mm7: lib/libavcodec/avcodec.h comparison

comparison lib/libavcodec/avcodec.h @ 2134:992d2e6f907d

preparation for libavcodec

author	zipi
date	Tue, 31 Dec 2013 14:52:14 +0000
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comparison

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-:e378232bfd36
+:992d2e6f907d
+/*
+* copyright (c) 2001 Fabrice Bellard
+*
+* This file is part of FFmpeg.
+*
+* FFmpeg is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation; either
+* version 2.1 of the License, or (at your option) any later version.
+*
+* FFmpeg is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with FFmpeg; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+*/
+#ifndef AVCODEC_AVCODEC_H
+#define AVCODEC_AVCODEC_H
+/**
+* @file
+* @ingroup libavc
+* Libavcodec external API header
+*/
+#include <errno.h>
+#include "../libavutil/samplefmt.h"
+#include "../libavutil/avutil.h"
+#include "../libavutil/buffer.h"
+#include "../libavutil/cpu.h"
+#include "../libavutil/channel_layout.h"
+#include "../libavutil/dict.h"
+#include "../libavutil/frame.h"
+#include "../libavutil/log.h"
+#include "../libavutil/pixfmt.h"
+#include "../libavutil/rational.h"
+#include "../libavcodec/version.h"
+/**
+* @defgroup libavc Encoding/Decoding Library
+* @{
+*
+* @defgroup lavc_decoding Decoding
+* @{
+* @}
+*
+* @defgroup lavc_encoding Encoding
+* @{
+* @}
+*
+* @defgroup lavc_codec Codecs
+* @{
+* @defgroup lavc_codec_native Native Codecs
+* @{
+* @}
+* @defgroup lavc_codec_wrappers External library wrappers
+* @{
+* @}
+* @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
+* @{
+* @}
+* @}
+* @defgroup lavc_internal Internal
+* @{
+* @}
+* @}
+*
+*/
+/**
+* @defgroup lavc_core Core functions/structures.
+* @ingroup libavc
+*
+* Basic definitions, functions for querying libavcodec capabilities,
+* allocating core structures, etc.
+* @{
+*/
+/**
+* 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 a existing codec ID changes (that would break ABI),
+* 2. Give it a value which when taken as ASCII is recognized uniquely by a human as this specific codec.
+*    This ensures that 2 forks can independently add AVCodecIDs without producing conflicts.
+*
+* 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_MPEG2VIDEO_XVMC,
+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,
+AV_CODEC_ID_IFF_BYTERUN1,
+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_DEPRECATED,
+AV_CODEC_ID_BRENDER_PIX= MKBETAG('B','P','I','X'),
+AV_CODEC_ID_Y41P       = MKBETAG('Y','4','1','P'),
+AV_CODEC_ID_ESCAPE130  = MKBETAG('E','1','3','0'),
+AV_CODEC_ID_EXR        = MKBETAG('0','E','X','R'),
+AV_CODEC_ID_AVRP       = MKBETAG('A','V','R','P'),
+AV_CODEC_ID_012V       = MKBETAG('0','1','2','V'),
+AV_CODEC_ID_G2M        = MKBETAG( 0 ,'G','2','M'),
+AV_CODEC_ID_AVUI       = MKBETAG('A','V','U','I'),
+AV_CODEC_ID_AYUV       = MKBETAG('A','Y','U','V'),
+AV_CODEC_ID_TARGA_Y216 = MKBETAG('T','2','1','6'),
+AV_CODEC_ID_V308       = MKBETAG('V','3','0','8'),
+AV_CODEC_ID_V408       = MKBETAG('V','4','0','8'),
+AV_CODEC_ID_YUV4       = MKBETAG('Y','U','V','4'),
+AV_CODEC_ID_SANM       = MKBETAG('S','A','N','M'),
+AV_CODEC_ID_PAF_VIDEO  = MKBETAG('P','A','F','V'),
+AV_CODEC_ID_AVRN       = MKBETAG('A','V','R','n'),
+AV_CODEC_ID_CPIA       = MKBETAG('C','P','I','A'),
+AV_CODEC_ID_XFACE      = MKBETAG('X','F','A','C'),
+AV_CODEC_ID_SGIRLE     = MKBETAG('S','G','I','R'),
+AV_CODEC_ID_MVC1       = MKBETAG('M','V','C','1'),
+AV_CODEC_ID_MVC2       = MKBETAG('M','V','C','2'),
+AV_CODEC_ID_SNOW       = MKBETAG('S','N','O','W'),
+AV_CODEC_ID_WEBP       = MKBETAG('W','E','B','P'),
+AV_CODEC_ID_SMVJPEG    = MKBETAG('S','M','V','J'),
+/* 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 = MKBETAG(24,'P','S','P'),
+AV_CODEC_ID_PCM_S32LE_PLANAR = MKBETAG(32,'P','S','P'),
+AV_CODEC_ID_PCM_S16BE_PLANAR = MKBETAG('P','S','P',16),
+/* 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_VIMA       = MKBETAG('V','I','M','A'),
+AV_CODEC_ID_ADPCM_AFC  = MKBETAG('A','F','C',' '),
+AV_CODEC_ID_ADPCM_IMA_OKI = MKBETAG('O','K','I',' '),
+AV_CODEC_ID_ADPCM_DTK  = MKBETAG('D','T','K',' '),
+AV_CODEC_ID_ADPCM_IMA_RAD = MKBETAG('R','A','D',' '),
+/* 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,
+/* 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_VOXWARE,
+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_DEPRECATED,
+AV_CODEC_ID_COMFORT_NOISE,
+AV_CODEC_ID_TAK_DEPRECATED,
+AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
+AV_CODEC_ID_SONIC       = MKBETAG('S','O','N','C'),
+AV_CODEC_ID_SONIC_LS    = MKBETAG('S','O','N','L'),
+AV_CODEC_ID_PAF_AUDIO   = MKBETAG('P','A','F','A'),
+AV_CODEC_ID_OPUS        = MKBETAG('O','P','U','S'),
+AV_CODEC_ID_TAK         = MKBETAG('t','B','a','K'),
+AV_CODEC_ID_EVRC        = MKBETAG('s','e','v','c'),
+AV_CODEC_ID_SMV         = MKBETAG('s','s','m','v'),
+/* 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   = MKBETAG('m','D','V','D'),
+AV_CODEC_ID_EIA_608    = MKBETAG('c','6','0','8'),
+AV_CODEC_ID_JACOSUB    = MKBETAG('J','S','U','B'),
+AV_CODEC_ID_SAMI       = MKBETAG('S','A','M','I'),
+AV_CODEC_ID_REALTEXT   = MKBETAG('R','T','X','T'),
+AV_CODEC_ID_SUBVIEWER1 = MKBETAG('S','b','V','1'),
+AV_CODEC_ID_SUBVIEWER  = MKBETAG('S','u','b','V'),
+AV_CODEC_ID_SUBRIP     = MKBETAG('S','R','i','p'),
+AV_CODEC_ID_WEBVTT     = MKBETAG('W','V','T','T'),
+AV_CODEC_ID_MPL2       = MKBETAG('M','P','L','2'),
+AV_CODEC_ID_VPLAYER    = MKBETAG('V','P','l','r'),
+AV_CODEC_ID_PJS        = MKBETAG('P','h','J','S'),
+AV_CODEC_ID_ASS        = MKBETAG('A','S','S',' '),  ///< ASS as defined in Matroska
+/* 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_BINTEXT    = MKBETAG('B','T','X','T'),
+AV_CODEC_ID_XBIN       = MKBETAG('X','B','I','N'),
+AV_CODEC_ID_IDF        = MKBETAG( 0 ,'I','D','F'),
+AV_CODEC_ID_OTF        = MKBETAG( 0 ,'O','T','F'),
+AV_CODEC_ID_SMPTE_KLV  = MKBETAG('K','L','V','A'),
+AV_CODEC_ID_DVD_NAV    = MKBETAG('D','N','A','V'),
+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.
+#if FF_API_CODEC_ID
+#include "old_codec_ids.h"
+#endif
+};
+/**
+* This struct describes the properties of a single codec described by an
+* AVCodecID.
+* @see avcodec_get_descriptor()
+*/
+typedef struct AVCodecDescriptor {
+enum AVCodecID     id;
+enum AVMediaType type;
+/**
+* Name of the codec described by this descriptor. It is non-empty and
+* unique for each codec descriptor. It should contain alphanumeric
+* characters and '_' only.
+*/
+const char      *name;
+/**
+* A more descriptive name for this codec. May be NULL.
+*/
+const char *long_name;
+/**
+* Codec properties, a combination of AV_CODEC_PROP_* flags.
+*/
+int             props;
+} AVCodecDescriptor;
+/**
+* Codec uses only intra compression.
+* Video codecs only.
+*/
+#define AV_CODEC_PROP_INTRA_ONLY    (1 << 0)
+/**
+* Codec supports lossy compression. Audio and video codecs only.
+* @note a codec may support both lossy and lossless
+* compression modes
+*/
+#define AV_CODEC_PROP_LOSSY         (1 << 1)
+/**
+* Codec supports lossless compression. Audio and video codecs only.
+*/
+#define AV_CODEC_PROP_LOSSLESS      (1 << 2)
+/**
+* Subtitle codec is bitmap based
+* Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
+*/
+#define AV_CODEC_PROP_BITMAP_SUB    (1 << 16)
+/**
+* Subtitle codec is text based.
+* Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
+*/
+#define AV_CODEC_PROP_TEXT_SUB      (1 << 17)
+/**
+* @ingroup lavc_decoding
+* Required number of additionally allocated bytes at the end of the input bitstream for decoding.
+* This is mainly needed because some optimized bitstream readers read
+* 32 or 64 bit at once and could read over the end.<br>
+* Note: If the first 23 bits of the additional bytes are not 0, then damaged
+* MPEG bitstreams could cause overread and segfault.
+*/
+#define FF_INPUT_BUFFER_PADDING_SIZE 16
+/**
+* @ingroup lavc_encoding
+* minimum encoding buffer size
+* Used to avoid some checks during header writing.
+*/
+#define FF_MIN_BUFFER_SIZE 16384
+/**
+* @ingroup lavc_encoding
+* motion estimation type.
+*/
+enum Motion_Est_ID {
+ME_ZERO = 1,    ///< no search, that is use 0,0 vector whenever one is needed
+ME_FULL,
+ME_LOG,
+ME_PHODS,
+ME_EPZS,        ///< enhanced predictive zonal search
+ME_X1,          ///< reserved for experiments
+ME_HEX,         ///< hexagon based search
+ME_UMH,         ///< uneven multi-hexagon search
+ME_TESA,        ///< transformed exhaustive search algorithm
+ME_ITER=50,     ///< iterative search
+};
+/**
+* @ingroup lavc_decoding
+*/
+enum AVDiscard{
+/* We leave some space between them for extensions (drop some
+* keyframes for intra-only or drop just some bidir frames). */
+AVDISCARD_NONE    =-16, ///< discard nothing
+AVDISCARD_DEFAULT =  0, ///< discard useless packets like 0 size packets in avi
+AVDISCARD_NONREF  =  8, ///< discard all non reference
+AVDISCARD_BIDIR   = 16, ///< discard all bidirectional frames
+AVDISCARD_NONKEY  = 32, ///< discard all frames except keyframes
+AVDISCARD_ALL     = 48, ///< discard all
+};
+enum AVColorPrimaries{
+AVCOL_PRI_BT709       = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
+AVCOL_PRI_UNSPECIFIED = 2,
+AVCOL_PRI_BT470M      = 4,
+AVCOL_PRI_BT470BG     = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
+AVCOL_PRI_SMPTE170M   = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
+AVCOL_PRI_SMPTE240M   = 7, ///< functionally identical to above
+AVCOL_PRI_FILM        = 8,
+AVCOL_PRI_NB             , ///< Not part of ABI
+};
+enum AVColorTransferCharacteristic{
+AVCOL_TRC_BT709       = 1, ///< also ITU-R BT1361
+AVCOL_TRC_UNSPECIFIED = 2,
+AVCOL_TRC_GAMMA22     = 4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
+AVCOL_TRC_GAMMA28     = 5, ///< also ITU-R BT470BG
+AVCOL_TRC_SMPTE240M   = 7,
+AVCOL_TRC_NB             , ///< Not part of ABI
+};
+enum AVColorSpace{
+AVCOL_SPC_RGB         = 0,
+AVCOL_SPC_BT709       = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 xvYCC709 / SMPTE RP177 Annex B
+AVCOL_SPC_UNSPECIFIED = 2,
+AVCOL_SPC_FCC         = 4,
+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
+AVCOL_SPC_SMPTE170M   = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC / functionally identical to above
+AVCOL_SPC_SMPTE240M   = 7,
+AVCOL_SPC_YCOCG       = 8, ///< Used by Dirac / VC-2 and H.264 FRext, see ITU-T SG16
+AVCOL_SPC_NB             , ///< Not part of ABI
+};
+#define AVCOL_SPC_YCGCO AVCOL_SPC_YCOCG
+enum AVColorRange{
+AVCOL_RANGE_UNSPECIFIED = 0,
+AVCOL_RANGE_MPEG        = 1, ///< the normal 219*2^(n-8) "MPEG" YUV ranges
+AVCOL_RANGE_JPEG        = 2, ///< the normal     2^n-1   "JPEG" YUV ranges
+AVCOL_RANGE_NB             , ///< Not part of ABI
+};
+/**
+*  X   X      3 4 X      X are luma samples,
+*             1 2        1-6 are possible chroma positions
+*  X   X      5 6 X      0 is undefined/unknown position
+*/
+enum AVChromaLocation{
+AVCHROMA_LOC_UNSPECIFIED = 0,
+AVCHROMA_LOC_LEFT        = 1, ///< mpeg2/4, h264 default
+AVCHROMA_LOC_CENTER      = 2, ///< mpeg1, jpeg, h263
+AVCHROMA_LOC_TOPLEFT     = 3, ///< DV
+AVCHROMA_LOC_TOP         = 4,
+AVCHROMA_LOC_BOTTOMLEFT  = 5,
+AVCHROMA_LOC_BOTTOM      = 6,
+AVCHROMA_LOC_NB             , ///< Not part of ABI
+};
+enum AVAudioServiceType {
+AV_AUDIO_SERVICE_TYPE_MAIN              = 0,
+AV_AUDIO_SERVICE_TYPE_EFFECTS           = 1,
+AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
+AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED  = 3,
+AV_AUDIO_SERVICE_TYPE_DIALOGUE          = 4,
+AV_AUDIO_SERVICE_TYPE_COMMENTARY        = 5,
+AV_AUDIO_SERVICE_TYPE_EMERGENCY         = 6,
+AV_AUDIO_SERVICE_TYPE_VOICE_OVER        = 7,
+AV_AUDIO_SERVICE_TYPE_KARAOKE           = 8,
+AV_AUDIO_SERVICE_TYPE_NB                   , ///< Not part of ABI
+};
+/**
+* @ingroup lavc_encoding
+*/
+typedef struct RcOverride{
+int start_frame;
+int end_frame;
+int qscale; // If this is 0 then quality_factor will be used instead.
+float quality_factor;
+} RcOverride;
+#define FF_MAX_B_FRAMES 16
+/* encoding support
+These flags can be passed in AVCodecContext.flags before initialization.
+Note: Not everything is supported yet.
+*/
+/**
+* Allow decoders to produce frames with data planes that are not aligned
+* to CPU requirements (e.g. due to cropping).
+*/
+#define CODEC_FLAG_UNALIGNED 0x0001
+#define CODEC_FLAG_QSCALE 0x0002  ///< Use fixed qscale.
+#define CODEC_FLAG_4MV    0x0004  ///< 4 MV per MB allowed / advanced prediction for H.263.
+#define CODEC_FLAG_QPEL   0x0010  ///< Use qpel MC.
+#define CODEC_FLAG_GMC    0x0020  ///< Use GMC.
+#define CODEC_FLAG_MV0    0x0040  ///< Always try a MB with MV=<0,0>.
+/**
+* The parent program guarantees that the input for B-frames containing
+* streams is not written to for at least s->max_b_frames+1 frames, if
+* this is not set the input will be copied.
+*/
+#define CODEC_FLAG_INPUT_PRESERVED 0x0100
+#define CODEC_FLAG_PASS1           0x0200   ///< Use internal 2pass ratecontrol in first pass mode.
+#define CODEC_FLAG_PASS2           0x0400   ///< Use internal 2pass ratecontrol in second pass mode.
+#define CODEC_FLAG_GRAY            0x2000   ///< Only decode/encode grayscale.
+#define CODEC_FLAG_EMU_EDGE        0x4000   ///< Don't draw edges.
+#define CODEC_FLAG_PSNR            0x8000   ///< error[?] variables will be set during encoding.
+#define CODEC_FLAG_TRUNCATED       0x00010000 /** Input bitstream might be truncated at a random
+location instead of only at frame boundaries. */
+#define CODEC_FLAG_NORMALIZE_AQP  0x00020000 ///< Normalize adaptive quantization.
