libavcodec/avcodec.h

   1 /*
   2  * copyright (c) 2001 Fabrice Bellard
   3  *
   4  * This file is part of Libav.
   5  *
   6  * Libav is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * Libav is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with Libav; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef AVCODEC_AVCODEC_H
  22 #define AVCODEC_AVCODEC_H
  23
  24 /**
  25  * @file
  26  * @ingroup libavc
  27  * Libavcodec external API header
  28  */
  29
  30 #include <errno.h>
  31 #include "libavutil/samplefmt.h"
  32 #include "libavutil/attributes.h"
  33 #include "libavutil/avutil.h"
  34 #include "libavutil/buffer.h"
  35 #include "libavutil/cpu.h"
  36 #include "libavutil/dict.h"
  37 #include "libavutil/frame.h"
  38 #include "libavutil/log.h"
  39 #include "libavutil/pixfmt.h"
  40 #include "libavutil/rational.h"
  41
  42 #include "version.h"
  43
  44 #if FF_API_FAST_MALLOC
  45 // to provide fast_*alloc
  46 #include "libavutil/mem.h"
  47 #endif
  48
  49 /**
  50  * @defgroup libavc Encoding/Decoding Library
  51  * @{
  52  *
  53  * @defgroup lavc_decoding Decoding
  54  * @{
  55  * @}
  56  *
  57  * @defgroup lavc_encoding Encoding
  58  * @{
  59  * @}
  60  *
  61  * @defgroup lavc_codec Codecs
  62  * @{
  63  * @defgroup lavc_codec_native Native Codecs
  64  * @{
  65  * @}
  66  * @defgroup lavc_codec_wrappers External library wrappers
  67  * @{
  68  * @}
  69  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
  70  * @{
  71  * @}
  72  * @}
  73  * @defgroup lavc_internal Internal
  74  * @{
  75  * @}
  76  * @}
  77  *
  78  */
  79
  80 /**
  81  * @defgroup lavc_core Core functions/structures.
  82  * @ingroup libavc
  83  *
  84  * Basic definitions, functions for querying libavcodec capabilities,
  85  * allocating core structures, etc.
  86  * @{
  87  */
  88
  89
  90 /**
  91  * Identify the syntax and semantics of the bitstream.
  92  * The principle is roughly:
  93  * Two decoders with the same ID can decode the same streams.
  94  * Two encoders with the same ID can encode compatible streams.
  95  * There may be slight deviations from the principle due to implementation
  96  * details.
  97  *
  98  * If you add a codec ID to this list, add it so that
  99  * 1. no value of a existing codec ID changes (that would break ABI),
 100  * 2. it is as close as possible to similar codecs.
 101  *
 102  * After adding new codec IDs, do not forget to add an entry to the codec
 103  * descriptor list and bump libavcodec minor version.
