FFmpeg源代码简单分析-通用-结构体分析-AVCodec
参考链接
- FFMPEG结构体分析：AVCodec_雷霄骅的博客-CSDN博客_avcodec
AVCodec
- AVCodec是存储编解码器信息的结构体
- 结构体的定义位于avcodec.h文件中
- 最主要的几个变量
- const char *name：编解码器的名字，比较短
- const char *long_name：编解码器的名字，全称，比较长
- enum AVMediaType type：指明了类型，是视频，音频，还是字幕
- enum AVCodecID id：ID，不重复
- const AVRational *supported_framerates：支持的帧率（仅视频）
- const enum AVPixelFormat *pix_fmts：支持的像素格式（仅视频）
- const int *supported_samplerates：支持的采样率（仅音频）
- const enum AVSampleFormat *sample_fmts：支持的采样格式（仅音频）
- const uint64_t *channel_layouts：支持的声道数（仅音频）
- int priv_data_size：私有数据的大小
重点介绍
- AVMediaType位于avutil.h文件内
/**
* @addtogroup lavu_media Media Type
* @brief Media Type
*/
enum AVMediaType {
AVMEDIA_TYPE_UNKNOWN = -1, ///< Usually treated as AVMEDIA_TYPE_DATA
AVMEDIA_TYPE_VIDEO,
AVMEDIA_TYPE_AUDIO,
AVMEDIA_TYPE_DATA, ///< Opaque data information usually continuous
AVMEDIA_TYPE_SUBTITLE,
AVMEDIA_TYPE_ATTACHMENT, ///< Opaque data information usually sparse
AVMEDIA_TYPE_NB
};- AVCodecID位于codec_id.h文件内
/**
* Identify the syntax and semantics of the bitstream.
* The principle is roughly:
* Two decoders with the same ID can decode the same streams.
* Two encoders with the same ID can encode compatible streams.
* There may be slight deviations from the principle due to implementation
* details.
*
* If you add a codec ID to this list, add it so that
* 1. no value of an existing codec ID changes (that would break ABI),
* 2. it is as close as possible to similar codecs
*
* After adding new codec IDs, do not forget to add an entry to the codec
* descriptor list and bump libavcodec minor version.
*/
enum AVCodecID {
AV_CODEC_ID_NONE,
/* video codecs */
AV_CODEC_ID_MPEG1VIDEO,
AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
AV_CODEC_ID_H261,
AV_CODEC_ID_H263,
AV_CODEC_ID_RV10,
AV_CODEC_ID_RV20,
AV_CODEC_ID_MJPEG,
AV_CODEC_ID_MJPEGB,
AV_CODEC_ID_LJPEG,
AV_CODEC_ID_SP5X,
AV_CODEC_ID_JPEGLS,
AV_CODEC_ID_MPEG4,
AV_CODEC_ID_RAWVIDEO,
AV_CODEC_ID_MSMPEG4V1,
AV_CODEC_ID_MSMPEG4V2,
AV_CODEC_ID_MSMPEG4V3,
AV_CODEC_ID_WMV1,
AV_CODEC_ID_WMV2,
AV_CODEC_ID_H263P,
AV_CODEC_ID_H263I,
AV_CODEC_ID_FLV1,
AV_CODEC_ID_SVQ1,
AV_CODEC_ID_SVQ3,
AV_CODEC_ID_DVVIDEO,
AV_CODEC_ID_HUFFYUV,
AV_CODEC_ID_CYUV,
AV_CODEC_ID_H264,
AV_CODEC_ID_INDEO3,
AV_CODEC_ID_VP3,
AV_CODEC_ID_THEORA,
AV_CODEC_ID_ASV1,
AV_CODEC_ID_ASV2,
AV_CODEC_ID_FFV1,
AV_CODEC_ID_4XM,
AV_CODEC_ID_VCR1,
AV_CODEC_ID_CLJR,
AV_CODEC_ID_MDEC,
AV_CODEC_ID_ROQ,
AV_CODEC_ID_INTERPLAY_VIDEO,
AV_CODEC_ID_XAN_WC3,
AV_CODEC_ID_XAN_WC4,
AV_CODEC_ID_RPZA,
AV_CODEC_ID_CINEPAK,
AV_CODEC_ID_WS_VQA,
AV_CODEC_ID_MSRLE,
AV_CODEC_ID_MSVIDEO1,
AV_CODEC_ID_IDCIN,
AV_CODEC_ID_8BPS,
AV_CODEC_ID_SMC,
AV_CODEC_ID_FLIC,
AV_CODEC_ID_TRUEMOTION1,
AV_CODEC_ID_VMDVIDEO,
