2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
27 * Libavcodec external API header
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
36 #include "libavutil/channel_layout.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/frame.h"
39 #include "libavutil/log.h"
40 #include "libavutil/pixfmt.h"
41 #include "libavutil/rational.h"
46 * @defgroup libavc libavcodec
47 * Encoding/Decoding Library
51 * @defgroup lavc_decoding Decoding
55 * @defgroup lavc_encoding Encoding
59 * @defgroup lavc_codec Codecs
61 * @defgroup lavc_codec_native Native Codecs
64 * @defgroup lavc_codec_wrappers External library wrappers
67 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
71 * @defgroup lavc_internal Internal
79 * @defgroup lavc_encdec send/receive encoding and decoding API overview
82 * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
83 * avcodec_receive_packet() functions provide an encode/decode API, which
84 * decouples input and output.
86 * The API is very similar for encoding/decoding and audio/video, and works as
88 * - Set up and open the AVCodecContext as usual.
90 * - For decoding, call avcodec_send_packet() to give the decoder raw
91 * compressed data in an AVPacket.
92 * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
93 * containing uncompressed audio or video.
94 * In both cases, it is recommended that AVPackets and AVFrames are
95 * refcounted, or libavcodec might have to copy the input data. (libavformat
96 * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
97 * refcounted AVFrames.)
98 * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
99 * functions and process their output:
100 * - For decoding, call avcodec_receive_frame(). On success, it will return
101 * an AVFrame containing uncompressed audio or video data.
102 * - For encoding, call avcodec_receive_packet(). On success, it will return
103 * an AVPacket with a compressed frame.
104 * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
105 * AVERROR(EAGAIN) return value means that new input data is required to
106 * return new output. In this case, continue with sending input. For each
107 * input frame/packet, the codec will typically return 1 output frame/packet,
108 * but it can also be 0 or more than 1.
110 * At the beginning of decoding or encoding, the codec might accept multiple
111 * input frames/packets without returning a frame, until its internal buffers
112 * are filled. This situation is handled transparently if you follow the steps
115 * In theory, sending input can result in EAGAIN - this should happen only if
116 * not all output was received. You can use this to structure alternative decode
117 * or encode loops other than the one suggested above. For example, you could
118 * try sending new input on each iteration, and try to receive output if that
121 * End of stream situations. These require "flushing" (aka draining) the codec,
122 * as the codec might buffer multiple frames or packets internally for
123 * performance or out of necessity (consider B-frames).
124 * This is handled as follows:
125 * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
126 * or avcodec_send_frame() (encoding) functions. This will enter draining
128 * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
129 * (encoding) in a loop until AVERROR_EOF is returned. The functions will
130 * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
131 * - Before decoding can be resumed again, the codec has to be reset with
132 * avcodec_flush_buffers().
134 * Using the API as outlined above is highly recommended. But it is also
135 * possible to call functions outside of this rigid schema. For example, you can
136 * call avcodec_send_packet() repeatedly without calling
137 * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
138 * until the codec's internal buffer has been filled up (which is typically of
139 * size 1 per output frame, after initial input), and then reject input with
140 * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
141 * read at least some output.
143 * Not all codecs will follow a rigid and predictable dataflow; the only
144 * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
145 * one end implies that a receive/send call on the other end will succeed, or
146 * at least will not fail with AVERROR(EAGAIN). In general, no codec will
147 * permit unlimited buffering of input or output.
149 * This API replaces the following legacy functions:
150 * - avcodec_decode_video2() and avcodec_decode_audio4():
151 * Use avcodec_send_packet() to feed input to the decoder, then use
152 * avcodec_receive_frame() to receive decoded frames after each packet.
153 * Unlike with the old video decoding API, multiple frames might result from
154 * a packet. For audio, splitting the input packet into frames by partially
155 * decoding packets becomes transparent to the API user. You never need to
156 * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
157 * no data was read from the packet).