 104  */
 105 enum AVCodecID {
 106     AV_CODEC_ID_NONE,
 107
 108     /* video codecs */
 109     AV_CODEC_ID_MPEG1VIDEO,
 110     AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
 111 #if FF_API_XVMC
 112     AV_CODEC_ID_MPEG2VIDEO_XVMC,
 113 #endif /* FF_API_XVMC */
 114     AV_CODEC_ID_H261,
 115     AV_CODEC_ID_H263,
 116     AV_CODEC_ID_RV10,
 117     AV_CODEC_ID_RV20,
 118     AV_CODEC_ID_MJPEG,
 119     AV_CODEC_ID_MJPEGB,
 120     AV_CODEC_ID_LJPEG,
 121     AV_CODEC_ID_SP5X,
 122     AV_CODEC_ID_JPEGLS,
 123     AV_CODEC_ID_MPEG4,
 124     AV_CODEC_ID_RAWVIDEO,
 125     AV_CODEC_ID_MSMPEG4V1,
 126     AV_CODEC_ID_MSMPEG4V2,
 127     AV_CODEC_ID_MSMPEG4V3,
 128     AV_CODEC_ID_WMV1,
 129     AV_CODEC_ID_WMV2,
 130     AV_CODEC_ID_H263P,
 131     AV_CODEC_ID_H263I,
 132     AV_CODEC_ID_FLV1,
 133     AV_CODEC_ID_SVQ1,
 134     AV_CODEC_ID_SVQ3,
 135     AV_CODEC_ID_DVVIDEO,
 136     AV_CODEC_ID_HUFFYUV,
 137     AV_CODEC_ID_CYUV,
 138     AV_CODEC_ID_H264,
 139     AV_CODEC_ID_INDEO3,
 140     AV_CODEC_ID_VP3,
 141     AV_CODEC_ID_THEORA,
 142     AV_CODEC_ID_ASV1,
 143     AV_CODEC_ID_ASV2,
 144     AV_CODEC_ID_FFV1,
 145     AV_CODEC_ID_4XM,
 146     AV_CODEC_ID_VCR1,
 147     AV_CODEC_ID_CLJR,
 148     AV_CODEC_ID_MDEC,
 149     AV_CODEC_ID_ROQ,
 150     AV_CODEC_ID_INTERPLAY_VIDEO,
 151     AV_CODEC_ID_XAN_WC3,
 152     AV_CODEC_ID_XAN_WC4,
 153     AV_CODEC_ID_RPZA,
 154     AV_CODEC_ID_CINEPAK,
 155     AV_CODEC_ID_WS_VQA,
 156     AV_CODEC_ID_MSRLE,
 157     AV_CODEC_ID_MSVIDEO1,
 158     AV_CODEC_ID_IDCIN,
 159     AV_CODEC_ID_8BPS,
 160     AV_CODEC_ID_SMC,
 161     AV_CODEC_ID_FLIC,
 162     AV_CODEC_ID_TRUEMOTION1,
 163     AV_CODEC_ID_VMDVIDEO,
 164     AV_CODEC_ID_MSZH,
 165     AV_CODEC_ID_ZLIB,
 166     AV_CODEC_ID_QTRLE,
 167     AV_CODEC_ID_TSCC,
 168     AV_CODEC_ID_ULTI,
 169     AV_CODEC_ID_QDRAW,
 170     AV_CODEC_ID_VIXL,
 171     AV_CODEC_ID_QPEG,
 172     AV_CODEC_ID_PNG,
 173     AV_CODEC_ID_PPM,
 174     AV_CODEC_ID_PBM,
 175     AV_CODEC_ID_PGM,
 176     AV_CODEC_ID_PGMYUV,
 177     AV_CODEC_ID_PAM,
 178     AV_CODEC_ID_FFVHUFF,
 179     AV_CODEC_ID_RV30,
 180     AV_CODEC_ID_RV40,
 181     AV_CODEC_ID_VC1,
 182     AV_CODEC_ID_WMV3,
 183     AV_CODEC_ID_LOCO,
 184     AV_CODEC_ID_WNV1,
 185     AV_CODEC_ID_AASC,
 186     AV_CODEC_ID_INDEO2,
 187     AV_CODEC_ID_FRAPS,
 188     AV_CODEC_ID_TRUEMOTION2,
 189     AV_CODEC_ID_BMP,
 190     AV_CODEC_ID_CSCD,
 191     AV_CODEC_ID_MMVIDEO,
 192     AV_CODEC_ID_ZMBV,
 193     AV_CODEC_ID_AVS,
 194     AV_CODEC_ID_SMACKVIDEO,
 195     AV_CODEC_ID_NUV,
 196     AV_CODEC_ID_KMVC,
 197     AV_CODEC_ID_FLASHSV,
 198     AV_CODEC_ID_CAVS,
 199     AV_CODEC_ID_JPEG2000,
 200     AV_CODEC_ID_VMNC,
 201     AV_CODEC_ID_VP5,
 202     AV_CODEC_ID_VP6,
 203     AV_CODEC_ID_VP6F,
 204     AV_CODEC_ID_TARGA,
 205     AV_CODEC_ID_DSICINVIDEO,
 206     AV_CODEC_ID_TIERTEXSEQVIDEO,
 207     AV_CODEC_ID_TIFF,
 208     AV_CODEC_ID_GIF,
 209     AV_CODEC_ID_DXA,
 210     AV_CODEC_ID_DNXHD,
 211     AV_CODEC_ID_THP,
 212     AV_CODEC_ID_SGI,
 213     AV_CODEC_ID_C93,
 214     AV_CODEC_ID_BETHSOFTVID,
 215     AV_CODEC_ID_PTX,
 216     AV_CODEC_ID_TXD,
 217     AV_CODEC_ID_VP6A,
 218     AV_CODEC_ID_AMV,
 219     AV_CODEC_ID_VB,
 220     AV_CODEC_ID_PCX,
 221     AV_CODEC_ID_SUNRAST,
 222     AV_CODEC_ID_INDEO4,
 223     AV_CODEC_ID_INDEO5,
 224     AV_CODEC_ID_MIMIC,
 225     AV_CODEC_ID_RL2,
 226     AV_CODEC_ID_ESCAPE124,
 227     AV_CODEC_ID_DIRAC,
 228     AV_CODEC_ID_BFI,
 229     AV_CODEC_ID_CMV,
 230     AV_CODEC_ID_MOTIONPIXELS,
 231     AV_CODEC_ID_TGV,
 232     AV_CODEC_ID_TGQ,
 233     AV_CODEC_ID_TQI,
 234     AV_CODEC_ID_AURA,
 235     AV_CODEC_ID_AURA2,
 236     AV_CODEC_ID_V210X,
 237     AV_CODEC_ID_TMV,
 238     AV_CODEC_ID_V210,
 239     AV_CODEC_ID_DPX,
 240     AV_CODEC_ID_MAD,
 241     AV_CODEC_ID_FRWU,
 242     AV_CODEC_ID_FLASHSV2,
 243     AV_CODEC_ID_CDGRAPHICS,
 244     AV_CODEC_ID_R210,
 245     AV_CODEC_ID_ANM,
 246     AV_CODEC_ID_BINKVIDEO,
 247     AV_CODEC_ID_IFF_ILBM,
 248     AV_CODEC_ID_IFF_BYTERUN1,
 249     AV_CODEC_ID_KGV1,
 250     AV_CODEC_ID_YOP,
 251     AV_CODEC_ID_VP8,
 252     AV_CODEC_ID_PICTOR,
 253     AV_CODEC_ID_ANSI,
 254     AV_CODEC_ID_A64_MULTI,
 255     AV_CODEC_ID_A64_MULTI5,
 256     AV_CODEC_ID_R10K,
 257     AV_CODEC_ID_MXPEG,
 258     AV_CODEC_ID_LAGARITH,
 259     AV_CODEC_ID_PRORES,
 260     AV_CODEC_ID_JV,
 261     AV_CODEC_ID_DFA,
 262     AV_CODEC_ID_WMV3IMAGE,
 263     AV_CODEC_ID_VC1IMAGE,
 264     AV_CODEC_ID_UTVIDEO,
 265     AV_CODEC_ID_BMV_VIDEO,
 266     AV_CODEC_ID_VBLE,
 267     AV_CODEC_ID_DXTORY,
 268     AV_CODEC_ID_V410,
 269     AV_CODEC_ID_XWD,
 270     AV_CODEC_ID_CDXL,
 271     AV_CODEC_ID_XBM,
 272     AV_CODEC_ID_ZEROCODEC,
 273     AV_CODEC_ID_MSS1,
 274     AV_CODEC_ID_MSA1,
 275     AV_CODEC_ID_TSCC2,
 276     AV_CODEC_ID_MTS2,
 277     AV_CODEC_ID_CLLC,
 278     AV_CODEC_ID_MSS2,
 279     AV_CODEC_ID_VP9,
 280     AV_CODEC_ID_AIC,
 281     AV_CODEC_ID_ESCAPE130,
 282     AV_CODEC_ID_G2M,
 283     AV_CODEC_ID_WEBP,
 284     AV_CODEC_ID_HNM4_VIDEO,
 285     AV_CODEC_ID_HEVC,
 286     AV_CODEC_ID_FIC,
 287
 288     /* various PCM "codecs" */
 289     AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs
 290     AV_CODEC_ID_PCM_S16LE = 0x10000,
 291     AV_CODEC_ID_PCM_S16BE,
 292     AV_CODEC_ID_PCM_U16LE,
 293     AV_CODEC_ID_PCM_U16BE,
 294     AV_CODEC_ID_PCM_S8,
 295     AV_CODEC_ID_PCM_U8,
 296     AV_CODEC_ID_PCM_MULAW,
 297     AV_CODEC_ID_PCM_ALAW,
 298     AV_CODEC_ID_PCM_S32LE,
 299     AV_CODEC_ID_PCM_S32BE,
 300     AV_CODEC_ID_PCM_U32LE,
 301     AV_CODEC_ID_PCM_U32BE,
 302     AV_CODEC_ID_PCM_S24LE,
 303     AV_CODEC_ID_PCM_S24BE,
 304     AV_CODEC_ID_PCM_U24LE,
 305     AV_CODEC_ID_PCM_U24BE,
 306     AV_CODEC_ID_PCM_S24DAUD,
 307     AV_CODEC_ID_PCM_ZORK,
 308     AV_CODEC_ID_PCM_S16LE_PLANAR,
 309     AV_CODEC_ID_PCM_DVD,
 310     AV_CODEC_ID_PCM_F32BE,
 311     AV_CODEC_ID_PCM_F32LE,
 312     AV_CODEC_ID_PCM_F64BE,
 313     AV_CODEC_ID_PCM_F64LE,
 314     AV_CODEC_ID_PCM_BLURAY,
 315     AV_CODEC_ID_PCM_LXF,
 316     AV_CODEC_ID_S302M,
 317     AV_CODEC_ID_PCM_S8_PLANAR,
 318     AV_CODEC_ID_PCM_S24LE_PLANAR,
 319     AV_CODEC_ID_PCM_S32LE_PLANAR,
 320
 321     /* various ADPCM codecs */
 322     AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
 323     AV_CODEC_ID_ADPCM_IMA_WAV,
 324     AV_CODEC_ID_ADPCM_IMA_DK3,
 325     AV_CODEC_ID_ADPCM_IMA_DK4,
 326     AV_CODEC_ID_ADPCM_IMA_WS,
 327     AV_CODEC_ID_ADPCM_IMA_SMJPEG,
 328     AV_CODEC_ID_ADPCM_MS,
 329     AV_CODEC_ID_ADPCM_4XM,
 330     AV_CODEC_ID_ADPCM_XA,
 331     AV_CODEC_ID_ADPCM_ADX,
 332     AV_CODEC_ID_ADPCM_EA,
 333     AV_CODEC_ID_ADPCM_G726,
 334     AV_CODEC_ID_ADPCM_CT,
 335     AV_CODEC_ID_ADPCM_SWF,
 336     AV_CODEC_ID_ADPCM_YAMAHA,
 337     AV_CODEC_ID_ADPCM_SBPRO_4,
 338     AV_CODEC_ID_ADPCM_SBPRO_3,
 339     AV_CODEC_ID_ADPCM_SBPRO_2,
 340     AV_CODEC_ID_ADPCM_THP,
 341     AV_CODEC_ID_ADPCM_IMA_AMV,
 342     AV_CODEC_ID_ADPCM_EA_R1,
 343     AV_CODEC_ID_ADPCM_EA_R3,
 344     AV_CODEC_ID_ADPCM_EA_R2,
 345     AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
 346     AV_CODEC_ID_ADPCM_IMA_EA_EACS,
 347     AV_CODEC_ID_ADPCM_EA_XAS,
 348     AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
 349     AV_CODEC_ID_ADPCM_IMA_ISS,
 350     AV_CODEC_ID_ADPCM_G722,
 351     AV_CODEC_ID_ADPCM_IMA_APC,
 352
 353     /* AMR */
 354     AV_CODEC_ID_AMR_NB = 0x12000,
 355     AV_CODEC_ID_AMR_WB,
 356
 357     /* RealAudio codecs*/
 358     AV_CODEC_ID_RA_144 = 0x13000,
 359     AV_CODEC_ID_RA_288,
 360
 361     /* various DPCM codecs */
 362     AV_CODEC_ID_ROQ_DPCM = 0x14000,
 363     AV_CODEC_ID_INTERPLAY_DPCM,
 364     AV_CODEC_ID_XAN_DPCM,
 365     AV_CODEC_ID_SOL_DPCM,
 366
 367     /* audio codecs */
 368     AV_CODEC_ID_MP2 = 0x15000,
 369     AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
 370     AV_CODEC_ID_AAC,
 371     AV_CODEC_ID_AC3,
 372     AV_CODEC_ID_DTS,
 373     AV_CODEC_ID_VORBIS,
 374     AV_CODEC_ID_DVAUDIO,
 375     AV_CODEC_ID_WMAV1,
 376     AV_CODEC_ID_WMAV2,
 377     AV_CODEC_ID_MACE3,
 378     AV_CODEC_ID_MACE6,
 379     AV_CODEC_ID_VMDAUDIO,
 380     AV_CODEC_ID_FLAC,
 381     AV_CODEC_ID_MP3ADU,
 382     AV_CODEC_ID_MP3ON4,
 383     AV_CODEC_ID_SHORTEN,
 384     AV_CODEC_ID_ALAC,
 385     AV_CODEC_ID_WESTWOOD_SND1,
 386     AV_CODEC_ID_GSM, ///< as in Berlin toast format
 387     AV_CODEC_ID_QDM2,
 388     AV_CODEC_ID_COOK,
 389     AV_CODEC_ID_TRUESPEECH,
 390     AV_CODEC_ID_TTA,
 391     AV_CODEC_ID_SMACKAUDIO,
 392     AV_CODEC_ID_QCELP,
 393     AV_CODEC_ID_WAVPACK,
 394     AV_CODEC_ID_DSICINAUDIO,
 395     AV_CODEC_ID_IMC,
 396     AV_CODEC_ID_MUSEPACK7,
 397     AV_CODEC_ID_MLP,
 398     AV_CODEC_ID_GSM_MS, /* as found in WAV */
 399     AV_CODEC_ID_ATRAC3,
 400 #if FF_API_VOXWARE
 401     AV_CODEC_ID_VOXWARE,
 402 #endif
 403     AV_CODEC_ID_APE,
 404     AV_CODEC_ID_NELLYMOSER,
 405     AV_CODEC_ID_MUSEPACK8,
 406     AV_CODEC_ID_SPEEX,
 407     AV_CODEC_ID_WMAVOICE,
 408     AV_CODEC_ID_WMAPRO,
 409     AV_CODEC_ID_WMALOSSLESS,
 410     AV_CODEC_ID_ATRAC3P,
 411     AV_CODEC_ID_EAC3,
 412     AV_CODEC_ID_SIPR,
 413     AV_CODEC_ID_MP1,
 414     AV_CODEC_ID_TWINVQ,
 415     AV_CODEC_ID_TRUEHD,
 416     AV_CODEC_ID_MP4ALS,
 417     AV_CODEC_ID_ATRAC1,
 418     AV_CODEC_ID_BINKAUDIO_RDFT,
 419     AV_CODEC_ID_BINKAUDIO_DCT,
 420     AV_CODEC_ID_AAC_LATM,
 421     AV_CODEC_ID_QDMC,
 422     AV_CODEC_ID_CELT,
 423     AV_CODEC_ID_G723_1,
 424     AV_CODEC_ID_G729,
 425     AV_CODEC_ID_8SVX_EXP,
 426     AV_CODEC_ID_8SVX_FIB,
 427     AV_CODEC_ID_BMV_AUDIO,
 428     AV_CODEC_ID_RALF,
 429     AV_CODEC_ID_IAC,
 430     AV_CODEC_ID_ILBC,
 431     AV_CODEC_ID_OPUS,
 432     AV_CODEC_ID_COMFORT_NOISE,
 433     AV_CODEC_ID_TAK,
 434     AV_CODEC_ID_METASOUND,
 435
 436     /* subtitle codecs */
 437     AV_CODEC_ID_FIRST_SUBTITLE = 0x17000,          ///< A dummy ID pointing at the start of subtitle codecs.
 438     AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
 439     AV_CODEC_ID_DVB_SUBTITLE,
 440     AV_CODEC_ID_TEXT,  ///< raw UTF-8 text
 441     AV_CODEC_ID_XSUB,
 442     AV_CODEC_ID_SSA,
 443     AV_CODEC_ID_MOV_TEXT,
 444     AV_CODEC_ID_HDMV_PGS_SUBTITLE,
 445     AV_CODEC_ID_DVB_TELETEXT,
 446     AV_CODEC_ID_SRT,
 447
 448     /* other specific kind of codecs (generally used for attachments) */
 449     AV_CODEC_ID_FIRST_UNKNOWN = 0x18000,           ///< A dummy ID pointing at the start of various fake codecs.
 450     AV_CODEC_ID_TTF = 0x18000,
 451
 452     AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
 453
 454     AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
 455                                 * stream (only used by libavformat) */
 456     AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
 457                                 * stream (only used by libavformat) */
 458     AV_CODEC_ID_FFMETADATA = 0x21000,   ///< Dummy codec for streams containing only metadata information.
 459 };
 460
 461 /**
 462  * This struct describes the properties of a single codec described by an
 463  * AVCodecID.
 464  * @see avcodec_get_descriptor()
 465  */
 466 typedef struct AVCodecDescriptor {
 467     enum AVCodecID     id;
 468     enum AVMediaType type;
 469     /**
 470      * Name of the codec described by this descriptor. It is non-empty and
 471      * unique for each codec descriptor. It should contain alphanumeric
 472      * characters and '_' only.
 473      */
 474     const char      *name;
 475     /**
 476      * A more descriptive name for this codec. May be NULL.
 477      */
 478     const char *long_name;
 479     /**
 480      * Codec properties, a combination of AV_CODEC_PROP_* flags.
 481      */
 482     int             props;
 483 } AVCodecDescriptor;
 484
 485 /**
 486  * Codec uses only intra compression.
 487  * Video codecs only.
 488  */
 489 #define AV_CODEC_PROP_INTRA_ONLY    (1 << 0)
 490 /**
 491  * Codec supports lossy compression. Audio and video codecs only.
 492  * @note a codec may support both lossy and lossless
 493  * compression modes
 494  */
 495 #define AV_CODEC_PROP_LOSSY         (1 << 1)
 496 /**
 497  * Codec supports lossless compression. Audio and video codecs only.
 498  */
 499 #define AV_CODEC_PROP_LOSSLESS      (1 << 2)
 500
 501 /**
 502  * @ingroup lavc_decoding
 503  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
 504  * This is mainly needed because some optimized bitstream readers read
 505  * 32 or 64 bit at once and could read over the end.<br>
 506  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
 507  * MPEG bitstreams could cause overread and segfault.
 508  */
 509 #define FF_INPUT_BUFFER_PADDING_SIZE 8
 510
 511 /**
 512  * @ingroup lavc_encoding
 513  * minimum encoding buffer size
 514  * Used to avoid some checks during header writing.
 515  */
 516 #define FF_MIN_BUFFER_SIZE 16384
 517
 518
 519 /**
 520  * @ingroup lavc_encoding
 521  * motion estimation type.
 522  */
 523 enum Motion_Est_ID {
 524     ME_ZERO = 1,    ///< no search, that is use 0,0 vector whenever one is needed
 525     ME_FULL,
 526     ME_LOG,
 527     ME_PHODS,
 528     ME_EPZS,        ///< enhanced predictive zonal search
 529     ME_X1,          ///< reserved for experiments
 530     ME_HEX,         ///< hexagon based search
 531     ME_UMH,         ///< uneven multi-hexagon search
 532     ME_TESA,        ///< transformed exhaustive search algorithm
 533 };
 534
 535 /**
 536  * @ingroup lavc_decoding
 537  */
 538 enum AVDiscard{
 539     /* We leave some space between them for extensions (drop some
 540      * keyframes for intra-only or drop just some bidir frames). */
 541     AVDISCARD_NONE    =-16, ///< discard nothing
 542     AVDISCARD_DEFAULT =  0, ///< discard useless packets like 0 size packets in avi
 543     AVDISCARD_NONREF  =  8, ///< discard all non reference
 544     AVDISCARD_BIDIR   = 16, ///< discard all bidirectional frames
 545     AVDISCARD_NONKEY  = 32, ///< discard all frames except keyframes
 546     AVDISCARD_ALL     = 48, ///< discard all
 547 };
 548
 549 enum AVColorPrimaries{
 550     AVCOL_PRI_BT709       = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
 551     AVCOL_PRI_UNSPECIFIED = 2,
 552     AVCOL_PRI_BT470M      = 4,
 553     AVCOL_PRI_BT470BG     = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
 554     AVCOL_PRI_SMPTE170M   = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
 555     AVCOL_PRI_SMPTE240M   = 7, ///< functionally identical to above
 556     AVCOL_PRI_FILM        = 8,
 557     AVCOL_PRI_BT2020      = 9, ///< ITU-R BT2020
 558     AVCOL_PRI_NB             , ///< Not part of ABI
 559 };
 560
 561 enum AVColorTransferCharacteristic{
 562     AVCOL_TRC_BT709        =  1, ///< also ITU-R BT1361
 563     AVCOL_TRC_UNSPECIFIED  =  2,
 564     AVCOL_TRC_GAMMA22      =  4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
 565     AVCOL_TRC_GAMMA28      =  5, ///< also ITU-R BT470BG
 566     AVCOL_TRC_SMPTE170M    =  6, ///< also ITU-R BT601-6 525 or 625 / ITU-R BT1358 525 or 625 / ITU-R BT1700 NTSC
 567     AVCOL_TRC_SMPTE240M    =  7,
 568     AVCOL_TRC_LINEAR       =  8, ///< "Linear transfer characteristics"
 569     AVCOL_TRC_LOG          =  9, ///< "Logarithmic transfer characteristic (100:1 range)"
 570     AVCOL_TRC_LOG_SQRT     = 10, ///< "Logarithmic transfer characteristic (100 * Sqrt( 10 ) : 1 range)"
 571     AVCOL_TRC_IEC61966_2_4 = 11, ///< IEC 61966-2-4
 572     AVCOL_TRC_BT1361_ECG   = 12, ///< ITU-R BT1361 Extended Colour Gamut
 573     AVCOL_TRC_IEC61966_2_1 = 13, ///< IEC 61966-2-1 (sRGB or sYCC)
 574     AVCOL_TRC_BT2020_10    = 14, ///< ITU-R BT2020 for 10 bit system
 575     AVCOL_TRC_BT2020_12    = 15, ///< ITU-R BT2020 for 12 bit system
 576     AVCOL_TRC_NB               , ///< Not part of ABI
 577 };
 578
 579 enum AVColorSpace{
 580     AVCOL_SPC_RGB         =  0,
 581     AVCOL_SPC_BT709       =  1, ///< also ITU-R BT1361 / IEC 61966-2-4 xvYCC709 / SMPTE RP177 Annex B
 582     AVCOL_SPC_UNSPECIFIED =  2,
 583     AVCOL_SPC_FCC         =  4,
 584     AVCOL_SPC_BT470BG     =  5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM / IEC 61966-2-4 xvYCC601
 585     AVCOL_SPC_SMPTE170M   =  6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC / functionally identical to above
 586     AVCOL_SPC_SMPTE240M   =  7,
 587     AVCOL_SPC_YCOCG       =  8, ///< Used by Dirac / VC-2 and H.264 FRext, see ITU-T SG16
 588     AVCOL_SPC_BT2020_NCL  =  9, ///< ITU-R BT2020 non-constant luminance system
 589     AVCOL_SPC_BT2020_CL   = 10, ///< ITU-R BT2020 constant luminance system
 590     AVCOL_SPC_NB              , ///< Not part of ABI
 591 };
 592
 593 enum AVColorRange{
 594     AVCOL_RANGE_UNSPECIFIED = 0,
 595     AVCOL_RANGE_MPEG        = 1, ///< the normal 219*2^(n-8) "MPEG" YUV ranges
 596     AVCOL_RANGE_JPEG        = 2, ///< the normal     2^n-1   "JPEG" YUV ranges
 597     AVCOL_RANGE_NB             , ///< Not part of ABI
 598 };
 599
 600 /**
 601  *  X   X      3 4 X      X are luma samples,
 602  *             1 2        1-6 are possible chroma positions
 603  *  X   X      5 6 X      0 is undefined/unknown position
 604  */
 605 enum AVChromaLocation{
 606     AVCHROMA_LOC_UNSPECIFIED = 0,
 607     AVCHROMA_LOC_LEFT        = 1, ///< mpeg2/4, h264 default
 608     AVCHROMA_LOC_CENTER      = 2, ///< mpeg1, jpeg, h263
 609     AVCHROMA_LOC_TOPLEFT     = 3, ///< DV
 610     AVCHROMA_LOC_TOP         = 4,
 611     AVCHROMA_LOC_BOTTOMLEFT  = 5,
 612     AVCHROMA_LOC_BOTTOM      = 6,
 613     AVCHROMA_LOC_NB             , ///< Not part of ABI
 614 };
 615
 616 enum AVAudioServiceType {
 617     AV_AUDIO_SERVICE_TYPE_MAIN              = 0,
 618     AV_AUDIO_SERVICE_TYPE_EFFECTS           = 1,
 619     AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
 620     AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED  = 3,
 621     AV_AUDIO_SERVICE_TYPE_DIALOGUE          = 4,
 622     AV_AUDIO_SERVICE_TYPE_COMMENTARY        = 5,
 623     AV_AUDIO_SERVICE_TYPE_EMERGENCY         = 6,
 624     AV_AUDIO_SERVICE_TYPE_VOICE_OVER        = 7,
 625     AV_AUDIO_SERVICE_TYPE_KARAOKE           = 8,
 626     AV_AUDIO_SERVICE_TYPE_NB                   , ///< Not part of ABI
 627 };
 628
 629 /**
 630  * @ingroup lavc_encoding
 631  */
 632 typedef struct RcOverride{
 633     int start_frame;
 634     int end_frame;
 635     int qscale; // If this is 0 then quality_factor will be used instead.
 636     float quality_factor;
 637 } RcOverride;
 638
 639 #if FF_API_MAX_BFRAMES
 640 /**
 641  * @deprecated there is no libavcodec-wide limit on the number of B-frames
 642  */
 643 #define FF_MAX_B_FRAMES 16
 644 #endif
 645
 646 /* encoding support
 647    These flags can be passed in AVCodecContext.flags before initialization.
 648    Note: Not everything is supported yet.
 649 */
 650
 651 /**
 652  * Allow decoders to produce frames with data planes that are not aligned
 653  * to CPU requirements (e.g. due to cropping).
 654  */
 655 #define CODEC_FLAG_UNALIGNED 0x0001
 656 #define CODEC_FLAG_QSCALE 0x0002  ///< Use fixed qscale.
 657 #define CODEC_FLAG_4MV    0x0004  ///< 4 MV per MB allowed / advanced prediction for H.263.
 658 #define CODEC_FLAG_OUTPUT_CORRUPT 0x0008 ///< Output even those frames that might be corrupted
 659 #define CODEC_FLAG_QPEL   0x0010  ///< Use qpel MC.
 660 #define CODEC_FLAG_GMC    0x0020  ///< Use GMC.
 661 #define CODEC_FLAG_MV0    0x0040  ///< Always try a MB with MV=<0,0>.
 662 /**
 663  * The parent program guarantees that the input for B-frames containing
 664  * streams is not written to for at least s->max_b_frames+1 frames, if
 665  * this is not set the input will be copied.
 666  */
 667 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
 668 #define CODEC_FLAG_PASS1           0x0200   ///< Use internal 2pass ratecontrol in first pass mode.
 669 #define CODEC_FLAG_PASS2           0x0400   ///< Use internal 2pass ratecontrol in second pass mode.
 670 #define CODEC_FLAG_GRAY            0x2000   ///< Only decode/encode grayscale.
 671 #if FF_API_EMU_EDGE
 672 /**
 673  * @deprecated edges are not used/required anymore. I.e. this flag is now always
 674  * set.
 675  */
 676 #define CODEC_FLAG_EMU_EDGE        0x4000
 677 #endif
 678 #define CODEC_FLAG_PSNR            0x8000   ///< error[?] variables will be set during encoding.
 679 #define CODEC_FLAG_TRUNCATED       0x00010000 /** Input bitstream might be truncated at a random
 680                                                   location instead of only at frame boundaries. */
 681 #define CODEC_FLAG_NORMALIZE_AQP  0x00020000 ///< Normalize adaptive quantization.
 682 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
 683 #define CODEC_FLAG_LOW_DELAY      0x00080000 ///< Force low delay.
 684 #define CODEC_FLAG_GLOBAL_HEADER  0x00400000 ///< Place global headers in extradata instead of every keyframe.
 685 #define CODEC_FLAG_BITEXACT       0x00800000 ///< Use only bitexact stuff (except (I)DCT).
 686 /* Fx : Flag for h263+ extra options */
 687 #define CODEC_FLAG_AC_PRED        0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
 688 #define CODEC_FLAG_LOOP_FILTER    0x00000800 ///< loop filter
 689 #define CODEC_FLAG_INTERLACED_ME  0x20000000 ///< interlaced motion estimation
 690 #define CODEC_FLAG_CLOSED_GOP     0x80000000
 691 #define CODEC_FLAG2_FAST          0x00000001 ///< Allow non spec compliant speedup tricks.
 692 #define CODEC_FLAG2_NO_OUTPUT     0x00000004 ///< Skip bitstream encoding.
 693 #define CODEC_FLAG2_LOCAL_HEADER  0x00000008 ///< Place global headers at every keyframe instead of in extradata.
 694 #define CODEC_FLAG2_IGNORE_CROP   0x00010000 ///< Discard cropping information from SPS.
 695
 696 #define CODEC_FLAG2_CHUNKS        0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
 697
 698 /* Unsupported options :
 699  *              Syntax Arithmetic coding (SAC)
 700  *              Reference Picture Selection
 701  *              Independent Segment Decoding */
 702 /* /Fx */
 703 /* codec capabilities */
 704
 705 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
 706 /**
 707  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
 708  * If not set, it might not use get_buffer() at all or use operations that
 709  * assume the buffer was allocated by avcodec_default_get_buffer.
 710  */
 711 #define CODEC_CAP_DR1             0x0002
 712 #define CODEC_CAP_TRUNCATED       0x0008
 713 #if FF_API_XVMC
 714 /* Codec can export data for HW decoding (XvMC). */
 715 #define CODEC_CAP_HWACCEL         0x0010
 716 #endif /* FF_API_XVMC */
 717 /**
 718  * Encoder or decoder requires flushing with NULL input at the end in order to
 719  * give the complete and correct output.