+#define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
+#define CODEC_FLAG_LOW_DELAY      0x00080000 ///< Force low delay.
+#define CODEC_FLAG_GLOBAL_HEADER  0x00400000 ///< Place global headers in extradata instead of every keyframe.
+#define CODEC_FLAG_BITEXACT       0x00800000 ///< Use only bitexact stuff (except (I)DCT).
+/* Fx : Flag for h263+ extra options */
+#define CODEC_FLAG_AC_PRED        0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
+#define CODEC_FLAG_LOOP_FILTER    0x00000800 ///< loop filter
+#define CODEC_FLAG_INTERLACED_ME  0x20000000 ///< interlaced motion estimation
+#define CODEC_FLAG_CLOSED_GOP     0x80000000
+#define CODEC_FLAG2_FAST          0x00000001 ///< Allow non spec compliant speedup tricks.
+#define CODEC_FLAG2_NO_OUTPUT     0x00000004 ///< Skip bitstream encoding.
+#define CODEC_FLAG2_LOCAL_HEADER  0x00000008 ///< Place global headers at every keyframe instead of in extradata.
+#define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
+#define CODEC_FLAG2_IGNORE_CROP   0x00010000 ///< Discard cropping information from SPS.
+#define CODEC_FLAG2_CHUNKS        0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
+#define CODEC_FLAG2_SHOW_ALL      0x00400000 ///< Show all frames before the first keyframe
+/* Unsupported options :
+*              Syntax Arithmetic coding (SAC)
+*              Reference Picture Selection
+*              Independent Segment Decoding */
+/* /Fx */
+/* codec capabilities */
+#define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
+/**
+* Codec uses get_buffer() for allocating buffers and supports custom allocators.
+* If not set, it might not use get_buffer() at all or use operations that
+* assume the buffer was allocated by avcodec_default_get_buffer.
+*/
+#define CODEC_CAP_DR1             0x0002
+#define CODEC_CAP_TRUNCATED       0x0008
+/* Codec can export data for HW decoding (XvMC). */
+#define CODEC_CAP_HWACCEL         0x0010
+/**
+* Encoder or decoder requires flushing with NULL input at the end in order to
+* give the complete and correct output.
+*
+* NOTE: If this flag is not set, the codec is guaranteed to never be fed with
+*       with NULL data. The user can still send NULL data to the public encode
+*       or decode function, but libavcodec will not pass it along to the codec
+*       unless this flag is set.
+*
+* Decoders:
+* The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
+* avpkt->size=0 at the end to get the delayed data until the decoder no longer
+* returns frames.
+*
+* Encoders:
+* The encoder needs to be fed with NULL data at the end of encoding until the
+* encoder no longer returns data.
+*
+* NOTE: For encoders implementing the AVCodec.encode2() function, setting this
+*       flag also means that the encoder must set the pts and duration for
+*       each output packet. If this flag is not set, the pts and duration will
+*       be determined by libavcodec from the input frame.
+*/
+#define CODEC_CAP_DELAY           0x0020
+/**
+* Codec can be fed a final frame with a smaller size.
+* This can be used to prevent truncation of the last audio samples.
+*/
+#define CODEC_CAP_SMALL_LAST_FRAME 0x0040
+/**
+* Codec can export data for HW decoding (VDPAU).
+*/
+#define CODEC_CAP_HWACCEL_VDPAU    0x0080
+/**
+* Codec can output multiple frames per AVPacket
+* Normally demuxers return one frame at a time, demuxers which do not do
+* are connected to a parser to split what they return into proper frames.
+* This flag is reserved to the very rare category of codecs which have a
+* bitstream that cannot be split into frames without timeconsuming
+* operations like full decoding. Demuxers carring such bitstreams thus
+* may return multiple frames in a packet. This has many disadvantages like
+* prohibiting stream copy in many cases thus it should only be considered
+* as a last resort.
+*/
+#define CODEC_CAP_SUBFRAMES        0x0100
+/**
+* Codec is experimental and is thus avoided in favor of non experimental
+* encoders
+*/
+#define CODEC_CAP_EXPERIMENTAL     0x0200
+/**
+* Codec should fill in channel configuration and samplerate instead of container
+*/
+#define CODEC_CAP_CHANNEL_CONF     0x0400
+/**
+* Codec is able to deal with negative linesizes
+*/
+#define CODEC_CAP_NEG_LINESIZES    0x0800
+/**
+* Codec supports frame-level multithreading.
+*/
+#define CODEC_CAP_FRAME_THREADS    0x1000
+/**
+* Codec supports slice-based (or partition-based) multithreading.
+*/
+#define CODEC_CAP_SLICE_THREADS    0x2000
+/**
+* Codec supports changed parameters at any point.
+*/
+#define CODEC_CAP_PARAM_CHANGE     0x4000
+/**
+* Codec supports avctx->thread_count == 0 (auto).
+*/
+#define CODEC_CAP_AUTO_THREADS     0x8000
+/**
+* Audio encoder supports receiving a different number of samples in each call.
+*/
+#define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
+/**
+* Codec is intra only.
+*/
+#define CODEC_CAP_INTRA_ONLY       0x40000000
+/**
+* Codec is lossless.
+*/
+#define CODEC_CAP_LOSSLESS         0x80000000
+//The following defines may change, don't expect compatibility if you use them.
+#define MB_TYPE_INTRA4x4   0x0001
+#define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
+#define MB_TYPE_INTRA_PCM  0x0004 //FIXME H.264-specific
+#define MB_TYPE_16x16      0x0008
+#define MB_TYPE_16x8       0x0010
+#define MB_TYPE_8x16       0x0020
+#define MB_TYPE_8x8        0x0040
+#define MB_TYPE_INTERLACED 0x0080
+#define MB_TYPE_DIRECT2    0x0100 //FIXME
+#define MB_TYPE_ACPRED     0x0200
+#define MB_TYPE_GMC        0x0400
+#define MB_TYPE_SKIP       0x0800
+#define MB_TYPE_P0L0       0x1000
+#define MB_TYPE_P1L0       0x2000
+#define MB_TYPE_P0L1       0x4000
+#define MB_TYPE_P1L1       0x8000
+#define MB_TYPE_L0         (MB_TYPE_P0L0 | MB_TYPE_P1L0)
+#define MB_TYPE_L1         (MB_TYPE_P0L1 | MB_TYPE_P1L1)
+#define MB_TYPE_L0L1       (MB_TYPE_L0   | MB_TYPE_L1)
+#define MB_TYPE_QUANT      0x00010000
+#define MB_TYPE_CBP        0x00020000
+//Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
+/**
+* Pan Scan area.
+* This specifies the area which should be displayed.
+* Note there may be multiple such areas for one frame.
+*/
+typedef struct AVPanScan{
+/**
+* id
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+int id;
+/**
+* width and height in 1/16 pel
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+int width;
+int height;
+/**
+* position of the top left corner in 1/16 pel for up to 3 fields/frames
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+int16_t position[3][2];
+}AVPanScan;
+#define FF_QSCALE_TYPE_MPEG1 0
+#define FF_QSCALE_TYPE_MPEG2 1
+#define FF_QSCALE_TYPE_H264  2
+#define FF_QSCALE_TYPE_VP56  3
+#if FF_API_GET_BUFFER
+#define FF_BUFFER_TYPE_INTERNAL 1
+#define FF_BUFFER_TYPE_USER     2 ///< direct rendering buffers (image is (de)allocated by user)
+#define FF_BUFFER_TYPE_SHARED   4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
+#define FF_BUFFER_TYPE_COPY     8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
+#define FF_BUFFER_HINTS_VALID    0x01 // Buffer hints value is meaningful (if 0 ignore).
+#define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
+#define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
+#define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
+#endif
+/**
+* The decoder will keep a reference to the frame and may reuse it later.
+*/
+#define AV_GET_BUFFER_FLAG_REF (1 << 0)
+/**
+* @defgroup lavc_packet AVPacket
+*
+* Types and functions for working with AVPacket.
+* @{
+*/
+enum AVPacketSideDataType {
+AV_PKT_DATA_PALETTE,
+AV_PKT_DATA_NEW_EXTRADATA,
+/**
+* An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
+* @code
+* u32le param_flags
+* if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
+*     s32le channel_count
+* if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
+*     u64le channel_layout
+* if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
+*     s32le sample_rate
+* if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
+*     s32le width
+*     s32le height
+* @endcode
+*/
+AV_PKT_DATA_PARAM_CHANGE,
+/**
+* An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
+* structures with info about macroblocks relevant to splitting the
+* packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
+* That is, it does not necessarily contain info about all macroblocks,
+* as long as the distance between macroblocks in the info is smaller
+* than the target payload size.
+* Each MB info structure is 12 bytes, and is laid out as follows:
+* @code
+* u32le bit offset from the start of the packet
+* u8    current quantizer at the start of the macroblock
+* u8    GOB number
+* u16le macroblock address within the GOB
+* u8    horizontal MV predictor
+* u8    vertical MV predictor
+* u8    horizontal MV predictor for block number 3
+* u8    vertical MV predictor for block number 3
+* @endcode
+*/
+AV_PKT_DATA_H263_MB_INFO,
+/**
+* Recommmends skipping the specified number of samples
+* @code
+* u32le number of samples to skip from start of this packet
+* u32le number of samples to skip from end of this packet
+* u8    reason for start skip
+* u8    reason for end   skip (0=padding silence, 1=convergence)
+* @endcode
+*/
+AV_PKT_DATA_SKIP_SAMPLES=70,
+/**
+* An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
+* the packet may contain "dual mono" audio specific to Japanese DTV
+* and if it is true, recommends only the selected channel to be used.
+* @code
+* u8    selected channels (0=mail/left, 1=sub/right, 2=both)
+* @endcode
+*/
+AV_PKT_DATA_JP_DUALMONO,
+/**
+* A list of zero terminated key/value strings. There is no end marker for
+* the list, so it is required to rely on the side data size to stop.
+*/
+AV_PKT_DATA_STRINGS_METADATA,
+/**
+* Subtitle event position
+* @code
+* u32le x1
+* u32le y1
+* u32le x2
+* u32le y2
+* @endcode
+*/
+AV_PKT_DATA_SUBTITLE_POSITION,
+/**
+* Data found in BlockAdditional element of matroska container. There is
+* no end marker for the data, so it is required to rely on the side data
+* size to recognize the end. 8 byte id (as found in BlockAddId) followed
+* by data.
+*/
+AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
+};
+/**
+* This structure stores compressed data. It is typically exported by demuxers
+* and then passed as input to decoders, or received as output from encoders and
+* then passed to muxers.
+*
+* For video, it should typically contain one compressed frame. For audio it may
+* contain several compressed frames.
+*
+* AVPacket is one of the few structs in FFmpeg, whose size is a part of public
+* ABI. Thus it may be allocated on stack and no new fields can be added to it
+* without libavcodec and libavformat major bump.
+*
+* The semantics of data ownership depends on the buf or destruct (deprecated)
+* fields. If either is set, the packet data is dynamically allocated and is
+* valid indefinitely until av_free_packet() is called (which in turn calls
+* av_buffer_unref()/the destruct callback to free the data). If neither is set,
+* the packet data is typically backed by some static buffer somewhere and is
+* only valid for a limited time (e.g. until the next read call when demuxing).
+*
+* The side data is always allocated with av_malloc() and is freed in
+* av_free_packet().
+*/
+typedef struct AVPacket {
+/**
+* A reference to the reference-counted buffer where the packet data is
+* stored.
+* May be NULL, then the packet data is not reference-counted.
+*/
+AVBufferRef *buf;
+/**
+* Presentation timestamp in AVStream->time_base units; the time at which
+* the decompressed packet will be presented to the user.
+* Can be AV_NOPTS_VALUE if it is not stored in the file.
+* pts MUST be larger or equal to dts as presentation cannot happen before
+* decompression, unless one wants to view hex dumps. Some formats misuse
+* the terms dts and pts/cts to mean something different. Such timestamps
+* must be converted to true pts/dts before they are stored in AVPacket.
+*/
+int64_t pts;
+/**
+* Decompression timestamp in AVStream->time_base units; the time at which
+* the packet is decompressed.
+* Can be AV_NOPTS_VALUE if it is not stored in the file.
+*/
+int64_t dts;
+uint8_t *data;
+int   size;
+int   stream_index;
+/**
+* A combination of AV_PKT_FLAG values
+*/
+int   flags;
+/**
+* Additional packet data that can be provided by the container.
+* Packet can contain several types of side information.
+*/
+struct {
+uint8_t *data;
+int      size;
+enum AVPacketSideDataType type;
+} *side_data;
+int side_data_elems;
+/**
+* Duration of this packet in AVStream->time_base units, 0 if unknown.
+* Equals next_pts - this_pts in presentation order.
+*/
+int   duration;
+#if FF_API_DESTRUCT_PACKET
+attribute_deprecated
+void  (*destruct)(struct AVPacket *);
+attribute_deprecated
+void  *priv;
+#endif
+int64_t pos;                            ///< byte position in stream, -1 if unknown
+/**
+* Time difference in AVStream->time_base units from the pts of this
+* packet to the point at which the output from the decoder has converged
+* independent from the availability of previous frames. That is, the
+* frames are virtually identical no matter if decoding started from
+* the very first frame or from this keyframe.
+* Is AV_NOPTS_VALUE if unknown.
+* This field is not the display duration of the current packet.
+* This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
+* set.
+*
+* The purpose of this field is to allow seeking in streams that have no
+* keyframes in the conventional sense. It corresponds to the
+* recovery point SEI in H.264 and match_time_delta in NUT. It is also
+* essential for some types of subtitle streams to ensure that all
+* subtitles are correctly displayed after seeking.
+*/
+int64_t convergence_duration;
+} AVPacket;
+#define AV_PKT_FLAG_KEY     0x0001 ///< The packet contains a keyframe
+#define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
+enum AVSideDataParamChangeFlags {
+AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT  = 0x0001,
+AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
+AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE    = 0x0004,
+AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS     = 0x0008,
+};
+/**
+* @}
+*/
+struct AVCodecInternal;
+enum AVFieldOrder {
+AV_FIELD_UNKNOWN,
+AV_FIELD_PROGRESSIVE,
+AV_FIELD_TT,          //< Top coded_first, top displayed first
+AV_FIELD_BB,          //< Bottom coded first, bottom displayed first
+AV_FIELD_TB,          //< Top coded first, bottom displayed first
+AV_FIELD_BT,          //< Bottom coded first, top displayed first
+};
+/**
+* main external API structure.
+* New fields can be added to the end with minor version bumps.
+* Removal, reordering and changes to existing fields require a major
+* version bump.
+* Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
+* applications.
+* sizeof(AVCodecContext) must not be used outside libav*.
+*/
+typedef struct AVCodecContext {
+/**
+* information on struct for av_log
+* - set by avcodec_alloc_context3
+*/
+const AVClass *av_class;
+int log_level_offset;
+enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
+const struct AVCodec  *codec;
+char             codec_name[32];
+enum AVCodecID     codec_id; /* see AV_CODEC_ID_xxx */
+/**
+* fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
+* This is used to work around some encoder bugs.
+* A demuxer should set this to what is stored in the field used to identify the codec.
+* If there are multiple such fields in a container then the demuxer should choose the one
+* which maximizes the information about the used codec.
+* If the codec tag field in a container is larger than 32 bits then the demuxer should
+* remap the longer ID to 32 bits with a table or other structure. Alternatively a new
+* extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
+* first.
+* - encoding: Set by user, if not then the default based on codec_id will be used.
+* - decoding: Set by user, will be converted to uppercase by libavcodec during init.
+*/
+unsigned int codec_tag;
+/**
+* fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
+* This is used to work around some encoder bugs.
+* - encoding: unused
+* - decoding: Set by user, will be converted to uppercase by libavcodec during init.
+*/
+unsigned int stream_codec_tag;
+void *priv_data;
+/**
+* Private context used for internal data.
+*
+* Unlike priv_data, this is not codec-specific. It is used in general
+* libavcodec functions.
+*/
+struct AVCodecInternal *internal;
+/**
+* Private data of the user, can be used to carry app specific stuff.
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+void *opaque;
+/**
+* the average bitrate
+* - encoding: Set by user; unused for constant quantizer encoding.
+* - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
+*/
+int bit_rate;
+/**
+* number of bits the bitstream is allowed to diverge from the reference.
+*           the reference can be CBR (for CBR pass1) or VBR (for pass2)
+* - encoding: Set by user; unused for constant quantizer encoding.
+* - decoding: unused
+*/
+int bit_rate_tolerance;
+/**
+* Global quality for codecs which cannot change it per frame.
+* This should be proportional to MPEG-1/2/4 qscale.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int global_quality;
+/**
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int compression_level;
+#define FF_COMPRESSION_DEFAULT -1
+/**
+* CODEC_FLAG_*.