AV_CODEC_ID_MSZH,
AV_CODEC_ID_ZLIB,
AV_CODEC_ID_QTRLE,
AV_CODEC_ID_TSCC,
AV_CODEC_ID_ULTI,
AV_CODEC_ID_QDRAW,
AV_CODEC_ID_VIXL,
AV_CODEC_ID_QPEG,
AV_CODEC_ID_PNG,
AV_CODEC_ID_PPM,
AV_CODEC_ID_PBM,
AV_CODEC_ID_PGM,
AV_CODEC_ID_PGMYUV,
AV_CODEC_ID_PAM,
AV_CODEC_ID_FFVHUFF,
AV_CODEC_ID_RV30,
AV_CODEC_ID_RV40,
AV_CODEC_ID_VC1,
AV_CODEC_ID_WMV3,
AV_CODEC_ID_LOCO,
AV_CODEC_ID_WNV1,
AV_CODEC_ID_AASC,
AV_CODEC_ID_INDEO2,
AV_CODEC_ID_FRAPS,
AV_CODEC_ID_TRUEMOTION2,
AV_CODEC_ID_BMP,
AV_CODEC_ID_CSCD,
AV_CODEC_ID_MMVIDEO,
AV_CODEC_ID_ZMBV,
AV_CODEC_ID_AVS,
AV_CODEC_ID_SMACKVIDEO,
AV_CODEC_ID_NUV,
AV_CODEC_ID_KMVC,
AV_CODEC_ID_FLASHSV,
AV_CODEC_ID_CAVS,
AV_CODEC_ID_JPEG2000,
AV_CODEC_ID_VMNC,
AV_CODEC_ID_VP5,
AV_CODEC_ID_VP6,
AV_CODEC_ID_VP6F,
AV_CODEC_ID_TARGA,
AV_CODEC_ID_DSICINVIDEO,
AV_CODEC_ID_TIERTEXSEQVIDEO,
AV_CODEC_ID_TIFF,
AV_CODEC_ID_GIF,
AV_CODEC_ID_DXA,
AV_CODEC_ID_DNXHD,
AV_CODEC_ID_THP,
AV_CODEC_ID_SGI,
AV_CODEC_ID_C93,
AV_CODEC_ID_BETHSOFTVID,
AV_CODEC_ID_PTX,
AV_CODEC_ID_TXD,
AV_CODEC_ID_VP6A,
AV_CODEC_ID_AMV,
AV_CODEC_ID_VB,
AV_CODEC_ID_PCX,
AV_CODEC_ID_SUNRAST,
AV_CODEC_ID_INDEO4,
AV_CODEC_ID_INDEO5,
AV_CODEC_ID_MIMIC,
AV_CODEC_ID_RL2,
AV_CODEC_ID_ESCAPE124,
AV_CODEC_ID_DIRAC,
AV_CODEC_ID_BFI,
AV_CODEC_ID_CMV,
AV_CODEC_ID_MOTIONPIXELS,
AV_CODEC_ID_TGV,
AV_CODEC_ID_TGQ,
AV_CODEC_ID_TQI,
AV_CODEC_ID_AURA,
AV_CODEC_ID_AURA2,
AV_CODEC_ID_V210X,
AV_CODEC_ID_TMV,
AV_CODEC_ID_V210,
AV_CODEC_ID_DPX,
AV_CODEC_ID_MAD,
AV_CODEC_ID_FRWU,
AV_CODEC_ID_FLASHSV2,
AV_CODEC_ID_CDGRAPHICS,
AV_CODEC_ID_R210,
AV_CODEC_ID_ANM,
AV_CODEC_ID_BINKVIDEO,
AV_CODEC_ID_IFF_ILBM,
#define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
AV_CODEC_ID_KGV1,
AV_CODEC_ID_YOP,
AV_CODEC_ID_VP8,
AV_CODEC_ID_PICTOR,
AV_CODEC_ID_ANSI,
AV_CODEC_ID_A64_MULTI,
AV_CODEC_ID_A64_MULTI5,
AV_CODEC_ID_R10K,
AV_CODEC_ID_MXPEG,
AV_CODEC_ID_LAGARITH,
AV_CODEC_ID_PRORES,
AV_CODEC_ID_JV,
AV_CODEC_ID_DFA,
AV_CODEC_ID_WMV3IMAGE,
AV_CODEC_ID_VC1IMAGE,
AV_CODEC_ID_UTVIDEO,
AV_CODEC_ID_BMV_VIDEO,
AV_CODEC_ID_VBLE,
AV_CODEC_ID_DXTORY,
AV_CODEC_ID_V410,
AV_CODEC_ID_XWD,
AV_CODEC_ID_CDXL,
AV_CODEC_ID_XBM,
AV_CODEC_ID_ZEROCODEC,
AV_CODEC_ID_MSS1,
AV_CODEC_ID_MSA1,
AV_CODEC_ID_TSCC2,
AV_CODEC_ID_MTS2,
AV_CODEC_ID_CLLC,
AV_CODEC_ID_MSS2,
AV_CODEC_ID_VP9,
AV_CODEC_ID_AIC,
AV_CODEC_ID_ESCAPE130,
AV_CODEC_ID_G2M,
AV_CODEC_ID_WEBP,
AV_CODEC_ID_HNM4_VIDEO,
AV_CODEC_ID_HEVC,
#define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
AV_CODEC_ID_FIC,
AV_CODEC_ID_ALIAS_PIX,
AV_CODEC_ID_BRENDER_PIX,
AV_CODEC_ID_PAF_VIDEO,
AV_CODEC_ID_EXR,
AV_CODEC_ID_VP7,
AV_CODEC_ID_SANM,
AV_CODEC_ID_SGIRLE,
AV_CODEC_ID_MVC1,
AV_CODEC_ID_MVC2,
AV_CODEC_ID_HQX,
AV_CODEC_ID_TDSC,
AV_CODEC_ID_HQ_HQA,
AV_CODEC_ID_HAP,
AV_CODEC_ID_DDS,
