec_type; /* see CODEC_TYPE_xxx */
enum CodecID codec_id; /* see 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 then 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;
/**
* 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_OLD_MSMPEG4 2
#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_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
#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_FAKE_SCALABILITY 16 //Autodetection should work 100%.
/**
* luma single coefficient elimination threshold
* - encoding: Set by user.
* - decoding: unused
*/
int luma_elim_threshold;
/**
* chroma single coeff elimination threshold
* - encoding: Set by user.
* - decoding: unused
*/
int chroma_elim_threshold;
/**
* strictly follow the standard (MPEG4, ...).
* - encoding: Set by user.
* - decoding: unused
*/
int strict_std_compliance;
#define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to a older more strict version of the spec or reference software.
#define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
#define FF_COMPLIANCE_NORMAL 0
#define FF_COMPLIANCE_INOFFICIAL -1 ///< Allow inofficial extensions.
#define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
/**
* qscale offset 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_offset;
/**
* Error resilience; higher values will detect more errors but may
* misdetect some more or less valid parts as errors.
* - encoding: unused
* - decoding: Set by user.
*/
int error_resilience;
#define FF_ER_CAREFUL 1
#define FF_ER_COMPLIANT 2
#define FF_ER_AGGRESSIVE 3
#define FF_ER_VERY_AGGRESSIVE 4
/**
* Called at the beginning of each frame to get a buffer for it.
* If pic.reference is set then the frame will be read later by libavcodec.
* avcodec_align_dimensions() should be used to find the required width and
* height, as they normally need to be rounded up to the next multiple of 16.
* - encoding: unused
* - decoding: Set by libavcodec., user can override.
*/
int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
/**
* Called to release buffers which where allocated with get_buffer.
* A released buffer can be reused in get_buffer().
* pic.data[*] must be set to NULL.
* - encoding: unused
* - decoding: Set by libavcodec., user can override.
*/
void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
/**
* If 1 the stream has a 1 frame delay during decoding.
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec.
*/
int has_b_frames;
/**
* number of bytes per packet if constant and known or 0
* Used by some WAV based audio codecs.
*/
int block_align;
int parse_only; /* - decoding only: If true, only parsing is done
(function avcodec_parse_frame()). The frame
data is returned. Only MPEG codecs support this now. */
/**
* 0-> h263 quant 1-> mpeg quant
* - encoding: Set by user.
* - decoding: unused
*/
int mpeg_quant;
/**
* 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;
/**
* ratecontrol qmin qmax limiting method
* 0-> clipping, 1-> use a nice continous function to limit qscale wthin qmin/qmax.
* - encoding: Set by user.
* - decoding: unused
*/
float rc_qsquish;
float rc_qmod_amp;
int rc_qmod_freq;
/**
* ratecontrol override, see RcOverride
* - encoding: Allocated/set/freed by user.
* - decoding: unused
*/
RcOverride *rc_override;
int rc_override_count;
/**
* rate control equation
* - encoding: Set by user
* - decoding: unused
*/
char *rc_eq;
/**
* maximum bitrate
* - encoding: Set by user.
* - decoding: unused
*/
int rc_max_rate;
/**
* minimum bitrate
* - encoding: Set by user.
* - decoding: unused
*/
int rc_min_rate;
/**
* decoder bitstream buffer size
* - encoding: Set by user.
* - decoding: unused
*/
int rc_buffer_size;
float rc_buffer_aggressivity;
/**
* 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;
/**
* initial complexity for pass1 ratecontrol
* - encoding: Set by user.