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int flags;
+/**
+* CODEC_FLAG2_*
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int flags2;
+/**
+* some codecs need / can use extradata like Huffman tables.
+* mjpeg: Huffman tables
+* rv10: additional flags
+* mpeg4: global headers (they can be in the bitstream or here)
+* The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
+* than extradata_size to avoid prolems if it is read with the bitstream reader.
+* The bytewise contents of extradata must not depend on the architecture or CPU endianness.
+* - encoding: Set/allocated/freed by libavcodec.
+* - decoding: Set/allocated/freed by user.
+*/
+uint8_t *extradata;
+int extradata_size;
+/**
+* This is the fundamental unit of time (in seconds) in terms
+* of which frame timestamps are represented. For fixed-fps content,
+* timebase should be 1/framerate and timestamp increments should be
+* identically 1.
+* - encoding: MUST be set by user.
+* - decoding: Set by libavcodec.
+*/
+AVRational time_base;
+/**
+* For some codecs, the time base is closer to the field rate than the frame rate.
+* Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
+* if no telecine is used ...
+*
+* Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
+*/
+int ticks_per_frame;
+/**
+* Codec delay.
+*
+* Encoding: Number of frames delay there will be from the encoder input to
+*           the decoder output. (we assume the decoder matches the spec)
+* Decoding: Number of frames delay in addition to what a standard decoder
+*           as specified in the spec would produce.
+*
+* Video:
+*   Number of frames the decoded output will be delayed relative to the
+*   encoded input.
+*
+* Audio:
+*   For encoding, this is the number of "priming" samples added to the
+*   beginning of the stream. The decoded output will be delayed by this
+*   many samples relative to the input to the encoder. Note that this
+*   field is purely informational and does not directly affect the pts
+*   output by the encoder, which should always be based on the actual
+*   presentation time, including any delay.
+*   For decoding, this is the number of samples the decoder needs to
+*   output before the decoder's output is valid. When seeking, you should
+*   start decoding this many samples prior to your desired seek point.
+*
+* - encoding: Set by libavcodec.
+* - decoding: Set by libavcodec.
+*/
+int delay;
+/* video only */
+/**
+* picture width / height.
+* - encoding: MUST be set by user.
+* - decoding: May be set by the user before opening the decoder if known e.g.
+*             from the container. Some decoders will require the dimensions
+*             to be set by the caller. During decoding, the decoder may
+*             overwrite those values as required.
+*/
+int width, height;
+/**
+* Bitstream width / height, may be different from width/height e.g. when
+* the decoded frame is cropped before being output or lowres is enabled.
+* - encoding: unused
+* - decoding: May be set by the user before opening the decoder if known
+*             e.g. from the container. During decoding, the decoder may
+*             overwrite those values as required.
+*/
+int coded_width, coded_height;
+#define FF_ASPECT_EXTENDED 15
+/**
+* the number of pictures in a group of pictures, or 0 for intra_only
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int gop_size;
+/**
+* Pixel format, see AV_PIX_FMT_xxx.
+* May be set by the demuxer if known from headers.
+* May be overridden by the decoder if it knows better.
+* - encoding: Set by user.
+* - decoding: Set by user if known, overridden by libavcodec if known
+*/
+enum AVPixelFormat pix_fmt;
+/**
+* Motion estimation algorithm used for video coding.
+* 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
+* 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
+* - encoding: MUST be set by user.
+* - decoding: unused
+*/
+int me_method;
+/**
+* If non NULL, 'draw_horiz_band' is called by the libavcodec
+* decoder to draw a horizontal band. It improves cache usage. Not
+* all codecs can do that. You must check the codec capabilities
+* beforehand.
+* When multithreading is used, it may be called from multiple threads
+* at the same time; threads might draw different parts of the same AVFrame,
+* or multiple AVFrames, and there is no guarantee that slices will be drawn
+* in order.
+* The function is also used by hardware acceleration APIs.
+* It is called at least once during frame decoding to pass
+* the data needed for hardware render.
+* In that mode instead of pixel data, AVFrame points to
+* a structure specific to the acceleration API. The application
+* reads the structure and can change some fields to indicate progress
+* or mark state.
+* - encoding: unused
+* - decoding: Set by user.
+* @param height the height of the slice
+* @param y the y position of the slice
+* @param type 1->top field, 2->bottom field, 3->frame
+* @param offset offset into the AVFrame.data from which the slice should be read
+*/
+void (*draw_horiz_band)(struct AVCodecContext *s,
+const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
+int y, int type, int height);
+/**
+* callback to negotiate the pixelFormat
+* @param fmt is the list of formats which are supported by the codec,
+* it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
+* The first is always the native one.
+* @return the chosen format
+* - encoding: unused
+* - decoding: Set by user, if not set the native format will be chosen.
+*/
+enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
+/**
+* maximum number of B-frames between non-B-frames
+* Note: The output will be delayed by max_b_frames+1 relative to the input.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int max_b_frames;
+/**
+* qscale factor between IP and B-frames
+* If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
+* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float b_quant_factor;
+/** obsolete FIXME remove */
+int rc_strategy;
+#define FF_RC_STRATEGY_XVID 1
+int b_frame_strategy;
+/**
+* qscale offset between IP and B-frames
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float b_quant_offset;
+/**
+* Size of the frame reordering buffer in the decoder.
+* For MPEG-2 it is 1 IPB or 0 low delay IP.
+* - encoding: Set by libavcodec.
+* - decoding: Set by libavcodec.
+*/
+int has_b_frames;
+/**
+* 0-> h263 quant 1-> mpeg quant
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mpeg_quant;
+/**
+* qscale factor between P and I-frames
+* If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
+* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float i_quant_factor;
+/**
+* qscale offset between P and I-frames
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float i_quant_offset;
+/**
+* luminance masking (0-> disabled)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float lumi_masking;
+/**
+* temporary complexity masking (0-> disabled)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float temporal_cplx_masking;
+/**
+* spatial complexity masking (0-> disabled)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float spatial_cplx_masking;
+/**
+* p block masking (0-> disabled)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float p_masking;
+/**
+* darkness masking (0-> disabled)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float dark_masking;
+/**
+* slice count
+* - encoding: Set by libavcodec.
+* - decoding: Set by user (or 0).
+*/
+int slice_count;
+/**
+* prediction method (needed for huffyuv)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int prediction_method;
+#define FF_PRED_LEFT   0
+#define FF_PRED_PLANE  1
+#define FF_PRED_MEDIAN 2
+/**
+* slice offsets in the frame in bytes
+* - encoding: Set/allocated by libavcodec.
+* - decoding: Set/allocated by user (or NULL).
+*/
+int *slice_offset;
+/**
+* sample aspect ratio (0 if unknown)
+* That is the width of a pixel divided by the height of the pixel.
+* Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+AVRational sample_aspect_ratio;
+/**
+* motion estimation comparison function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_cmp;
+/**
+* subpixel motion estimation comparison function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_sub_cmp;
+/**
+* macroblock comparison function (not supported yet)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mb_cmp;
+/**
+* interlaced DCT comparison function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int ildct_cmp;
+#define FF_CMP_SAD    0
+#define FF_CMP_SSE    1
+#define FF_CMP_SATD   2
+#define FF_CMP_DCT    3
+#define FF_CMP_PSNR   4
+#define FF_CMP_BIT    5
+#define FF_CMP_RD     6
+#define FF_CMP_ZERO   7
+#define FF_CMP_VSAD   8
+#define FF_CMP_VSSE   9
+#define FF_CMP_NSSE   10
+#define FF_CMP_W53    11
+#define FF_CMP_W97    12
+#define FF_CMP_DCTMAX 13
+#define FF_CMP_DCT264 14
+#define FF_CMP_CHROMA 256
+/**
+* ME diamond size & shape
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int dia_size;
+/**
+* amount of previous MV predictors (2a+1 x 2a+1 square)
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int last_predictor_count;
+/**
+* prepass for motion estimation
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int pre_me;
+/**
+* motion estimation prepass comparison function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_pre_cmp;
+/**
+* ME prepass diamond size & shape
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int pre_dia_size;
+/**
+* subpel ME quality
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_subpel_quality;
+/**
+* DTG active format information (additional aspect ratio
+* information only used in DVB MPEG-2 transport streams)
+* 0 if not set.
+*
+* - encoding: unused
+* - decoding: Set by decoder.
+*/
+int dtg_active_format;
+#define FF_DTG_AFD_SAME         8
+#define FF_DTG_AFD_4_3          9
+#define FF_DTG_AFD_16_9         10
+#define FF_DTG_AFD_14_9         11
+#define FF_DTG_AFD_4_3_SP_14_9  13
+#define FF_DTG_AFD_16_9_SP_14_9 14
+#define FF_DTG_AFD_SP_4_3       15
+/**
+* maximum motion estimation search range in subpel units
+* If 0 then no limit.
+*
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_range;
+/**
+* intra quantizer bias
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int intra_quant_bias;
+#define FF_DEFAULT_QUANT_BIAS 999999
+/**
+* inter quantizer bias
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int inter_quant_bias;
+/**
+* slice flags
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int slice_flags;
+#define SLICE_FLAG_CODED_ORDER    0x0001 ///< draw_horiz_band() is called in coded order instead of display
+#define SLICE_FLAG_ALLOW_FIELD    0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
+#define SLICE_FLAG_ALLOW_PLANE    0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
+/**
+* XVideo Motion Acceleration
+* - encoding: forbidden
+* - decoding: set by decoder
+*/
+int xvmc_acceleration;
+/**
+* macroblock decision mode
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mb_decision;
+#define FF_MB_DECISION_SIMPLE 0        ///< uses mb_cmp
+#define FF_MB_DECISION_BITS   1        ///< chooses the one which needs the fewest bits
+#define FF_MB_DECISION_RD     2        ///< rate distortion
+/**
+* custom intra quantization matrix
+* - encoding: Set by user, can be NULL.
+* - decoding: Set by libavcodec.
+*/
+uint16_t *intra_matrix;
+/**
+* custom inter quantization matrix
+* - encoding: Set by user, can be NULL.
+* - decoding: Set by libavcodec.
+*/
+uint16_t *inter_matrix;
+/**
+* scene change detection threshold
+* 0 is default, larger means fewer detected scene changes.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int scenechange_threshold;
+/**
+* noise reduction strength
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int noise_reduction;
+/**
+* Motion estimation threshold below which no motion estimation is
+* performed, but instead the user specified motion vectors are used.
+*
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_threshold;
+/**
+* Macroblock threshold below which the user specified macroblock types will be used.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mb_threshold;
+/**
+* precision of the intra DC coefficient - 8
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int intra_dc_precision;
+/**
+* Number of macroblock rows at the top which are skipped.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int skip_top;
+/**
+* Number of macroblock rows at the bottom which are skipped.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int skip_bottom;
+/**
+* Border processing masking, raises the quantizer for mbs on the borders
+* of the picture.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float border_masking;
+/**
+* minimum MB lagrange multipler
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mb_lmin;
+/**
+* maximum MB lagrange multipler
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mb_lmax;
+/**
+*
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int me_penalty_compensation;
+/**
+*
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int bidir_refine;
+/**
+*
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int brd_scale;
+/**
+* minimum GOP size
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int keyint_min;
+/**
+* number of reference frames
+* - encoding: Set by user.
+* - decoding: Set by lavc.
+*/
+int refs;
+/**
+* chroma qp offset from luma
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int chromaoffset;
+/**
+* Multiplied by qscale for each frame and added to scene_change_score.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int scenechange_factor;
+/**
+*
+* Note: Value depends upon the compare function used for fullpel ME.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int mv0_threshold;
+/**
+* Adjust sensitivity of b_frame_strategy 1.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int b_sensitivity;
+/**
+* Chromaticity coordinates of the source primaries.
+* - encoding: Set by user
+* - decoding: Set by libavcodec
+*/
+enum AVColorPrimaries color_primaries;
+/**
+* Color Transfer Characteristic.
+* - encoding: Set by user
+* - decoding: Set by libavcodec
+*/
+enum AVColorTransferCharacteristic color_trc;
+/**
+* YUV colorspace type.
+* - encoding: Set by user
+* - decoding: Set by libavcodec
+*/
+enum AVColorSpace colorspace;
+/**
+* MPEG vs JPEG YUV range.
+* - encoding: Set by user
+* - decoding: Set by libavcodec
+*/
+enum AVColorRange color_range;
+/**
+* This defines the location of chroma samples.
+* - encoding: Set by user
+* - decoding: Set by libavcodec
+*/
+enum AVChromaLocation chroma_sample_location;
+/**
+* Number of slices.
+* Indicates number of picture subdivisions. Used for parallelized
+* decoding.
+* - encoding: Set by user
+* - decoding: unused
+*/
+int slices;
+/** Field order
+* - encoding: set by libavcodec
+* - decoding: Set by user.
+*/
+enum AVFieldOrder field_order;
+/* audio only */
+int sample_rate; ///< samples per second
+int channels;    ///< number of audio channels
+/**
+* audio sample format
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+enum AVSampleFormat sample_fmt;  ///< sample format
+/* The following data should not be initialized. */
+/**
+* Number of samples per channel in an audio frame.
+*
+* - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
+*   except the last must contain exactly frame_size samples per channel.
+*   May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
+*   frame size is not restricted.
+* - decoding: may be set by some decoders to indicate constant frame size
+*/
+int frame_size;
+/**
+* Frame counter, set by libavcodec.
+*
+* - decoding: total number of frames returned from the decoder so far.
+* - encoding: total number of frames passed to the encoder so far.
+*
+*   @note the counter is not incremented if encoding/decoding resulted in
+*   an error.
+*/
+int frame_number;
+/**
+* number of bytes per packet if constant and known or 0
+* Used by some WAV based audio codecs.
+*/
+int block_align;
+/**
+* Audio cutoff bandwidth (0 means "automatic")
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int cutoff;
+#if FF_API_REQUEST_CHANNELS
+/**
+* Decoder should decode to this many channels if it can (0 for default)
+* - encoding: unused
+* - decoding: Set by user.
+* @deprecated Deprecated in favor of request_channel_layout.
+*/
+int request_channels;
+#endif
+/**
+* Audio channel layout.
+* - encoding: set by user.
+* - decoding: set by user, may be overwritten by libavcodec.
+*/
+uint64_t channel_layout;
+/**
+* Request decoder to use this channel layout if it can (0 for default)
+* - encoding: unused
+* - decoding: Set by user.
+*/
+uint64_t request_channel_layout;
+/**
+* Type of service that the audio stream conveys.
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+enum AVAudioServiceType audio_service_type;
+/**
+* desired sample format
+* - encoding: Not used.
+* - decoding: Set by user.
+* Decoder will decode to this format if it can.
+*/
+enum AVSampleFormat request_sample_fmt;
+#if FF_API_GET_BUFFER
+/**
+* Called at the beginning of each frame to get a buffer for it.
+*
+* The function will set AVFrame.data[], AVFrame.linesize[].
+* AVFrame.extended_data[] must also be set, but it should be the same as
+* AVFrame.data[] except for planar audio with more channels than can fit
+* in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
+* many data pointers as it can hold.
+*
+* if CODEC_CAP_DR1 is not set then get_buffer() must call
+* avcodec_default_get_buffer() instead of providing buffers allocated by
+* some other means.
+*
+* AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
+* need it. avcodec_default_get_buffer() aligns the output buffer properly,
+* but if get_buffer() is overridden then alignment considerations should
+* be taken into account.
+*
+* @see avcodec_default_get_buffer()
+*
+* Video:
+*
+* If pic.reference is set then the frame will be read later by libavcodec.
+* avcodec_align_dimensions2() should be used to find the required width and
+* height, as they normally need to be rounded up to the next multiple of 16.
+*
+* If frame multithreading is used and thread_safe_callbacks is set,
+* it may be called from a different thread, but not from more than one at
+* once. Does not need to be reentrant.
+*
+* @see release_buffer(), reget_buffer()
+* @see avcodec_align_dimensions2()
+*
+* Audio:
+*
+* Decoders request a buffer of a particular size by setting
+* AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
+* however, utilize only part of the buffer by setting AVFrame.nb_samples
+* to a smaller value in the output frame.
+*
+* Decoders cannot use the buffer after returning from
+* avcodec_decode_audio4(), so they will not call release_buffer(), as it
+* is assumed to be released immediately upon return. In some rare cases,
+* a decoder may need to call get_buffer() more than once in a single
+* call to avcodec_decode_audio4(). In that case, when get_buffer() is
+* called again after it has already been called once, the previously
+* acquired buffer is assumed to be released at that time and may not be
+* reused by the decoder.
+*
+* As a convenience, av_samples_get_buffer_size() and
+* av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
+* functions to find the required data size and to fill data pointers and
+* linesize. In AVFrame.linesize, only linesize[0] may be set for audio
+* since all planes must be the same size.
+*
+* @see av_samples_get_buffer_size(), av_samples_fill_arrays()
+*
+* - encoding: unused
+* - decoding: Set by libavcodec, user can override.