AV_CODEC_ID_DXV,
AV_CODEC_ID_SCREENPRESSO,
AV_CODEC_ID_RSCC,
AV_CODEC_ID_AVS2,
AV_CODEC_ID_PGX,
AV_CODEC_ID_AVS3,
AV_CODEC_ID_MSP2,
AV_CODEC_ID_VVC,
#define AV_CODEC_ID_H266 AV_CODEC_ID_VVC
AV_CODEC_ID_Y41P,
AV_CODEC_ID_AVRP,
AV_CODEC_ID_012V,
AV_CODEC_ID_AVUI,
AV_CODEC_ID_AYUV,
AV_CODEC_ID_TARGA_Y216,
AV_CODEC_ID_V308,
AV_CODEC_ID_V408,
AV_CODEC_ID_YUV4,
AV_CODEC_ID_AVRN,
AV_CODEC_ID_CPIA,
AV_CODEC_ID_XFACE,
AV_CODEC_ID_SNOW,
AV_CODEC_ID_SMVJPEG,
AV_CODEC_ID_APNG,
AV_CODEC_ID_DAALA,
AV_CODEC_ID_CFHD,
AV_CODEC_ID_TRUEMOTION2RT,
AV_CODEC_ID_M101,
AV_CODEC_ID_MAGICYUV,
AV_CODEC_ID_SHEERVIDEO,
AV_CODEC_ID_YLC,
AV_CODEC_ID_PSD,
AV_CODEC_ID_PIXLET,
AV_CODEC_ID_SPEEDHQ,
AV_CODEC_ID_FMVC,
AV_CODEC_ID_SCPR,
AV_CODEC_ID_CLEARVIDEO,
AV_CODEC_ID_XPM,
AV_CODEC_ID_AV1,
AV_CODEC_ID_BITPACKED,
AV_CODEC_ID_MSCC,
AV_CODEC_ID_SRGC,
AV_CODEC_ID_SVG,
AV_CODEC_ID_GDV,
AV_CODEC_ID_FITS,
AV_CODEC_ID_IMM4,
AV_CODEC_ID_PROSUMER,
AV_CODEC_ID_MWSC,
AV_CODEC_ID_WCMV,
AV_CODEC_ID_RASC,
AV_CODEC_ID_HYMT,
AV_CODEC_ID_ARBC,
AV_CODEC_ID_AGM,
AV_CODEC_ID_LSCR,
AV_CODEC_ID_VP4,
AV_CODEC_ID_IMM5,
AV_CODEC_ID_MVDV,
AV_CODEC_ID_MVHA,
AV_CODEC_ID_CDTOONS,
AV_CODEC_ID_MV30,
AV_CODEC_ID_NOTCHLC,
AV_CODEC_ID_PFM,
AV_CODEC_ID_MOBICLIP,
AV_CODEC_ID_PHOTOCD,
AV_CODEC_ID_IPU,
AV_CODEC_ID_ARGO,
AV_CODEC_ID_CRI,
AV_CODEC_ID_SIMBIOSIS_IMX,
AV_CODEC_ID_SGA_VIDEO,
AV_CODEC_ID_GEM,
AV_CODEC_ID_VBN,
AV_CODEC_ID_JPEGXL,
AV_CODEC_ID_QOI,
/* various PCM "codecs" */
AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
AV_CODEC_ID_PCM_S16LE = 0x10000,
AV_CODEC_ID_PCM_S16BE,
AV_CODEC_ID_PCM_U16LE,
AV_CODEC_ID_PCM_U16BE,
AV_CODEC_ID_PCM_S8,
AV_CODEC_ID_PCM_U8,
AV_CODEC_ID_PCM_MULAW,
AV_CODEC_ID_PCM_ALAW,
AV_CODEC_ID_PCM_S32LE,
AV_CODEC_ID_PCM_S32BE,
AV_CODEC_ID_PCM_U32LE,
AV_CODEC_ID_PCM_U32BE,
AV_CODEC_ID_PCM_S24LE,
AV_CODEC_ID_PCM_S24BE,
AV_CODEC_ID_PCM_U24LE,
AV_CODEC_ID_PCM_U24BE,
AV_CODEC_ID_PCM_S24DAUD,
AV_CODEC_ID_PCM_ZORK,
AV_CODEC_ID_PCM_S16LE_PLANAR,
AV_CODEC_ID_PCM_DVD,
AV_CODEC_ID_PCM_F32BE,
AV_CODEC_ID_PCM_F32LE,
AV_CODEC_ID_PCM_F64BE,
AV_CODEC_ID_PCM_F64LE,
AV_CODEC_ID_PCM_BLURAY,
AV_CODEC_ID_PCM_LXF,
AV_CODEC_ID_S302M,
AV_CODEC_ID_PCM_S8_PLANAR,
AV_CODEC_ID_PCM_S24LE_PLANAR,
AV_CODEC_ID_PCM_S32LE_PLANAR,
AV_CODEC_ID_PCM_S16BE_PLANAR,
AV_CODEC_ID_PCM_S64LE,
AV_CODEC_ID_PCM_S64BE,
AV_CODEC_ID_PCM_F16LE,
AV_CODEC_ID_PCM_F24LE,
AV_CODEC_ID_PCM_VIDC,
AV_CODEC_ID_PCM_SGA,
/* various ADPCM codecs */
AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
AV_CODEC_ID_ADPCM_IMA_WAV,
AV_CODEC_ID_ADPCM_IMA_DK3,
AV_CODEC_ID_ADPCM_IMA_DK4,
AV_CODEC_ID_ADPCM_IMA_WS,
AV_CODEC_ID_ADPCM_IMA_SMJPEG,
AV_CODEC_ID_ADPCM_MS,
AV_CODEC_ID_ADPCM_4XM,
AV_CODEC_ID_ADPCM_XA,
AV_CODEC_ID_ADPCM_ADX,
AV_CODEC_ID_ADPCM_EA,