 720  *
 721  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
 722  *       with NULL data. The user can still send NULL data to the public encode
 723  *       or decode function, but libavcodec will not pass it along to the codec
 724  *       unless this flag is set.
 725  *
 726  * Decoders:
 727  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
 728  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
 729  * returns frames.
 730  *
 731  * Encoders:
 732  * The encoder needs to be fed with NULL data at the end of encoding until the
 733  * encoder no longer returns data.
 734  *
 735  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
 736  *       flag also means that the encoder must set the pts and duration for
 737  *       each output packet. If this flag is not set, the pts and duration will
 738  *       be determined by libavcodec from the input frame.
 739  */
 740 #define CODEC_CAP_DELAY           0x0020
 741 /**
 742  * Codec can be fed a final frame with a smaller size.
 743  * This can be used to prevent truncation of the last audio samples.
 744  */
 745 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
 746 #if FF_API_CAP_VDPAU
 747 /**
 748  * Codec can export data for HW decoding (VDPAU).
 749  */
 750 #define CODEC_CAP_HWACCEL_VDPAU    0x0080
 751 #endif
 752 /**
 753  * Codec can output multiple frames per AVPacket
 754  * Normally demuxers return one frame at a time, demuxers which do not do
 755  * are connected to a parser to split what they return into proper frames.
 756  * This flag is reserved to the very rare category of codecs which have a
 757  * bitstream that cannot be split into frames without timeconsuming
 758  * operations like full decoding. Demuxers carring such bitstreams thus
 759  * may return multiple frames in a packet. This has many disadvantages like
 760  * prohibiting stream copy in many cases thus it should only be considered
 761  * as a last resort.
 762  */
 763 #define CODEC_CAP_SUBFRAMES        0x0100
 764 /**
 765  * Codec is experimental and is thus avoided in favor of non experimental
 766  * encoders
 767  */
 768 #define CODEC_CAP_EXPERIMENTAL     0x0200
 769 /**
 770  * Codec should fill in channel configuration and samplerate instead of container
 771  */
 772 #define CODEC_CAP_CHANNEL_CONF     0x0400
 773 #if FF_API_NEG_LINESIZES
 774 /**
 775  * @deprecated no codecs use this capability
 776  */
 777 #define CODEC_CAP_NEG_LINESIZES    0x0800
 778 #endif
 779 /**
 780  * Codec supports frame-level multithreading.
 781  */
 782 #define CODEC_CAP_FRAME_THREADS    0x1000
 783 /**
 784  * Codec supports slice-based (or partition-based) multithreading.
 785  */
 786 #define CODEC_CAP_SLICE_THREADS    0x2000
 787 /**
 788  * Codec supports changed parameters at any point.
 789  */
 790 #define CODEC_CAP_PARAM_CHANGE     0x4000
 791 /**
 792  * Codec supports avctx->thread_count == 0 (auto).
 793  */
 794 #define CODEC_CAP_AUTO_THREADS     0x8000
 795 /**
 796  * Audio encoder supports receiving a different number of samples in each call.
 797  */
 798 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
 799
 800 #if FF_API_MB_TYPE
 801 //The following defines may change, don't expect compatibility if you use them.
 802 #define MB_TYPE_INTRA4x4   0x0001
 803 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
 804 #define MB_TYPE_INTRA_PCM  0x0004 //FIXME H.264-specific
 805 #define MB_TYPE_16x16      0x0008
 806 #define MB_TYPE_16x8       0x0010
 807 #define MB_TYPE_8x16       0x0020
 808 #define MB_TYPE_8x8        0x0040
 809 #define MB_TYPE_INTERLACED 0x0080
 810 #define MB_TYPE_DIRECT2    0x0100 //FIXME
 811 #define MB_TYPE_ACPRED     0x0200
 812 #define MB_TYPE_GMC        0x0400
 813 #define MB_TYPE_SKIP       0x0800
 814 #define MB_TYPE_P0L0       0x1000
 815 #define MB_TYPE_P1L0       0x2000
 816 #define MB_TYPE_P0L1       0x4000
 817 #define MB_TYPE_P1L1       0x8000
 818 #define MB_TYPE_L0         (MB_TYPE_P0L0 | MB_TYPE_P1L0)
 819 #define MB_TYPE_L1         (MB_TYPE_P0L1 | MB_TYPE_P1L1)
 820 #define MB_TYPE_L0L1       (MB_TYPE_L0   | MB_TYPE_L1)
 821 #define MB_TYPE_QUANT      0x00010000
 822 #define MB_TYPE_CBP        0x00020000
 823 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
 824 #endif
 825
 826 /**
 827  * Pan Scan area.
 828  * This specifies the area which should be displayed.
 829  * Note there may be multiple such areas for one frame.
 830  */
 831 typedef struct AVPanScan{
 832     /**
 833      * id
 834      * - encoding: Set by user.
 835      * - decoding: Set by libavcodec.
 836      */
 837     int id;
 838
 839     /**
 840      * width and height in 1/16 pel
 841      * - encoding: Set by user.
 842      * - decoding: Set by libavcodec.
 843      */
 844     int width;
 845     int height;
 846
 847     /**
 848      * position of the top left corner in 1/16 pel for up to 3 fields/frames
 849      * - encoding: Set by user.
 850      * - decoding: Set by libavcodec.
 851      */
 852     int16_t position[3][2];
 853 }AVPanScan;
 854
 855 #if FF_API_QSCALE_TYPE
 856 #define FF_QSCALE_TYPE_MPEG1 0
 857 #define FF_QSCALE_TYPE_MPEG2 1
 858 #define FF_QSCALE_TYPE_H264  2
 859 #define FF_QSCALE_TYPE_VP56  3
 860 #endif
 861
 862 #if FF_API_GET_BUFFER
 863 #define FF_BUFFER_TYPE_INTERNAL 1
 864 #define FF_BUFFER_TYPE_USER     2 ///< direct rendering buffers (image is (de)allocated by user)
 865 #define FF_BUFFER_TYPE_SHARED   4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
 866 #define FF_BUFFER_TYPE_COPY     8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
 867
 868 #define FF_BUFFER_HINTS_VALID    0x01 // Buffer hints value is meaningful (if 0 ignore).
 869 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
 870 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
 871 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
 872 #endif
 873
 874 /**
 875  * The decoder will keep a reference to the frame and may reuse it later.
 876  */
 877 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
 878
 879 /**
 880  * @defgroup lavc_packet AVPacket
 881  *
 882  * Types and functions for working with AVPacket.
 883  * @{
 884  */
 885 enum AVPacketSideDataType {
 886     AV_PKT_DATA_PALETTE,
 887     AV_PKT_DATA_NEW_EXTRADATA,
 888
 889     /**
 890      * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
 891      * @code
 892      * u32le param_flags
 893      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
 894      *     s32le channel_count
 895      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
 896      *     u64le channel_layout
 897      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
 898      *     s32le sample_rate
 899      * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
 900      *     s32le width
 901      *     s32le height
 902      * @endcode
 903      */
 904     AV_PKT_DATA_PARAM_CHANGE,
 905
 906     /**
 907      * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
 908      * structures with info about macroblocks relevant to splitting the
 909      * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
 910      * That is, it does not necessarily contain info about all macroblocks,
 911      * as long as the distance between macroblocks in the info is smaller
 912      * than the target payload size.
 913      * Each MB info structure is 12 bytes, and is laid out as follows:
 914      * @code
 915      * u32le bit offset from the start of the packet
 916      * u8    current quantizer at the start of the macroblock
 917      * u8    GOB number
 918      * u16le macroblock address within the GOB
 919      * u8    horizontal MV predictor
 920      * u8    vertical MV predictor
 921      * u8    horizontal MV predictor for block number 3
 922      * u8    vertical MV predictor for block number 3
 923      * @endcode
 924      */
 925     AV_PKT_DATA_H263_MB_INFO,
 926 };
 927
 928 /**
 929  * This structure stores compressed data. It is typically exported by demuxers
 930  * and then passed as input to decoders, or received as output from encoders and
 931  * then passed to muxers.
 932  *
 933  * For video, it should typically contain one compressed frame. For audio it may
 934  * contain several compressed frames.
 935  *
 936  * AVPacket is one of the few structs in Libav, whose size is a part of public
 937  * ABI. Thus it may be allocated on stack and no new fields can be added to it
 938  * without libavcodec and libavformat major bump.
 939  *
 940  * The semantics of data ownership depends on the buf or destruct (deprecated)
 941  * fields. If either is set, the packet data is dynamically allocated and is
 942  * valid indefinitely until av_free_packet() is called (which in turn calls
 943  * av_buffer_unref()/the destruct callback to free the data). If neither is set,
 944  * the packet data is typically backed by some static buffer somewhere and is
 945  * only valid for a limited time (e.g. until the next read call when demuxing).
 946  *
 947  * The side data is always allocated with av_malloc() and is freed in
 948  * av_free_packet().
 949  */
 950 typedef struct AVPacket {
 951     /**
 952      * A reference to the reference-counted buffer where the packet data is
 953      * stored.
 954      * May be NULL, then the packet data is not reference-counted.
 955      */
 956     AVBufferRef *buf;
 957     /**
 958      * Presentation timestamp in AVStream->time_base units; the time at which
 959      * the decompressed packet will be presented to the user.
 960      * Can be AV_NOPTS_VALUE if it is not stored in the file.
 961      * pts MUST be larger or equal to dts as presentation cannot happen before
 962      * decompression, unless one wants to view hex dumps. Some formats misuse
 963      * the terms dts and pts/cts to mean something different. Such timestamps
 964      * must be converted to true pts/dts before they are stored in AVPacket.
 965      */
 966     int64_t pts;
 967     /**
 968      * Decompression timestamp in AVStream->time_base units; the time at which
 969      * the packet is decompressed.
 970      * Can be AV_NOPTS_VALUE if it is not stored in the file.
 971      */
 972     int64_t dts;
 973     uint8_t *data;
 974     int   size;
 975     int   stream_index;
 976     /**
 977      * A combination of AV_PKT_FLAG values
 978      */
 979     int   flags;
 980     /**
 981      * Additional packet data that can be provided by the container.
 982      * Packet can contain several types of side information.
 983      */
 984     struct {
 985         uint8_t *data;
 986         int      size;
 987         enum AVPacketSideDataType type;
 988     } *side_data;
 989     int side_data_elems;
 990
 991     /**
 992      * Duration of this packet in AVStream->time_base units, 0 if unknown.
 993      * Equals next_pts - this_pts in presentation order.
 994      */
 995     int   duration;
 996 #if FF_API_DESTRUCT_PACKET
 997     attribute_deprecated
 998     void  (*destruct)(struct AVPacket *);
 999     attribute_deprecated
1000     void  *priv;
1001 #endif
1002     int64_t pos;                            ///< byte position in stream, -1 if unknown
1003
1004     /**
1005      * Time difference in AVStream->time_base units from the pts of this
1006      * packet to the point at which the output from the decoder has converged
1007      * independent from the availability of previous frames. That is, the
1008      * frames are virtually identical no matter if decoding started from
1009      * the very first frame or from this keyframe.
1010      * Is AV_NOPTS_VALUE if unknown.
1011      * This field is not the display duration of the current packet.
1012      * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
1013      * set.
1014      *
1015      * The purpose of this field is to allow seeking in streams that have no
1016      * keyframes in the conventional sense. It corresponds to the
1017      * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1018      * essential for some types of subtitle streams to ensure that all
1019      * subtitles are correctly displayed after seeking.
1020      */
1021     int64_t convergence_duration;
1022 } AVPacket;
1023 #define AV_PKT_FLAG_KEY     0x0001 ///< The packet contains a keyframe
1024 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1025
1026 enum AVSideDataParamChangeFlags {
1027     AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT  = 0x0001,
1028     AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1029     AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE    = 0x0004,
1030     AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS     = 0x0008,
1031 };
1032 /**
1033  * @}
1034  */
1035
1036 struct AVCodecInternal;
1037
1038 enum AVFieldOrder {
1039     AV_FIELD_UNKNOWN,
1040     AV_FIELD_PROGRESSIVE,
1041     AV_FIELD_TT,          //< Top coded_first, top displayed first
1042     AV_FIELD_BB,          //< Bottom coded first, bottom displayed first
1043     AV_FIELD_TB,          //< Top coded first, bottom displayed first
1044     AV_FIELD_BT,          //< Bottom coded first, top displayed first
1045 };
1046
1047 /**
1048  * main external API structure.
1049  * New fields can be added to the end with minor version bumps.
1050  * Removal, reordering and changes to existing fields require a major
1051  * version bump.
1052  * sizeof(AVCodecContext) must not be used outside libav*.
1053  */
1054 typedef struct AVCodecContext {
1055     /**
1056      * information on struct for av_log
1057      * - set by avcodec_alloc_context3
1058      */
1059     const AVClass *av_class;
1060     int log_level_offset;
1061
1062     enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1063     const struct AVCodec  *codec;
1064     char             codec_name[32];
1065     enum AVCodecID     codec_id; /* see AV_CODEC_ID_xxx */
1066
1067     /**
1068      * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1069      * This is used to work around some encoder bugs.
1070      * A demuxer should set this to what is stored in the field used to identify the codec.
1071      * If there are multiple such fields in a container then the demuxer should choose the one
1072      * which maximizes the information about the used codec.
1073      * If the codec tag field in a container is larger than 32 bits then the demuxer should
1074      * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1075      * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1076      * first.
1077      * - encoding: Set by user, if not then the default based on codec_id will be used.
1078      * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1079      */
1080     unsigned int codec_tag;
1081
1082     /**
1083      * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1084      * This is used to work around some encoder bugs.
1085      * - encoding: unused
1086      * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1087      */
1088     unsigned int stream_codec_tag;
1089
1090     void *priv_data;
1091
1092     /**
1093      * Private context used for internal data.
1094      *
1095      * Unlike priv_data, this is not codec-specific. It is used in general
1096      * libavcodec functions.
1097      */
1098     struct AVCodecInternal *internal;
1099
1100     /**
1101      * Private data of the user, can be used to carry app specific stuff.
1102      * - encoding: Set by user.
1103      * - decoding: Set by user.
1104      */
1105     void *opaque;
1106
1107     /**
1108      * the average bitrate
1109      * - encoding: Set by user; unused for constant quantizer encoding.
1110      * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1111      */
1112     int bit_rate;
1113
1114     /**
1115      * number of bits the bitstream is allowed to diverge from the reference.
1116      *           the reference can be CBR (for CBR pass1) or VBR (for pass2)
1117      * - encoding: Set by user; unused for constant quantizer encoding.
1118      * - decoding: unused
1119      */
1120     int bit_rate_tolerance;
1121
1122     /**
1123      * Global quality for codecs which cannot change it per frame.
1124      * This should be proportional to MPEG-1/2/4 qscale.
1125      * - encoding: Set by user.
1126      * - decoding: unused
1127      */
1128     int global_quality;
1129
1130     /**
1131      * - encoding: Set by user.
1132      * - decoding: unused
1133      */
1134     int compression_level;
1135 #define FF_COMPRESSION_DEFAULT -1
1136
1137     /**
1138      * CODEC_FLAG_*.
1139      * - encoding: Set by user.
1140      * - decoding: Set by user.
1141      */
1142     int flags;
1143
1144     /**
1145      * CODEC_FLAG2_*
1146      * - encoding: Set by user.
1147      * - decoding: Set by user.
1148      */
1149     int flags2;
1150
1151     /**
1152      * some codecs need / can use extradata like Huffman tables.
1153      * mjpeg: Huffman tables
1154      * rv10: additional flags
1155      * mpeg4: global headers (they can be in the bitstream or here)
1156      * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1157      * than extradata_size to avoid prolems if it is read with the bitstream reader.
1158      * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1159      * - encoding: Set/allocated/freed by libavcodec.
1160      * - decoding: Set/allocated/freed by user.
1161      */
1162     uint8_t *extradata;
1163     int extradata_size;
1164
1165     /**
1166      * This is the fundamental unit of time (in seconds) in terms
1167      * of which frame timestamps are represented. For fixed-fps content,
1168      * timebase should be 1/framerate and timestamp increments should be
1169      * identically 1.
1170      * - encoding: MUST be set by user.
1171      * - decoding: Set by libavcodec.
1172      */
1173     AVRational time_base;
1174
1175     /**
1176      * For some codecs, the time base is closer to the field rate than the frame rate.
1177      * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1178      * if no telecine is used ...
1179      *
1180      * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1181      */
1182     int ticks_per_frame;
1183
1184     /**
1185      * Codec delay.
1186      *
1187      * Video:
1188      *   Number of frames the decoded output will be delayed relative to the
1189      *   encoded input.
1190      *
1191      * Audio:
1192      *   For encoding, this is the number of "priming" samples added to the
1193      *   beginning of the stream. The decoded output will be delayed by this
1194      *   many samples relative to the input to the encoder. Note that this
1195      *   field is purely informational and does not directly affect the pts
1196      *   output by the encoder, which should always be based on the actual
1197      *   presentation time, including any delay.
1198      *   For decoding, this is the number of samples the decoder needs to
1199      *   output before the decoder's output is valid. When seeking, you should
1200      *   start decoding this many samples prior to your desired seek point.