+*
+* @deprecated use get_buffer2()
+*/
+attribute_deprecated
+int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
+/**
+* Called to release buffers which were allocated with get_buffer.
+* A released buffer can be reused in get_buffer().
+* pic.data[*] must be set to NULL.
+* May be called from a different thread if frame multithreading is used,
+* but not by more than one thread at once, so does not need to be reentrant.
+* - encoding: unused
+* - decoding: Set by libavcodec, user can override.
+*
+* @deprecated custom freeing callbacks should be set from get_buffer2()
+*/
+attribute_deprecated
+void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
+/**
+* Called at the beginning of a frame to get cr buffer for it.
+* Buffer type (size, hints) must be the same. libavcodec won't check it.
+* libavcodec will pass previous buffer in pic, function should return
+* same buffer or new buffer with old frame "painted" into it.
+* If pic.data[0] == NULL must behave like get_buffer().
+* if CODEC_CAP_DR1 is not set then reget_buffer() must call
+* avcodec_default_reget_buffer() instead of providing buffers allocated by
+* some other means.
+* - encoding: unused
+* - decoding: Set by libavcodec, user can override.
+*/
+attribute_deprecated
+int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
+#endif
+/**
+* This callback is called at the beginning of each frame to get data
+* buffer(s) for it. There may be one contiguous buffer for all the data or
+* there may be a buffer per each data plane or anything in between. What
+* this means is, you may set however many entries in buf[] you feel necessary.
+* Each buffer must be reference-counted using the AVBuffer API (see description
+* of buf[] below).
+*
+* The following fields will be set in the frame before this callback is
+* called:
+* - format
+* - width, height (video only)
+* - sample_rate, channel_layout, nb_samples (audio only)
+* Their values may differ from the corresponding values in
+* AVCodecContext. This callback must use the frame values, not the codec
+* context values, to calculate the required buffer size.
+*
+* This callback must fill the following fields in the frame:
+* - data[]
+* - linesize[]
+* - extended_data:
+*   * if the data is planar audio with more than 8 channels, then this
+*     callback must allocate and fill extended_data to contain all pointers
+*     to all data planes. data[] must hold as many pointers as it can.
+*     extended_data must be allocated with av_malloc() and will be freed in
+*     av_frame_unref().
+*   * otherwise exended_data must point to data
+* - buf[] must contain one or more pointers to AVBufferRef structures. Each of
+*   the frame's data and extended_data pointers must be contained in these. That
+*   is, one AVBufferRef for each allocated chunk of memory, not necessarily one
+*   AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
+*   and av_buffer_ref().
+* - extended_buf and nb_extended_buf must be allocated with av_malloc() by
+*   this callback and filled with the extra buffers if there are more
+*   buffers than buf[] can hold. extended_buf will be freed in
+*   av_frame_unref().
+*
+* If CODEC_CAP_DR1 is not set then get_buffer2() must call
+* avcodec_default_get_buffer2() instead of providing buffers allocated by
+* some other means.
+*
+* Each data plane must be aligned to the maximum required by the target
+* CPU.
+*
+* @see avcodec_default_get_buffer2()
+*
+* Video:
+*
+* If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
+* (read and/or written to if it is writable) later by libavcodec.
+*
+* If CODEC_FLAG_EMU_EDGE is not set in s->flags, the buffer must contain an
+* edge of the size returned by avcodec_get_edge_width() on all sides.
+*
+* avcodec_align_dimensions2() should be used to find the required width and
+* height, as they normally need to be rounded up to the next multiple of 16.
+*
+* If frame multithreading is used and thread_safe_callbacks is set,
+* this callback may be called from a different thread, but not from more
+* than one at once. Does not need to be reentrant.
+*
+* @see avcodec_align_dimensions2()
+*
+* Audio:
+*
+* Decoders request a buffer of a particular size by setting
+* AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
+* however, utilize only part of the buffer by setting AVFrame.nb_samples
+* to a smaller value in the output frame.
+*
+* As a convenience, av_samples_get_buffer_size() and
+* av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
+* functions to find the required data size and to fill data pointers and
+* linesize. In AVFrame.linesize, only linesize[0] may be set for audio
+* since all planes must be the same size.
+*
+* @see av_samples_get_buffer_size(), av_samples_fill_arrays()
+*
+* - encoding: unused
+* - decoding: Set by libavcodec, user can override.
+*/
+int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
+/**
+* If non-zero, the decoded audio and video frames returned from
+* avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
+* and are valid indefinitely. The caller must free them with
+* av_frame_unref() when they are not needed anymore.
+* Otherwise, the decoded frames must not be freed by the caller and are
+* only valid until the next decode call.
+*
+* - encoding: unused
+* - decoding: set by the caller before avcodec_open2().
+*/
+int refcounted_frames;
+/* - encoding parameters */
+float qcompress;  ///< amount of qscale change between easy & hard scenes (0.0-1.0)
+float qblur;      ///< amount of qscale smoothing over time (0.0-1.0)
+/**
+* minimum quantizer
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int qmin;
+/**
+* maximum quantizer
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int qmax;
+/**
+* maximum quantizer difference between frames
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int max_qdiff;
+/**
+* ratecontrol qmin qmax limiting method
+* 0-> clipping, 1-> use a nice continuous function to limit qscale wthin qmin/qmax.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float rc_qsquish;
+float rc_qmod_amp;
+int rc_qmod_freq;
+/**
+* decoder bitstream buffer size
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int rc_buffer_size;
+/**
+* ratecontrol override, see RcOverride
+* - encoding: Allocated/set/freed by user.
+* - decoding: unused
+*/
+int rc_override_count;
+RcOverride *rc_override;
+/**
+* rate control equation
+* - encoding: Set by user
+* - decoding: unused
+*/
+const char *rc_eq;
+/**
+* maximum bitrate
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int rc_max_rate;
+/**
+* minimum bitrate
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int rc_min_rate;
+float rc_buffer_aggressivity;
+/**
+* initial complexity for pass1 ratecontrol
+* - encoding: Set by user.
+* - decoding: unused
+*/
+float rc_initial_cplx;
+/**
+* Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
+* - encoding: Set by user.
+* - decoding: unused.
+*/
+float rc_max_available_vbv_use;
+/**
+* Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
+* - encoding: Set by user.
+* - decoding: unused.
+*/
+float rc_min_vbv_overflow_use;
+/**
+* Number of bits which should be loaded into the rc buffer before decoding starts.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int rc_initial_buffer_occupancy;
+#define FF_CODER_TYPE_VLC       0
+#define FF_CODER_TYPE_AC        1
+#define FF_CODER_TYPE_RAW       2
+#define FF_CODER_TYPE_RLE       3
+#define FF_CODER_TYPE_DEFLATE   4
+/**
+* coder type
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int coder_type;
+/**
+* context model
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int context_model;
+/**
+* minimum Lagrange multipler
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int lmin;
+/**
+* maximum Lagrange multipler
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int lmax;
+/**
+* frame skip threshold
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int frame_skip_threshold;
+/**
+* frame skip factor
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int frame_skip_factor;
+/**
+* frame skip exponent
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int frame_skip_exp;
+/**
+* frame skip comparison function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int frame_skip_cmp;
+/**
+* trellis RD quantization
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int trellis;
+/**
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int min_prediction_order;
+/**
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int max_prediction_order;
+/**
+* GOP timecode frame start number
+* - encoding: Set by user, in non drop frame format
+* - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
+*/
+int64_t timecode_frame_start;
+/* The RTP callback: This function is called    */
+/* every time the encoder has a packet to send. */
+/* It depends on the encoder if the data starts */
+/* with a Start Code (it should). H.263 does.   */
+/* mb_nb contains the number of macroblocks     */
+/* encoded in the RTP payload.                  */
+void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
+int rtp_payload_size;   /* The size of the RTP payload: the coder will  */
+/* do its best to deliver a chunk with size     */
+/* below rtp_payload_size, the chunk will start */
+/* with a start code on some codecs like H.263. */
+/* This doesn't take account of any particular  */
+/* headers inside the transmitted RTP payload.  */
+/* statistics, used for 2-pass encoding */
+int mv_bits;
+int header_bits;
+int i_tex_bits;
+int p_tex_bits;
+int i_count;
+int p_count;
+int skip_count;
+int misc_bits;
+/**
+* number of bits used for the previously encoded frame
+* - encoding: Set by libavcodec.
+* - decoding: unused
+*/
+int frame_bits;
+/**
+* pass1 encoding statistics output buffer
+* - encoding: Set by libavcodec.
+* - decoding: unused
+*/
+char *stats_out;
+/**
+* pass2 encoding statistics input buffer
+* Concatenated stuff from stats_out of pass1 should be placed here.
+* - encoding: Allocated/set/freed by user.
+* - decoding: unused
+*/
+char *stats_in;
+/**
+* Work around bugs in encoders which sometimes cannot be detected automatically.
+* - encoding: Set by user
+* - decoding: Set by user
+*/
+int workaround_bugs;
+#define FF_BUG_AUTODETECT       1  ///< autodetection
+#define FF_BUG_OLD_MSMPEG4      2
+#define FF_BUG_XVID_ILACE       4
+#define FF_BUG_UMP4             8
+#define FF_BUG_NO_PADDING       16
+#define FF_BUG_AMV              32
+#define FF_BUG_AC_VLC           0  ///< Will be removed, libavcodec can now handle these non-compliant files by default.
+#define FF_BUG_QPEL_CHROMA      64
+#define FF_BUG_STD_QPEL         128
+#define FF_BUG_QPEL_CHROMA2     256
+#define FF_BUG_DIRECT_BLOCKSIZE 512
+#define FF_BUG_EDGE             1024
+#define FF_BUG_HPEL_CHROMA      2048
+#define FF_BUG_DC_CLIP          4096
+#define FF_BUG_MS               8192 ///< Work around various bugs in Microsoft's broken decoders.
+#define FF_BUG_TRUNCATED       16384
+/**
+* strictly follow the standard (MPEG4, ...).
+* - encoding: Set by user.
+* - decoding: Set by user.
+* Setting this to STRICT or higher means the encoder and decoder will
+* generally do stupid things, whereas setting it to unofficial or lower
+* will mean the encoder might produce output that is not supported by all
+* spec-compliant decoders. Decoders don't differentiate between normal,
+* unofficial and experimental (that is, they always try to decode things
+* when they can) unless they are explicitly asked to behave stupidly
+* (=strictly conform to the specs)
+*/
+int strict_std_compliance;
+#define FF_COMPLIANCE_VERY_STRICT   2 ///< Strictly conform to an older more strict version of the spec or reference software.
+#define FF_COMPLIANCE_STRICT        1 ///< Strictly conform to all the things in the spec no matter what consequences.
+#define FF_COMPLIANCE_NORMAL        0
+#define FF_COMPLIANCE_UNOFFICIAL   -1 ///< Allow unofficial extensions
+#define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
+/**
+* error concealment flags
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int error_concealment;
+#define FF_EC_GUESS_MVS   1
+#define FF_EC_DEBLOCK     2
+/**
+* debug
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int debug;
+#define FF_DEBUG_PICT_INFO   1
+#define FF_DEBUG_RC          2
+#define FF_DEBUG_BITSTREAM   4
+#define FF_DEBUG_MB_TYPE     8
+#define FF_DEBUG_QP          16
+#define FF_DEBUG_MV          32
+#define FF_DEBUG_DCT_COEFF   0x00000040
+#define FF_DEBUG_SKIP        0x00000080
+#define FF_DEBUG_STARTCODE   0x00000100
+#define FF_DEBUG_PTS         0x00000200
+#define FF_DEBUG_ER          0x00000400
+#define FF_DEBUG_MMCO        0x00000800
+#define FF_DEBUG_BUGS        0x00001000
+#define FF_DEBUG_VIS_QP      0x00002000
+#define FF_DEBUG_VIS_MB_TYPE 0x00004000
+#define FF_DEBUG_BUFFERS     0x00008000
+#define FF_DEBUG_THREADS     0x00010000
+/**
+* debug
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int debug_mv;
+#define FF_DEBUG_VIS_MV_P_FOR  0x00000001 //visualize forward predicted MVs of P frames
+#define FF_DEBUG_VIS_MV_B_FOR  0x00000002 //visualize forward predicted MVs of B frames
+#define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
+/**
+* Error recognition; may misdetect some more or less valid parts as errors.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int err_recognition;
+#define AV_EF_CRCCHECK  (1<<0)
+#define AV_EF_BITSTREAM (1<<1)
+#define AV_EF_BUFFER    (1<<2)
+#define AV_EF_EXPLODE   (1<<3)
+#define AV_EF_CAREFUL    (1<<16)
+#define AV_EF_COMPLIANT  (1<<17)
+#define AV_EF_AGGRESSIVE (1<<18)
+/**
+* opaque 64bit number (generally a PTS) that will be reordered and
+* output in AVFrame.reordered_opaque
+* @deprecated in favor of pkt_pts
+* - encoding: unused
+* - decoding: Set by user.
+*/
+int64_t reordered_opaque;
+/**
+* Hardware accelerator in use
+* - encoding: unused.
+* - decoding: Set by libavcodec
+*/
+struct AVHWAccel *hwaccel;
+/**
+* Hardware accelerator context.
+* For some hardware accelerators, a global context needs to be
+* provided by the user. In that case, this holds display-dependent
+* data FFmpeg cannot instantiate itself. Please refer to the
+* FFmpeg HW accelerator documentation to know how to fill this
+* is. e.g. for VA API, this is a struct vaapi_context.
+* - encoding: unused
+* - decoding: Set by user
+*/
+void *hwaccel_context;
+/**
+* error
+* - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
+* - decoding: unused
+*/
+uint64_t error[AV_NUM_DATA_POINTERS];
+/**
+* DCT algorithm, see FF_DCT_* below
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int dct_algo;
+#define FF_DCT_AUTO    0
+#define FF_DCT_FASTINT 1
+#define FF_DCT_INT     2
+#define FF_DCT_MMX     3
+#define FF_DCT_ALTIVEC 5
+#define FF_DCT_FAAN    6
+/**
+* IDCT algorithm, see FF_IDCT_* below.
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int idct_algo;
+#define FF_IDCT_AUTO          0
+#define FF_IDCT_INT           1
+#define FF_IDCT_SIMPLE        2
+#define FF_IDCT_SIMPLEMMX     3
+#define FF_IDCT_ARM           7
+#define FF_IDCT_ALTIVEC       8
+#define FF_IDCT_SH4           9
+#define FF_IDCT_SIMPLEARM     10
+#define FF_IDCT_IPP           13
+#define FF_IDCT_XVIDMMX       14
+#define FF_IDCT_SIMPLEARMV5TE 16
+#define FF_IDCT_SIMPLEARMV6   17
+#define FF_IDCT_SIMPLEVIS     18
+#define FF_IDCT_FAAN          20
+#define FF_IDCT_SIMPLENEON    22
+#define FF_IDCT_SIMPLEALPHA   23
+/**
+* bits per sample/pixel from the demuxer (needed for huffyuv).
+* - encoding: Set by libavcodec.
+* - decoding: Set by user.
+*/
+int bits_per_coded_sample;
+/**
+* Bits per sample/pixel of internal libavcodec pixel/sample format.
+* - encoding: set by user.
+* - decoding: set by libavcodec.
+*/
+int bits_per_raw_sample;
+#if FF_API_LOWRES
+/**
+* low resolution decoding, 1-> 1/2 size, 2->1/4 size
+* - encoding: unused
+* - decoding: Set by user.
+* Code outside libavcodec should access this field using:
+* av_codec_{get,set}_lowres(avctx)
+*/
+int lowres;
+#endif
+/**
+* the picture in the bitstream
+* - encoding: Set by libavcodec.
+* - decoding: Set by libavcodec.
+*/
+AVFrame *coded_frame;
+/**
+* thread count
+* is used to decide how many independent tasks should be passed to execute()
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int thread_count;
+/**
+* Which multithreading methods to use.
+* Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
+* so clients which cannot provide future frames should not use it.
+*
+* - encoding: Set by user, otherwise the default is used.
+* - decoding: Set by user, otherwise the default is used.
+*/
+int thread_type;
+#define FF_THREAD_FRAME   1 ///< Decode more than one frame at once
+#define FF_THREAD_SLICE   2 ///< Decode more than one part of a single frame at once
+/**
+* Which multithreading methods are in use by the codec.
+* - encoding: Set by libavcodec.
+* - decoding: Set by libavcodec.
+*/
+int active_thread_type;
+/**
+* Set by the client if its custom get_buffer() callback can be called
+* synchronously from another thread, which allows faster multithreaded decoding.
+* draw_horiz_band() will be called from other threads regardless of this setting.
+* Ignored if the default get_buffer() is used.
+* - encoding: Set by user.
+* - decoding: Set by user.
+*/
+int thread_safe_callbacks;
+/**
+* The codec may call this to execute several independent things.