158 * Additionally, sending a flush/draining packet is required only once.
159 * - avcodec_encode_video2()/avcodec_encode_audio2():
160 * Use avcodec_send_frame() to feed input to the encoder, then use
161 * avcodec_receive_packet() to receive encoded packets.
162 * Providing user-allocated buffers for avcodec_receive_packet() is not
164 * - The new API does not handle subtitles yet.
166 * Mixing new and old function calls on the same AVCodecContext is not allowed,
167 * and will result in undefined behavior.
169 * Some codecs might require using the new API; using the old API will return
170 * an error when calling it. All codecs support the new API.
172 * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
173 * would be an invalid state, which could put the codec user into an endless
174 * loop. The API has no concept of time either: it cannot happen that trying to
175 * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
176 * later accepts the packet (with no other receive/flush API calls involved).
177 * The API is a strict state machine, and the passage of time is not supposed
178 * to influence it. Some timing-dependent behavior might still be deemed
179 * acceptable in certain cases. But it must never result in both send/receive
180 * returning EAGAIN at the same time at any point. It must also absolutely be
181 * avoided that the current state is "unstable" and can "flip-flop" between
182 * the send/receive APIs allowing progress. For example, it's not allowed that
183 * the codec randomly decides that it actually wants to consume a packet now
184 * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
185 * avcodec_send_packet() call.
190 * @defgroup lavc_core Core functions/structures.
193 * Basic definitions, functions for querying libavcodec capabilities,
194 * allocating core structures, etc.
200 * Identify the syntax and semantics of the bitstream.
201 * The principle is roughly:
202 * Two decoders with the same ID can decode the same streams.
203 * Two encoders with the same ID can encode compatible streams.
204 * There may be slight deviations from the principle due to implementation
207 * If you add a codec ID to this list, add it so that
208 * 1. no value of an existing codec ID changes (that would break ABI),
209 * 2. it is as close as possible to similar codecs
211 * After adding new codec IDs, do not forget to add an entry to the codec
212 * descriptor list and bump libavcodec minor version.
218 AV_CODEC_ID_MPEG1VIDEO,
219 AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
230 AV_CODEC_ID_RAWVIDEO,
231 AV_CODEC_ID_MSMPEG4V1,
232 AV_CODEC_ID_MSMPEG4V2,
233 AV_CODEC_ID_MSMPEG4V3,
256 AV_CODEC_ID_INTERPLAY_VIDEO,
263 AV_CODEC_ID_MSVIDEO1,
268 AV_CODEC_ID_TRUEMOTION1,
269 AV_CODEC_ID_VMDVIDEO,
294 AV_CODEC_ID_TRUEMOTION2,
300 AV_CODEC_ID_SMACKVIDEO,
305 AV_CODEC_ID_JPEG2000,
311 AV_CODEC_ID_DSICINVIDEO,
312 AV_CODEC_ID_TIERTEXSEQVIDEO,
320 AV_CODEC_ID_BETHSOFTVID,
332 AV_CODEC_ID_ESCAPE124,
336 AV_CODEC_ID_MOTIONPIXELS,
348 AV_CODEC_ID_FLASHSV2,
349 AV_CODEC_ID_CDGRAPHICS,
352 AV_CODEC_ID_BINKVIDEO,