1201      *
1202      * - encoding: Set by libavcodec.
1203      * - decoding: Set by libavcodec.
1204      */
1205     int delay;
1206
1207
1208     /* video only */
1209     /**
1210      * picture width / height.
1211      * - encoding: MUST be set by user.
1212      * - decoding: May be set by the user before opening the decoder if known e.g.
1213      *             from the container. Some decoders will require the dimensions
1214      *             to be set by the caller. During decoding, the decoder may
1215      *             overwrite those values as required.
1216      */
1217     int width, height;
1218
1219     /**
1220      * Bitstream width / height, may be different from width/height e.g. when
1221      * the decoded frame is cropped before being output.
1222      * - encoding: unused
1223      * - decoding: May be set by the user before opening the decoder if known
1224      *             e.g. from the container. During decoding, the decoder may
1225      *             overwrite those values as required.
1226      */
1227     int coded_width, coded_height;
1228
1229 #if FF_API_ASPECT_EXTENDED
1230 #define FF_ASPECT_EXTENDED 15
1231 #endif
1232
1233     /**
1234      * the number of pictures in a group of pictures, or 0 for intra_only
1235      * - encoding: Set by user.
1236      * - decoding: unused
1237      */
1238     int gop_size;
1239
1240     /**
1241      * Pixel format, see AV_PIX_FMT_xxx.
1242      * May be set by the demuxer if known from headers.
1243      * May be overriden by the decoder if it knows better.
1244      * - encoding: Set by user.
1245      * - decoding: Set by user if known, overridden by libavcodec if known
1246      */
1247     enum AVPixelFormat pix_fmt;
1248
1249     /**
1250      * Motion estimation algorithm used for video coding.
1251      * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1252      * 8 (umh), 10 (tesa) [7, 8, 10 are x264 specific]
1253      * - encoding: MUST be set by user.
1254      * - decoding: unused
1255      */
1256     int me_method;
1257
1258     /**
1259      * If non NULL, 'draw_horiz_band' is called by the libavcodec
1260      * decoder to draw a horizontal band. It improves cache usage. Not
1261      * all codecs can do that. You must check the codec capabilities
1262      * beforehand.
1263      * When multithreading is used, it may be called from multiple threads
1264      * at the same time; threads might draw different parts of the same AVFrame,
1265      * or multiple AVFrames, and there is no guarantee that slices will be drawn
1266      * in order.
1267      * The function is also used by hardware acceleration APIs.
1268      * It is called at least once during frame decoding to pass
1269      * the data needed for hardware render.
1270      * In that mode instead of pixel data, AVFrame points to
1271      * a structure specific to the acceleration API. The application
1272      * reads the structure and can change some fields to indicate progress
1273      * or mark state.
1274      * - encoding: unused
1275      * - decoding: Set by user.
1276      * @param height the height of the slice
1277      * @param y the y position of the slice
1278      * @param type 1->top field, 2->bottom field, 3->frame
1279      * @param offset offset into the AVFrame.data from which the slice should be read
1280      */
1281     void (*draw_horiz_band)(struct AVCodecContext *s,
1282                             const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1283                             int y, int type, int height);
1284
1285     /**
1286      * callback to negotiate the pixelFormat
1287      * @param fmt is the list of formats which are supported by the codec,
1288      * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1289      * The first is always the native one.
1290      * @return the chosen format
1291      * - encoding: unused
1292      * - decoding: Set by user, if not set the native format will be chosen.
1293      */
1294     enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1295
1296     /**
1297      * maximum number of B-frames between non-B-frames
1298      * Note: The output will be delayed by max_b_frames+1 relative to the input.
1299      * - encoding: Set by user.
1300      * - decoding: unused
1301      */
1302     int max_b_frames;
1303
1304     /**
1305      * qscale factor between IP and B-frames
1306      * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1307      * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1308      * - encoding: Set by user.
1309      * - decoding: unused
1310      */
1311     float b_quant_factor;
1312
1313     /** obsolete FIXME remove */
1314     int rc_strategy;
1315 #define FF_RC_STRATEGY_XVID 1
1316
1317     int b_frame_strategy;
1318
1319     /**
1320      * qscale offset between IP and B-frames
1321      * - encoding: Set by user.
1322      * - decoding: unused
1323      */
1324     float b_quant_offset;
1325
1326     /**
1327      * Size of the frame reordering buffer in the decoder.
1328      * For MPEG-2 it is 1 IPB or 0 low delay IP.
1329      * - encoding: Set by libavcodec.
1330      * - decoding: Set by libavcodec.
1331      */
1332     int has_b_frames;
1333
1334     /**
1335      * 0-> h263 quant 1-> mpeg quant
1336      * - encoding: Set by user.
1337      * - decoding: unused
1338      */
1339     int mpeg_quant;
1340
1341     /**
1342      * qscale factor between P and I-frames
1343      * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1344      * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1345      * - encoding: Set by user.
1346      * - decoding: unused
1347      */
1348     float i_quant_factor;
1349
1350     /**
1351      * qscale offset between P and I-frames
1352      * - encoding: Set by user.
1353      * - decoding: unused
1354      */
1355     float i_quant_offset;
1356
1357     /**
1358      * luminance masking (0-> disabled)
1359      * - encoding: Set by user.
1360      * - decoding: unused
1361      */
1362     float lumi_masking;
1363
1364     /**
1365      * temporary complexity masking (0-> disabled)
1366      * - encoding: Set by user.
1367      * - decoding: unused
1368      */
1369     float temporal_cplx_masking;
1370
1371     /**
1372      * spatial complexity masking (0-> disabled)
1373      * - encoding: Set by user.
1374      * - decoding: unused
1375      */
1376     float spatial_cplx_masking;
1377
1378     /**
1379      * p block masking (0-> disabled)
1380      * - encoding: Set by user.
1381      * - decoding: unused
1382      */
1383     float p_masking;
1384
1385     /**
1386      * darkness masking (0-> disabled)
1387      * - encoding: Set by user.
1388      * - decoding: unused
1389      */
1390     float dark_masking;
1391
1392     /**
1393      * slice count
1394      * - encoding: Set by libavcodec.
1395      * - decoding: Set by user (or 0).
1396      */
1397     int slice_count;
1398     /**
1399      * prediction method (needed for huffyuv)
1400      * - encoding: Set by user.
1401      * - decoding: unused
1402      */
1403      int prediction_method;
1404 #define FF_PRED_LEFT   0
1405 #define FF_PRED_PLANE  1
1406 #define FF_PRED_MEDIAN 2
1407
1408     /**
1409      * slice offsets in the frame in bytes
1410      * - encoding: Set/allocated by libavcodec.
1411      * - decoding: Set/allocated by user (or NULL).
1412      */
1413     int *slice_offset;
1414
1415     /**
1416      * sample aspect ratio (0 if unknown)
1417      * That is the width of a pixel divided by the height of the pixel.
1418      * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1419      * - encoding: Set by user.
1420      * - decoding: Set by libavcodec.
1421      */
1422     AVRational sample_aspect_ratio;
1423
1424     /**
1425      * motion estimation comparison function
1426      * - encoding: Set by user.
1427      * - decoding: unused
1428      */
1429     int me_cmp;
1430     /**
1431      * subpixel motion estimation comparison function
1432      * - encoding: Set by user.
1433      * - decoding: unused
1434      */
1435     int me_sub_cmp;
1436     /**
1437      * macroblock comparison function (not supported yet)
1438      * - encoding: Set by user.
1439      * - decoding: unused
1440      */
1441     int mb_cmp;
1442     /**
1443      * interlaced DCT comparison function
1444      * - encoding: Set by user.
1445      * - decoding: unused
1446      */
1447     int ildct_cmp;
1448 #define FF_CMP_SAD    0
1449 #define FF_CMP_SSE    1
1450 #define FF_CMP_SATD   2
1451 #define FF_CMP_DCT    3
1452 #define FF_CMP_PSNR   4
1453 #define FF_CMP_BIT    5
1454 #define FF_CMP_RD     6
1455 #define FF_CMP_ZERO   7
1456 #define FF_CMP_VSAD   8
1457 #define FF_CMP_VSSE   9
1458 #define FF_CMP_NSSE   10
1459 #define FF_CMP_DCTMAX 13
1460 #define FF_CMP_DCT264 14
1461 #define FF_CMP_CHROMA 256
1462
1463     /**
1464      * ME diamond size & shape
1465      * - encoding: Set by user.
1466      * - decoding: unused
1467      */
1468     int dia_size;
1469
1470     /**
1471      * amount of previous MV predictors (2a+1 x 2a+1 square)
1472      * - encoding: Set by user.
1473      * - decoding: unused
1474      */
1475     int last_predictor_count;
1476
1477     /**
1478      * prepass for motion estimation
1479      * - encoding: Set by user.
1480      * - decoding: unused
1481      */
1482     int pre_me;
1483
1484     /**
1485      * motion estimation prepass comparison function
1486      * - encoding: Set by user.
1487      * - decoding: unused
1488      */
1489     int me_pre_cmp;
1490
1491     /**
1492      * ME prepass diamond size & shape
1493      * - encoding: Set by user.
1494      * - decoding: unused
1495      */
1496     int pre_dia_size;
1497
1498     /**
1499      * subpel ME quality
1500      * - encoding: Set by user.
1501      * - decoding: unused
1502      */
1503     int me_subpel_quality;
1504
1505     /**
1506      * DTG active format information (additional aspect ratio
1507      * information only used in DVB MPEG-2 transport streams)
1508      * 0 if not set.
1509      *
1510      * - encoding: unused
1511      * - decoding: Set by decoder.
1512      */
1513     int dtg_active_format;
1514 #define FF_DTG_AFD_SAME         8
1515 #define FF_DTG_AFD_4_3          9
1516 #define FF_DTG_AFD_16_9         10
1517 #define FF_DTG_AFD_14_9         11
1518 #define FF_DTG_AFD_4_3_SP_14_9  13
1519 #define FF_DTG_AFD_16_9_SP_14_9 14
1520 #define FF_DTG_AFD_SP_4_3       15
1521
1522     /**
1523      * maximum motion estimation search range in subpel units
1524      * If 0 then no limit.
1525      *
1526      * - encoding: Set by user.
1527      * - decoding: unused
1528      */
1529     int me_range;
1530
1531     /**
1532      * intra quantizer bias
1533      * - encoding: Set by user.
1534      * - decoding: unused
1535      */
1536     int intra_quant_bias;
1537 #define FF_DEFAULT_QUANT_BIAS 999999
1538
1539     /**
1540      * inter quantizer bias
1541      * - encoding: Set by user.
1542      * - decoding: unused
1543      */
1544     int inter_quant_bias;
1545
1546     /**
1547      * slice flags
1548      * - encoding: unused
1549      * - decoding: Set by user.
1550      */
1551     int slice_flags;
1552 #define SLICE_FLAG_CODED_ORDER    0x0001 ///< draw_horiz_band() is called in coded order instead of display
1553 #define SLICE_FLAG_ALLOW_FIELD    0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1554 #define SLICE_FLAG_ALLOW_PLANE    0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1555
1556 #if FF_API_XVMC
1557     /**
1558      * XVideo Motion Acceleration
1559      * - encoding: forbidden
1560      * - decoding: set by decoder
1561      * @deprecated XvMC support is slated for removal.
1562      */
1563     attribute_deprecated int xvmc_acceleration;
1564 #endif /* FF_API_XVMC */
1565
1566     /**
1567      * macroblock decision mode
1568      * - encoding: Set by user.
1569      * - decoding: unused
1570      */
1571     int mb_decision;
1572 #define FF_MB_DECISION_SIMPLE 0        ///< uses mb_cmp
1573 #define FF_MB_DECISION_BITS   1        ///< chooses the one which needs the fewest bits
1574 #define FF_MB_DECISION_RD     2        ///< rate distortion
1575
1576     /**
1577      * custom intra quantization matrix
1578      * - encoding: Set by user, can be NULL.
1579      * - decoding: Set by libavcodec.
1580      */
1581     uint16_t *intra_matrix;
1582
1583     /**
1584      * custom inter quantization matrix
1585      * - encoding: Set by user, can be NULL.
1586      * - decoding: Set by libavcodec.
1587      */
1588     uint16_t *inter_matrix;
1589
1590     /**
1591      * scene change detection threshold
1592      * 0 is default, larger means fewer detected scene changes.
1593      * - encoding: Set by user.
1594      * - decoding: unused
1595      */
1596     int scenechange_threshold;
1597
1598     /**
1599      * noise reduction strength
1600      * - encoding: Set by user.
1601      * - decoding: unused
1602      */
1603     int noise_reduction;
1604
1605     /**
1606      * Motion estimation threshold below which no motion estimation is
1607      * performed, but instead the user specified motion vectors are used.
1608      *
1609      * - encoding: Set by user.
1610      * - decoding: unused
1611      */
1612     int me_threshold;
1613
1614     /**
1615      * Macroblock threshold below which the user specified macroblock types will be used.
1616      * - encoding: Set by user.
1617      * - decoding: unused
1618      */
1619     int mb_threshold;
1620
1621     /**
1622      * precision of the intra DC coefficient - 8
1623      * - encoding: Set by user.
1624      * - decoding: unused
1625      */
1626     int intra_dc_precision;
1627
1628     /**
1629      * Number of macroblock rows at the top which are skipped.
1630      * - encoding: unused
1631      * - decoding: Set by user.
1632      */
1633     int skip_top;
1634
1635     /**
1636      * Number of macroblock rows at the bottom which are skipped.
1637      * - encoding: unused
1638      * - decoding: Set by user.
1639      */
1640     int skip_bottom;
1641
1642     /**
1643      * Border processing masking, raises the quantizer for mbs on the borders
1644      * of the picture.
1645      * - encoding: Set by user.
1646      * - decoding: unused
1647      */
1648     float border_masking;
1649
1650     /**
1651      * minimum MB lagrange multipler
1652      * - encoding: Set by user.
1653      * - decoding: unused
1654      */
1655     int mb_lmin;
1656
1657     /**
1658      * maximum MB lagrange multipler
1659      * - encoding: Set by user.
1660      * - decoding: unused
1661      */
1662     int mb_lmax;
1663
1664     /**
1665      *
1666      * - encoding: Set by user.
1667      * - decoding: unused
1668      */
1669     int me_penalty_compensation;
1670
1671     /**
1672      *
1673      * - encoding: Set by user.
1674      * - decoding: unused
1675      */
1676     int bidir_refine;
1677
1678     /**
1679      *
1680      * - encoding: Set by user.
1681      * - decoding: unused
1682      */
1683     int brd_scale;
1684
1685     /**
1686      * minimum GOP size
1687      * - encoding: Set by user.
1688      * - decoding: unused
1689      */
1690     int keyint_min;
1691
1692     /**
1693      * number of reference frames
1694      * - encoding: Set by user.
1695      * - decoding: Set by lavc.
1696      */
1697     int refs;
1698
1699     /**
1700      * chroma qp offset from luma
1701      * - encoding: Set by user.
1702      * - decoding: unused
1703      */
1704     int chromaoffset;
1705
1706     /**
1707      * Multiplied by qscale for each frame and added to scene_change_score.
1708      * - encoding: Set by user.
1709      * - decoding: unused
1710      */
1711     int scenechange_factor;
1712
1713     /**
1714      *
1715      * Note: Value depends upon the compare function used for fullpel ME.
1716      * - encoding: Set by user.
1717      * - decoding: unused
1718      */
1719     int mv0_threshold;
1720
1721     /**
1722      * Adjust sensitivity of b_frame_strategy 1.
1723      * - encoding: Set by user.
1724      * - decoding: unused
1725      */
1726     int b_sensitivity;
1727
1728     /**
1729      * Chromaticity coordinates of the source primaries.
1730      * - encoding: Set by user
1731      * - decoding: Set by libavcodec
1732      */
1733     enum AVColorPrimaries color_primaries;
1734
1735     /**
1736      * Color Transfer Characteristic.
1737      * - encoding: Set by user
1738      * - decoding: Set by libavcodec
1739      */
1740     enum AVColorTransferCharacteristic color_trc;
1741
1742     /**
1743      * YUV colorspace type.
1744      * - encoding: Set by user
1745      * - decoding: Set by libavcodec
1746      */
1747     enum AVColorSpace colorspace;
1748
1749     /**
1750      * MPEG vs JPEG YUV range.
1751      * - encoding: Set by user
1752      * - decoding: Set by libavcodec
1753      */
1754     enum AVColorRange color_range;
1755
1756     /**
1757      * This defines the location of chroma samples.
1758      * - encoding: Set by user
1759      * - decoding: Set by libavcodec
1760      */
1761     enum AVChromaLocation chroma_sample_location;
1762
1763     /**
1764      * Number of slices.
1765      * Indicates number of picture subdivisions. Used for parallelized
1766      * decoding.
1767      * - encoding: Set by user
1768      * - decoding: unused
1769      */
1770     int slices;
1771
1772     /** Field order
1773      * - encoding: set by libavcodec
1774      * - decoding: Set by libavcodec
1775      */
1776     enum AVFieldOrder field_order;
1777
1778     /* audio only */
1779     int sample_rate; ///< samples per second
1780     int channels;    ///< number of audio channels
1781
1782     /**
1783      * audio sample format
1784      * - encoding: Set by user.
1785      * - decoding: Set by libavcodec.