* - decoding: unused
*/
float rc_initial_cplx;
/**
* 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_MLIB 4
#define FF_DCT_ALTIVEC 5
#define FF_DCT_FAAN 6
/**
* 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;
/* for binary compatibility */
int unused;
/**
* 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_LIBMPEG2MMX 4
#define FF_IDCT_PS2 5
#define FF_IDCT_MLIB 6
#define FF_IDCT_ARM 7
#define FF_IDCT_ALTIVEC 8
#define FF_IDCT_SH4 9
#define FF_IDCT_SIMPLEARM 10
#define FF_IDCT_H264 11
#define FF_IDCT_VP3 12
#define FF_IDCT_IPP 13
#define FF_IDCT_XVIDMMX 14
#define FF_IDCT_CAVS 15
#define FF_IDCT_SIMPLEARMV5TE 16
#define FF_IDCT_SIMPLEARMV6 17
/**
* 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;
/**
* error concealment flags
* - encoding: unused
* - decoding: Set by user.
*/
int error_concealment;
#define FF_EC_GUESS_MVS 1
#define FF_EC_DEBLOCK 2
/**
* dsp_mask could be add used to disable unwanted CPU features
* CPU features (i.e. MMX, SSE. ...)
*
* With the FORCE flag you may instead enable given CPU features.
* (Dangerous: Usable in case of misdetection, improper usage however will
* result into program crash.)
*/
unsigned dsp_mask;
#define FF_MM_FORCE 0x80000000 /* Force usage of selected flags (OR) */
/* lower 16 bits - CPU features */
#define FF_MM_MMX 0x0001 /* standard MMX */
#define FF_MM_3DNOW 0x0004 /* AMD 3DNOW */
#define FF_MM_MMXEXT 0x0002 /* SSE integer functions or AMD MMX ext */
#define FF_MM_SSE 0x0008 /* SSE functions */
#define FF_MM_SSE2 0x0010 /* PIV SSE2 functions */
#define FF_MM_3DNOWEXT 0x0020 /* AMD 3DNowExt */
#define FF_MM_SSE3 0x0040 /* Prescott SSE3 functions */
#define FF_MM_SSSE3 0x0080 /* Conroe SSSE3 functions */
#define FF_MM_IWMMXT 0x0100 /* XScale IWMMXT */
/**
* bits per sample/pixel from the demuxer (needed for huffyuv).
* - encoding: Set by libavcodec.
* - decoding: Set by user.
*/
int bits_per_sample;
/**
* prediction method (needed for huffyuv)
* - encoding: Set by user.
* - decoding: unused
*/
int prediction_method;
#define FF_PRED_LEFT 0
#define FF_PRED_PLANE 1
#define FF_PRED_MEDIAN 2
/**
* sample aspect ratio (0 if unknown)
* 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;
/**
* the picture in the bitstream
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec.
*/
AVFrame *coded_frame;
/**
* 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_MV 32
#define FF_DEBUG_DCT_COEFF 0x00000040
#define FF_DEBUG_SKIP 0x00000080
#define FF_DEBUG_STARTCODE 0x00000100
#define FF_DEBUG_PTS 0x00000200
#define FF_DEBUG_ER 0x00000400
#define FF_DEBUG_MMCO 0x00000800
#define FF_DEBUG_BUGS 0x00001000
#define FF_DEBUG_VIS_QP 0x00002000
#define FF_DEBUG_VIS_MB_TYPE 0x00004000
/**
* debug
* - encoding: Set by user.
* - decoding: Set by user.
*/
int debug_mv;
#define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
#define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
#define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
/**
* error
* - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
* - decoding: unused
*/
uint64_t error[4];
/**
* minimum MB quantizer
* - encoding: unused
* - decoding: unused
*/
int mb_qmin;
/**
* maximum MB quantizer
* - encoding: unused
* - decoding: unused
*/
int mb_qmax;
/**
* 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_CHROMA 256
/**
* ME diamond size & shape
* - encoding: Set by user.
* - decoding: unused
*/
int dia_size;
/**
* amount of previous MV predictors (2a+1 x 2a+1 square)
* - encoding: Set by user.
* - decoding: unused
*/
int last_predictor_count;
/**
* prepass for motion estimation
* - encoding: Set by user.
* - decoding: unused
*/
int pre_me;
/**
* 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;
/**
* callback to negotiate the pixelFormat
* @param fmt is the list of formats which are supported by the codec,
* it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
* The first is always the native one.