353 AV_CODEC_ID_IFF_ILBM,
354 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
360 AV_CODEC_ID_A64_MULTI,
361 AV_CODEC_ID_A64_MULTI5,
364 AV_CODEC_ID_LAGARITH,
368 AV_CODEC_ID_WMV3IMAGE,
369 AV_CODEC_ID_VC1IMAGE,
371 AV_CODEC_ID_BMV_VIDEO,
378 AV_CODEC_ID_ZEROCODEC,
387 AV_CODEC_ID_ESCAPE130,
390 AV_CODEC_ID_HNM4_VIDEO,
392 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
394 AV_CODEC_ID_ALIAS_PIX,
395 AV_CODEC_ID_BRENDER_PIX,
396 AV_CODEC_ID_PAF_VIDEO,
409 AV_CODEC_ID_SCREENPRESSO,
412 AV_CODEC_ID_Y41P = 0x8000,
417 AV_CODEC_ID_TARGA_Y216,
429 AV_CODEC_ID_TRUEMOTION2RT,
431 AV_CODEC_ID_MAGICYUV,
432 AV_CODEC_ID_SHEERVIDEO,
439 AV_CODEC_ID_CLEARVIDEO,
442 AV_CODEC_ID_BITPACKED,
449 /* various PCM "codecs" */
450 AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
451 AV_CODEC_ID_PCM_S16LE = 0x10000,
452 AV_CODEC_ID_PCM_S16BE,
453 AV_CODEC_ID_PCM_U16LE,
454 AV_CODEC_ID_PCM_U16BE,
457 AV_CODEC_ID_PCM_MULAW,
458 AV_CODEC_ID_PCM_ALAW,
459 AV_CODEC_ID_PCM_S32LE,
460 AV_CODEC_ID_PCM_S32BE,
461 AV_CODEC_ID_PCM_U32LE,
462 AV_CODEC_ID_PCM_U32BE,
463 AV_CODEC_ID_PCM_S24LE,
464 AV_CODEC_ID_PCM_S24BE,
465 AV_CODEC_ID_PCM_U24LE,
466 AV_CODEC_ID_PCM_U24BE,
467 AV_CODEC_ID_PCM_S24DAUD,
468 AV_CODEC_ID_PCM_ZORK,
469 AV_CODEC_ID_PCM_S16LE_PLANAR,
471 AV_CODEC_ID_PCM_F32BE,
472 AV_CODEC_ID_PCM_F32LE,
473 AV_CODEC_ID_PCM_F64BE,
474 AV_CODEC_ID_PCM_F64LE,
475 AV_CODEC_ID_PCM_BLURAY,
478 AV_CODEC_ID_PCM_S8_PLANAR,
479 AV_CODEC_ID_PCM_S24LE_PLANAR,
480 AV_CODEC_ID_PCM_S32LE_PLANAR,
481 AV_CODEC_ID_PCM_S16BE_PLANAR,
483 AV_CODEC_ID_PCM_S64LE = 0x10800,
484 AV_CODEC_ID_PCM_S64BE,
485 AV_CODEC_ID_PCM_F16LE,
486 AV_CODEC_ID_PCM_F24LE,
488 /* various ADPCM codecs */
489 AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
490 AV_CODEC_ID_ADPCM_IMA_WAV,
491 AV_CODEC_ID_ADPCM_IMA_DK3,
492 AV_CODEC_ID_ADPCM_IMA_DK4,
493 AV_CODEC_ID_ADPCM_IMA_WS,
494 AV_CODEC_ID_ADPCM_IMA_SMJPEG,
495 AV_CODEC_ID_ADPCM_MS,
496 AV_CODEC_ID_ADPCM_4XM,
497 AV_CODEC_ID_ADPCM_XA,
498 AV_CODEC_ID_ADPCM_ADX,
499 AV_CODEC_ID_ADPCM_EA,
500 AV_CODEC_ID_ADPCM_G726,
501 AV_CODEC_ID_ADPCM_CT,
502 AV_CODEC_ID_ADPCM_SWF,
503 AV_CODEC_ID_ADPCM_YAMAHA,
504 AV_CODEC_ID_ADPCM_SBPRO_4,
505 AV_CODEC_ID_ADPCM_SBPRO_3,
506 AV_CODEC_ID_ADPCM_SBPRO_2,
507 AV_CODEC_ID_ADPCM_THP,
508 AV_CODEC_ID_ADPCM_IMA_AMV,
509 AV_CODEC_ID_ADPCM_EA_R1,
510 AV_CODEC_ID_ADPCM_EA_R3,
511 AV_CODEC_ID_ADPCM_EA_R2,
512 AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
513 AV_CODEC_ID_ADPCM_IMA_EA_EACS,
514 AV_CODEC_ID_ADPCM_EA_XAS,
515 AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
516 AV_CODEC_ID_ADPCM_IMA_ISS,
517 AV_CODEC_ID_ADPCM_G722,
518 AV_CODEC_ID_ADPCM_IMA_APC,
519 AV_CODEC_ID_ADPCM_VIMA,
521 AV_CODEC_ID_ADPCM_AFC = 0x11800,
522 AV_CODEC_ID_ADPCM_IMA_OKI,
523 AV_CODEC_ID_ADPCM_DTK,
524 AV_CODEC_ID_ADPCM_IMA_RAD,
525 AV_CODEC_ID_ADPCM_G726LE,
526 AV_CODEC_ID_ADPCM_THP_LE,
527 AV_CODEC_ID_ADPCM_PSX,
528 AV_CODEC_ID_ADPCM_AICA,
529 AV_CODEC_ID_ADPCM_IMA_DAT4,
530 AV_CODEC_ID_ADPCM_MTAF,
533 AV_CODEC_ID_AMR_NB = 0x12000,
536 /* RealAudio codecs*/
537 AV_CODEC_ID_RA_144 = 0x13000,
540 /* various DPCM codecs */