+* It will return only after finishing all tasks.
+* The user may replace this with some multithreaded implementation,
+* the default implementation will execute the parts serially.
+* @param count the number of things to execute
+* - encoding: Set by libavcodec, user can override.
+* - decoding: Set by libavcodec, user can override.
+*/
+int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
+/**
+* The codec may call this to execute several independent things.
+* It will return only after finishing all tasks.
+* The user may replace this with some multithreaded implementation,
+* the default implementation will execute the parts serially.
+* Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
+* @param c context passed also to func
+* @param count the number of things to execute
+* @param arg2 argument passed unchanged to func
+* @param ret return values of executed functions, must have space for "count" values. May be NULL.
+* @param func function that will be called count times, with jobnr from 0 to count-1.
+*             threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
+*             two instances of func executing at the same time will have the same threadnr.
+* @return always 0 currently, but code should handle a future improvement where when any call to func
+*         returns < 0 no further calls to func may be done and < 0 is returned.
+* - encoding: Set by libavcodec, user can override.
+* - decoding: Set by libavcodec, user can override.
+*/
+int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
+/**
+* thread opaque
+* Can be used by execute() to store some per AVCodecContext stuff.
+* - encoding: set by execute()
+* - decoding: set by execute()
+*/
+void *thread_opaque;
+/**
+* noise vs. sse weight for the nsse comparsion function
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int nsse_weight;
+/**
+* profile
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+int profile;
+#define FF_PROFILE_UNKNOWN -99
+#define FF_PROFILE_RESERVED -100
+#define FF_PROFILE_AAC_MAIN 0
+#define FF_PROFILE_AAC_LOW  1
+#define FF_PROFILE_AAC_SSR  2
+#define FF_PROFILE_AAC_LTP  3
+#define FF_PROFILE_AAC_HE   4
+#define FF_PROFILE_AAC_HE_V2 28
+#define FF_PROFILE_AAC_LD   22
+#define FF_PROFILE_AAC_ELD  38
+#define FF_PROFILE_DTS         20
+#define FF_PROFILE_DTS_ES      30
+#define FF_PROFILE_DTS_96_24   40
+#define FF_PROFILE_DTS_HD_HRA  50
+#define FF_PROFILE_DTS_HD_MA   60
+#define FF_PROFILE_MPEG2_422    0
+#define FF_PROFILE_MPEG2_HIGH   1
+#define FF_PROFILE_MPEG2_SS     2
+#define FF_PROFILE_MPEG2_SNR_SCALABLE  3
+#define FF_PROFILE_MPEG2_MAIN   4
+#define FF_PROFILE_MPEG2_SIMPLE 5
+#define FF_PROFILE_H264_CONSTRAINED  (1<<9)  // 8+1; constraint_set1_flag
+#define FF_PROFILE_H264_INTRA        (1<<11) // 8+3; constraint_set3_flag
+#define FF_PROFILE_H264_BASELINE             66
+#define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
+#define FF_PROFILE_H264_MAIN                 77
+#define FF_PROFILE_H264_EXTENDED             88
+#define FF_PROFILE_H264_HIGH                 100
+#define FF_PROFILE_H264_HIGH_10              110
+#define FF_PROFILE_H264_HIGH_10_INTRA        (110|FF_PROFILE_H264_INTRA)
+#define FF_PROFILE_H264_HIGH_422             122
+#define FF_PROFILE_H264_HIGH_422_INTRA       (122|FF_PROFILE_H264_INTRA)
+#define FF_PROFILE_H264_HIGH_444             144
+#define FF_PROFILE_H264_HIGH_444_PREDICTIVE  244
+#define FF_PROFILE_H264_HIGH_444_INTRA       (244|FF_PROFILE_H264_INTRA)
+#define FF_PROFILE_H264_CAVLC_444            44
+#define FF_PROFILE_VC1_SIMPLE   0
+#define FF_PROFILE_VC1_MAIN     1
+#define FF_PROFILE_VC1_COMPLEX  2
+#define FF_PROFILE_VC1_ADVANCED 3
+#define FF_PROFILE_MPEG4_SIMPLE                     0
+#define FF_PROFILE_MPEG4_SIMPLE_SCALABLE            1
+#define FF_PROFILE_MPEG4_CORE                       2
+#define FF_PROFILE_MPEG4_MAIN                       3
+#define FF_PROFILE_MPEG4_N_BIT                      4
+#define FF_PROFILE_MPEG4_SCALABLE_TEXTURE           5
+#define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION      6
+#define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE     7
+#define FF_PROFILE_MPEG4_HYBRID                     8
+#define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME         9
+#define FF_PROFILE_MPEG4_CORE_SCALABLE             10
+#define FF_PROFILE_MPEG4_ADVANCED_CODING           11
+#define FF_PROFILE_MPEG4_ADVANCED_CORE             12
+#define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
+#define FF_PROFILE_MPEG4_SIMPLE_STUDIO             14
+#define FF_PROFILE_MPEG4_ADVANCED_SIMPLE           15
+#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0   0
+#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1   1
+#define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION  2
+#define FF_PROFILE_JPEG2000_DCINEMA_2K              3
+#define FF_PROFILE_JPEG2000_DCINEMA_4K              4
+/**
+* level
+* - encoding: Set by user.
+* - decoding: Set by libavcodec.
+*/
+int level;
+#define FF_LEVEL_UNKNOWN -99
+/**
+* Skip loop filtering for selected frames.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+enum AVDiscard skip_loop_filter;
+/**
+* Skip IDCT/dequantization for selected frames.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+enum AVDiscard skip_idct;
+/**
+* Skip decoding for selected frames.
+* - encoding: unused
+* - decoding: Set by user.
+*/
+enum AVDiscard skip_frame;
+/**
+* Header containing style information for text subtitles.
+* For SUBTITLE_ASS subtitle type, it should contain the whole ASS
+* [Script Info] and [V4+ Styles] section, plus the [Events] line and
+* the Format line following. It shouldn't include any Dialogue line.
+* - encoding: Set/allocated/freed by user (before avcodec_open2())
+* - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
+*/
+uint8_t *subtitle_header;
+int subtitle_header_size;
+/**
+* Simulates errors in the bitstream to test error concealment.
+* - encoding: Set by user.
+* - decoding: unused
+*/
+int error_rate;
+/**
+* Current packet as passed into the decoder, to avoid having
+* to pass the packet into every function. Currently only valid
+* inside lavc and get/release_buffer callbacks.
+* - decoding: set by avcodec_decode_*, read by get_buffer() for setting pkt_pts
+* - encoding: unused
+*/
+AVPacket *pkt;
+/**
+* VBV delay coded in the last frame (in periods of a 27 MHz clock).
+* Used for compliant TS muxing.
+* - encoding: Set by libavcodec.
+* - decoding: unused.
+*/
+uint64_t vbv_delay;
+/**
+* Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
+* Code outside libavcodec should access this field using:
+* av_codec_{get,set}_pkt_timebase(avctx)
+* - encoding unused.
+* - decodimg set by user
+*/
+AVRational pkt_timebase;
+/**
+* AVCodecDescriptor
+* Code outside libavcodec should access this field using:
+* av_codec_{get,set}_codec_descriptor(avctx)
+* - encoding: unused.
+* - decoding: set by libavcodec.
+*/
+const AVCodecDescriptor *codec_descriptor;
+#if !FF_API_LOWRES
+/**
+* low resolution decoding, 1-> 1/2 size, 2->1/4 size
+* - encoding: unused
+* - decoding: Set by user.
+* Code outside libavcodec should access this field using:
+* av_codec_{get,set}_lowres(avctx)
+*/
+int lowres;
+#endif
+/**
+* Current statistics for PTS correction.
+* - decoding: maintained and used by libavcodec, not intended to be used by user apps
+* - encoding: unused
+*/
+int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
+int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
+int64_t pts_correction_last_pts;       /// PTS of the last frame
+int64_t pts_correction_last_dts;       /// DTS of the last frame
+/**
+* Character encoding of the input subtitles file.
+* - decoding: set by user
+* - encoding: unused
+*/
+char *sub_charenc;
+/**
+* Subtitles character encoding mode. Formats or codecs might be adjusting
+* this setting (if they are doing the conversion themselves for instance).
+* - decoding: set by libavcodec
+* - encoding: unused
+*/
+int sub_charenc_mode;
+#define FF_SUB_CHARENC_MODE_DO_NOTHING  -1  ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
+#define FF_SUB_CHARENC_MODE_AUTOMATIC    0  ///< libavcodec will select the mode itself
+#define FF_SUB_CHARENC_MODE_PRE_DECODER  1  ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
+} AVCodecContext;
+AVRational av_codec_get_pkt_timebase         (const AVCodecContext *avctx);
+void       av_codec_set_pkt_timebase         (AVCodecContext *avctx, AVRational val);
+const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
+void                     av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
+int  av_codec_get_lowres(const AVCodecContext *avctx);
+void av_codec_set_lowres(AVCodecContext *avctx, int val);
+/**
+* AVProfile.
+*/
+typedef struct AVProfile {
+int profile;
+const char *name; ///< short name for the profile
+} AVProfile;
+typedef struct AVCodecDefault AVCodecDefault;
+struct AVSubtitle;
+/**
+* AVCodec.
+*/
+typedef struct AVCodec {
+/**
+* Name of the codec implementation.
+* The name is globally unique among encoders and among decoders (but an
+* encoder and a decoder can share the same name).
+* This is the primary way to find a codec from the user perspective.
+*/
+const char *name;
+/**
+* Descriptive name for the codec, meant to be more human readable than name.
+* You should use the NULL_IF_CONFIG_SMALL() macro to define it.
+*/
+const char *long_name;
+enum AVMediaType type;
+enum AVCodecID id;
+/**
+* Codec capabilities.
+* see CODEC_CAP_*
+*/
+int capabilities;
+const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
+const enum AVPixelFormat *pix_fmts;     ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
+const int *supported_samplerates;       ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
+const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
+const uint64_t *channel_layouts;         ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
+uint8_t max_lowres;                     ///< maximum value for lowres supported by the decoder
+const AVClass *priv_class;              ///< AVClass for the private context
+const AVProfile *profiles;              ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
+/*****************************************************************
+* No fields below this line are part of the public API. They
+* may not be used outside of libavcodec and can be changed and
+* removed at will.
+* New public fields should be added right above.
+*****************************************************************
+*/
+int priv_data_size;
+struct AVCodec *next;
+/**
+* @name Frame-level threading support functions
+* @{
+*/
+/**
+* If defined, called on thread contexts when they are created.
+* If the codec allocates writable tables in init(), re-allocate them here.
+* priv_data will be set to a copy of the original.
+*/
+int (*init_thread_copy)(AVCodecContext *);
+/**
+* Copy necessary context variables from a previous thread context to the current one.
+* If not defined, the next thread will start automatically; otherwise, the codec
+* must call ff_thread_finish_setup().
+*
+* dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
+*/
+int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
+/** @} */
+/**
+* Private codec-specific defaults.
+*/
+const AVCodecDefault *defaults;
+/**
+* Initialize codec static data, called from avcodec_register().
+*/
+void (*init_static_data)(struct AVCodec *codec);
+int (*init)(AVCodecContext *);
+int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
+const struct AVSubtitle *sub);
+/**
+* Encode data to an AVPacket.
+*
+* @param      avctx          codec context
+* @param      avpkt          output AVPacket (may contain a user-provided buffer)
+* @param[in]  frame          AVFrame containing the raw data to be encoded
+* @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
+*                            non-empty packet was returned in avpkt.
+* @return 0 on success, negative error code on failure
+*/
+int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
+int *got_packet_ptr);
+int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
+int (*close)(AVCodecContext *);
+/**
+* Flush buffers.
+* Will be called when seeking
+*/
+void (*flush)(AVCodecContext *);
+} AVCodec;
+/**
+* AVHWAccel.
+*/
+typedef struct AVHWAccel {
+/**
+* Name of the hardware accelerated codec.
+* The name is globally unique among encoders and among decoders (but an
+* encoder and a decoder can share the same name).
+*/
+const char *name;
+/**
+* Type of codec implemented by the hardware accelerator.
+*
+* See AVMEDIA_TYPE_xxx
+*/
+enum AVMediaType type;
+/**
+* Codec implemented by the hardware accelerator.
+*
+* See AV_CODEC_ID_xxx
+*/
+enum AVCodecID id;
+/**
+* Supported pixel format.
+*
+* Only hardware accelerated formats are supported here.
+*/
+enum AVPixelFormat pix_fmt;
+/**
+* Hardware accelerated codec capabilities.
+* see FF_HWACCEL_CODEC_CAP_*
+*/
+int capabilities;
+struct AVHWAccel *next;
+/**
+* Called at the beginning of each frame or field picture.
+*
+* Meaningful frame information (codec specific) is guaranteed to
+* be parsed at this point. This function is mandatory.
+*
+* Note that buf can be NULL along with buf_size set to 0.
+* Otherwise, this means the whole frame is available at this point.
+*
+* @param avctx the codec context
+* @param buf the frame data buffer base
+* @param buf_size the size of the frame in bytes
+* @return zero if successful, a negative value otherwise
+*/
+int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
+/**
+* Callback for each slice.
+*
+* Meaningful slice information (codec specific) is guaranteed to
+* be parsed at this point. This function is mandatory.
+*
+* @param avctx the codec context
+* @param buf the slice data buffer base
+* @param buf_size the size of the slice in bytes
+* @return zero if successful, a negative value otherwise
+*/
+int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
+/**
+* Called at the end of each frame or field picture.
+*
+* The whole picture is parsed at this point and can now be sent
+* to the hardware accelerator. This function is mandatory.
+*
+* @param avctx the codec context
+* @return zero if successful, a negative value otherwise
+*/
+int (*end_frame)(AVCodecContext *avctx);
+/**
+* Size of HW accelerator private data.
+*
+* Private data is allocated with av_mallocz() before
+* AVCodecContext.get_buffer() and deallocated after
+* AVCodecContext.release_buffer().
+*/
+int priv_data_size;
+} AVHWAccel;
+/**
+* @defgroup lavc_picture AVPicture
+*
+* Functions for working with AVPicture
+* @{
+*/
+/**
+* four components are given, that's all.
+* the last component is alpha
+*/
+typedef struct AVPicture {
+uint8_t *data[AV_NUM_DATA_POINTERS];
+int linesize[AV_NUM_DATA_POINTERS];     ///< number of bytes per line
+} AVPicture;
+/**
+* @}
+*/
+enum AVSubtitleType {
+SUBTITLE_NONE,
+SUBTITLE_BITMAP,                ///< A bitmap, pict will be set
+/**
+* Plain text, the text field must be set by the decoder and is
+* authoritative. ass and pict fields may contain approximations.
+*/
+SUBTITLE_TEXT,
+/**
+* Formatted text, the ass field must be set by the decoder and is
+* authoritative. pict and text fields may contain approximations.
+*/
+SUBTITLE_ASS,
+};
+#define AV_SUBTITLE_FLAG_FORCED 0x00000001
+typedef struct AVSubtitleRect {
+int x;         ///< top left corner  of pict, undefined when pict is not set
+int y;         ///< top left corner  of pict, undefined when pict is not set
+int w;         ///< width            of pict, undefined when pict is not set
+int h;         ///< height           of pict, undefined when pict is not set
+int nb_colors; ///< number of colors in pict, undefined when pict is not set
+/**
+* data+linesize for the bitmap of this subtitle.
+* can be set for text/ass as well once they where rendered
+*/
+AVPicture pict;
+enum AVSubtitleType type;
+char *text;                     ///< 0 terminated plain UTF-8 text
+/**
+* 0 terminated ASS/SSA compatible event line.
+* The presentation of this is unaffected by the other values in this
+* struct.
+*/
+char *ass;
+int flags;
+} AVSubtitleRect;
+typedef struct AVSubtitle {
+uint16_t format; /* 0 = graphics */
+uint32_t start_display_time; /* relative to packet pts, in ms */
+uint32_t end_display_time; /* relative to packet pts, in ms */
+unsigned num_rects;
+AVSubtitleRect **rects;
+int64_t pts;    ///< Same as packet pts, in AV_TIME_BASE
+} AVSubtitle;
+/**
+* If c is NULL, returns the first registered codec,
+* if c is non-NULL, returns the next registered codec after c,
+* or NULL if c is the last one.
+*/
+AVCodec *av_codec_next(const AVCodec *c);
+/**
+* Return the LIBAVCODEC_VERSION_INT constant.
+*/
+unsigned avcodec_version(void);
+/**
+* Return the libavcodec build-time configuration.
+*/
+const char *avcodec_configuration(void);
+/**
+* Return the libavcodec license.
+*/
+const char *avcodec_license(void);
+/**
+* Register the codec codec and initialize libavcodec.
+*
+* @warning either this function or avcodec_register_all() must be called
+* before any other libavcodec functions.