* @return the chosen format
* - encoding: unused
* - decoding: Set by user, if not set the native format will be chosen.
*/
enum PixelFormat (*get_format)(struct AVCodecContext *s, const enum PixelFormat * fmt);
/**
* DTG active format information (additional aspect ratio
* information only used in DVB MPEG-2 transport streams)
* 0 if not set.
*
* - encoding: unused
* - decoding: Set by decoder.
*/
int dtg_active_format;
#define FF_DTG_AFD_SAME 8
#define FF_DTG_AFD_4_3 9
#define FF_DTG_AFD_16_9 10
#define FF_DTG_AFD_14_9 11
#define FF_DTG_AFD_4_3_SP_14_9 13
#define FF_DTG_AFD_16_9_SP_14_9 14
#define FF_DTG_AFD_SP_4_3 15
/**
* maximum motion estimation search range in subpel units
* If 0 then no limit.
*
* - encoding: Set by user.
* - decoding: unused
*/
int me_range;
/**
* intra quantizer bias
* - encoding: Set by user.
* - decoding: unused
*/
int intra_quant_bias;
#define FF_DEFAULT_QUANT_BIAS 999999
/**
* inter quantizer bias
* - encoding: Set by user.
* - decoding: unused
*/
int inter_quant_bias;
/**
* color table ID
* - encoding: unused
* - decoding: Which clrtable should be used for 8bit RGB images.
* Tables have to be stored somewhere. FIXME
*/
int color_table_id;
/**
* internal_buffer count
* Don't touch, used by libavcodec default_get_buffer().
*/
int internal_buffer_count;
/**
* internal_buffers
* Don't touch, used by libavcodec default_get_buffer().
*/
void *internal_buffer;
#define FF_LAMBDA_SHIFT 7
#define FF_LAMBDA_SCALE (1<<FF_LAMBDA_SHIFT)
#define FF_QP2LAMBDA 118 ///< factor to convert from H.263 QP to lambda
#define FF_LAMBDA_MAX (256*128-1)
#define FF_QUALITY_SCALE FF_LAMBDA_SCALE //FIXME maybe remove
/**
* 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;
#define FF_CODER_TYPE_VLC 0
#define FF_CODER_TYPE_AC 1
#define FF_CODER_TYPE_RAW 2
#define FF_CODER_TYPE_RLE 3
#define FF_CODER_TYPE_DEFLATE 4
/**
* coder type
* - encoding: Set by user.
* - decoding: unused
*/
int coder_type;
/**
* context model
* - encoding: Set by user.
* - decoding: unused
*/
int context_model;
#if 0
/**
*
* - encoding: unused
* - decoding: Set by user.
*/
uint8_t * (*realloc)(struct AVCodecContext *s, uint8_t *buf, int buf_size);
#endif
/**
* 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 (MPEG2 field pics)
#define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
/**
* XVideo Motion Acceleration
* - encoding: forbidden
* - decoding: set by decoder
*/
int xvmc_acceleration;
/**
* 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 distoration
/**
* custom intra quantization matrix
* - encoding: Set by user, can be NULL.
* - decoding: Set by libavcodec.
*/
uint16_t *intra_matrix;
/**
* custom inter quantization matrix
* - encoding: Set by user, can be NULL.
* - decoding: Set by libavcodec.
*/
uint16_t *inter_matrix;
/**
* fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
* This is used to work around some encoder bugs.
* - encoding: unused
* - decoding: Set by user, will be converted to uppercase by libavcodec during init.
*/
unsigned int stream_codec_tag;
/**
* scene change detection threshold
* 0 is default, larger means fewer detected scene changes.
* - encoding: Set by user.
* - decoding: unused
*/
int scenechange_threshold;
/**
* minimum Lagrange multipler
* - encoding: Set by user.
* - decoding: unused
*/
int lmin;
/**
* maximum Lagrange multipler
* - encoding: Set by user.