541 AV_CODEC_ID_ROQ_DPCM = 0x14000,
542 AV_CODEC_ID_INTERPLAY_DPCM,
543 AV_CODEC_ID_XAN_DPCM,
544 AV_CODEC_ID_SOL_DPCM,
546 AV_CODEC_ID_SDX2_DPCM = 0x14800,
547 AV_CODEC_ID_GREMLIN_DPCM,
550 AV_CODEC_ID_MP2 = 0x15000,
551 AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
561 AV_CODEC_ID_VMDAUDIO,
567 AV_CODEC_ID_WESTWOOD_SND1,
568 AV_CODEC_ID_GSM, ///< as in Berlin toast format
571 AV_CODEC_ID_TRUESPEECH,
573 AV_CODEC_ID_SMACKAUDIO,
576 AV_CODEC_ID_DSICINAUDIO,
578 AV_CODEC_ID_MUSEPACK7,
580 AV_CODEC_ID_GSM_MS, /* as found in WAV */
583 AV_CODEC_ID_NELLYMOSER,
584 AV_CODEC_ID_MUSEPACK8,
586 AV_CODEC_ID_WMAVOICE,
588 AV_CODEC_ID_WMALOSSLESS,
597 AV_CODEC_ID_BINKAUDIO_RDFT,
598 AV_CODEC_ID_BINKAUDIO_DCT,
599 AV_CODEC_ID_AAC_LATM,
604 AV_CODEC_ID_8SVX_EXP,
605 AV_CODEC_ID_8SVX_FIB,
606 AV_CODEC_ID_BMV_AUDIO,
611 AV_CODEC_ID_COMFORT_NOISE,
613 AV_CODEC_ID_METASOUND,
614 AV_CODEC_ID_PAF_AUDIO,
618 AV_CODEC_ID_FFWAVESYNTH = 0x15800,
620 AV_CODEC_ID_SONIC_LS,
623 AV_CODEC_ID_DSD_LSBF,
624 AV_CODEC_ID_DSD_MSBF,
625 AV_CODEC_ID_DSD_LSBF_PLANAR,
626 AV_CODEC_ID_DSD_MSBF_PLANAR,
628 AV_CODEC_ID_INTERPLAY_ACM,
632 AV_CODEC_ID_ATRAC3AL,
633 AV_CODEC_ID_ATRAC3PAL,
637 /* subtitle codecs */
638 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
639 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
640 AV_CODEC_ID_DVB_SUBTITLE,
641 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
644 AV_CODEC_ID_MOV_TEXT,
645 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
646 AV_CODEC_ID_DVB_TELETEXT,
649 AV_CODEC_ID_MICRODVD = 0x17800,
653 AV_CODEC_ID_REALTEXT,
655 AV_CODEC_ID_SUBVIEWER1,
656 AV_CODEC_ID_SUBVIEWER,
663 AV_CODEC_ID_HDMV_TEXT_SUBTITLE,
665 /* other specific kind of codecs (generally used for attachments) */
666 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
667 AV_CODEC_ID_TTF = 0x18000,
669 AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
670 AV_CODEC_ID_BINTEXT = 0x18800,
674 AV_CODEC_ID_SMPTE_KLV,
676 AV_CODEC_ID_TIMED_ID3,
677 AV_CODEC_ID_BIN_DATA,
680 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
682 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
683 * stream (only used by libavformat) */
684 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
685 * stream (only used by libavformat) */
686 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
687 AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
691 * This struct describes the properties of a single codec described by an
693 * @see avcodec_descriptor_get()
695 typedef struct AVCodecDescriptor {
697 enum AVMediaType type;
699 * Name of the codec described by this descriptor. It is non-empty and
700 * unique for each codec descriptor. It should contain alphanumeric
701 * characters and '_' only.
705 * A more descriptive name for this codec. May be NULL.
707 const char *long_name;
709 * Codec properties, a combination of AV_CODEC_PROP_* flags.
713 * MIME type(s) associated with the codec.
714 * May be NULL; if not, a NULL-terminated array of MIME types.
715 * The first item is always non-NULL and is the preferred MIME type.
717 const char *const *mime_types;