1786      */
1787     enum AVSampleFormat sample_fmt;  ///< sample format
1788
1789     /* The following data should not be initialized. */
1790     /**
1791      * Number of samples per channel in an audio frame.
1792      *
1793      * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1794      *   except the last must contain exactly frame_size samples per channel.
1795      *   May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1796      *   frame size is not restricted.
1797      * - decoding: may be set by some decoders to indicate constant frame size
1798      */
1799     int frame_size;
1800
1801     /**
1802      * Frame counter, set by libavcodec.
1803      *
1804      * - decoding: total number of frames returned from the decoder so far.
1805      * - encoding: total number of frames passed to the encoder so far.
1806      *
1807      *   @note the counter is not incremented if encoding/decoding resulted in
1808      *   an error.
1809      */
1810     int frame_number;
1811
1812     /**
1813      * number of bytes per packet if constant and known or 0
1814      * Used by some WAV based audio codecs.
1815      */
1816     int block_align;
1817
1818     /**
1819      * Audio cutoff bandwidth (0 means "automatic")
1820      * - encoding: Set by user.
1821      * - decoding: unused
1822      */
1823     int cutoff;
1824
1825 #if FF_API_REQUEST_CHANNELS
1826     /**
1827      * Decoder should decode to this many channels if it can (0 for default)
1828      * - encoding: unused
1829      * - decoding: Set by user.
1830      * @deprecated Deprecated in favor of request_channel_layout.
1831      */
1832     attribute_deprecated int request_channels;
1833 #endif
1834
1835     /**
1836      * Audio channel layout.
1837      * - encoding: set by user.
1838      * - decoding: set by libavcodec.
1839      */
1840     uint64_t channel_layout;
1841
1842     /**
1843      * Request decoder to use this channel layout if it can (0 for default)
1844      * - encoding: unused
1845      * - decoding: Set by user.
1846      */
1847     uint64_t request_channel_layout;
1848
1849     /**
1850      * Type of service that the audio stream conveys.
1851      * - encoding: Set by user.
1852      * - decoding: Set by libavcodec.
1853      */
1854     enum AVAudioServiceType audio_service_type;
1855
1856     /**
1857      * Used to request a sample format from the decoder.
1858      * - encoding: unused.
1859      * - decoding: Set by user.
1860      */
1861     enum AVSampleFormat request_sample_fmt;
1862
1863 #if FF_API_GET_BUFFER
1864     /**
1865      * Called at the beginning of each frame to get a buffer for it.
1866      *
1867      * The function will set AVFrame.data[], AVFrame.linesize[].
1868      * AVFrame.extended_data[] must also be set, but it should be the same as
1869      * AVFrame.data[] except for planar audio with more channels than can fit
1870      * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
1871      * many data pointers as it can hold.
1872      *
1873      * if CODEC_CAP_DR1 is not set then get_buffer() must call
1874      * avcodec_default_get_buffer() instead of providing buffers allocated by
1875      * some other means.
1876      *
1877      * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
1878      * need it. avcodec_default_get_buffer() aligns the output buffer properly,
1879      * but if get_buffer() is overridden then alignment considerations should
1880      * be taken into account.
1881      *
1882      * @see avcodec_default_get_buffer()
1883      *
1884      * Video:
1885      *
1886      * If pic.reference is set then the frame will be read later by libavcodec.
1887      * avcodec_align_dimensions2() should be used to find the required width and
1888      * height, as they normally need to be rounded up to the next multiple of 16.
1889      *
1890      * If frame multithreading is used and thread_safe_callbacks is set,
1891      * it may be called from a different thread, but not from more than one at
1892      * once. Does not need to be reentrant.
1893      *
1894      * @see release_buffer(), reget_buffer()
1895      * @see avcodec_align_dimensions2()
1896      *
1897      * Audio:
1898      *
1899      * Decoders request a buffer of a particular size by setting
1900      * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
1901      * however, utilize only part of the buffer by setting AVFrame.nb_samples
1902      * to a smaller value in the output frame.
1903      *
1904      * Decoders cannot use the buffer after returning from
1905      * avcodec_decode_audio4(), so they will not call release_buffer(), as it
1906      * is assumed to be released immediately upon return. In some rare cases,
1907      * a decoder may need to call get_buffer() more than once in a single
1908      * call to avcodec_decode_audio4(). In that case, when get_buffer() is
1909      * called again after it has already been called once, the previously
1910      * acquired buffer is assumed to be released at that time and may not be
1911      * reused by the decoder.
1912      *
1913      * As a convenience, av_samples_get_buffer_size() and
1914      * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
1915      * functions to find the required data size and to fill data pointers and
1916      * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1917      * since all planes must be the same size.
1918      *
1919      * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1920      *
1921      * - encoding: unused
1922      * - decoding: Set by libavcodec, user can override.
1923      *
1924      * @deprecated use get_buffer2()
1925      */
1926     attribute_deprecated
1927     int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
1928
1929     /**
1930      * Called to release buffers which were allocated with get_buffer.
1931      * A released buffer can be reused in get_buffer().
1932      * pic.data[*] must be set to NULL.
1933      * May be called from a different thread if frame multithreading is used,
1934      * but not by more than one thread at once, so does not need to be reentrant.
1935      * - encoding: unused
1936      * - decoding: Set by libavcodec, user can override.
1937      *
1938      * @deprecated custom freeing callbacks should be set from get_buffer2()
1939      */
1940     attribute_deprecated
1941     void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
1942
1943     /**
1944      * Called at the beginning of a frame to get cr buffer for it.
1945      * Buffer type (size, hints) must be the same. libavcodec won't check it.
1946      * libavcodec will pass previous buffer in pic, function should return
1947      * same buffer or new buffer with old frame "painted" into it.
1948      * If pic.data[0] == NULL must behave like get_buffer().
1949      * if CODEC_CAP_DR1 is not set then reget_buffer() must call
1950      * avcodec_default_reget_buffer() instead of providing buffers allocated by
1951      * some other means.
1952      * - encoding: unused
1953      * - decoding: Set by libavcodec, user can override.
1954      */
1955     attribute_deprecated
1956     int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
1957 #endif
1958
1959     /**
1960      * This callback is called at the beginning of each frame to get data
1961      * buffer(s) for it. There may be one contiguous buffer for all the data or
1962      * there may be a buffer per each data plane or anything in between. What
1963      * this means is, you may set however many entries in buf[] you feel necessary.
1964      * Each buffer must be reference-counted using the AVBuffer API (see description
1965      * of buf[] below).
1966      *
1967      * The following fields will be set in the frame before this callback is
1968      * called:
1969      * - format
1970      * - width, height (video only)
1971      * - sample_rate, channel_layout, nb_samples (audio only)
1972      * Their values may differ from the corresponding values in
1973      * AVCodecContext. This callback must use the frame values, not the codec
1974      * context values, to calculate the required buffer size.
1975      *
1976      * This callback must fill the following fields in the frame:
1977      * - data[]
1978      * - linesize[]
1979      * - extended_data:
1980      *   * if the data is planar audio with more than 8 channels, then this
1981      *     callback must allocate and fill extended_data to contain all pointers
1982      *     to all data planes. data[] must hold as many pointers as it can.
1983      *     extended_data must be allocated with av_malloc() and will be freed in
1984      *     av_frame_unref().
1985      *   * otherwise exended_data must point to data
1986      * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1987      *   the frame's data and extended_data pointers must be contained in these. That
1988      *   is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1989      *   AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1990      *   and av_buffer_ref().
1991      * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1992      *   this callback and filled with the extra buffers if there are more
1993      *   buffers than buf[] can hold. extended_buf will be freed in
1994      *   av_frame_unref().
1995      *
1996      * If CODEC_CAP_DR1 is not set then get_buffer2() must call
1997      * avcodec_default_get_buffer2() instead of providing buffers allocated by
1998      * some other means.
1999      *
2000      * Each data plane must be aligned to the maximum required by the target
2001      * CPU.
2002      *
2003      * @see avcodec_default_get_buffer2()
2004      *
2005      * Video:
2006      *
2007      * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2008      * (read and/or written to if it is writable) later by libavcodec.
2009      *
2010      * avcodec_align_dimensions2() should be used to find the required width and
2011      * height, as they normally need to be rounded up to the next multiple of 16.
2012      *
2013      * If frame multithreading is used and thread_safe_callbacks is set,
2014      * this callback may be called from a different thread, but not from more
2015      * than one at once. Does not need to be reentrant.
2016      *
2017      * @see avcodec_align_dimensions2()
2018      *
2019      * Audio:
2020      *
2021      * Decoders request a buffer of a particular size by setting
2022      * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2023      * however, utilize only part of the buffer by setting AVFrame.nb_samples
2024      * to a smaller value in the output frame.
2025      *
2026      * As a convenience, av_samples_get_buffer_size() and
2027      * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2028      * functions to find the required data size and to fill data pointers and
2029      * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2030      * since all planes must be the same size.
2031      *
2032      * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2033      *
2034      * - encoding: unused
2035      * - decoding: Set by libavcodec, user can override.
2036      */
2037     int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2038
2039     /**
2040      * If non-zero, the decoded audio and video frames returned from
2041      * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2042      * and are valid indefinitely. The caller must free them with
2043      * av_frame_unref() when they are not needed anymore.
2044      * Otherwise, the decoded frames must not be freed by the caller and are
2045      * only valid until the next decode call.
2046      *
2047      * - encoding: unused
2048      * - decoding: set by the caller before avcodec_open2().
2049      */
2050     int refcounted_frames;
2051
2052     /* - encoding parameters */
2053     float qcompress;  ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2054     float qblur;      ///< amount of qscale smoothing over time (0.0-1.0)
2055
2056     /**
2057      * minimum quantizer
2058      * - encoding: Set by user.
2059      * - decoding: unused
2060      */
2061     int qmin;
2062
2063     /**
2064      * maximum quantizer
2065      * - encoding: Set by user.
2066      * - decoding: unused
2067      */
2068     int qmax;
2069
2070     /**
2071      * maximum quantizer difference between frames
2072      * - encoding: Set by user.
2073      * - decoding: unused
2074      */
2075     int max_qdiff;
2076
2077     /**
2078      * ratecontrol qmin qmax limiting method
2079      * 0-> clipping, 1-> use a nice continuous function to limit qscale wthin qmin/qmax.
2080      * - encoding: Set by user.
2081      * - decoding: unused
2082      */
2083     float rc_qsquish;
2084
2085     float rc_qmod_amp;
2086     int rc_qmod_freq;
2087
2088     /**
2089      * decoder bitstream buffer size
2090      * - encoding: Set by user.
2091      * - decoding: unused
2092      */
2093     int rc_buffer_size;
2094
2095     /**
2096      * ratecontrol override, see RcOverride
2097      * - encoding: Allocated/set/freed by user.
2098      * - decoding: unused
2099      */
2100     int rc_override_count;
2101     RcOverride *rc_override;
2102
2103     /**
2104      * rate control equation
2105      * - encoding: Set by user
2106      * - decoding: unused
2107      */
2108     const char *rc_eq;
2109
2110     /**
2111      * maximum bitrate
2112      * - encoding: Set by user.
2113      * - decoding: unused
2114      */
2115     int rc_max_rate;
2116
2117     /**
2118      * minimum bitrate
2119      * - encoding: Set by user.
2120      * - decoding: unused
2121      */
2122     int rc_min_rate;
2123
2124     float rc_buffer_aggressivity;
2125
2126     /**
2127      * initial complexity for pass1 ratecontrol
2128      * - encoding: Set by user.
2129      * - decoding: unused
2130      */
2131     float rc_initial_cplx;
2132
2133     /**
2134      * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2135      * - encoding: Set by user.
2136      * - decoding: unused.
2137      */
2138     float rc_max_available_vbv_use;
2139
2140     /**
2141      * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2142      * - encoding: Set by user.
2143      * - decoding: unused.
2144      */
2145     float rc_min_vbv_overflow_use;
2146
2147     /**
2148      * Number of bits which should be loaded into the rc buffer before decoding starts.
2149      * - encoding: Set by user.
2150      * - decoding: unused
2151      */
2152     int rc_initial_buffer_occupancy;
2153
2154 #define FF_CODER_TYPE_VLC       0
2155 #define FF_CODER_TYPE_AC        1
2156 #define FF_CODER_TYPE_RAW       2
2157 #define FF_CODER_TYPE_RLE       3
2158 #define FF_CODER_TYPE_DEFLATE   4
2159     /**
2160      * coder type
2161      * - encoding: Set by user.
2162      * - decoding: unused
2163      */
2164     int coder_type;
2165
2166     /**
2167      * context model
2168      * - encoding: Set by user.
2169      * - decoding: unused
2170      */
2171     int context_model;
2172
2173     /**
2174      * minimum Lagrange multipler
2175      * - encoding: Set by user.
2176      * - decoding: unused
2177      */
2178     int lmin;
2179
2180     /**
2181      * maximum Lagrange multipler
2182      * - encoding: Set by user.
2183      * - decoding: unused
2184      */
2185     int lmax;
2186
2187     /**
2188      * frame skip threshold
2189      * - encoding: Set by user.
2190      * - decoding: unused
2191      */
2192     int frame_skip_threshold;
2193
2194     /**
2195      * frame skip factor
2196      * - encoding: Set by user.
2197      * - decoding: unused
2198      */
2199     int frame_skip_factor;
2200
2201     /**
2202      * frame skip exponent
2203      * - encoding: Set by user.
2204      * - decoding: unused
2205      */
2206     int frame_skip_exp;
2207
2208     /**
2209      * frame skip comparison function
2210      * - encoding: Set by user.
2211      * - decoding: unused
2212      */
2213     int frame_skip_cmp;
2214
2215     /**
2216      * trellis RD quantization
2217      * - encoding: Set by user.
2218      * - decoding: unused
2219      */
2220     int trellis;
2221
2222     /**
2223      * - encoding: Set by user.
2224      * - decoding: unused
2225      */
2226     int min_prediction_order;
2227
2228     /**
2229      * - encoding: Set by user.
2230      * - decoding: unused
2231      */
2232     int max_prediction_order;
2233
2234     /**
2235      * GOP timecode frame start number, in non drop frame format
2236      * - encoding: Set by user.
2237      * - decoding: unused
2238      */
2239     int64_t timecode_frame_start;
2240
2241     /* The RTP callback: This function is called    */
2242     /* every time the encoder has a packet to send. */
2243     /* It depends on the encoder if the data starts */
2244     /* with a Start Code (it should). H.263 does.   */
2245     /* mb_nb contains the number of macroblocks     */
2246     /* encoded in the RTP payload.                  */
2247     void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2248
2249     int rtp_payload_size;   /* The size of the RTP payload: the coder will  */
2250                             /* do its best to deliver a chunk with size     */
2251                             /* below rtp_payload_size, the chunk will start */
2252                             /* with a start code on some codecs like H.263. */
2253                             /* This doesn't take account of any particular  */
2254                             /* headers inside the transmitted RTP payload.  */
2255
2256     /* statistics, used for 2-pass encoding */
2257     int mv_bits;
2258     int header_bits;
2259     int i_tex_bits;
2260     int p_tex_bits;
2261     int i_count;
2262     int p_count;
2263     int skip_count;
2264     int misc_bits;
2265
2266     /**
2267      * number of bits used for the previously encoded frame
2268      * - encoding: Set by libavcodec.
2269      * - decoding: unused
2270      */
2271     int frame_bits;
2272
2273     /**
2274      * pass1 encoding statistics output buffer
2275      * - encoding: Set by libavcodec.
2276      * - decoding: unused
2277      */
2278     char *stats_out;
2279
2280     /**
2281      * pass2 encoding statistics input buffer
2282      * Concatenated stuff from stats_out of pass1 should be placed here.
2283      * - encoding: Allocated/set/freed by user.
2284      * - decoding: unused
2285      */
2286     char *stats_in;
2287
2288     /**
2289      * Work around bugs in encoders which sometimes cannot be detected automatically.
2290      * - encoding: Set by user
2291      * - decoding: Set by user
2292      */
2293     int workaround_bugs;
2294 #define FF_BUG_AUTODETECT       1  ///< autodetection
2295 #if FF_API_OLD_MSMPEG4
2296 #define FF_BUG_OLD_MSMPEG4      2
2297 #endif
2298 #define FF_BUG_XVID_ILACE       4
2299 #define FF_BUG_UMP4             8
2300 #define FF_BUG_NO_PADDING       16
2301 #define FF_BUG_AMV              32
2302 #if FF_API_AC_VLC
2303 #define FF_BUG_AC_VLC           0  ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2304 #endif
2305 #define FF_BUG_QPEL_CHROMA      64
2306 #define FF_BUG_STD_QPEL         128
2307 #define FF_BUG_QPEL_CHROMA2     256
2308 #define FF_BUG_DIRECT_BLOCKSIZE 512
2309 #define FF_BUG_EDGE             1024
2310 #define FF_BUG_HPEL_CHROMA      2048
2311 #define FF_BUG_DC_CLIP          4096
2312 #define FF_BUG_MS               8192 ///< Work around various bugs in Microsoft's broken decoders.
2313 #define FF_BUG_TRUNCATED       16384
2314
2315     /**
2316      * strictly follow the standard (MPEG4, ...).
2317      * - encoding: Set by user.
2318      * - decoding: Set by user.