+*
+* @see avcodec_register_all()
+*/
+void avcodec_register(AVCodec *codec);
+/**
+* Register all the codecs, parsers and bitstream filters which were enabled at
+* configuration time. If you do not call this function you can select exactly
+* which formats you want to support, by using the individual registration
+* functions.
+*
+* @see avcodec_register
+* @see av_register_codec_parser
+* @see av_register_bitstream_filter
+*/
+void avcodec_register_all(void);
+#if FF_API_ALLOC_CONTEXT
+/**
+* Allocate an AVCodecContext and set its fields to default values.  The
+* resulting struct can be deallocated by simply calling av_free().
+*
+* @return An AVCodecContext filled with default values or NULL on failure.
+* @see avcodec_get_context_defaults
+*
+* @deprecated use avcodec_alloc_context3()
+*/
+attribute_deprecated
+AVCodecContext *avcodec_alloc_context(void);
+/** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
+*  we WILL change its arguments and name a few times! */
+attribute_deprecated
+AVCodecContext *avcodec_alloc_context2(enum AVMediaType);
+/**
+* Set the fields of the given AVCodecContext to default values.
+*
+* @param s The AVCodecContext of which the fields should be set to default values.
+* @deprecated use avcodec_get_context_defaults3
+*/
+attribute_deprecated
+void avcodec_get_context_defaults(AVCodecContext *s);
+/** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
+*  we WILL change its arguments and name a few times! */
+attribute_deprecated
+void avcodec_get_context_defaults2(AVCodecContext *s, enum AVMediaType);
+#endif
+/**
+* Allocate an AVCodecContext and set its fields to default values.  The
+* resulting struct can be deallocated by calling avcodec_close() on it followed
+* by av_free().
+*
+* @param codec if non-NULL, allocate private data and initialize defaults
+*              for the given codec. It is illegal to then call avcodec_open2()
+*              with a different codec.
+*              If NULL, then the codec-specific defaults won't be initialized,
+*              which may result in suboptimal default settings (this is
+*              important mainly for encoders, e.g. libx264).
+*
+* @return An AVCodecContext filled with default values or NULL on failure.
+* @see avcodec_get_context_defaults
+*/
+AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
+/**
+* Set the fields of the given AVCodecContext to default values corresponding
+* to the given codec (defaults may be codec-dependent).
+*
+* Do not call this function if a non-NULL codec has been passed
+* to avcodec_alloc_context3() that allocated this AVCodecContext.
+* If codec is non-NULL, it is illegal to call avcodec_open2() with a
+* different codec on this AVCodecContext.
+*/
+int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
+/**
+* Get the AVClass for AVCodecContext. It can be used in combination with
+* AV_OPT_SEARCH_FAKE_OBJ for examining options.
+*
+* @see av_opt_find().
+*/
+const AVClass *avcodec_get_class(void);
+/**
+* Get the AVClass for AVFrame. It can be used in combination with
+* AV_OPT_SEARCH_FAKE_OBJ for examining options.
+*
+* @see av_opt_find().
+*/
+const AVClass *avcodec_get_frame_class(void);
+/**
+* Get the AVClass for AVSubtitleRect. It can be used in combination with
+* AV_OPT_SEARCH_FAKE_OBJ for examining options.
+*
+* @see av_opt_find().
+*/
+const AVClass *avcodec_get_subtitle_rect_class(void);
+/**
+* Copy the settings of the source AVCodecContext into the destination
+* AVCodecContext. The resulting destination codec context will be
+* unopened, i.e. you are required to call avcodec_open2() before you
+* can use this AVCodecContext to decode/encode video/audio data.
+*
+* @param dest target codec context, should be initialized with
+*             avcodec_alloc_context3(), but otherwise uninitialized
+* @param src source codec context
+* @return AVERROR() on error (e.g. memory allocation error), 0 on success
+*/
+int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
+/**
+* Allocate an AVFrame and set its fields to default values.  The resulting
+* struct must be freed using avcodec_free_frame().
+*
+* @return An AVFrame filled with default values or NULL on failure.
+* @see avcodec_get_frame_defaults
+*/
+AVFrame *avcodec_alloc_frame(void);
+/**
+* Set the fields of the given AVFrame to default values.
+*
+* @param frame The AVFrame of which the fields should be set to default values.
+*/
+void avcodec_get_frame_defaults(AVFrame *frame);
+/**
+* Free the frame and any dynamically allocated objects in it,
+* e.g. extended_data.
+*
+* @param frame frame to be freed. The pointer will be set to NULL.
+*
+* @warning this function does NOT free the data buffers themselves
+* (it does not know how, since they might have been allocated with
+*  a custom get_buffer()).
+*/
+void avcodec_free_frame(AVFrame **frame);
+#if FF_API_AVCODEC_OPEN
+/**
+* Initialize the AVCodecContext to use the given AVCodec. Prior to using this
+* function the context has to be allocated.
+*
+* The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
+* avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
+* retrieving a codec.
+*
+* @warning This function is not thread safe!
+*
+* @code
+* avcodec_register_all();
+* codec = avcodec_find_decoder(AV_CODEC_ID_H264);
+* if (!codec)
+*     exit(1);
+*
+* context = avcodec_alloc_context3(codec);
+*
+* if (avcodec_open(context, codec) < 0)
+*     exit(1);
+* @endcode
+*
+* @param avctx The context which will be set up to use the given codec.
+* @param codec The codec to use within the context.
+* @return zero on success, a negative value on error
+* @see avcodec_alloc_context3, avcodec_find_decoder, avcodec_find_encoder, avcodec_close
+*
+* @deprecated use avcodec_open2
+*/
+attribute_deprecated
+int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
+#endif
+/**
+* Initialize the AVCodecContext to use the given AVCodec. Prior to using this
+* function the context has to be allocated with avcodec_alloc_context3().
+*
+* The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
+* avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
+* retrieving a codec.
+*
+* @warning This function is not thread safe!
+*
+* @code
+* avcodec_register_all();
+* av_dict_set(&opts, "b", "2.5M", 0);
+* codec = avcodec_find_decoder(AV_CODEC_ID_H264);
+* if (!codec)
+*     exit(1);
+*
+* context = avcodec_alloc_context3(codec);
+*
+* if (avcodec_open2(context, codec, opts) < 0)
+*     exit(1);
+* @endcode
+*
+* @param avctx The context to initialize.
+* @param codec The codec to open this context for. If a non-NULL codec has been
+*              previously passed to avcodec_alloc_context3() or
+*              avcodec_get_context_defaults3() for this context, then this
+*              parameter MUST be either NULL or equal to the previously passed
+*              codec.
+* @param options A dictionary filled with AVCodecContext and codec-private options.
+*                On return this object will be filled with options that were not found.
+*
+* @return zero on success, a negative value on error
+* @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
+*      av_dict_set(), av_opt_find().
+*/
+int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
+/**
+* Close a given AVCodecContext and free all the data associated with it
+* (but not the AVCodecContext itself).
+*
+* Calling this function on an AVCodecContext that hasn't been opened will free
+* the codec-specific data allocated in avcodec_alloc_context3() /
+* avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
+* do nothing.
+*/
+int avcodec_close(AVCodecContext *avctx);
+/**
+* Free all allocated data in the given subtitle struct.
+*
+* @param sub AVSubtitle to free.
+*/
+void avsubtitle_free(AVSubtitle *sub);
+/**
+* @}
+*/
+/**
+* @addtogroup lavc_packet
+* @{
+*/
+#if FF_API_DESTRUCT_PACKET
+/**
+* Default packet destructor.
+* @deprecated use the AVBuffer API instead
+*/
+attribute_deprecated
+void av_destruct_packet(AVPacket *pkt);
+#endif
+/**
+* Initialize optional fields of a packet with default values.
+*
+* Note, this does not touch the data and size members, which have to be
+* initialized separately.
+*
+* @param pkt packet
+*/
+void av_init_packet(AVPacket *pkt);
+/**
+* Allocate the payload of a packet and initialize its fields with
+* default values.
+*
+* @param pkt packet
+* @param size wanted payload size
+* @return 0 if OK, AVERROR_xxx otherwise
+*/
+int av_new_packet(AVPacket *pkt, int size);
+/**
+* Reduce packet size, correctly zeroing padding
+*
+* @param pkt packet
+* @param size new size
+*/
+void av_shrink_packet(AVPacket *pkt, int size);
+/**
+* Increase packet size, correctly zeroing padding
+*
+* @param pkt packet
+* @param grow_by number of bytes by which to increase the size of the packet
+*/
+int av_grow_packet(AVPacket *pkt, int grow_by);
+/**
+* Initialize a reference-counted packet from av_malloc()ed data.
+*
+* @param pkt packet to be initialized. This function will set the data, size,
+*        buf and destruct fields, all others are left untouched.
+* @param data Data allocated by av_malloc() to be used as packet data. If this
+*        function returns successfully, the data is owned by the underlying AVBuffer.
+*        The caller may not access the data through other means.
+* @param size size of data in bytes, without the padding. I.e. the full buffer
+*        size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
+*
+* @return 0 on success, a negative AVERROR on error
+*/
+int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
+/**
+* @warning This is a hack - the packet memory allocation stuff is broken. The
+* packet is allocated if it was not really allocated.
+*/
+int av_dup_packet(AVPacket *pkt);
+/**
+* Copy packet, including contents
+*
+* @return 0 on success, negative AVERROR on fail
+*/
+int av_copy_packet(AVPacket *dst, AVPacket *src);
+/**
+* Copy packet side data
+*
+* @return 0 on success, negative AVERROR on fail
+*/
+int av_copy_packet_side_data(AVPacket *dst, AVPacket *src);
+/**
+* Free a packet.
+*
+* @param pkt packet to free
+*/
+void av_free_packet(AVPacket *pkt);
+/**
+* Allocate new information of a packet.
+*
+* @param pkt packet
+* @param type side information type
+* @param size side information size
+* @return pointer to fresh allocated data or NULL otherwise
+*/
+uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
+int size);
+/**
+* Shrink the already allocated side data buffer
+*
+* @param pkt packet
+* @param type side information type
+* @param size new side information size
+* @return 0 on success, < 0 on failure
+*/
+int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
+int size);
+/**
+* Get side information from packet.
+*
+* @param pkt packet
+* @param type desired side information type
+* @param size pointer for side information size to store (optional)
+* @return pointer to data if present or NULL otherwise
+*/
+uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
+int *size);
+int av_packet_merge_side_data(AVPacket *pkt);
+int av_packet_split_side_data(AVPacket *pkt);
+/**
+* @}
+*/
+/**
+* @addtogroup lavc_decoding
+* @{
+*/
+/**
+* Find a registered decoder with a matching codec ID.
+*
+* @param id AVCodecID of the requested decoder
+* @return A decoder if one was found, NULL otherwise.
+*/
+AVCodec *avcodec_find_decoder(enum AVCodecID id);
+/**
+* Find a registered decoder with the specified name.
+*
+* @param name name of the requested decoder
+* @return A decoder if one was found, NULL otherwise.
+*/
+AVCodec *avcodec_find_decoder_by_name(const char *name);
+#if FF_API_GET_BUFFER
+attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
+attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
+attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
+#endif
+/**
+* The default callback for AVCodecContext.get_buffer2(). It is made public so
+* it can be called by custom get_buffer2() implementations for decoders without
+* CODEC_CAP_DR1 set.
+*/
+int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
+/**
+* Return the amount of padding in pixels which the get_buffer callback must
+* provide around the edge of the image for codecs which do not have the
+* CODEC_FLAG_EMU_EDGE flag.
+*
+* @return Required padding in pixels.
+*/
+unsigned avcodec_get_edge_width(void);
+/**
+* Modify width and height values so that they will result in a memory
+* buffer that is acceptable for the codec if you do not use any horizontal
+* padding.
+*
+* May only be used if a codec with CODEC_CAP_DR1 has been opened.
+* If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
+* according to avcodec_get_edge_width() before.
+*/
+void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
+/**
+* Modify width and height values so that they will result in a memory
+* buffer that is acceptable for the codec if you also ensure that all
+* line sizes are a multiple of the respective linesize_align[i].
+*
+* May only be used if a codec with CODEC_CAP_DR1 has been opened.
+* If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
+* according to avcodec_get_edge_width() before.
+*/
+void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
+int linesize_align[AV_NUM_DATA_POINTERS]);
+#if FF_API_OLD_DECODE_AUDIO
+/**
+* Wrapper function which calls avcodec_decode_audio4.
+*
+* @deprecated Use avcodec_decode_audio4 instead.
+*
+* Decode the audio frame of size avpkt->size from avpkt->data into samples.
+* Some decoders may support multiple frames in a single AVPacket, such
+* decoders would then just decode the first frame. In this case,
+* avcodec_decode_audio3 has to be called again with an AVPacket that contains
+* the remaining data in order to decode the second frame etc.
+* If no frame
+* could be outputted, frame_size_ptr is zero. Otherwise, it is the
+* decompressed frame size in bytes.
+*
+* @warning You must set frame_size_ptr to the allocated size of the
+* output buffer before calling avcodec_decode_audio3().
+*
+* @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
+* the actual read bytes because some optimized bitstream readers read 32 or 64
+* bits at once and could read over the end.
+*
+* @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
+* no overreading happens for damaged MPEG streams.
+*
+* @warning You must not provide a custom get_buffer() when using
+* avcodec_decode_audio3().  Doing so will override it with
+* avcodec_default_get_buffer.  Use avcodec_decode_audio4() instead,
+* which does allow the application to provide a custom get_buffer().
+*
+* @note You might have to align the input buffer avpkt->data and output buffer
+* samples. The alignment requirements depend on the CPU: On some CPUs it isn't
+* necessary at all, on others it won't work at all if not aligned and on others
+* it will work but it will have an impact on performance.
+*
+* In practice, avpkt->data should have 4 byte alignment at minimum and
+* samples should be 16 byte aligned unless the CPU doesn't need it
+* (AltiVec and SSE do).
+*
+* @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
+* between input and output, these need to be fed with avpkt->data=NULL,
+* avpkt->size=0 at the end to return the remaining frames.
+*
+* @param avctx the codec context
+* @param[out] samples the output buffer, sample type in avctx->sample_fmt
+*                     If the sample format is planar, each channel plane will
+*                     be the same size, with no padding between channels.
+* @param[in,out] frame_size_ptr the output buffer size in bytes
+* @param[in] avpkt The input AVPacket containing the input buffer.
+*            You can create such packet with av_init_packet() and by then setting
+*            data and size, some decoders might in addition need other fields.
+*            All decoders are designed to use the least fields possible though.
+* @return On error a negative value is returned, otherwise the number of bytes
+* used or zero if no frame data was decompressed (used) from the input AVPacket.
+*/
+attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
+int *frame_size_ptr,
+AVPacket *avpkt);
+#endif
+/**
+* Decode the audio frame of size avpkt->size from avpkt->data into frame.
+*
+* Some decoders may support multiple frames in a single AVPacket. Such
+* decoders would then just decode the first frame. In this case,
+* avcodec_decode_audio4 has to be called again with an AVPacket containing
+* the remaining data in order to decode the second frame, etc...
+* Even if no frames are returned, the packet needs to be fed to the decoder
+* with remaining data until it is completely consumed or an error occurs.
+*
+* @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
+*          larger than the actual read bytes because some optimized bitstream
+*          readers read 32 or 64 bits at once and could read over the end.
+*
+* @note You might have to align the input buffer. The alignment requirements
+*       depend on the CPU and the decoder.
+*
+* @param      avctx the codec context
+* @param[out] frame The AVFrame in which to store decoded audio samples.
+*                   The decoder will allocate a buffer for the decoded frame by
+*                   calling the AVCodecContext.get_buffer2() callback.
+*                   When AVCodecContext.refcounted_frames is set to 1, the frame is
+*                   reference counted and the returned reference belongs to the
+*                   caller. The caller must release the frame using av_frame_unref()
+*                   when the frame is no longer needed. The caller may safely write
+*                   to the frame if av_frame_is_writable() returns 1.
+*                   When AVCodecContext.refcounted_frames is set to 0, the returned
+*                   reference belongs to the decoder and is valid only until the
+*                   next call to this function or until closing the decoder.
+*                   The caller may not write to it.
+* @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
+*                           non-zero.
+* @param[in]  avpkt The input AVPacket containing the input buffer.
+*                   At least avpkt->data and avpkt->size should be set. Some
+*                   decoders might also require additional fields to be set.
+* @return A negative error code is returned if an error occurred during
+*         decoding, otherwise the number of bytes consumed from the input
+*         AVPacket is returned.
+*/
+int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
+int *got_frame_ptr, const AVPacket *avpkt);
+/**
+* Decode the video frame of size avpkt->size from avpkt->data into picture.
+* Some decoders may support multiple frames in a single AVPacket, such
+* decoders would then just decode the first frame.
+*
+* @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
+* the actual read bytes because some optimized bitstream readers read 32 or 64
+* bits at once and could read over the end.