719 * If non-NULL, an array of profiles recognized for this codec.
720 * Terminated with FF_PROFILE_UNKNOWN.
722 const struct AVProfile *profiles;
726 * Codec uses only intra compression.
727 * Video and audio codecs only.
729 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
731 * Codec supports lossy compression. Audio and video codecs only.
732 * @note a codec may support both lossy and lossless
735 #define AV_CODEC_PROP_LOSSY (1 << 1)
737 * Codec supports lossless compression. Audio and video codecs only.
739 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
741 * Codec supports frame reordering. That is, the coded order (the order in which
742 * the encoded packets are output by the encoders / stored / input to the
743 * decoders) may be different from the presentation order of the corresponding
746 * For codecs that do not have this property set, PTS and DTS should always be
749 #define AV_CODEC_PROP_REORDER (1 << 3)
751 * Subtitle codec is bitmap based
752 * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
754 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
756 * Subtitle codec is text based.
757 * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
759 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
762 * @ingroup lavc_decoding
763 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
764 * This is mainly needed because some optimized bitstream readers read
765 * 32 or 64 bit at once and could read over the end.<br>
766 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
767 * MPEG bitstreams could cause overread and segfault.
769 #define AV_INPUT_BUFFER_PADDING_SIZE 32
772 * @ingroup lavc_encoding
773 * minimum encoding buffer size
774 * Used to avoid some checks during header writing.
776 #define AV_INPUT_BUFFER_MIN_SIZE 16384
779 * @ingroup lavc_decoding
782 /* We leave some space between them for extensions (drop some
783 * keyframes for intra-only or drop just some bidir frames). */
784 AVDISCARD_NONE =-16, ///< discard nothing
785 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
786 AVDISCARD_NONREF = 8, ///< discard all non reference
787 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
788 AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
789 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
790 AVDISCARD_ALL = 48, ///< discard all
793 enum AVAudioServiceType {
794 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
795 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
796 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
797 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
798 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
799 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
800 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
801 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
802 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
803 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
807 * @ingroup lavc_encoding
809 typedef struct RcOverride{
812 int qscale; // If this is 0 then quality_factor will be used instead.