2319      * Setting this to STRICT or higher means the encoder and decoder will
2320      * generally do stupid things, whereas setting it to unofficial or lower
2321      * will mean the encoder might produce output that is not supported by all
2322      * spec-compliant decoders. Decoders don't differentiate between normal,
2323      * unofficial and experimental (that is, they always try to decode things
2324      * when they can) unless they are explicitly asked to behave stupidly
2325      * (=strictly conform to the specs)
2326      */
2327     int strict_std_compliance;
2328 #define FF_COMPLIANCE_VERY_STRICT   2 ///< Strictly conform to an older more strict version of the spec or reference software.
2329 #define FF_COMPLIANCE_STRICT        1 ///< Strictly conform to all the things in the spec no matter what consequences.
2330 #define FF_COMPLIANCE_NORMAL        0
2331 #define FF_COMPLIANCE_UNOFFICIAL   -1 ///< Allow unofficial extensions
2332 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2333
2334     /**
2335      * error concealment flags
2336      * - encoding: unused
2337      * - decoding: Set by user.
2338      */
2339     int error_concealment;
2340 #define FF_EC_GUESS_MVS   1
2341 #define FF_EC_DEBLOCK     2
2342
2343     /**
2344      * debug
2345      * - encoding: Set by user.
2346      * - decoding: Set by user.
2347      */
2348     int debug;
2349 #define FF_DEBUG_PICT_INFO   1
2350 #define FF_DEBUG_RC          2
2351 #define FF_DEBUG_BITSTREAM   4
2352 #define FF_DEBUG_MB_TYPE     8
2353 #define FF_DEBUG_QP          16
2354 #if FF_API_DEBUG_MV
2355 /**
2356  * @deprecated this option does nothing
2357  */
2358 #define FF_DEBUG_MV          32
2359 #endif
2360 #define FF_DEBUG_DCT_COEFF   0x00000040
2361 #define FF_DEBUG_SKIP        0x00000080
2362 #define FF_DEBUG_STARTCODE   0x00000100
2363 #define FF_DEBUG_PTS         0x00000200
2364 #define FF_DEBUG_ER          0x00000400
2365 #define FF_DEBUG_MMCO        0x00000800
2366 #define FF_DEBUG_BUGS        0x00001000
2367 #if FF_API_DEBUG_MV
2368 #define FF_DEBUG_VIS_QP      0x00002000
2369 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2370 #endif
2371 #define FF_DEBUG_BUFFERS     0x00008000
2372 #define FF_DEBUG_THREADS     0x00010000
2373
2374 #if FF_API_DEBUG_MV
2375     /**
2376      * @deprecated this option does not have any effect
2377      */
2378     attribute_deprecated
2379     int debug_mv;
2380 #define FF_DEBUG_VIS_MV_P_FOR  0x00000001 //visualize forward predicted MVs of P frames
2381 #define FF_DEBUG_VIS_MV_B_FOR  0x00000002 //visualize forward predicted MVs of B frames
2382 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2383 #endif
2384
2385     /**
2386      * Error recognition; may misdetect some more or less valid parts as errors.
2387      * - encoding: unused
2388      * - decoding: Set by user.
2389      */
2390     int err_recognition;
2391
2392 /**
2393  * Verify checksums embedded in the bitstream (could be of either encoded or
2394  * decoded data, depending on the codec) and print an error message on mismatch.
2395  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2396  * decoder returning an error.
2397  */
2398 #define AV_EF_CRCCHECK  (1<<0)
2399 #define AV_EF_BITSTREAM (1<<1)
2400 #define AV_EF_BUFFER    (1<<2)
2401 #define AV_EF_EXPLODE   (1<<3)
2402
2403     /**
2404      * opaque 64bit number (generally a PTS) that will be reordered and
2405      * output in AVFrame.reordered_opaque
2406      * @deprecated in favor of pkt_pts
2407      * - encoding: unused
2408      * - decoding: Set by user.
2409      */
2410     int64_t reordered_opaque;
2411
2412     /**
2413      * Hardware accelerator in use
2414      * - encoding: unused.
2415      * - decoding: Set by libavcodec
2416      */
2417     struct AVHWAccel *hwaccel;
2418
2419     /**
2420      * Hardware accelerator context.
2421      * For some hardware accelerators, a global context needs to be
2422      * provided by the user. In that case, this holds display-dependent
2423      * data Libav cannot instantiate itself. Please refer to the
2424      * Libav HW accelerator documentation to know how to fill this
2425      * is. e.g. for VA API, this is a struct vaapi_context.
2426      * - encoding: unused
2427      * - decoding: Set by user
2428      */
2429     void *hwaccel_context;
2430
2431     /**
2432      * error
2433      * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2434      * - decoding: unused
2435      */
2436     uint64_t error[AV_NUM_DATA_POINTERS];
2437
2438     /**
2439      * DCT algorithm, see FF_DCT_* below
2440      * - encoding: Set by user.
2441      * - decoding: unused
2442      */
2443     int dct_algo;
2444 #define FF_DCT_AUTO    0
2445 #define FF_DCT_FASTINT 1
2446 #define FF_DCT_INT     2
2447 #define FF_DCT_MMX     3
2448 #define FF_DCT_ALTIVEC 5
2449 #define FF_DCT_FAAN    6
2450
2451     /**
2452      * IDCT algorithm, see FF_IDCT_* below.
2453      * - encoding: Set by user.
2454      * - decoding: Set by user.
2455      */
2456     int idct_algo;
2457 #define FF_IDCT_AUTO          0
2458 #define FF_IDCT_INT           1
2459 #define FF_IDCT_SIMPLE        2
2460 #define FF_IDCT_SIMPLEMMX     3
2461 #define FF_IDCT_ARM           7
2462 #define FF_IDCT_ALTIVEC       8
2463 #define FF_IDCT_SH4           9
2464 #define FF_IDCT_SIMPLEARM     10
2465 #define FF_IDCT_IPP           13
2466 #define FF_IDCT_XVIDMMX       14
2467 #define FF_IDCT_SIMPLEARMV5TE 16
2468 #define FF_IDCT_SIMPLEARMV6   17
2469 #define FF_IDCT_SIMPLEVIS     18
2470 #define FF_IDCT_FAAN          20
2471 #define FF_IDCT_SIMPLENEON    22
2472 #if FF_API_ARCH_ALPHA
2473 #define FF_IDCT_SIMPLEALPHA   23
2474 #endif
2475
2476     /**
2477      * bits per sample/pixel from the demuxer (needed for huffyuv).
2478      * - encoding: Set by libavcodec.
2479      * - decoding: Set by user.
2480      */
2481      int bits_per_coded_sample;
2482
2483     /**
2484      * Bits per sample/pixel of internal libavcodec pixel/sample format.
2485      * - encoding: set by user.
2486      * - decoding: set by libavcodec.
2487      */
2488     int bits_per_raw_sample;
2489
2490 #if FF_API_LOWRES
2491     /**
2492      * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2493      * - encoding: unused
2494      * - decoding: Set by user.
2495      *
2496      * @deprecated use decoder private options instead
2497      */
2498     attribute_deprecated int lowres;
2499 #endif
2500
2501     /**
2502      * the picture in the bitstream
2503      * - encoding: Set by libavcodec.
2504      * - decoding: unused
2505      */
2506     AVFrame *coded_frame;
2507
2508     /**
2509      * thread count
2510      * is used to decide how many independent tasks should be passed to execute()
2511      * - encoding: Set by user.
2512      * - decoding: Set by user.
2513      */
2514     int thread_count;
2515
2516     /**
2517      * Which multithreading methods to use.
2518      * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2519      * so clients which cannot provide future frames should not use it.
2520      *
2521      * - encoding: Set by user, otherwise the default is used.
2522      * - decoding: Set by user, otherwise the default is used.
2523      */
2524     int thread_type;
2525 #define FF_THREAD_FRAME   1 ///< Decode more than one frame at once
2526 #define FF_THREAD_SLICE   2 ///< Decode more than one part of a single frame at once
2527
2528     /**
2529      * Which multithreading methods are in use by the codec.
2530      * - encoding: Set by libavcodec.
2531      * - decoding: Set by libavcodec.
2532      */
2533     int active_thread_type;
2534
2535     /**
2536      * Set by the client if its custom get_buffer() callback can be called
2537      * synchronously from another thread, which allows faster multithreaded decoding.
2538      * draw_horiz_band() will be called from other threads regardless of this setting.
2539      * Ignored if the default get_buffer() is used.
2540      * - encoding: Set by user.
2541      * - decoding: Set by user.
2542      */
2543     int thread_safe_callbacks;
2544
2545     /**
2546      * The codec may call this to execute several independent things.
2547      * It will return only after finishing all tasks.
2548      * The user may replace this with some multithreaded implementation,
2549      * the default implementation will execute the parts serially.
2550      * @param count the number of things to execute
2551      * - encoding: Set by libavcodec, user can override.
2552      * - decoding: Set by libavcodec, user can override.
2553      */
2554     int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2555
2556     /**
2557      * The codec may call this to execute several independent things.
2558      * It will return only after finishing all tasks.
2559      * The user may replace this with some multithreaded implementation,
2560      * the default implementation will execute the parts serially.
2561      * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2562      * @param c context passed also to func
2563      * @param count the number of things to execute
2564      * @param arg2 argument passed unchanged to func
2565      * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2566      * @param func function that will be called count times, with jobnr from 0 to count-1.
2567      *             threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2568      *             two instances of func executing at the same time will have the same threadnr.
2569      * @return always 0 currently, but code should handle a future improvement where when any call to func
2570      *         returns < 0 no further calls to func may be done and < 0 is returned.
2571      * - encoding: Set by libavcodec, user can override.
2572      * - decoding: Set by libavcodec, user can override.
2573      */
2574     int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2575
2576 #if FF_API_THREAD_OPAQUE
2577     /**
2578      * @deprecated this field should not be used from outside of lavc
2579      */
2580     attribute_deprecated
2581     void *thread_opaque;
2582 #endif
2583
2584     /**
2585      * noise vs. sse weight for the nsse comparsion function
2586      * - encoding: Set by user.
2587      * - decoding: unused
2588      */
2589      int nsse_weight;
2590
2591     /**
2592      * profile
2593      * - encoding: Set by user.
2594      * - decoding: Set by libavcodec.
2595      */
2596      int profile;
2597 #define FF_PROFILE_UNKNOWN -99
2598 #define FF_PROFILE_RESERVED -100
2599
2600 #define FF_PROFILE_AAC_MAIN 0
2601 #define FF_PROFILE_AAC_LOW  1
2602 #define FF_PROFILE_AAC_SSR  2
2603 #define FF_PROFILE_AAC_LTP  3
2604 #define FF_PROFILE_AAC_HE   4
2605 #define FF_PROFILE_AAC_HE_V2 28
2606 #define FF_PROFILE_AAC_LD   22
2607 #define FF_PROFILE_AAC_ELD  38
2608 #define FF_PROFILE_MPEG2_AAC_LOW 128
2609 #define FF_PROFILE_MPEG2_AAC_HE  131
2610
2611 #define FF_PROFILE_DTS         20
2612 #define FF_PROFILE_DTS_ES      30
2613 #define FF_PROFILE_DTS_96_24   40
2614 #define FF_PROFILE_DTS_HD_HRA  50
2615 #define FF_PROFILE_DTS_HD_MA   60
2616
2617 #define FF_PROFILE_MPEG2_422    0
2618 #define FF_PROFILE_MPEG2_HIGH   1
2619 #define FF_PROFILE_MPEG2_SS     2
2620 #define FF_PROFILE_MPEG2_SNR_SCALABLE  3
2621 #define FF_PROFILE_MPEG2_MAIN   4
2622 #define FF_PROFILE_MPEG2_SIMPLE 5
2623
2624 #define FF_PROFILE_H264_CONSTRAINED  (1<<9)  // 8+1; constraint_set1_flag
2625 #define FF_PROFILE_H264_INTRA        (1<<11) // 8+3; constraint_set3_flag
2626
2627 #define FF_PROFILE_H264_BASELINE             66
2628 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2629 #define FF_PROFILE_H264_MAIN                 77
2630 #define FF_PROFILE_H264_EXTENDED             88
2631 #define FF_PROFILE_H264_HIGH                 100
2632 #define FF_PROFILE_H264_HIGH_10              110
2633 #define FF_PROFILE_H264_HIGH_10_INTRA        (110|FF_PROFILE_H264_INTRA)
2634 #define FF_PROFILE_H264_HIGH_422             122
2635 #define FF_PROFILE_H264_HIGH_422_INTRA       (122|FF_PROFILE_H264_INTRA)
2636 #define FF_PROFILE_H264_HIGH_444             144
2637 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE  244
2638 #define FF_PROFILE_H264_HIGH_444_INTRA       (244|FF_PROFILE_H264_INTRA)
2639 #define FF_PROFILE_H264_CAVLC_444            44
2640
2641 #define FF_PROFILE_VC1_SIMPLE   0
2642 #define FF_PROFILE_VC1_MAIN     1
2643 #define FF_PROFILE_VC1_COMPLEX  2
2644 #define FF_PROFILE_VC1_ADVANCED 3
2645
2646 #define FF_PROFILE_MPEG4_SIMPLE                     0
2647 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE            1
2648 #define FF_PROFILE_MPEG4_CORE                       2
2649 #define FF_PROFILE_MPEG4_MAIN                       3
2650 #define FF_PROFILE_MPEG4_N_BIT                      4
2651 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE           5
2652 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION      6
2653 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE     7
2654 #define FF_PROFILE_MPEG4_HYBRID                     8
2655 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME         9
2656 #define FF_PROFILE_MPEG4_CORE_SCALABLE             10
2657 #define FF_PROFILE_MPEG4_ADVANCED_CODING           11
2658 #define FF_PROFILE_MPEG4_ADVANCED_CORE             12
2659 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2660 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO             14
2661 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE           15
2662
2663 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0   0
2664 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1   1
2665 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION  2
2666 #define FF_PROFILE_JPEG2000_DCINEMA_2K              3
2667 #define FF_PROFILE_JPEG2000_DCINEMA_4K              4
2668
2669
2670 #define FF_PROFILE_HEVC_MAIN                        1
2671 #define FF_PROFILE_HEVC_MAIN_10                     2
2672 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE          3
2673
2674     /**
2675      * level
2676      * - encoding: Set by user.
2677      * - decoding: Set by libavcodec.
2678      */
2679      int level;
2680 #define FF_LEVEL_UNKNOWN -99
2681
2682     /**
2683      *
2684      * - encoding: unused
2685      * - decoding: Set by user.
2686      */
2687     enum AVDiscard skip_loop_filter;
2688
2689     /**
2690      *
2691      * - encoding: unused
2692      * - decoding: Set by user.
2693      */
2694     enum AVDiscard skip_idct;
2695
2696     /**
2697      *
2698      * - encoding: unused
2699      * - decoding: Set by user.
2700      */
2701     enum AVDiscard skip_frame;
2702
2703     /**
2704      * Header containing style information for text subtitles.
2705      * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2706      * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2707      * the Format line following. It shouldn't include any Dialogue line.
2708      * - encoding: Set/allocated/freed by user (before avcodec_open2())
2709      * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2710      */
2711     uint8_t *subtitle_header;
2712     int subtitle_header_size;
2713
2714 #if FF_API_ERROR_RATE
2715     /**
2716      * @deprecated use the 'error_rate' private AVOption of the mpegvideo
2717      * encoders
2718      */
2719     attribute_deprecated
2720     int error_rate;
2721 #endif
2722
2723 #if FF_API_CODEC_PKT
2724     /**
2725      * @deprecated this field is not supposed to be accessed from outside lavc
2726      */
2727     attribute_deprecated
2728     AVPacket *pkt;
2729 #endif
2730
2731     /**
2732      * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2733      * Used for compliant TS muxing.
2734      * - encoding: Set by libavcodec.
2735      * - decoding: unused.
2736      */
2737     uint64_t vbv_delay;
2738 } AVCodecContext;
2739
2740 /**
2741  * AVProfile.
2742  */
2743 typedef struct AVProfile {
2744     int profile;
2745     const char *name; ///< short name for the profile
2746 } AVProfile;
2747
2748 typedef struct AVCodecDefault AVCodecDefault;
2749
2750 struct AVSubtitle;
2751
2752 /**
2753  * AVCodec.
2754  */
2755 typedef struct AVCodec {
2756     /**
2757      * Name of the codec implementation.
2758      * The name is globally unique among encoders and among decoders (but an
2759      * encoder and a decoder can share the same name).
2760      * This is the primary way to find a codec from the user perspective.
2761      */
2762     const char *name;
2763     /**
2764      * Descriptive name for the codec, meant to be more human readable than name.
2765      * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
2766      */
2767     const char *long_name;
2768     enum AVMediaType type;
2769     enum AVCodecID id;
2770     /**
2771      * Codec capabilities.
2772      * see CODEC_CAP_*
2773      */
2774     int capabilities;
2775     const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
2776     const enum AVPixelFormat *pix_fmts;     ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
2777     const int *supported_samplerates;       ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
2778     const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
2779     const uint64_t *channel_layouts;         ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
2780 #if FF_API_LOWRES
2781     attribute_deprecated uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
2782 #endif
2783     const AVClass *priv_class;              ///< AVClass for the private context
2784     const AVProfile *profiles;              ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
2785
2786     /*****************************************************************
2787      * No fields below this line are part of the public API. They
2788      * may not be used outside of libavcodec and can be changed and
2789      * removed at will.