AV_CODEC_ID_ADPCM_G726,
AV_CODEC_ID_ADPCM_CT,
AV_CODEC_ID_ADPCM_SWF,
AV_CODEC_ID_ADPCM_YAMAHA,
AV_CODEC_ID_ADPCM_SBPRO_4,
AV_CODEC_ID_ADPCM_SBPRO_3,
AV_CODEC_ID_ADPCM_SBPRO_2,
AV_CODEC_ID_ADPCM_THP,
AV_CODEC_ID_ADPCM_IMA_AMV,
AV_CODEC_ID_ADPCM_EA_R1,
AV_CODEC_ID_ADPCM_EA_R3,
AV_CODEC_ID_ADPCM_EA_R2,
AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
AV_CODEC_ID_ADPCM_IMA_EA_EACS,
AV_CODEC_ID_ADPCM_EA_XAS,
AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
AV_CODEC_ID_ADPCM_IMA_ISS,
AV_CODEC_ID_ADPCM_G722,
AV_CODEC_ID_ADPCM_IMA_APC,
AV_CODEC_ID_ADPCM_VIMA,
AV_CODEC_ID_ADPCM_AFC,
AV_CODEC_ID_ADPCM_IMA_OKI,
AV_CODEC_ID_ADPCM_DTK,
AV_CODEC_ID_ADPCM_IMA_RAD,
AV_CODEC_ID_ADPCM_G726LE,
AV_CODEC_ID_ADPCM_THP_LE,
AV_CODEC_ID_ADPCM_PSX,
AV_CODEC_ID_ADPCM_AICA,
AV_CODEC_ID_ADPCM_IMA_DAT4,
AV_CODEC_ID_ADPCM_MTAF,
AV_CODEC_ID_ADPCM_AGM,
AV_CODEC_ID_ADPCM_ARGO,
AV_CODEC_ID_ADPCM_IMA_SSI,
AV_CODEC_ID_ADPCM_ZORK,
AV_CODEC_ID_ADPCM_IMA_APM,
AV_CODEC_ID_ADPCM_IMA_ALP,
AV_CODEC_ID_ADPCM_IMA_MTF,
AV_CODEC_ID_ADPCM_IMA_CUNNING,
AV_CODEC_ID_ADPCM_IMA_MOFLEX,
AV_CODEC_ID_ADPCM_IMA_ACORN,
/* AMR */
AV_CODEC_ID_AMR_NB = 0x12000,
AV_CODEC_ID_AMR_WB,
/* RealAudio codecs*/
AV_CODEC_ID_RA_144 = 0x13000,
AV_CODEC_ID_RA_288,
/* various DPCM codecs */
AV_CODEC_ID_ROQ_DPCM = 0x14000,
AV_CODEC_ID_INTERPLAY_DPCM,
AV_CODEC_ID_XAN_DPCM,
AV_CODEC_ID_SOL_DPCM,
AV_CODEC_ID_SDX2_DPCM,
AV_CODEC_ID_GREMLIN_DPCM,
AV_CODEC_ID_DERF_DPCM,
/* audio codecs */
AV_CODEC_ID_MP2 = 0x15000,
AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
AV_CODEC_ID_AAC,
AV_CODEC_ID_AC3,
AV_CODEC_ID_DTS,
AV_CODEC_ID_VORBIS,
AV_CODEC_ID_DVAUDIO,
AV_CODEC_ID_WMAV1,
AV_CODEC_ID_WMAV2,
AV_CODEC_ID_MACE3,
AV_CODEC_ID_MACE6,
AV_CODEC_ID_VMDAUDIO,
AV_CODEC_ID_FLAC,
AV_CODEC_ID_MP3ADU,
AV_CODEC_ID_MP3ON4,
AV_CODEC_ID_SHORTEN,
AV_CODEC_ID_ALAC,
AV_CODEC_ID_WESTWOOD_SND1,
AV_CODEC_ID_GSM, ///< as in Berlin toast format
AV_CODEC_ID_QDM2,
AV_CODEC_ID_COOK,
AV_CODEC_ID_TRUESPEECH,
AV_CODEC_ID_TTA,
AV_CODEC_ID_SMACKAUDIO,
AV_CODEC_ID_QCELP,
AV_CODEC_ID_WAVPACK,
AV_CODEC_ID_DSICINAUDIO,
AV_CODEC_ID_IMC,
AV_CODEC_ID_MUSEPACK7,
AV_CODEC_ID_MLP,
AV_CODEC_ID_GSM_MS, /* as found in WAV */
AV_CODEC_ID_ATRAC3,
AV_CODEC_ID_APE,
AV_CODEC_ID_NELLYMOSER,
AV_CODEC_ID_MUSEPACK8,
AV_CODEC_ID_SPEEX,
AV_CODEC_ID_WMAVOICE,
AV_CODEC_ID_WMAPRO,
AV_CODEC_ID_WMALOSSLESS,
AV_CODEC_ID_ATRAC3P,
AV_CODEC_ID_EAC3,
AV_CODEC_ID_SIPR,
AV_CODEC_ID_MP1,
AV_CODEC_ID_TWINVQ,
AV_CODEC_ID_TRUEHD,
AV_CODEC_ID_MP4ALS,
AV_CODEC_ID_ATRAC1,
AV_CODEC_ID_BINKAUDIO_RDFT,
AV_CODEC_ID_BINKAUDIO_DCT,
AV_CODEC_ID_AAC_LATM,
AV_CODEC_ID_QDMC,
AV_CODEC_ID_CELT,
AV_CODEC_ID_G723_1,
AV_CODEC_ID_G729,
AV_CODEC_ID_8SVX_EXP,
AV_CODEC_ID_8SVX_FIB,
AV_CODEC_ID_BMV_AUDIO,
AV_CODEC_ID_RALF,