813 float quality_factor;
817 These flags can be passed in AVCodecContext.flags before initialization.
818 Note: Not everything is supported yet.
822 * Allow decoders to produce frames with data planes that are not aligned
823 * to CPU requirements (e.g. due to cropping).
825 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
829 #define AV_CODEC_FLAG_QSCALE (1 << 1)
831 * 4 MV per MB allowed / advanced prediction for H.263.
833 #define AV_CODEC_FLAG_4MV (1 << 2)
835 * Output even those frames that might be corrupted.
837 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
841 #define AV_CODEC_FLAG_QPEL (1 << 4)
843 * Use internal 2pass ratecontrol in first pass mode.
845 #define AV_CODEC_FLAG_PASS1 (1 << 9)
847 * Use internal 2pass ratecontrol in second pass mode.
849 #define AV_CODEC_FLAG_PASS2 (1 << 10)
853 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
855 * Only decode/encode grayscale.
857 #define AV_CODEC_FLAG_GRAY (1 << 13)
859 * error[?] variables will be set during encoding.
861 #define AV_CODEC_FLAG_PSNR (1 << 15)
863 * Input bitstream might be truncated at a random location
864 * instead of only at frame boundaries.
866 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
868 * Use interlaced DCT.
870 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
874 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
876 * Place global headers in extradata instead of every keyframe.
878 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
880 * Use only bitexact stuff (except (I)DCT).
882 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
883 /* Fx : Flag for H.263+ extra options */
885 * H.263 advanced intra coding / MPEG-4 AC prediction
887 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
889 * interlaced motion estimation
891 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
892 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
895 * Allow non spec compliant speedup tricks.
897 #define AV_CODEC_FLAG2_FAST (1 << 0)
899 * Skip bitstream encoding.
901 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
903 * Place global headers at every keyframe instead of in extradata.
905 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
908 * timecode is in drop frame format. DEPRECATED!!!!
910 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
913 * Input bitstream might be truncated at a packet boundaries
914 * instead of only at frame boundaries.
916 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
918 * Discard cropping information from SPS.
920 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
923 * Show all frames before the first keyframe
925 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
927 * Export motion vectors through frame side data
929 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
931 * Do not skip samples and export skip information as frame side data
933 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
935 * Do not reset ASS ReadOrder field on flush (subtitles decoding)
937 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
939 /* Unsupported options :
940 * Syntax Arithmetic coding (SAC)
941 * Reference Picture Selection
942 * Independent Segment Decoding */
944 /* codec capabilities */
947 * Decoder can use draw_horiz_band callback.
949 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
951 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
952 * If not set, it might not use get_buffer() at all or use operations that
953 * assume the buffer was allocated by avcodec_default_get_buffer.
955 #define AV_CODEC_CAP_DR1 (1 << 1)
956 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
958 * Encoder or decoder requires flushing with NULL input at the end in order to
959 * give the complete and correct output.
961 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
962 * with NULL data. The user can still send NULL data to the public encode
963 * or decode function, but libavcodec will not pass it along to the codec
964 * unless this flag is set.
967 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
968 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
972 * The encoder needs to be fed with NULL data at the end of encoding until the
973 * encoder no longer returns data.
975 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
976 * flag also means that the encoder must set the pts and duration for
977 * each output packet. If this flag is not set, the pts and duration will
978 * be determined by libavcodec from the input frame.
980 #define AV_CODEC_CAP_DELAY (1 << 5)
982 * Codec can be fed a final frame with a smaller size.
983 * This can be used to prevent truncation of the last audio samples.
985 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
988 * Codec can output multiple frames per AVPacket
989 * Normally demuxers return one frame at a time, demuxers which do not do
990 * are connected to a parser to split what they return into proper frames.
991 * This flag is reserved to the very rare category of codecs which have a
992 * bitstream that cannot be split into frames without timeconsuming
993 * operations like full decoding. Demuxers carrying such bitstreams thus
994 * may return multiple frames in a packet. This has many disadvantages like
995 * prohibiting stream copy in many cases thus it should only be considered
998 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1000 * Codec is experimental and is thus avoided in favor of non experimental
1003 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1005 * Codec should fill in channel configuration and samplerate instead of container
1007 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1009 * Codec supports frame-level multithreading.