2790      * New public fields should be added right above.
2791      *****************************************************************
2792      */
2793     int priv_data_size;
2794     struct AVCodec *next;
2795     /**
2796      * @name Frame-level threading support functions
2797      * @{
2798      */
2799     /**
2800      * If defined, called on thread contexts when they are created.
2801      * If the codec allocates writable tables in init(), re-allocate them here.
2802      * priv_data will be set to a copy of the original.
2803      */
2804     int (*init_thread_copy)(AVCodecContext *);
2805     /**
2806      * Copy necessary context variables from a previous thread context to the current one.
2807      * If not defined, the next thread will start automatically; otherwise, the codec
2808      * must call ff_thread_finish_setup().
2809      *
2810      * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
2811      */
2812     int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
2813     /** @} */
2814
2815     /**
2816      * Private codec-specific defaults.
2817      */
2818     const AVCodecDefault *defaults;
2819
2820     /**
2821      * Initialize codec static data, called from avcodec_register().
2822      */
2823     void (*init_static_data)(struct AVCodec *codec);
2824
2825     int (*init)(AVCodecContext *);
2826     int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
2827                       const struct AVSubtitle *sub);
2828     /**
2829      * Encode data to an AVPacket.
2830      *
2831      * @param      avctx          codec context
2832      * @param      avpkt          output AVPacket (may contain a user-provided buffer)
2833      * @param[in]  frame          AVFrame containing the raw data to be encoded
2834      * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
2835      *                            non-empty packet was returned in avpkt.
2836      * @return 0 on success, negative error code on failure
2837      */
2838     int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
2839                    int *got_packet_ptr);
2840     int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
2841     int (*close)(AVCodecContext *);
2842     /**
2843      * Flush buffers.
2844      * Will be called when seeking
2845      */
2846     void (*flush)(AVCodecContext *);
2847 } AVCodec;
2848
2849 /**
2850  * AVHWAccel.
2851  */
2852 typedef struct AVHWAccel {
2853     /**
2854      * Name of the hardware accelerated codec.
2855      * The name is globally unique among encoders and among decoders (but an
2856      * encoder and a decoder can share the same name).
2857      */
2858     const char *name;
2859
2860     /**
2861      * Type of codec implemented by the hardware accelerator.
2862      *
2863      * See AVMEDIA_TYPE_xxx
2864      */
2865     enum AVMediaType type;
2866
2867     /**
2868      * Codec implemented by the hardware accelerator.
2869      *
2870      * See AV_CODEC_ID_xxx
2871      */
2872     enum AVCodecID id;
2873
2874     /**
2875      * Supported pixel format.
2876      *
2877      * Only hardware accelerated formats are supported here.
2878      */
2879     enum AVPixelFormat pix_fmt;
2880
2881     /**
2882      * Hardware accelerated codec capabilities.
2883      * see FF_HWACCEL_CODEC_CAP_*
2884      */
2885     int capabilities;
2886
2887     struct AVHWAccel *next;
2888
2889     /**
2890      * Called at the beginning of each frame or field picture.
2891      *
2892      * Meaningful frame information (codec specific) is guaranteed to
2893      * be parsed at this point. This function is mandatory.
2894      *
2895      * Note that buf can be NULL along with buf_size set to 0.
2896      * Otherwise, this means the whole frame is available at this point.
2897      *
2898      * @param avctx the codec context
2899      * @param buf the frame data buffer base
2900      * @param buf_size the size of the frame in bytes
2901      * @return zero if successful, a negative value otherwise
2902      */
2903     int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2904
2905     /**
2906      * Callback for each slice.
2907      *
2908      * Meaningful slice information (codec specific) is guaranteed to
2909      * be parsed at this point. This function is mandatory.
2910      *
2911      * @param avctx the codec context
2912      * @param buf the slice data buffer base
2913      * @param buf_size the size of the slice in bytes
2914      * @return zero if successful, a negative value otherwise
2915      */
2916     int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2917
2918     /**
2919      * Called at the end of each frame or field picture.
2920      *
2921      * The whole picture is parsed at this point and can now be sent
2922      * to the hardware accelerator. This function is mandatory.
2923      *
2924      * @param avctx the codec context
2925      * @return zero if successful, a negative value otherwise
2926      */
2927     int (*end_frame)(AVCodecContext *avctx);
2928
2929     /**
2930      * Size of HW accelerator private data.
2931      *
2932      * Private data is allocated with av_mallocz() before
2933      * AVCodecContext.get_buffer() and deallocated after
2934      * AVCodecContext.release_buffer().
2935      */
2936     int priv_data_size;
2937 } AVHWAccel;
2938
2939 /**
2940  * @defgroup lavc_picture AVPicture
2941  *
2942  * Functions for working with AVPicture
2943  * @{
2944  */
2945
2946 /**
2947  * four components are given, that's all.
2948  * the last component is alpha
2949  */
2950 typedef struct AVPicture {
2951     uint8_t *data[AV_NUM_DATA_POINTERS];
2952     int linesize[AV_NUM_DATA_POINTERS];     ///< number of bytes per line
2953 } AVPicture;
2954
2955 /**
2956  * @}
2957  */
2958
2959 #define AVPALETTE_SIZE 1024
2960 #define AVPALETTE_COUNT 256
2961
2962 enum AVSubtitleType {
2963     SUBTITLE_NONE,
2964
2965     SUBTITLE_BITMAP,                ///< A bitmap, pict will be set
2966
2967     /**
2968      * Plain text, the text field must be set by the decoder and is
2969      * authoritative. ass and pict fields may contain approximations.
2970      */
2971     SUBTITLE_TEXT,
2972
2973     /**
2974      * Formatted text, the ass field must be set by the decoder and is
2975      * authoritative. pict and text fields may contain approximations.
2976      */
2977     SUBTITLE_ASS,
2978 };
2979
2980 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2981
2982 typedef struct AVSubtitleRect {
2983     int x;         ///< top left corner  of pict, undefined when pict is not set
2984     int y;         ///< top left corner  of pict, undefined when pict is not set
2985     int w;         ///< width            of pict, undefined when pict is not set
2986     int h;         ///< height           of pict, undefined when pict is not set
2987     int nb_colors; ///< number of colors in pict, undefined when pict is not set
2988
2989     /**
2990      * data+linesize for the bitmap of this subtitle.
2991      * can be set for text/ass as well once they where rendered
2992      */
2993     AVPicture pict;
2994     enum AVSubtitleType type;
2995
2996     char *text;                     ///< 0 terminated plain UTF-8 text
2997
2998     /**
2999      * 0 terminated ASS/SSA compatible event line.
3000      * The pressentation of this is unaffected by the other values in this
3001      * struct.
3002      */
3003     char *ass;
3004     int flags;
3005 } AVSubtitleRect;
3006
3007 typedef struct AVSubtitle {
3008     uint16_t format; /* 0 = graphics */
3009     uint32_t start_display_time; /* relative to packet pts, in ms */
3010     uint32_t end_display_time; /* relative to packet pts, in ms */
3011     unsigned num_rects;
3012     AVSubtitleRect **rects;
3013     int64_t pts;    ///< Same as packet pts, in AV_TIME_BASE
3014 } AVSubtitle;
3015
3016 /**
3017  * If c is NULL, returns the first registered codec,
3018  * if c is non-NULL, returns the next registered codec after c,
3019  * or NULL if c is the last one.
3020  */
3021 AVCodec *av_codec_next(const AVCodec *c);
3022
3023 /**
3024  * Return the LIBAVCODEC_VERSION_INT constant.
3025  */
3026 unsigned avcodec_version(void);
3027
3028 /**
3029  * Return the libavcodec build-time configuration.
3030  */
3031 const char *avcodec_configuration(void);
3032
3033 /**
3034  * Return the libavcodec license.
3035  */
3036 const char *avcodec_license(void);
3037
3038 /**
3039  * Register the codec codec and initialize libavcodec.
3040  *
3041  * @warning either this function or avcodec_register_all() must be called
3042  * before any other libavcodec functions.
3043  *
3044  * @see avcodec_register_all()
3045  */
3046 void avcodec_register(AVCodec *codec);
3047
3048 /**
3049  * Register all the codecs, parsers and bitstream filters which were enabled at
3050  * configuration time. If you do not call this function you can select exactly
3051  * which formats you want to support, by using the individual registration
3052  * functions.
3053  *
3054  * @see avcodec_register
3055  * @see av_register_codec_parser
3056  * @see av_register_bitstream_filter
3057  */
3058 void avcodec_register_all(void);
3059
3060 /**
3061  * Allocate an AVCodecContext and set its fields to default values.  The
3062  * resulting struct can be deallocated by calling avcodec_close() on it followed
3063  * by av_free().
3064  *
3065  * @param codec if non-NULL, allocate private data and initialize defaults
3066  *              for the given codec. It is illegal to then call avcodec_open2()
3067  *              with a different codec.
3068  *              If NULL, then the codec-specific defaults won't be initialized,
3069  *              which may result in suboptimal default settings (this is
3070  *              important mainly for encoders, e.g. libx264).
3071  *
3072  * @return An AVCodecContext filled with default values or NULL on failure.
3073  * @see avcodec_get_context_defaults
3074  */
3075 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3076
3077 /**
3078  * Set the fields of the given AVCodecContext to default values corresponding
3079  * to the given codec (defaults may be codec-dependent).
3080  *
3081  * Do not call this function if a non-NULL codec has been passed
3082  * to avcodec_alloc_context3() that allocated this AVCodecContext.
3083  * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3084  * different codec on this AVCodecContext.
3085  */
3086 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3087
3088 /**
3089  * Get the AVClass for AVCodecContext. It can be used in combination with
3090  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3091  *
3092  * @see av_opt_find().
3093  */
3094 const AVClass *avcodec_get_class(void);
3095
3096 /**
3097  * Copy the settings of the source AVCodecContext into the destination
3098  * AVCodecContext. The resulting destination codec context will be
3099  * unopened, i.e. you are required to call avcodec_open2() before you
3100  * can use this AVCodecContext to decode/encode video/audio data.
3101  *
3102  * @param dest target codec context, should be initialized with
3103  *             avcodec_alloc_context3(), but otherwise uninitialized
3104  * @param src source codec context
3105  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3106  */
3107 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3108
3109 #if FF_API_AVFRAME_LAVC
3110 /**
3111  * @deprecated use av_frame_alloc()
3112  */
3113 attribute_deprecated
3114 AVFrame *avcodec_alloc_frame(void);
3115
3116 /**
3117  * Set the fields of the given AVFrame to default values.
3118  *
3119  * @param frame The AVFrame of which the fields should be set to default values.
3120  *
3121  * @deprecated use av_frame_unref()
3122  */
3123 attribute_deprecated
3124 void avcodec_get_frame_defaults(AVFrame *frame);
3125
3126 /**
3127  * Free the frame and any dynamically allocated objects in it,
3128  * e.g. extended_data.
3129  *
3130  * @param frame frame to be freed. The pointer will be set to NULL.
3131  *
3132  * @warning this function does NOT free the data buffers themselves
3133  * (it does not know how, since they might have been allocated with
3134  *  a custom get_buffer()).
3135  *
3136  * @deprecated use av_frame_free()
3137  */
3138 attribute_deprecated
3139 void avcodec_free_frame(AVFrame **frame);
3140 #endif
3141
3142 /**
3143  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3144  * function the context has to be allocated with avcodec_alloc_context3().
3145  *
3146  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3147  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3148  * retrieving a codec.
3149  *
3150  * @warning This function is not thread safe!
3151  *
3152  * @code
3153  * avcodec_register_all();
3154  * av_dict_set(&opts, "b", "2.5M", 0);
3155  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3156  * if (!codec)
3157  *     exit(1);
3158  *
3159  * context = avcodec_alloc_context3(codec);
3160  *
3161  * if (avcodec_open2(context, codec, opts) < 0)
3162  *     exit(1);
3163  * @endcode
3164  *
3165  * @param avctx The context to initialize.
3166  * @param codec The codec to open this context for. If a non-NULL codec has been
3167  *              previously passed to avcodec_alloc_context3() or
3168  *              avcodec_get_context_defaults3() for this context, then this
3169  *              parameter MUST be either NULL or equal to the previously passed
3170  *              codec.
3171  * @param options A dictionary filled with AVCodecContext and codec-private options.
3172  *                On return this object will be filled with options that were not found.
3173  *
3174  * @return zero on success, a negative value on error
3175  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3176  *      av_dict_set(), av_opt_find().
3177  */
3178 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3179
3180 /**
3181  * Close a given AVCodecContext and free all the data associated with it
3182  * (but not the AVCodecContext itself).
3183  *
3184  * Calling this function on an AVCodecContext that hasn't been opened will free
3185  * the codec-specific data allocated in avcodec_alloc_context3() /
3186  * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3187  * do nothing.
3188  */
3189 int avcodec_close(AVCodecContext *avctx);
3190
3191 /**
3192  * Free all allocated data in the given subtitle struct.
3193  *
3194  * @param sub AVSubtitle to free.
3195  */
3196 void avsubtitle_free(AVSubtitle *sub);
3197
3198 /**
3199  * @}
3200  */
3201
3202 /**
3203  * @addtogroup lavc_packet
3204  * @{
3205  */
3206
3207 #if FF_API_DESTRUCT_PACKET
3208 /**
3209  * Default packet destructor.
3210  * @deprecated use the AVBuffer API instead
3211  */
3212 attribute_deprecated
3213 void av_destruct_packet(AVPacket *pkt);
3214 #endif
3215
3216 /**
3217  * Initialize optional fields of a packet with default values.
3218  *
3219  * Note, this does not touch the data and size members, which have to be
3220  * initialized separately.
3221  *
3222  * @param pkt packet
3223  */
3224 void av_init_packet(AVPacket *pkt);
3225
3226 /**
3227  * Allocate the payload of a packet and initialize its fields with
3228  * default values.
3229  *
3230  * @param pkt packet
3231  * @param size wanted payload size
3232  * @return 0 if OK, AVERROR_xxx otherwise
3233  */
3234 int av_new_packet(AVPacket *pkt, int size);
3235
3236 /**
3237  * Reduce packet size, correctly zeroing padding
3238  *
3239  * @param pkt packet
3240  * @param size new size
3241  */
3242 void av_shrink_packet(AVPacket *pkt, int size);
3243
3244 /**
3245  * Increase packet size, correctly zeroing padding
3246  *
3247  * @param pkt packet
3248  * @param grow_by number of bytes by which to increase the size of the packet
3249  */
3250 int av_grow_packet(AVPacket *pkt, int grow_by);
3251
3252 /**
3253  * Initialize a reference-counted packet from av_malloc()ed data.
3254  *
3255  * @param pkt packet to be initialized. This function will set the data, size,
3256  *        buf and destruct fields, all others are left untouched.
3257  * @param data Data allocated by av_malloc() to be used as packet data. If this
3258  *        function returns successfully, the data is owned by the underlying AVBuffer.
3259  *        The caller may not access the data through other means.
3260  * @param size size of data in bytes, without the padding. I.e. the full buffer
3261  *        size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
3262  *
3263  * @return 0 on success, a negative AVERROR on error
3264  */
3265 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
3266
3267 /**
3268  * @warning This is a hack - the packet memory allocation stuff is broken. The
3269  * packet is allocated if it was not really allocated.
3270  */
3271 int av_dup_packet(AVPacket *pkt);
3272
3273 /**
3274  * Free a packet.
3275  *
3276  * @param pkt packet to free
3277  */
3278 void av_free_packet(AVPacket *pkt);
3279
3280 /**
3281  * Allocate new information of a packet.
3282  *
3283  * @param pkt packet
3284  * @param type side information type
3285  * @param size side information size
3286  * @return pointer to fresh allocated data or NULL otherwise
3287  */
3288 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3289                                  int size);
3290
3291 /**
3292  * Shrink the already allocated side data buffer
3293  *
3294  * @param pkt packet
3295  * @param type side information type
3296  * @param size new side information size
3297  * @return 0 on success, < 0 on failure
3298  */
3299 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3300                                int size);
3301
3302 /**
3303  * Get side information from packet.
3304  *
3305  * @param pkt packet
3306  * @param type desired side information type
3307  * @param size pointer for side information size to store (optional)
3308  * @return pointer to data if present or NULL otherwise
3309  */
3310 uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3311                                  int *size);
3312
3313 /**
3314  * Convenience function to free all the side data stored.
3315  * All the other fields stay untouched.
3316  *
3317  * @param pkt packet
3318  */
3319 void av_packet_free_side_data(AVPacket *pkt);
3320
3321 /**
3322  * Setup a new reference to the data described by a given packet
3323  *
3324  * If src is reference-counted, setup dst as a new reference to the
3325  * buffer in src. Otherwise allocate a new buffer in dst and copy the
3326  * data from src into it.
3327  *
3328  * All the other fields are copied from src.
3329  *
3330  * @see av_packet_unref
3331  *
3332  * @param dst Destination packet
3333  * @param src Source packet
3334  *
3335  * @return 0 on success, a negative AVERROR on error.
3336  */
3337 int av_packet_ref(AVPacket *dst, AVPacket *src);
3338
3339 /**
3340  * Wipe the packet.