AV_CODEC_ID_IAC,
AV_CODEC_ID_ILBC,
AV_CODEC_ID_OPUS,
AV_CODEC_ID_COMFORT_NOISE,
AV_CODEC_ID_TAK,
AV_CODEC_ID_METASOUND,
AV_CODEC_ID_PAF_AUDIO,
AV_CODEC_ID_ON2AVC,
AV_CODEC_ID_DSS_SP,
AV_CODEC_ID_CODEC2,
AV_CODEC_ID_FFWAVESYNTH,
AV_CODEC_ID_SONIC,
AV_CODEC_ID_SONIC_LS,
AV_CODEC_ID_EVRC,
AV_CODEC_ID_SMV,
AV_CODEC_ID_DSD_LSBF,
AV_CODEC_ID_DSD_MSBF,
AV_CODEC_ID_DSD_LSBF_PLANAR,
AV_CODEC_ID_DSD_MSBF_PLANAR,
AV_CODEC_ID_4GV,
AV_CODEC_ID_INTERPLAY_ACM,
AV_CODEC_ID_XMA1,
AV_CODEC_ID_XMA2,
AV_CODEC_ID_DST,
AV_CODEC_ID_ATRAC3AL,
AV_CODEC_ID_ATRAC3PAL,
AV_CODEC_ID_DOLBY_E,
AV_CODEC_ID_APTX,
AV_CODEC_ID_APTX_HD,
AV_CODEC_ID_SBC,
AV_CODEC_ID_ATRAC9,
AV_CODEC_ID_HCOM,
AV_CODEC_ID_ACELP_KELVIN,
AV_CODEC_ID_MPEGH_3D_AUDIO,
AV_CODEC_ID_SIREN,
AV_CODEC_ID_HCA,
AV_CODEC_ID_FASTAUDIO,
AV_CODEC_ID_MSNSIREN,
AV_CODEC_ID_DFPWM,
/* subtitle codecs */
AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
AV_CODEC_ID_DVB_SUBTITLE,
AV_CODEC_ID_TEXT, ///< raw UTF-8 text
AV_CODEC_ID_XSUB,
AV_CODEC_ID_SSA,
AV_CODEC_ID_MOV_TEXT,
AV_CODEC_ID_HDMV_PGS_SUBTITLE,
AV_CODEC_ID_DVB_TELETEXT,
AV_CODEC_ID_SRT,
AV_CODEC_ID_MICRODVD,
AV_CODEC_ID_EIA_608,
AV_CODEC_ID_JACOSUB,
AV_CODEC_ID_SAMI,
AV_CODEC_ID_REALTEXT,
AV_CODEC_ID_STL,
AV_CODEC_ID_SUBVIEWER1,
AV_CODEC_ID_SUBVIEWER,
AV_CODEC_ID_SUBRIP,
AV_CODEC_ID_WEBVTT,
AV_CODEC_ID_MPL2,
AV_CODEC_ID_VPLAYER,
AV_CODEC_ID_PJS,
AV_CODEC_ID_ASS,
AV_CODEC_ID_HDMV_TEXT_SUBTITLE,
AV_CODEC_ID_TTML,
AV_CODEC_ID_ARIB_CAPTION,
/* other specific kind of codecs (generally used for attachments) */
AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
AV_CODEC_ID_TTF = 0x18000,
AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
AV_CODEC_ID_EPG,
AV_CODEC_ID_BINTEXT,
AV_CODEC_ID_XBIN,
AV_CODEC_ID_IDF,
AV_CODEC_ID_OTF,
AV_CODEC_ID_SMPTE_KLV,
AV_CODEC_ID_DVD_NAV,
AV_CODEC_ID_TIMED_ID3,
AV_CODEC_ID_BIN_DATA,
AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
* stream (only used by libavformat) */
AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
* stream (only used by libavformat) */
AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
};- AVCodecID 位于 codec_id.h文件内
/**
* Identify the syntax and semantics of the bitstream.
* The principle is roughly:
* Two decoders with the same ID can decode the same streams.
* Two encoders with the same ID can encode compatible streams.
* There may be slight deviations from the principle due to implementation
* details.
*
* If you add a codec ID to this list, add it so that
* 1. no value of an existing codec ID changes (that would break ABI),
* 2. it is as close as possible to similar codecs
*
* After adding new codec IDs, do not forget to add an entry to the codec
* descriptor list and bump libavcodec minor version.