1011 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1013 * Codec supports slice-based (or partition-based) multithreading.
1015 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1017 * Codec supports changed parameters at any point.
1019 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1021 * Codec supports avctx->thread_count == 0 (auto).
1023 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1025 * Audio encoder supports receiving a different number of samples in each call.
1027 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1029 * Decoder is not a preferred choice for probing.
1030 * This indicates that the decoder is not a good choice for probing.
1031 * It could for example be an expensive to spin up hardware decoder,
1032 * or it could simply not provide a lot of useful information about
1034 * A decoder marked with this flag should only be used as last resort
1035 * choice for probing.
1037 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1039 * Codec is intra only.
1041 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1043 * Codec is lossless.
1045 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1049 * This specifies the area which should be displayed.
1050 * Note there may be multiple such areas for one frame.
1052 typedef struct AVPanScan {
1055 * - encoding: Set by user.
1056 * - decoding: Set by libavcodec.
1061 * width and height in 1/16 pel
1062 * - encoding: Set by user.
1063 * - decoding: Set by libavcodec.
1069 * position of the top left corner in 1/16 pel for up to 3 fields/frames
1070 * - encoding: Set by user.
1071 * - decoding: Set by libavcodec.
1073 int16_t position[3][2];
1077 * This structure describes the bitrate properties of an encoded bitstream. It
1078 * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1079 * parameters for H.264/HEVC.
1081 typedef struct AVCPBProperties {
1083 * Maximum bitrate of the stream, in bits per second.
1084 * Zero if unknown or unspecified.
1088 * Minimum bitrate of the stream, in bits per second.
1089 * Zero if unknown or unspecified.
1093 * Average bitrate of the stream, in bits per second.
1094 * Zero if unknown or unspecified.
1099 * The size of the buffer to which the ratecontrol is applied, in bits.
1100 * Zero if unknown or unspecified.
1105 * The delay between the time the packet this structure is associated with
1106 * is received and the time when it should be decoded, in periods of a 27MHz
1109 * UINT64_MAX when unknown or unspecified.
1115 * The decoder will keep a reference to the frame and may reuse it later.
1117 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1120 * @defgroup lavc_packet AVPacket
1122 * Types and functions for working with AVPacket.
1125 enum AVPacketSideDataType {
1127 * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1128 * bytes worth of palette. This side data signals that a new palette is
1131 AV_PKT_DATA_PALETTE,
1134 * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1135 * that the extradata buffer was changed and the receiving side should
1136 * act upon it appropriately. The new extradata is embedded in the side
1137 * data buffer and should be immediately used for processing the current
1140 AV_PKT_DATA_NEW_EXTRADATA,
1143 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1146 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1147 * s32le channel_count
1148 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1149 * u64le channel_layout
1150 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1152 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1157 AV_PKT_DATA_PARAM_CHANGE,
1160 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1161 * structures with info about macroblocks relevant to splitting the
1162 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1163 * That is, it does not necessarily contain info about all macroblocks,
1164 * as long as the distance between macroblocks in the info is smaller
1165 * than the target payload size.
1166 * Each MB info structure is 12 bytes, and is laid out as follows:
1168 * u32le bit offset from the start of the packet
1169 * u8 current quantizer at the start of the macroblock
1171 * u16le macroblock address within the GOB
1172 * u8 horizontal MV predictor
1173 * u8 vertical MV predictor
1174 * u8 horizontal MV predictor for block number 3
1175 * u8 vertical MV predictor for block number 3
1178 AV_PKT_DATA_H263_MB_INFO,
1181 * This side data should be associated with an audio stream and contains
1182 * ReplayGain information in form of the AVReplayGain struct.