+*
+* @warning The end of the input buffer buf should be set to 0 to ensure that
+* no overreading happens for damaged MPEG streams.
+*
+* @note You might have to align the input buffer avpkt->data.
+* The alignment requirements depend on the CPU: on some CPUs it isn't
+* necessary at all, on others it won't work at all if not aligned and on others
+* it will work but it will have an impact on performance.
+*
+* In practice, avpkt->data should have 4 byte alignment at minimum.
+*
+* @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
+* between input and output, these need to be fed with avpkt->data=NULL,
+* avpkt->size=0 at the end to return the remaining frames.
+*
+* @param avctx the codec context
+* @param[out] picture The AVFrame in which the decoded video frame will be stored.
+*             Use av_frame_alloc() to get an AVFrame. The codec will
+*             allocate memory for the actual bitmap by calling the
+*             AVCodecContext.get_buffer2() callback.
+*             When AVCodecContext.refcounted_frames is set to 1, the frame is
+*             reference counted and the returned reference belongs to the
+*             caller. The caller must release the frame using av_frame_unref()
+*             when the frame is no longer needed. The caller may safely write
+*             to the frame if av_frame_is_writable() returns 1.
+*             When AVCodecContext.refcounted_frames is set to 0, the returned
+*             reference belongs to the decoder and is valid only until the
+*             next call to this function or until closing the decoder. The
+*             caller may not write to it.
+*
+* @param[in] avpkt The input AVpacket containing the input buffer.
+*            You can create such packet with av_init_packet() and by then setting
+*            data and size, some decoders might in addition need other fields like
+*            flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
+*            fields possible.
+* @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
+* @return On error a negative value is returned, otherwise the number of bytes
+* used or zero if no frame could be decompressed.
+*/
+int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
+int *got_picture_ptr,
+const AVPacket *avpkt);
+/**
+* Decode a subtitle message.
+* Return a negative value on error, otherwise return the number of bytes used.
+* If no subtitle could be decompressed, got_sub_ptr is zero.
+* Otherwise, the subtitle is stored in *sub.
+* Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
+* simplicity, because the performance difference is expect to be negligible
+* and reusing a get_buffer written for video codecs would probably perform badly
+* due to a potentially very different allocation pattern.
+*
+* @param avctx the codec context
+* @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
+freed with avsubtitle_free if *got_sub_ptr is set.
+* @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
+* @param[in] avpkt The input AVPacket containing the input buffer.
+*/
+int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
+int *got_sub_ptr,
+AVPacket *avpkt);
+/**
+* @defgroup lavc_parsing Frame parsing
+* @{
+*/
+typedef struct AVCodecParserContext {
+void *priv_data;
+struct AVCodecParser *parser;
+int64_t frame_offset; /* offset of the current frame */
+int64_t cur_offset; /* current offset
+(incremented by each av_parser_parse()) */
+int64_t next_frame_offset; /* offset of the next frame */
+/* video info */
+int pict_type; /* XXX: Put it back in AVCodecContext. */
+/**
+* This field is used for proper frame duration computation in lavf.
+* It signals, how much longer the frame duration of the current frame
+* is compared to normal frame duration.
+*
+* frame_duration = (1 + repeat_pict) * time_base
+*
+* It is used by codecs like H.264 to display telecined material.
+*/
+int repeat_pict; /* XXX: Put it back in AVCodecContext. */
+int64_t pts;     /* pts of the current frame */
+int64_t dts;     /* dts of the current frame */
+/* private data */
+int64_t last_pts;
+int64_t last_dts;
+int fetch_timestamp;
+#define AV_PARSER_PTS_NB 4
+int cur_frame_start_index;
+int64_t cur_frame_offset[AV_PARSER_PTS_NB];
+int64_t cur_frame_pts[AV_PARSER_PTS_NB];
+int64_t cur_frame_dts[AV_PARSER_PTS_NB];
+int flags;
+#define PARSER_FLAG_COMPLETE_FRAMES           0x0001
+#define PARSER_FLAG_ONCE                      0x0002
+/// Set if the parser has a valid file offset
+#define PARSER_FLAG_FETCHED_OFFSET            0x0004
+#define PARSER_FLAG_USE_CODEC_TS              0x1000
+int64_t offset;      ///< byte offset from starting packet start
+int64_t cur_frame_end[AV_PARSER_PTS_NB];
+/**
+* Set by parser to 1 for key frames and 0 for non-key frames.
+* It is initialized to -1, so if the parser doesn't set this flag,
+* old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
+* will be used.
+*/
+int key_frame;
+/**
+* Time difference in stream time base units from the pts of this
+* packet to the point at which the output from the decoder has converged
+* independent from the availability of previous frames. That is, the
+* frames are virtually identical no matter if decoding started from
+* the very first frame or from this keyframe.
+* Is AV_NOPTS_VALUE if unknown.
+* This field is not the display duration of the current frame.
+* This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
+* set.
+*
+* The purpose of this field is to allow seeking in streams that have no
+* keyframes in the conventional sense. It corresponds to the
+* recovery point SEI in H.264 and match_time_delta in NUT. It is also
+* essential for some types of subtitle streams to ensure that all
+* subtitles are correctly displayed after seeking.
+*/
+int64_t convergence_duration;
+// Timestamp generation support:
+/**
+* Synchronization point for start of timestamp generation.
+*
+* Set to >0 for sync point, 0 for no sync point and <0 for undefined
+* (default).
+*
+* For example, this corresponds to presence of H.264 buffering period
+* SEI message.
+*/
+int dts_sync_point;
+/**
+* Offset of the current timestamp against last timestamp sync point in
+* units of AVCodecContext.time_base.
+*
+* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
+* contain a valid timestamp offset.
+*
+* Note that the timestamp of sync point has usually a nonzero
+* dts_ref_dts_delta, which refers to the previous sync point. Offset of
+* the next frame after timestamp sync point will be usually 1.
+*
+* For example, this corresponds to H.264 cpb_removal_delay.
+*/
+int dts_ref_dts_delta;
+/**
+* Presentation delay of current frame in units of AVCodecContext.time_base.
+*
+* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
+* contain valid non-negative timestamp delta (presentation time of a frame
+* must not lie in the past).
+*
+* This delay represents the difference between decoding and presentation
+* time of the frame.
+*
+* For example, this corresponds to H.264 dpb_output_delay.
+*/
+int pts_dts_delta;
+/**
+* Position of the packet in file.
+*
+* Analogous to cur_frame_pts/dts
+*/
+int64_t cur_frame_pos[AV_PARSER_PTS_NB];
+/**
+* Byte position of currently parsed frame in stream.
+*/
+int64_t pos;
+/**
+* Previous frame byte position.
+*/
+int64_t last_pos;
+/**
+* Duration of the current frame.
+* For audio, this is in units of 1 / AVCodecContext.sample_rate.
+* For all other types, this is in units of AVCodecContext.time_base.
+*/
+int duration;
+enum AVFieldOrder field_order;
+} AVCodecParserContext;
+typedef struct AVCodecParser {
+int codec_ids[5]; /* several codec IDs are permitted */
+int priv_data_size;
+int (*parser_init)(AVCodecParserContext *s);
+int (*parser_parse)(AVCodecParserContext *s,
+AVCodecContext *avctx,
+const uint8_t **poutbuf, int *poutbuf_size,
+const uint8_t *buf, int buf_size);
+void (*parser_close)(AVCodecParserContext *s);
+int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
+struct AVCodecParser *next;
+} AVCodecParser;
+AVCodecParser *av_parser_next(AVCodecParser *c);
+void av_register_codec_parser(AVCodecParser *parser);
+AVCodecParserContext *av_parser_init(int codec_id);
+/**
+* Parse a packet.
+*
+* @param s             parser context.
+* @param avctx         codec context.
+* @param poutbuf       set to pointer to parsed buffer or NULL if not yet finished.
+* @param poutbuf_size  set to size of parsed buffer or zero if not yet finished.
+* @param buf           input buffer.
+* @param buf_size      input length, to signal EOF, this should be 0 (so that the last frame can be output).
+* @param pts           input presentation timestamp.
+* @param dts           input decoding timestamp.
+* @param pos           input byte position in stream.
+* @return the number of bytes of the input bitstream used.
+*
+* Example:
+* @code
+*   while(in_len){
+*       len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
+*                                        in_data, in_len,
+*                                        pts, dts, pos);
+*       in_data += len;
+*       in_len  -= len;
+*
+*       if(size)
+*          decode_frame(data, size);
+*   }
+* @endcode
+*/
+int av_parser_parse2(AVCodecParserContext *s,
+AVCodecContext *avctx,
+uint8_t **poutbuf, int *poutbuf_size,
+const uint8_t *buf, int buf_size,
+int64_t pts, int64_t dts,
+int64_t pos);
+/**
+* @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
+* @deprecated use AVBitStreamFilter
+*/
+int av_parser_change(AVCodecParserContext *s,
+AVCodecContext *avctx,
+uint8_t **poutbuf, int *poutbuf_size,
+const uint8_t *buf, int buf_size, int keyframe);
+void av_parser_close(AVCodecParserContext *s);
+/**
+* @}
+* @}
+*/
+/**
+* @addtogroup lavc_encoding
+* @{
+*/
+/**
+* Find a registered encoder with a matching codec ID.
+*
+* @param id AVCodecID of the requested encoder
+* @return An encoder if one was found, NULL otherwise.
+*/
+AVCodec *avcodec_find_encoder(enum AVCodecID id);
+/**
+* Find a registered encoder with the specified name.
+*
+* @param name name of the requested encoder
+* @return An encoder if one was found, NULL otherwise.
+*/
+AVCodec *avcodec_find_encoder_by_name(const char *name);
+#if FF_API_OLD_ENCODE_AUDIO
+/**
+* Encode an audio frame from samples into buf.
+*
+* @deprecated Use avcodec_encode_audio2 instead.
+*
+* @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
+* However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
+* will know how much space is needed because it depends on the value passed
+* in buf_size as described below. In that case a lower value can be used.
+*
+* @param avctx the codec context
+* @param[out] buf the output buffer
+* @param[in] buf_size the output buffer size
+* @param[in] samples the input buffer containing the samples
+* The number of samples read from this buffer is frame_size*channels,
+* both of which are defined in avctx.
+* For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
+* samples read from samples is equal to:
+* buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
+* This also implies that av_get_bits_per_sample() must not return 0 for these
+* codecs.
+* @return On error a negative value is returned, on success zero or the number
+* of bytes used to encode the data read from the input buffer.
+*/
+int attribute_deprecated avcodec_encode_audio(AVCodecContext *avctx,
+uint8_t *buf, int buf_size,
+const short *samples);
+#endif
+/**
+* Encode a frame of audio.
+*
+* Takes input samples from frame and writes the next output packet, if
+* available, to avpkt. The output packet does not necessarily contain data for
+* the most recent frame, as encoders can delay, split, and combine input frames
+* internally as needed.
+*
+* @param avctx     codec context
+* @param avpkt     output AVPacket.
+*                  The user can supply an output buffer by setting
+*                  avpkt->data and avpkt->size prior to calling the
+*                  function, but if the size of the user-provided data is not
+*                  large enough, encoding will fail. If avpkt->data and
+*                  avpkt->size are set, avpkt->destruct must also be set. All
+*                  other AVPacket fields will be reset by the encoder using
+*                  av_init_packet(). If avpkt->data is NULL, the encoder will
+*                  allocate it. The encoder will set avpkt->size to the size
+*                  of the output packet.
+*
+*                  If this function fails or produces no output, avpkt will be
+*                  freed using av_free_packet() (i.e. avpkt->destruct will be
+*                  called to free the user supplied buffer).
+* @param[in] frame AVFrame containing the raw audio data to be encoded.
+*                  May be NULL when flushing an encoder that has the
+*                  CODEC_CAP_DELAY capability set.
+*                  If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
+*                  can have any number of samples.
+*                  If it is not set, frame->nb_samples must be equal to
+*                  avctx->frame_size for all frames except the last.
+*                  The final frame may be smaller than avctx->frame_size.
+* @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
+*                            output packet is non-empty, and to 0 if it is
+*                            empty. If the function returns an error, the
+*                            packet can be assumed to be invalid, and the
+*                            value of got_packet_ptr is undefined and should
+*                            not be used.
+* @return          0 on success, negative error code on failure
+*/
+int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
+const AVFrame *frame, int *got_packet_ptr);
+#if FF_API_OLD_ENCODE_VIDEO
+/**
+* @deprecated use avcodec_encode_video2() instead.
+*
+* Encode a video frame from pict into buf.
+* The input picture should be
+* stored using a specific format, namely avctx.pix_fmt.
+*
+* @param avctx the codec context
+* @param[out] buf the output buffer for the bitstream of encoded frame
+* @param[in] buf_size the size of the output buffer in bytes
+* @param[in] pict the input picture to encode
+* @return On error a negative value is returned, on success zero or the number
+* of bytes used from the output buffer.
+*/
+attribute_deprecated
+int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
+const AVFrame *pict);
+#endif
+/**
+* Encode a frame of video.
+*
+* Takes input raw video data from frame and writes the next output packet, if
+* available, to avpkt. The output packet does not necessarily contain data for
+* the most recent frame, as encoders can delay and reorder input frames
+* internally as needed.
+*
+* @param avctx     codec context
+* @param avpkt     output AVPacket.
+*                  The user can supply an output buffer by setting
+*                  avpkt->data and avpkt->size prior to calling the
+*                  function, but if the size of the user-provided data is not
+*                  large enough, encoding will fail. All other AVPacket fields
+*                  will be reset by the encoder using av_init_packet(). If
+*                  avpkt->data is NULL, the encoder will allocate it.
+*                  The encoder will set avpkt->size to the size of the
+*                  output packet. The returned data (if any) belongs to the
+*                  caller, he is responsible for freeing it.
+*
+*                  If this function fails or produces no output, avpkt will be
+*                  freed using av_free_packet() (i.e. avpkt->destruct will be
+*                  called to free the user supplied buffer).
+* @param[in] frame AVFrame containing the raw video data to be encoded.
+*                  May be NULL when flushing an encoder that has the
+*                  CODEC_CAP_DELAY capability set.
+* @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
+*                            output packet is non-empty, and to 0 if it is
+*                            empty. If the function returns an error, the
+*                            packet can be assumed to be invalid, and the
+*                            value of got_packet_ptr is undefined and should
+*                            not be used.
+* @return          0 on success, negative error code on failure
+*/
+int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
+const AVFrame *frame, int *got_packet_ptr);
+int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
+const AVSubtitle *sub);
+/**
+* @}
+*/
+#if FF_API_AVCODEC_RESAMPLE
+/**
+* @defgroup lavc_resample Audio resampling
+* @ingroup libavc
+* @deprecated use libswresample instead
+*
+* @{
+*/
+struct ReSampleContext;
+struct AVResampleContext;
+typedef struct ReSampleContext ReSampleContext;
+/**
+*  Initialize audio resampling context.
+*
+* @param output_channels  number of output channels
+* @param input_channels   number of input channels
+* @param output_rate      output sample rate
+* @param input_rate       input sample rate
+* @param sample_fmt_out   requested output sample format
+* @param sample_fmt_in    input sample format
+* @param filter_length    length of each FIR filter in the filterbank relative to the cutoff frequency
+* @param log2_phase_count log2 of the number of entries in the polyphase filterbank
+* @param linear           if 1 then the used FIR filter will be linearly interpolated
+between the 2 closest, if 0 the closest will be used
+* @param cutoff           cutoff frequency, 1.0 corresponds to half the output sampling rate
+* @return allocated ReSampleContext, NULL if error occurred
+*/
+attribute_deprecated
+ReSampleContext *av_audio_resample_init(int output_channels, int input_channels,
+int output_rate, int input_rate,
+enum AVSampleFormat sample_fmt_out,
+enum AVSampleFormat sample_fmt_in,
+int filter_length, int log2_phase_count,
+int linear, double cutoff);
+attribute_deprecated
+int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
+/**
+* Free resample context.
+*
+* @param s a non-NULL pointer to a resample context previously
+*          created with av_audio_resample_init()
+*/
+attribute_deprecated
+void audio_resample_close(ReSampleContext *s);
+/**
+* Initialize an audio resampler.
+* Note, if either rate is not an integer then simply scale both rates up so they are.
+* @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
+* @param log2_phase_count log2 of the number of entries in the polyphase filterbank
+* @param linear If 1 then the used FIR filter will be linearly interpolated
+between the 2 closest, if 0 the closest will be used
+* @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
+*/
+attribute_deprecated
+struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
+/**
+* Resample an array of samples using a previously configured context.
+* @param src an array of unconsumed samples
+* @param consumed the number of samples of src which have been consumed are returned here
+* @param src_size the number of unconsumed samples available
+* @param dst_size the amount of space in samples available in dst
+* @param update_ctx If this is 0 then the context will not be modified, that way several channels can be resampled with the same context.