*/
enum AVCodecID {
AV_CODEC_ID_NONE,
/* video codecs */
AV_CODEC_ID_MPEG1VIDEO,
AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
AV_CODEC_ID_H261,
AV_CODEC_ID_H263,
AV_CODEC_ID_RV10,
AV_CODEC_ID_RV20,
AV_CODEC_ID_MJPEG,
AV_CODEC_ID_MJPEGB,
AV_CODEC_ID_LJPEG,
AV_CODEC_ID_SP5X,
AV_CODEC_ID_JPEGLS,
AV_CODEC_ID_MPEG4,
AV_CODEC_ID_RAWVIDEO,
AV_CODEC_ID_MSMPEG4V1,
AV_CODEC_ID_MSMPEG4V2,
AV_CODEC_ID_MSMPEG4V3,
AV_CODEC_ID_WMV1,
AV_CODEC_ID_WMV2,
AV_CODEC_ID_H263P,
AV_CODEC_ID_H263I,
AV_CODEC_ID_FLV1,
AV_CODEC_ID_SVQ1,
AV_CODEC_ID_SVQ3,
AV_CODEC_ID_DVVIDEO,
AV_CODEC_ID_HUFFYUV,
AV_CODEC_ID_CYUV,
AV_CODEC_ID_H264,
AV_CODEC_ID_INDEO3,
AV_CODEC_ID_VP3,
AV_CODEC_ID_THEORA,
AV_CODEC_ID_ASV1,
AV_CODEC_ID_ASV2,
AV_CODEC_ID_FFV1,
AV_CODEC_ID_4XM,
AV_CODEC_ID_VCR1,
AV_CODEC_ID_CLJR,
AV_CODEC_ID_MDEC,
AV_CODEC_ID_ROQ,
AV_CODEC_ID_INTERPLAY_VIDEO,
AV_CODEC_ID_XAN_WC3,
AV_CODEC_ID_XAN_WC4,
AV_CODEC_ID_RPZA,
AV_CODEC_ID_CINEPAK,
AV_CODEC_ID_WS_VQA,
AV_CODEC_ID_MSRLE,
AV_CODEC_ID_MSVIDEO1,
AV_CODEC_ID_IDCIN,
AV_CODEC_ID_8BPS,
AV_CODEC_ID_SMC,
此处省略 几百行
}- AVPixelFormat位于pixfmt.h文件内
/**
* Pixel format.
*
* @note
* AV_PIX_FMT_RGB32 is handled in an endian-specific manner. An RGBA
* color is put together as:
* (A << 24) | (R << 16) | (G << 8) | B
* This is stored as BGRA on little-endian CPU architectures and ARGB on
* big-endian CPUs.
*
* @note
* If the resolution is not a multiple of the chroma subsampling factor
* then the chroma plane resolution must be rounded up.
*
* @par
* When the pixel format is palettized RGB32 (AV_PIX_FMT_PAL8), the palettized
* image data is stored in AVFrame.data[0]. The palette is transported in
* AVFrame.data[1], is 1024 bytes long (256 4-byte entries) and is
* formatted the same as in AV_PIX_FMT_RGB32 described above (i.e., it is
* also endian-specific). Note also that the individual RGB32 palette
* components stored in AVFrame.data[1] should be in the range 0..255.
* This is important as many custom PAL8 video codecs that were designed
* to run on the IBM VGA graphics adapter use 6-bit palette components.
*
* @par
* For all the 8 bits per pixel formats, an RGB32 palette is in data[1] like
* for pal8. This palette is filled in automatically by the function
* allocating the picture.
*/
enum AVPixelFormat {
AV_PIX_FMT_NONE = -1,
AV_PIX_FMT_YUV420P, ///< planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
AV_PIX_FMT_YUYV422, ///< packed YUV 4:2:2, 16bpp, Y0 Cb Y1 Cr
AV_PIX_FMT_RGB24, ///< packed RGB 8:8:8, 24bpp, RGBRGB...
AV_PIX_FMT_BGR24, ///< packed RGB 8:8:8, 24bpp, BGRBGR...
AV_PIX_FMT_YUV422P, ///< planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
AV_PIX_FMT_YUV444P, ///< planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
AV_PIX_FMT_YUV410P, ///< planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
AV_PIX_FMT_YUV411P, ///< planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
AV_PIX_FMT_GRAY8, ///< Y , 8bpp
AV_PIX_FMT_MONOWHITE, ///< Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb
AV_PIX_FMT_MONOBLACK, ///< Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb
AV_PIX_FMT_PAL8, ///< 8 bits with AV_PIX_FMT_RGB32 palette
AV_PIX_FMT_YUVJ420P, ///< planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting color_range
AV_PIX_FMT_YUVJ422P, ///< planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting color_range
AV_PIX_FMT_YUVJ444P, ///< planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting color_range
AV_PIX_FMT_UYVY422, ///< packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
AV_PIX_FMT_UYYVYY411, ///< packed YUV 4:1:1, 12bpp, Cb Y0 Y1 Cr Y2 Y3
AV_PIX_FMT_BGR8, ///< packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
AV_PIX_FMT_BGR4, ///< packed RGB 1:2:1 bitstream, 4bpp, (msb)1B 2G 1R(lsb), a byte contains two pixels, the first pixel in the byte is the one composed by the 4 msb bits
AV_PIX_FMT_BGR4_BYTE, ///< packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
AV_PIX_FMT_RGB8, ///< packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
AV_PIX_FMT_RGB4, ///< packed RGB 1:2:1 bitstream, 4bpp, (msb)1R 2G 1B(lsb), a byte contains two pixels, the first pixel in the byte is the one composed by the 4 msb bits
AV_PIX_FMT_RGB4_BYTE, ///< packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
AV_PIX_FMT_NV12, ///< planar YUV 4:2:0, 12bpp, 1 plane for Y and 1 plane for the UV components, which are interleaved (first byte U and the following byte V)
AV_PIX_FMT_NV21, ///< as above, but U and V bytes are swapped
AV_PIX_FMT_ARGB, ///< packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
AV_PIX_FMT_RGBA, ///< packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
AV_PIX_FMT_ABGR, ///< packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
AV_PIX_FMT_BGRA, ///< packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
AV_PIX_FMT_GRAY16BE, ///< Y , 16bpp, big-endian
AV_PIX_FMT_GRAY16LE, ///< Y , 16bpp, little-endian
AV_PIX_FMT_YUV440P, ///< planar YUV 4:4:0 (1 Cr & Cb sample per 1x2 Y samples)
AV_PIX_FMT_YUVJ440P, ///< planar YUV 4:4:0 full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV440P and setting color_range
AV_PIX_FMT_YUVA420P, ///< planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
AV_PIX_FMT_RGB48BE, ///< packed RGB 16:16:16, 48bpp, 16R, 16G, 16B, the 2-byte value for each R/G/B component is stored as big-endian
AV_PIX_FMT_RGB48LE, ///< packed RGB 16:16:16, 48bpp, 16R, 16G, 16B, the 2-byte value for each R/G/B component is stored as little-endian
AV_PIX_FMT_RGB565BE, ///< packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), big-endian
AV_PIX_FMT_RGB565LE, ///< packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), little-endian
AV_PIX_FMT_RGB555BE, ///< packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), big-endian , X=unused/undefined
AV_PIX_FMT_RGB555LE, ///< packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_BGR565BE, ///< packed BGR 5:6:5, 16bpp, (msb) 5B 6G 5R(lsb), big-endian
AV_PIX_FMT_BGR565LE, ///< packed BGR 5:6:5, 16bpp, (msb) 5B 6G 5R(lsb), little-endian
AV_PIX_FMT_BGR555BE, ///< packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), big-endian , X=unused/undefined
AV_PIX_FMT_BGR555LE, ///< packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), little-endian, X=unused/undefined
/**
* Hardware acceleration through VA-API, data[3] contains a
* VASurfaceID.