* - decoding: unused
*/
int lmax;
/**
* palette control structure
* - encoding: ??? (no palette-enabled encoder yet)
* - decoding: Set by user.
*/
struct AVPaletteControl *palctrl;
/**
* noise reduction strength
* - encoding: Set by user.
* - decoding: unused
*/
int noise_reduction;
/**
* Called at the beginning of a frame to get cr buffer for it.
* Buffer type (size, hints) must be the same. libavcodec won't check it.
* libavcodec will pass previous buffer in pic, function should return
* same buffer or new buffer with old frame "painted" into it.
* If pic.data[0] == NULL must behave like get_buffer().
* - encoding: unused
* - decoding: Set by libavcodec., user can override
*/
int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
/**
* 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;
/**
*
* - encoding: Set by user.
* - decoding: unused
*/
int inter_threshold;
/**
* CODEC_FLAG2_*
* - encoding: Set by user.
* - decoding: Set by user.
*/
int flags2;
/**
* Simulates errors in the bitstream to test error concealment.
* - encoding: Set by user.
* - decoding: unused
*/
int error_rate;
/**
* MP3 antialias algorithm, see FF_AA_* below.
* - encoding: unused
* - decoding: Set by user.
*/
int antialias_algo;
#define FF_AA_AUTO 0
#define FF_AA_FASTINT 1 //not implemented yet
#define FF_AA_INT 2
#define FF_AA_FLOAT 3
/**
* quantizer noise shaping
* - encoding: Set by user.
* - decoding: unused
*/
int quantizer_noise_shaping;
/**
* 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;
/**
* 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);
/**
* thread opaque
* Can be used by execute() to store some per AVCodecContext stuff.
* - encoding: set by execute()
* - decoding: set by execute()
*/
void *thread_opaque;
/**
* Motion estimation threshold below which no motion estimation is
* performed, but instead the user specified motion vectors are used.
*
* - encoding: Set by user.
* - decoding: unused
*/
int me_threshold;
/**
* Macroblock threshold below which the user specified macroblock types will be used.
* - encoding: Set by user.
* - decoding: unused
*/
int mb_threshold;
/**
* precision of the intra DC coefficient - 8
* - encoding: Set by user.
* - decoding: unused
*/
int intra_dc_precision;
/**
* noise vs. sse weight for the nsse comparsion function
* - encoding: Set by user.
* - decoding: unused
*/
int nsse_weight;
/**
* 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;
/**
* profile
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
int profile;
#define FF_PROFILE_UNKNOWN -99
#define FF_PROFILE_AAC_MAIN 0
#define FF_PROFILE_AAC_LOW 1
#define FF_PROFILE_AAC_SSR 2
#define FF_PROFILE_AAC_LTP 3
/**
* level
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
int level;
#define FF_LEVEL_UNKNOWN -99
/**
* low resolution decoding, 1-> 1/2 size, 2->1/4 size
* - encoding: unused
* - decoding: Set by user.
*/
int lowres;
/**
* Bitstream width / height, may be different from width/height if lowres
* or other things are used.
* - encoding: unused
* - decoding: Set by user before init if known. Codec should override / dynamically change if needed.
*/
int coded_width, coded_height;
/**
* frame skip threshold
* - encoding: Set by user.
* - decoding: unused
*/
int frame_skip_threshold;
/**
* frame skip factor
* - encoding: Set by user.
* - decoding: unused
*/
int frame_skip_factor;
/**
* frame skip exponent
* - encoding: Set by user.
* - decoding: unused
*/
int frame_skip_exp;
/**
* frame skip comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int frame_skip_cmp;
/**
* Border processing masking, raises the quantizer for mbs on the borders
* of the picture.
* - encoding: Set by user.
* - decoding: unused
*/
float border_masking;
/**
* minimum MB lagrange multipler
* - encoding: Set by user.
* - decoding: unused
*/
int mb_lmin;
/**
* maximum MB lagrange multipler
* - encoding: Set by user.
* - decoding: unused
*/
int mb_lmax;
/**
*
* - encoding: Set by user.