+* @return the number of samples written in dst or -1 if an error occurred
+*/
+attribute_deprecated
+int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
+/**
+* Compensate samplerate/timestamp drift. The compensation is done by changing
+* the resampler parameters, so no audible clicks or similar distortions occur
+* @param compensation_distance distance in output samples over which the compensation should be performed
+* @param sample_delta number of output samples which should be output less
+*
+* example: av_resample_compensate(c, 10, 500)
+* here instead of 510 samples only 500 samples would be output
+*
+* note, due to rounding the actual compensation might be slightly different,
+* especially if the compensation_distance is large and the in_rate used during init is small
+*/
+attribute_deprecated
+void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
+attribute_deprecated
+void av_resample_close(struct AVResampleContext *c);
+/**
+* @}
+*/
+#endif
+/**
+* @addtogroup lavc_picture
+* @{
+*/
+/**
+* Allocate memory for a picture.  Call avpicture_free() to free it.
+*
+* @see avpicture_fill()
+*
+* @param picture the picture to be filled in
+* @param pix_fmt the format of the picture
+* @param width the width of the picture
+* @param height the height of the picture
+* @return zero if successful, a negative value if not
+*/
+int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
+/**
+* Free a picture previously allocated by avpicture_alloc().
+* The data buffer used by the AVPicture is freed, but the AVPicture structure
+* itself is not.
+*
+* @param picture the AVPicture to be freed
+*/
+void avpicture_free(AVPicture *picture);
+/**
+* Fill in the AVPicture fields, always assume a linesize alignment of
+* 1.
+*
+* @see av_image_fill_arrays()
+*/
+int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
+enum AVPixelFormat pix_fmt, int width, int height);
+/**
+* Copy pixel data from an AVPicture into a buffer, always assume a
+* linesize alignment of 1.
+*
+* @see av_image_copy_to_buffer()
+*/
+int avpicture_layout(const AVPicture* src, enum AVPixelFormat pix_fmt,
+int width, int height,
+unsigned char *dest, int dest_size);
+/**
+* Calculate the size in bytes that a picture of the given width and height
+* would occupy if stored in the given picture format.
+* Always assume a linesize alignment of 1.
+*
+* @see av_image_get_buffer_size().
+*/
+int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
+#if FF_API_DEINTERLACE
+/**
+*  deinterlace - if not supported return -1
+*
+* @deprecated - use yadif (in libavfilter) instead
+*/
+attribute_deprecated
+int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
+enum AVPixelFormat pix_fmt, int width, int height);
+#endif
+/**
+* Copy image src to dst. Wraps av_image_copy().
+*/
+void av_picture_copy(AVPicture *dst, const AVPicture *src,
+enum AVPixelFormat pix_fmt, int width, int height);
+/**
+* Crop image top and left side.
+*/
+int av_picture_crop(AVPicture *dst, const AVPicture *src,
+enum AVPixelFormat pix_fmt, int top_band, int left_band);
+/**
+* Pad image.
+*/
+int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
+int padtop, int padbottom, int padleft, int padright, int *color);
+/**
+* @}
+*/
+/**
+* @defgroup lavc_misc Utility functions
+* @ingroup libavc
+*
+* Miscellaneous utility functions related to both encoding and decoding
+* (or neither).
+* @{
+*/
+/**
+* @defgroup lavc_misc_pixfmt Pixel formats
+*
+* Functions for working with pixel formats.
+* @{
+*/
+/**
+* Utility function to access log2_chroma_w log2_chroma_h from
+* the pixel format AVPixFmtDescriptor.
+*
+* This function asserts that pix_fmt is valid. See av_pix_fmt_get_chroma_sub_sample
+* for one that returns a failure code and continues in case of invalid
+* pix_fmts.
+*
+* @param[in]  pix_fmt the pixel format
+* @param[out] h_shift store log2_chroma_w
+* @param[out] v_shift store log2_chroma_h
+*
+* @see av_pix_fmt_get_chroma_sub_sample
+*/
+void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
+/**
+* Return a value representing the fourCC code associated to the
+* pixel format pix_fmt, or 0 if no associated fourCC code can be
+* found.
+*/
+unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
+#define FF_LOSS_RESOLUTION  0x0001 /**< loss due to resolution change */
+#define FF_LOSS_DEPTH       0x0002 /**< loss due to color depth change */
+#define FF_LOSS_COLORSPACE  0x0004 /**< loss due to color space conversion */
+#define FF_LOSS_ALPHA       0x0008 /**< loss of alpha bits */
+#define FF_LOSS_COLORQUANT  0x0010 /**< loss due to color quantization */
+#define FF_LOSS_CHROMA      0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
+/**
+* Compute what kind of losses will occur when converting from one specific
+* pixel format to another.
+* When converting from one pixel format to another, information loss may occur.
+* For example, when converting from RGB24 to GRAY, the color information will
+* be lost. Similarly, other losses occur when converting from some formats to
+* other formats. These losses can involve loss of chroma, but also loss of
+* resolution, loss of color depth, loss due to the color space conversion, loss
+* of the alpha bits or loss due to color quantization.
+* avcodec_get_fix_fmt_loss() informs you about the various types of losses
+* which will occur when converting from one pixel format to another.
+*
+* @param[in] dst_pix_fmt destination pixel format
+* @param[in] src_pix_fmt source pixel format
+* @param[in] has_alpha Whether the source pixel format alpha channel is used.
+* @return Combination of flags informing you what kind of losses will occur
+* (maximum loss for an invalid dst_pix_fmt).
+*/
+int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
+int has_alpha);
+/**
+* Find the best pixel format to convert to given a certain source pixel
+* format.  When converting from one pixel format to another, information loss
+* may occur.  For example, when converting from RGB24 to GRAY, the color
+* information will be lost. Similarly, other losses occur when converting from
+* some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
+* the given pixel formats should be used to suffer the least amount of loss.
+* The pixel formats from which it chooses one, are determined by the
+* pix_fmt_list parameter.
+*
+*
+* @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
+* @param[in] src_pix_fmt source pixel format
+* @param[in] has_alpha Whether the source pixel format alpha channel is used.
+* @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
+* @return The best pixel format to convert to or -1 if none was found.
+*/
+enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(enum AVPixelFormat *pix_fmt_list,
+enum AVPixelFormat src_pix_fmt,
+int has_alpha, int *loss_ptr);
+/**
+* Find the best pixel format to convert to given a certain source pixel
+* format and a selection of two destination pixel formats. When converting from
+* one pixel format to another, information loss may occur.  For example, when converting
+* from RGB24 to GRAY, the color information will be lost. Similarly, other losses occur when
+* converting from some formats to other formats. avcodec_find_best_pix_fmt_of_2() selects which of
+* the given pixel formats should be used to suffer the least amount of loss.
+*
+* If one of the destination formats is AV_PIX_FMT_NONE the other pixel format (if valid) will be
+* returned.
+*
+* @code
+* src_pix_fmt = AV_PIX_FMT_YUV420P;
+* dst_pix_fmt1= AV_PIX_FMT_RGB24;
+* dst_pix_fmt2= AV_PIX_FMT_GRAY8;
+* dst_pix_fmt3= AV_PIX_FMT_RGB8;
+* loss= FF_LOSS_CHROMA; // don't care about chroma loss, so chroma loss will be ignored.
+* dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt1, dst_pix_fmt2, src_pix_fmt, alpha, &loss);
+* dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt, dst_pix_fmt3, src_pix_fmt, alpha, &loss);
+* @endcode
+*
+* @param[in] dst_pix_fmt1 One of the two destination pixel formats to choose from
+* @param[in] dst_pix_fmt2 The other of the two destination pixel formats to choose from
+* @param[in] src_pix_fmt Source pixel format
+* @param[in] has_alpha Whether the source pixel format alpha channel is used.
+* @param[in, out] loss_ptr Combination of loss flags. In: selects which of the losses to ignore, i.e.
+*                               NULL or value of zero means we care about all losses. Out: the loss
+*                               that occurs when converting from src to selected dst pixel format.
+* @return The best pixel format to convert to or -1 if none was found.
+*/
+enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
+enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
+attribute_deprecated
+#if AV_HAVE_INCOMPATIBLE_FORK_ABI
+enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat *pix_fmt_list,
+enum AVPixelFormat src_pix_fmt,
+int has_alpha, int *loss_ptr);
+#else
+enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
+enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
+#endif
+enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
+/**
+* @}
+*/
+void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
+/**
+* Put a string representing the codec tag codec_tag in buf.
+*
+* @param buf_size size in bytes of buf
+* @return the length of the string that would have been generated if
+* enough space had been available, excluding the trailing null
+*/
+size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
+void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
+/**
+* Return a name for the specified profile, if available.
+*
+* @param codec the codec that is searched for the given profile
+* @param profile the profile value for which a name is requested
+* @return A name for the profile if found, NULL otherwise.
+*/
+const char *av_get_profile_name(const AVCodec *codec, int profile);
+int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
+int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
+//FIXME func typedef
+/**
+* Fill AVFrame audio data and linesize pointers.
+*
+* The buffer buf must be a preallocated buffer with a size big enough
+* to contain the specified samples amount. The filled AVFrame data
+* pointers will point to this buffer.
+*
+* AVFrame extended_data channel pointers are allocated if necessary for
+* planar audio.
+*
+* @param frame       the AVFrame
+*                    frame->nb_samples must be set prior to calling the
+*                    function. This function fills in frame->data,
+*                    frame->extended_data, frame->linesize[0].
+* @param nb_channels channel count
+* @param sample_fmt  sample format
+* @param buf         buffer to use for frame data
+* @param buf_size    size of buffer
+* @param align       plane size sample alignment (0 = default)
+* @return            >=0 on success, negative error code on failure
+* @todo return the size in bytes required to store the samples in
+* case of success, at the next libavutil bump
+*/
+int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
+enum AVSampleFormat sample_fmt, const uint8_t *buf,
+int buf_size, int align);
+/**
+* Flush buffers, should be called when seeking or when switching to a different stream.
+*/
+void avcodec_flush_buffers(AVCodecContext *avctx);
+/**
+* Return codec bits per sample.
+*
+* @param[in] codec_id the codec
+* @return Number of bits per sample or zero if unknown for the given codec.
+*/
+int av_get_bits_per_sample(enum AVCodecID codec_id);
+/**
+* Return the PCM codec associated with a sample format.
+* @param be  endianness, 0 for little, 1 for big,
+*            -1 (or anything else) for native
+* @return  AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
+*/
+enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
+/**
+* Return codec bits per sample.
+* Only return non-zero if the bits per sample is exactly correct, not an
+* approximation.
+*
+* @param[in] codec_id the codec
+* @return Number of bits per sample or zero if unknown for the given codec.
+*/
+int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
+/**
+* Return audio frame duration.
+*
+* @param avctx        codec context
+* @param frame_bytes  size of the frame, or 0 if unknown
+* @return             frame duration, in samples, if known. 0 if not able to
+*                     determine.
+*/
+int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
+typedef struct AVBitStreamFilterContext {
+void *priv_data;
+struct AVBitStreamFilter *filter;
+AVCodecParserContext *parser;
+struct AVBitStreamFilterContext *next;
+} AVBitStreamFilterContext;
+typedef struct AVBitStreamFilter {
+const char *name;
+int priv_data_size;
+int (*filter)(AVBitStreamFilterContext *bsfc,
+AVCodecContext *avctx, const char *args,
+uint8_t **poutbuf, int *poutbuf_size,
+const uint8_t *buf, int buf_size, int keyframe);
+void (*close)(AVBitStreamFilterContext *bsfc);
+struct AVBitStreamFilter *next;
+} AVBitStreamFilter;
+void av_register_bitstream_filter(AVBitStreamFilter *bsf);
+AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
+int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
+AVCodecContext *avctx, const char *args,
+uint8_t **poutbuf, int *poutbuf_size,
+const uint8_t *buf, int buf_size, int keyframe);
+void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
+AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f);
+/* memory */
+/**
+* Reallocate the given block if it is not large enough, otherwise do nothing.
+*
+* @see av_realloc
+*/
+void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size);
+/**
+* Allocate a buffer, reusing the given one if large enough.
+*
+* Contrary to av_fast_realloc the current buffer contents might not be
+* preserved and on error the old buffer is freed, thus no special
+* handling to avoid memleaks is necessary.
+*
+* @param ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer
+* @param size size of the buffer *ptr points to
+* @param min_size minimum size of *ptr buffer after returning, *ptr will be NULL and
+*                 *size 0 if an error occurred.
+*/
+void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size);
+/**
+* Same behaviour av_fast_malloc but the buffer has additional
+* FF_INPUT_BUFFER_PADDING_SIZE at the end which will will always be 0.
+*
+* In addition the whole buffer will initially and after resizes
+* be 0-initialized so that no uninitialized data will ever appear.
+*/
+void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
+/**
+* Same behaviour av_fast_padded_malloc except that buffer will always
+* be 0-initialized after call.
+*/
+void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
+/**
+* Encode extradata length to a buffer. Used by xiph codecs.
+*
+* @param s buffer to write to; must be at least (v/255+1) bytes long
+* @param v size of extradata in bytes
+* @return number of bytes written to the buffer.
+*/
+unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
+#if FF_API_MISSING_SAMPLE
+/**
+* Log a generic warning message about a missing feature. This function is
+* intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
+* only, and would normally not be used by applications.
+* @param[in] avc a pointer to an arbitrary struct of which the first field is
+* a pointer to an AVClass struct
+* @param[in] feature string containing the name of the missing feature
+* @param[in] want_sample indicates if samples are wanted which exhibit this feature.
+* If want_sample is non-zero, additional verbage will be added to the log
+* message which tells the user how to report samples to the development
+* mailing list.
+* @deprecated Use avpriv_report_missing_feature() instead.
+*/
+attribute_deprecated
+void av_log_missing_feature(void *avc, const char *feature, int want_sample);
+/**
+* Log a generic warning message asking for a sample. This function is
+* intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
+* only, and would normally not be used by applications.
+* @param[in] avc a pointer to an arbitrary struct of which the first field is
+* a pointer to an AVClass struct
+* @param[in] msg string containing an optional message, or NULL if no message
+* @deprecated Use avpriv_request_sample() instead.
+*/
+attribute_deprecated
+void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
+#endif /* FF_API_MISSING_SAMPLE */
+/**
+* Register the hardware accelerator hwaccel.
+*/
+void av_register_hwaccel(AVHWAccel *hwaccel);
+/**
+* If hwaccel is NULL, returns the first registered hardware accelerator,
+* if hwaccel is non-NULL, returns the next registered hardware accelerator
+* after hwaccel, or NULL if hwaccel is the last one.
+*/
+AVHWAccel *av_hwaccel_next(AVHWAccel *hwaccel);
+/**
+* Lock operation used by lockmgr
+*/
+enum AVLockOp {
+AV_LOCK_CREATE,  ///< Create a mutex
+AV_LOCK_OBTAIN,  ///< Lock the mutex
+AV_LOCK_RELEASE, ///< Unlock the mutex
+AV_LOCK_DESTROY, ///< Free mutex resources
+};
+/**
+* Register a user provided lock manager supporting the operations
+* specified by AVLockOp. mutex points to a (void *) where the
+* lockmgr should store/get a pointer to a user allocated mutex. It's
+* NULL upon AV_LOCK_CREATE and != NULL for all other ops.
+*
+* @param cb User defined callback. Note: FFmpeg may invoke calls to this
+*           callback during the call to av_lockmgr_register().
+*           Thus, the application must be prepared to handle that.
+*           If cb is set to NULL the lockmgr will be unregistered.
+*           Also note that during unregistration the previously registered
+*           lockmgr callback may also be invoked.
+*/
+int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
+/**
+* Get the type of the given codec.
+*/
+enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
+/**
+* Get the name of a codec.
+* @return  a static string identifying the codec; never NULL
+*/
+const char *avcodec_get_name(enum AVCodecID id);
+/**
+* @return a positive value if s is open (i.e. avcodec_open2() was called on it
+* with no corresponding avcodec_close()), 0 otherwise.
+*/
+int avcodec_is_open(AVCodecContext *s);
+/**
+* @return a non-zero number if codec is an encoder, zero otherwise
+*/
+int av_codec_is_encoder(const AVCodec *codec);
+/**
+* @return a non-zero number if codec is a decoder, zero otherwise
+*/
+int av_codec_is_decoder(const AVCodec *codec);
+/**
+* @return descriptor for given codec ID or NULL if no descriptor exists.
+*/
+const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
+/**
+* Iterate over all codec descriptors known to libavcodec.
+*
+* @param prev previous descriptor. NULL to get the first descriptor.
+*
+* @return next descriptor or NULL after the last descriptor
+*/
+const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
+/**
+* @return codec descriptor with the given name or NULL if no such descriptor
+*         exists.
+*/
+const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
+/**
+* @}
+*/
+#endif /* AVCODEC_AVCODEC_H */

Mercurial > mm7

comparison lib/libavcodec/avcodec.h @ 2134:992d2e6f907d