*/
AV_PIX_FMT_VAAPI,
AV_PIX_FMT_YUV420P16LE, ///< planar YUV 4:2:0, 24bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV420P16BE, ///< planar YUV 4:2:0, 24bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV422P16LE, ///< planar YUV 4:2:2, 32bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_YUV422P16BE, ///< planar YUV 4:2:2, 32bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV444P16LE, ///< planar YUV 4:4:4, 48bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_YUV444P16BE, ///< planar YUV 4:4:4, 48bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_DXVA2_VLD, ///< HW decoding through DXVA2, Picture.data[3] contains a LPDIRECT3DSURFACE9 pointer
AV_PIX_FMT_RGB444LE, ///< packed RGB 4:4:4, 16bpp, (msb)4X 4R 4G 4B(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_RGB444BE, ///< packed RGB 4:4:4, 16bpp, (msb)4X 4R 4G 4B(lsb), big-endian, X=unused/undefined
AV_PIX_FMT_BGR444LE, ///< packed BGR 4:4:4, 16bpp, (msb)4X 4B 4G 4R(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_BGR444BE, ///< packed BGR 4:4:4, 16bpp, (msb)4X 4B 4G 4R(lsb), big-endian, X=unused/undefined
AV_PIX_FMT_YA8, ///< 8 bits gray, 8 bits alpha
AV_PIX_FMT_Y400A = AV_PIX_FMT_YA8, ///< alias for AV_PIX_FMT_YA8
AV_PIX_FMT_GRAY8A= AV_PIX_FMT_YA8, ///< alias for AV_PIX_FMT_YA8
此处省略 几百行
}- AVSampleFormat 位于samplefmt.h文件中
/**
* Audio sample formats
*
* - The data described by the sample format is always in native-endian order.
* Sample values can be expressed by native C types, hence the lack of a signed
* 24-bit sample format even though it is a common raw audio data format.
*
* - The floating-point formats are based on full volume being in the range
* [-1.0, 1.0]. Any values outside this range are beyond full volume level.
*
* - The data layout as used in av_samples_fill_arrays() and elsewhere in FFmpeg
* (such as AVFrame in libavcodec) is as follows:
*
* @par
* For planar sample formats, each audio channel is in a separate data plane,
* and linesize is the buffer size, in bytes, for a single plane. All data
* planes must be the same size. For packed sample formats, only the first data
* plane is used, and samples for each channel are interleaved. In this case,
* linesize is the buffer size, in bytes, for the 1 plane.
*
*/
enum AVSampleFormat {
AV_SAMPLE_FMT_NONE = -1,
AV_SAMPLE_FMT_U8, ///< unsigned 8 bits
AV_SAMPLE_FMT_S16, ///< signed 16 bits
AV_SAMPLE_FMT_S32, ///< signed 32 bits
AV_SAMPLE_FMT_FLT, ///< float
AV_SAMPLE_FMT_DBL, ///< double
AV_SAMPLE_FMT_U8P, ///< unsigned 8 bits, planar
AV_SAMPLE_FMT_S16P, ///< signed 16 bits, planar
AV_SAMPLE_FMT_S32P, ///< signed 32 bits, planar
AV_SAMPLE_FMT_FLTP, ///< float, planar
AV_SAMPLE_FMT_DBLP, ///< double, planar
AV_SAMPLE_FMT_S64, ///< signed 64 bits
AV_SAMPLE_FMT_S64P, ///< signed 64 bits, planar
AV_SAMPLE_FMT_NB ///< Number of sample formats. DO NOT USE if linking dynamically
};
- 每一个编解码器对应一个结构体
- H.264解码器的结构体如下所示（h264dec.c）
const FFCodec ff_h264_decoder = {
.p.name = "h264",
.p.long_name = NULL_IF_CONFIG_SMALL("H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_H264,
.priv_data_size = sizeof(H264Context),
.init = h264_decode_init,
.close = h264_decode_end,
FF_CODEC_DECODE_CB(h264_decode_frame),
.p.capabilities = /*AV_CODEC_CAP_DRAW_HORIZ_BAND |*/ AV_CODEC_CAP_DR1 |
AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS |
AV_CODEC_CAP_FRAME_THREADS,
.hw_configs = (const AVCodecHWConfigInternal *const []) {
#if CONFIG_H264_DXVA2_HWACCEL
HWACCEL_DXVA2(h264),
#endif
#if CONFIG_H264_D3D11VA_HWACCEL
HWACCEL_D3D11VA(h264),
#endif
#if CONFIG_H264_D3D11VA2_HWACCEL
HWACCEL_D3D11VA2(h264),
#endif
#if CONFIG_H264_NVDEC_HWACCEL
HWACCEL_NVDEC(h264),
#endif
#if CONFIG_H264_VAAPI_HWACCEL
HWACCEL_VAAPI(h264),
#endif
#if CONFIG_H264_VDPAU_HWACCEL
HWACCEL_VDPAU(h264),