* - decoding: unused
*/
int me_penalty_compensation;
/**
*
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_loop_filter;
/**
*
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_idct;
/**
*
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_frame;
/**
*
* - encoding: Set by user.
* - decoding: unused
*/
int bidir_refine;
/**
*
* - encoding: Set by user.
* - decoding: unused
*/
int brd_scale;
/**
* constant rate factor - quality-based VBR - values ~correspond to qps
* - encoding: Set by user.
* - decoding: unused
*/
float crf;
/**
* constant quantization parameter rate control method
* - encoding: Set by user.
* - decoding: unused
*/
int cqp;
/**
* minimum GOP size
* - encoding: Set by user.
* - decoding: unused
*/
int keyint_min;
/**
* number of reference frames
* - encoding: Set by user.
* - decoding: unused
*/
int refs;
/**
* chroma qp offset from luma
* - encoding: Set by user.
* - decoding: unused
*/
int chromaoffset;
/**
* Influences how often B-frames are used.
* - encoding: Set by user.
* - decoding: unused
*/
int bframebias;
/**
* trellis RD quantization
* - encoding: Set by user.
* - decoding: unused
*/
int trellis;
/**
* Reduce fluctuations in qp (before curve compression).
* - encoding: Set by user.
* - decoding: unused
*/
float complexityblur;
/**
* in-loop deblocking filter alphac0 parameter
* alpha is in the range -6...6
* - encoding: Set by user.
* - decoding: unused
*/
int deblockalpha;
/**
* in-loop deblocking filter beta parameter
* beta is in the range -6...6
* - encoding: Set by user.
* - decoding: unused
*/
int deblockbeta;
/**
* macroblock subpartition sizes to consider - p8x8, p4x4, b8x8, i8x8, i4x4
* - encoding: Set by user.
* - decoding: unused
*/
int partitions;
#define X264_PART_I4X4 0x001 /* Analyse i4x4 */
#define X264_PART_I8X8 0x002 /* Analyse i8x8 (requires 8x8 transform) */
#define X264_PART_P8X8 0x010 /* Analyse p16x8, p8x16 and p8x8 */
#define X264_PART_P4X4 0x020 /* Analyse p8x4, p4x8, p4x4 */
#define X264_PART_B8X8 0x100 /* Analyse b16x8, b8x16 and b8x8 */
/**
* direct MV prediction mode - 0 (none), 1 (spatial), 2 (temporal)
* - encoding: Set by user.
* - decoding: unused
*/
int directpred;
/**
* Audio cutoff bandwidth (0 means "automatic"), currently used only by FAAC.
* - encoding: Set by user.
* - decoding: unused
*/
int cutoff;
/**
* Multiplied by qscale for each frame and added to scene_change_score.
* - encoding: Set by user.
* - decoding: unused
*/
int scenechange_factor;
/**
*
* Note: Value depends upon the compare function used for fullpel ME.
* - encoding: Set by user.
* - decoding: unused
*/
int mv0_threshold;
/**
* Adjusts sensitivity of b_frame_strategy 1.
* - encoding: Set by user.
* - decoding: unused
*/
int b_sensitivity;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int compression_level;
#define FF_COMPRESSION_DEFAULT -1
/**
* Sets whether to use LPC mode - used by FLAC encoder.
* - encoding: Set by user.
* - decoding: unused
*/
int use_lpc;
/**
* LPC coefficient precision - used by FLAC encoder
* - encoding: Set by user.
* - decoding: unused
*/
int lpc_coeff_precision;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int min_prediction_order;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int max_prediction_order;
/**
* search method for selecting prediction order
* - encoding: Set by user.
* - decoding: unused
*/
int prediction_order_method;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int min_partition_order;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int max_partition_order;
/**
* GOP timecode frame start number, in non drop frame format
* - encoding: Set by user.
* - decoding: unused
*/
int64_t timecode_frame_start;
} AVCodecContext;
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ffmpeg/avcodeccontext.1195741274.txt.gz · Last modified: by deva