3341  *
3342  * Unreference the buffer referenced by the packet and reset the
3343  * remaining packet fields to their default values.
3344  *
3345  * @param pkt The packet to be unreferenced.
3346  */
3347 void av_packet_unref(AVPacket *pkt);
3348
3349 /**
3350  * Move every field in src to dst and reset src.
3351  *
3352  * @see av_packet_unref
3353  *
3354  * @param src Source packet, will be reset
3355  * @param dst Destination packet
3356  */
3357 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
3358
3359 /**
3360  * Copy only "properties" fields from src to dst.
3361  *
3362  * Properties for the purpose of this function are all the fields
3363  * beside those related to the packet data (buf, data, size)
3364  *
3365  * @param dst Destination packet
3366  * @param src Source packet
3367  *
3368  * @return 0 on success AVERROR on failure.
3369  *
3370  */
3371 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
3372
3373 /**
3374  * @}
3375  */
3376
3377 /**
3378  * @addtogroup lavc_decoding
3379  * @{
3380  */
3381
3382 /**
3383  * Find a registered decoder with a matching codec ID.
3384  *
3385  * @param id AVCodecID of the requested decoder
3386  * @return A decoder if one was found, NULL otherwise.
3387  */
3388 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3389
3390 /**
3391  * Find a registered decoder with the specified name.
3392  *
3393  * @param name name of the requested decoder
3394  * @return A decoder if one was found, NULL otherwise.
3395  */
3396 AVCodec *avcodec_find_decoder_by_name(const char *name);
3397
3398 #if FF_API_GET_BUFFER
3399 attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
3400 attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
3401 attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
3402 #endif
3403
3404 /**
3405  * The default callback for AVCodecContext.get_buffer2(). It is made public so
3406  * it can be called by custom get_buffer2() implementations for decoders without
3407  * CODEC_CAP_DR1 set.
3408  */
3409 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3410
3411 #if FF_API_EMU_EDGE
3412 /**
3413  * Return the amount of padding in pixels which the get_buffer callback must
3414  * provide around the edge of the image for codecs which do not have the
3415  * CODEC_FLAG_EMU_EDGE flag.
3416  *
3417  * @return Required padding in pixels.
3418  *
3419  * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
3420  * needed
3421  */
3422 attribute_deprecated
3423 unsigned avcodec_get_edge_width(void);
3424 #endif
3425
3426 /**
3427  * Modify width and height values so that they will result in a memory
3428  * buffer that is acceptable for the codec if you do not use any horizontal
3429  * padding.
3430  *
3431  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3432  */
3433 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3434
3435 /**
3436  * Modify width and height values so that they will result in a memory
3437  * buffer that is acceptable for the codec if you also ensure that all
3438  * line sizes are a multiple of the respective linesize_align[i].
3439  *
3440  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3441  */
3442 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3443                                int linesize_align[AV_NUM_DATA_POINTERS]);
3444
3445 /**
3446  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3447  *
3448  * Some decoders may support multiple frames in a single AVPacket. Such
3449  * decoders would then just decode the first frame and the return value would be
3450  * less than the packet size. In this case, avcodec_decode_audio4 has to be
3451  * called again with an AVPacket containing the remaining data in order to
3452  * decode the second frame, etc...  Even if no frames are returned, the packet
3453  * needs to be fed to the decoder with remaining data until it is completely
3454  * consumed or an error occurs.
3455  *
3456  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
3457  * and output. This means that for some packets they will not immediately
3458  * produce decoded output and need to be flushed at the end of decoding to get
3459  * all the decoded data. Flushing is done by calling this function with packets
3460  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3461  * returning samples. It is safe to flush even those decoders that are not
3462  * marked with CODEC_CAP_DELAY, then no samples will be returned.
3463  *
3464  * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
3465  *          larger than the actual read bytes because some optimized bitstream
3466  *          readers read 32 or 64 bits at once and could read over the end.
3467  *
3468  * @param      avctx the codec context
3469  * @param[out] frame The AVFrame in which to store decoded audio samples.
3470  *                   The decoder will allocate a buffer for the decoded frame by
3471  *                   calling the AVCodecContext.get_buffer2() callback.
3472  *                   When AVCodecContext.refcounted_frames is set to 1, the frame is
3473  *                   reference counted and the returned reference belongs to the
3474  *                   caller. The caller must release the frame using av_frame_unref()
3475  *                   when the frame is no longer needed. The caller may safely write
3476  *                   to the frame if av_frame_is_writable() returns 1.
3477  *                   When AVCodecContext.refcounted_frames is set to 0, the returned
3478  *                   reference belongs to the decoder and is valid only until the
3479  *                   next call to this function or until closing or flushing the
3480  *                   decoder. The caller may not write to it.
3481  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3482  *                           non-zero. Note that this field being set to zero
3483  *                           does not mean that an error has occurred. For
3484  *                           decoders with CODEC_CAP_DELAY set, no given decode
3485  *                           call is guaranteed to produce a frame.
3486  * @param[in]  avpkt The input AVPacket containing the input buffer.
3487  *                   At least avpkt->data and avpkt->size should be set. Some
3488  *                   decoders might also require additional fields to be set.
3489  * @return A negative error code is returned if an error occurred during
3490  *         decoding, otherwise the number of bytes consumed from the input
3491  *         AVPacket is returned.
3492  */
3493 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3494                           int *got_frame_ptr, AVPacket *avpkt);
3495
3496 /**
3497  * Decode the video frame of size avpkt->size from avpkt->data into picture.
3498  * Some decoders may support multiple frames in a single AVPacket, such
3499  * decoders would then just decode the first frame.
3500  *
3501  * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3502  * the actual read bytes because some optimized bitstream readers read 32 or 64
3503  * bits at once and could read over the end.
3504  *
3505  * @warning The end of the input buffer buf should be set to 0 to ensure that
3506  * no overreading happens for damaged MPEG streams.
3507  *
3508  * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3509  * between input and output, these need to be fed with avpkt->data=NULL,
3510  * avpkt->size=0 at the end to return the remaining frames.
3511  *
3512  * @param avctx the codec context
3513  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3514  *             Use av_frame_alloc() to get an AVFrame. The codec will
3515  *             allocate memory for the actual bitmap by calling the
3516  *             AVCodecContext.get_buffer2() callback.
3517  *             When AVCodecContext.refcounted_frames is set to 1, the frame is
3518  *             reference counted and the returned reference belongs to the
3519  *             caller. The caller must release the frame using av_frame_unref()
3520  *             when the frame is no longer needed. The caller may safely write
3521  *             to the frame if av_frame_is_writable() returns 1.
3522  *             When AVCodecContext.refcounted_frames is set to 0, the returned
3523  *             reference belongs to the decoder and is valid only until the
3524  *             next call to this function or until closing or flushing the
3525  *             decoder. The caller may not write to it.
3526  *
3527  * @param[in] avpkt The input AVpacket containing the input buffer.
3528  *            You can create such packet with av_init_packet() and by then setting
3529  *            data and size, some decoders might in addition need other fields like
3530  *            flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3531  *            fields possible.
3532  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3533  * @return On error a negative value is returned, otherwise the number of bytes
3534  * used or zero if no frame could be decompressed.
3535  */
3536 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3537                          int *got_picture_ptr,
3538                          AVPacket *avpkt);
3539
3540 /**
3541  * Decode a subtitle message.
3542  * Return a negative value on error, otherwise return the number of bytes used.
3543  * If no subtitle could be decompressed, got_sub_ptr is zero.
3544  * Otherwise, the subtitle is stored in *sub.
3545  * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3546  * simplicity, because the performance difference is expect to be negligible
3547  * and reusing a get_buffer written for video codecs would probably perform badly
3548  * due to a potentially very different allocation pattern.
3549  *
3550  * @param avctx the codec context
3551  * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
3552                    freed with avsubtitle_free if *got_sub_ptr is set.
3553  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3554  * @param[in] avpkt The input AVPacket containing the input buffer.
3555  */
3556 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3557                             int *got_sub_ptr,
3558                             AVPacket *avpkt);
3559
3560 /**
3561  * @defgroup lavc_parsing Frame parsing
3562  * @{
3563  */
3564
3565 enum AVPictureStructure {
3566     AV_PICTURE_STRUCTURE_UNKNOWN,      //< unknown
3567     AV_PICTURE_STRUCTURE_TOP_FIELD,    //< coded as top field
3568     AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3569     AV_PICTURE_STRUCTURE_FRAME,        //< coded as frame
3570 };
3571
3572 typedef struct AVCodecParserContext {
3573     void *priv_data;
3574     struct AVCodecParser *parser;
3575     int64_t frame_offset; /* offset of the current frame */
3576     int64_t cur_offset; /* current offset
3577                            (incremented by each av_parser_parse()) */
3578     int64_t next_frame_offset; /* offset of the next frame */
3579     /* video info */
3580     int pict_type; /* XXX: Put it back in AVCodecContext. */
3581     /**
3582      * This field is used for proper frame duration computation in lavf.
3583      * It signals, how much longer the frame duration of the current frame
3584      * is compared to normal frame duration.
3585      *
3586      * frame_duration = (1 + repeat_pict) * time_base
3587      *
3588      * It is used by codecs like H.264 to display telecined material.
3589      */
3590     int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3591     int64_t pts;     /* pts of the current frame */
3592     int64_t dts;     /* dts of the current frame */
3593
3594     /* private data */
3595     int64_t last_pts;
3596     int64_t last_dts;
3597     int fetch_timestamp;
3598
3599 #define AV_PARSER_PTS_NB 4
3600     int cur_frame_start_index;
3601     int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3602     int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3603     int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3604
3605     int flags;
3606 #define PARSER_FLAG_COMPLETE_FRAMES           0x0001
3607 #define PARSER_FLAG_ONCE                      0x0002
3608 /// Set if the parser has a valid file offset
3609 #define PARSER_FLAG_FETCHED_OFFSET            0x0004
3610
3611     int64_t offset;      ///< byte offset from starting packet start
3612     int64_t cur_frame_end[AV_PARSER_PTS_NB];
3613
3614     /**
3615      * Set by parser to 1 for key frames and 0 for non-key frames.
3616      * It is initialized to -1, so if the parser doesn't set this flag,
3617      * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3618      * will be used.
3619      */
3620     int key_frame;
3621
3622     /**
3623      * Time difference in stream time base units from the pts of this
3624      * packet to the point at which the output from the decoder has converged
3625      * independent from the availability of previous frames. That is, the
3626      * frames are virtually identical no matter if decoding started from
3627      * the very first frame or from this keyframe.
3628      * Is AV_NOPTS_VALUE if unknown.
3629      * This field is not the display duration of the current frame.
3630      * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
3631      * set.
3632      *
3633      * The purpose of this field is to allow seeking in streams that have no
3634      * keyframes in the conventional sense. It corresponds to the
3635      * recovery point SEI in H.264 and match_time_delta in NUT. It is also
3636      * essential for some types of subtitle streams to ensure that all
3637      * subtitles are correctly displayed after seeking.
3638      */
3639     int64_t convergence_duration;
3640
3641     // Timestamp generation support:
3642     /**
3643      * Synchronization point for start of timestamp generation.
3644      *
3645      * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3646      * (default).
3647      *
3648      * For example, this corresponds to presence of H.264 buffering period
3649      * SEI message.
3650      */
3651     int dts_sync_point;
3652
3653     /**
3654      * Offset of the current timestamp against last timestamp sync point in
3655      * units of AVCodecContext.time_base.
3656      *
3657      * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3658      * contain a valid timestamp offset.
3659      *
3660      * Note that the timestamp of sync point has usually a nonzero
3661      * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3662      * the next frame after timestamp sync point will be usually 1.
3663      *
3664      * For example, this corresponds to H.264 cpb_removal_delay.
3665      */
3666     int dts_ref_dts_delta;
3667
3668     /**
3669      * Presentation delay of current frame in units of AVCodecContext.time_base.
3670      *
3671      * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3672      * contain valid non-negative timestamp delta (presentation time of a frame
3673      * must not lie in the past).
3674      *
3675      * This delay represents the difference between decoding and presentation
3676      * time of the frame.
3677      *
3678      * For example, this corresponds to H.264 dpb_output_delay.
3679      */
3680     int pts_dts_delta;
3681
3682     /**
3683      * Position of the packet in file.
3684      *
3685      * Analogous to cur_frame_pts/dts
3686      */
3687     int64_t cur_frame_pos[AV_PARSER_PTS_NB];
3688
3689     /**
3690      * Byte position of currently parsed frame in stream.
3691      */
3692     int64_t pos;
3693
3694     /**
3695      * Previous frame byte position.
3696      */
3697     int64_t last_pos;
3698
3699     /**
3700      * Duration of the current frame.
3701      * For audio, this is in units of 1 / AVCodecContext.sample_rate.
3702      * For all other types, this is in units of AVCodecContext.time_base.
3703      */
3704     int duration;
3705
3706     enum AVFieldOrder field_order;
3707
3708     /**
3709      * Indicate whether a picture is coded as a frame, top field or bottom field.
3710      *
3711      * For example, H.264 field_pic_flag equal to 0 corresponds to
3712      * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
3713      * equal to 1 and bottom_field_flag equal to 0 corresponds to
3714      * AV_PICTURE_STRUCTURE_TOP_FIELD.
3715      */
3716     enum AVPictureStructure picture_structure;
3717
3718     /**
3719      * Picture number incremented in presentation or output order.
3720      * This field may be reinitialized at the first picture of a new sequence.
3721      *
3722      * For example, this corresponds to H.264 PicOrderCnt.
3723      */
3724     int output_picture_number;
3725 } AVCodecParserContext;
3726
3727 typedef struct AVCodecParser {
3728     int codec_ids[5]; /* several codec IDs are permitted */
3729     int priv_data_size;
3730     int (*parser_init)(AVCodecParserContext *s);
3731     int (*parser_parse)(AVCodecParserContext *s,
3732                         AVCodecContext *avctx,
3733                         const uint8_t **poutbuf, int *poutbuf_size,
3734                         const uint8_t *buf, int buf_size);
3735     void (*parser_close)(AVCodecParserContext *s);
3736     int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3737     struct AVCodecParser *next;
3738 } AVCodecParser;
3739
3740 AVCodecParser *av_parser_next(AVCodecParser *c);
3741
3742 void av_register_codec_parser(AVCodecParser *parser);
3743 AVCodecParserContext *av_parser_init(int codec_id);
3744
3745 /**
3746  * Parse a packet.
3747  *
3748  * @param s             parser context.
3749  * @param avctx         codec context.
3750  * @param poutbuf       set to pointer to parsed buffer or NULL if not yet finished.
3751  * @param poutbuf_size  set to size of parsed buffer or zero if not yet finished.
3752  * @param buf           input buffer.
3753  * @param buf_size      input length, to signal EOF, this should be 0 (so that the last frame can be output).
3754  * @param pts           input presentation timestamp.
3755  * @param dts           input decoding timestamp.
3756  * @param pos           input byte position in stream.
3757  * @return the number of bytes of the input bitstream used.
3758  *
3759  * Example:
3760  * @code
3761  *   while(in_len){
3762  *       len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3763  *                                        in_data, in_len,
3764  *                                        pts, dts, pos);
3765  *       in_data += len;
3766  *       in_len  -= len;
3767  *
3768  *       if(size)
3769  *          decode_frame(data, size);
3770  *   }
3771  * @endcode
3772  */
3773 int av_parser_parse2(AVCodecParserContext *s,
3774                      AVCodecContext *avctx,
3775                      uint8_t **poutbuf, int *poutbuf_size,
3776                      const uint8_t *buf, int buf_size,
3777                      int64_t pts, int64_t dts,
3778                      int64_t pos);
3779
3780 /**
3781  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
3782  * @deprecated use AVBitstreamFilter
3783  */
3784 int av_parser_change(AVCodecParserContext *s,
3785                      AVCodecContext *avctx,
3786                      uint8_t **poutbuf, int *poutbuf_size,
3787                      const uint8_t *buf, int buf_size, int keyframe);
3788 void av_parser_close(AVCodecParserContext *s);
3789
3790 /**
3791  * @}
3792  * @}
3793  */
3794
3795 /**
3796  * @addtogroup lavc_encoding
3797  * @{
3798  */
3799
3800 /**
3801  * Find a registered encoder with a matching codec ID.
3802  *
3803  * @param id AVCodecID of the requested encoder
3804  * @return An encoder if one was found, NULL otherwise.
3805  */
3806 AVCodec *avcodec_find_encoder(enum AVCodecID id);
3807
3808 /**
3809  * Find a registered encoder with the specified name.
3810  *
3811  * @param name name of the requested encoder
3812  * @return An encoder if one was found, NULL otherwise.
3813  */
3814 AVCodec *avcodec_find_encoder_by_name(const char *name);
3815
3816 /**
3817  * Encode a frame of audio.
3818  *
3819  * Takes input samples from frame and writes the next output packet, if
3820  * available, to avpkt. The output packet does not necessarily contain data for
3821  * the most recent frame, as encoders can delay, split, and combine input frames
3822  * internally as needed.
3823  *
3824  * @param avctx     codec context
3825  * @param avpkt     output AVPacket.
3826  *                  The user can supply an output buffer by setting
3827  *                  avpkt->data and avpkt->size prior to calling the
3828