#endif
#if CONFIG_H264_VIDEOTOOLBOX_HWACCEL
HWACCEL_VIDEOTOOLBOX(h264),
#endif
NULL
},
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_EXPORTS_CROPPING |
FF_CODEC_CAP_ALLOCATE_PROGRESS | FF_CODEC_CAP_INIT_CLEANUP,
.flush = h264_decode_flush,
.update_thread_context = ONLY_IF_THREADS_ENABLED(ff_h264_update_thread_context),
.update_thread_context_for_user = ONLY_IF_THREADS_ENABLED(ff_h264_update_thread_context_for_user),
.p.profiles = NULL_IF_CONFIG_SMALL(ff_h264_profiles),
.p.priv_class = &h264_class,
};
- JPEG2000解码器结构体位于jpeg2000dec.c
const FFCodec ff_jpeg2000_decoder = {
.p.name = "jpeg2000",
.p.long_name = NULL_IF_CONFIG_SMALL("JPEG 2000"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_JPEG2000,
.p.capabilities = AV_CODEC_CAP_SLICE_THREADS | AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_DR1,
.priv_data_size = sizeof(Jpeg2000DecoderContext),
.init = jpeg2000_decode_init,
FF_CODEC_DECODE_CB(jpeg2000_decode_frame),
.p.priv_class = &jpeg2000_class,
.p.max_lowres = 5,
.p.profiles = NULL_IF_CONFIG_SMALL(ff_jpeg2000_profiles),
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
- 以下内容最新版 已经删除
下面简单介绍一下遍历ffmpeg中的解码器信息的方法（这些解码器以一个链表的形式存储）：
1.注册所有编解码器：av_register_all();
2.声明一个AVCodec类型的指针，比如说AVCodec* first_c;
3.调用av_codec_next()函数，即可获得指向链表下一个解码器的指针，循环往复可以获得所有解码器的信息。注意，如果想要获得指向第一个解码器的指针，则需要将该函数的参数设置为NULL。代码
typedef struct AVCodec {
/**
* Name of the codec implementation. //编解码器实现的名称
* The name is globally unique among encoders and among decoders (but an
* encoder and a decoder can share the same name).
* //名称在编码器和解码器之间是全局唯一的（但编码器和解码器可以共享相同的名称）
* This is the primary way to find a codec from the user perspective.
* //这是从用户角度查找编解码器的主要方式
*/
const char *name;
/**
* Descriptive name for the codec, meant to be more human readable than name.//编解码器的描述性名称，意味着比名称更易于阅读
* You should use the NULL_IF_CONFIG_SMALL() macro to define it. //您应该使用 NULL_IF_CONFIG_SMALL() 宏来定义它
*/
const char *long_name;
enum AVMediaType type;
enum AVCodecID id;
/**
* Codec capabilities. //编解码器功能
* see AV_CODEC_CAP_*
*/
int capabilities;
uint8_t max_lowres; ///< maximum value for lowres supported by the decoder //解码器支持的低分辨率最大值
const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0} //支持的帧率数组，如果有，则为 NULL，数组由 {0,0} 终止
const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1 //支持的像素格式数组，如果未知，则为 NULL，数组由 -1 终止
const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0 //支持的音频采样率数组，如果未知，则为 NULL，数组以 0 终止
const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1 //支持的样本格式数组，如果未知，则为 NULL，数组以 -1 终止
#if FF_API_OLD_CHANNEL_LAYOUT
/**
* @deprecated use ch_layouts instead //改用 ch_layouts
*/
attribute_deprecated
const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0 //支持通道布局的数组，如果未知，则为 NULL。 数组以 0 结束
#endif
const AVClass *priv_class; ///< AVClass for the private context //私有上下文的 AVClass
const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
///已识别配置文件的数组，如果未知，则为 NULL，数组由 {FF_PROFILE_UNKNOWN} 终止
/**
* Group name of the codec implementation. //编解码器实现的组名
* This is a short symbolic name of the wrapper backing this codec. A
* wrapper uses some kind of external implementation for the codec, such
* as an external library, or a codec implementation provided by the OS or
* the hardware.
* 这是支持此编解码器的包装器的简短符号名称。包装器为编解码器使用某种外部实现，
* 例如外部库，或者由操作系统或硬件提供的编解码器实现
*
* If this field is NULL, this is a builtin, libavcodec native codec.
* If non-NULL, this will be the suffix in AVCodec.name in most cases
* (usually AVCodec.name will be of the form "_").
* 如果此字段为 NULL，则这是一个内置的 libavcodec 本机编解码器
* 如果非 NULL，在大多数情况下，这将是 AVCodec.name 中的后缀（通常 AVCodec.name
* 的格式为“_”）
*/
const char *wrapper_name;
/**
* Array of supported channel layouts, terminated with a zeroed layout.
* 支持的通道布局数组，以归零布局终止
*/
const AVChannelLayout *ch_layouts;
} AVCodec;