1184 AV_PKT_DATA_REPLAYGAIN,
1187 * This side data contains a 3x3 transformation matrix describing an affine
1188 * transformation that needs to be applied to the decoded video frames for
1189 * correct presentation.
1191 * See libavutil/display.h for a detailed description of the data.
1193 AV_PKT_DATA_DISPLAYMATRIX,
1196 * This side data should be associated with a video stream and contains
1197 * Stereoscopic 3D information in form of the AVStereo3D struct.
1199 AV_PKT_DATA_STEREO3D,
1202 * This side data should be associated with an audio stream and corresponds
1203 * to enum AVAudioServiceType.
1205 AV_PKT_DATA_AUDIO_SERVICE_TYPE,
1208 * This side data contains quality related information from the encoder.
1210 * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1214 * u64le[error count] sum of squared differences between encoder in and output
1217 AV_PKT_DATA_QUALITY_STATS,
1220 * This side data contains an integer value representing the stream index
1221 * of a "fallback" track. A fallback track indicates an alternate
1222 * track to use when the current track can not be decoded for some reason.
1223 * e.g. no decoder available for codec.
1225 AV_PKT_DATA_FALLBACK_TRACK,
1228 * This side data corresponds to the AVCPBProperties struct.
1230 AV_PKT_DATA_CPB_PROPERTIES,
1233 * Recommmends skipping the specified number of samples
1235 * u32le number of samples to skip from start of this packet
1236 * u32le number of samples to skip from end of this packet
1237 * u8 reason for start skip
1238 * u8 reason for end skip (0=padding silence, 1=convergence)
1241 AV_PKT_DATA_SKIP_SAMPLES,
1244 * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1245 * the packet may contain "dual mono" audio specific to Japanese DTV
1246 * and if it is true, recommends only the selected channel to be used.
1248 * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1251 AV_PKT_DATA_JP_DUALMONO,
1254 * A list of zero terminated key/value strings. There is no end marker for
1255 * the list, so it is required to rely on the side data size to stop.
1257 AV_PKT_DATA_STRINGS_METADATA,
1260 * Subtitle event position
1268 AV_PKT_DATA_SUBTITLE_POSITION,
1271 * Data found in BlockAdditional element of matroska container. There is
1272 * no end marker for the data, so it is required to rely on the side data
1273 * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1276 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1279 * The optional first identifier line of a WebVTT cue.
1281 AV_PKT_DATA_WEBVTT_IDENTIFIER,
1284 * The optional settings (rendering instructions) that immediately
1285 * follow the timestamp specifier of a WebVTT cue.
1287 AV_PKT_DATA_WEBVTT_SETTINGS,
1290 * A list of zero terminated key/value strings. There is no end marker for
1291 * the list, so it is required to rely on the side data size to stop. This
1292 * side data includes updated metadata which appeared in the stream.
1294 AV_PKT_DATA_METADATA_UPDATE,
1297 * MPEGTS stream ID, this is required to pass the stream ID
1298 * information from the demuxer to the corresponding muxer.
1300 AV_PKT_DATA_MPEGTS_STREAM_ID,
1303 * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1304 * should be associated with a video stream and contains data in the form
1305 * of the AVMasteringDisplayMetadata struct.
1307 AV_PKT_DATA_MASTERING_DISPLAY_METADATA,
1310 * This side data should be associated with a video stream and corresponds
1311 * to the AVSphericalMapping structure.
1313 AV_PKT_DATA_SPHERICAL,
1316 * Content light level (based on CTA-861.3). This metadata should be
1317 * associated with a video stream and contains data in the form of the
1318 * AVContentLightMetadata struct.
1320 AV_PKT_DATA_CONTENT_LIGHT_LEVEL,
1323 * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1324 * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1325 * The number of bytes of CC data is AVPacketSideData.size.
1330 * The number of side data types.
1331 * This is not part of the public API/ABI in the sense that it may
1332 * change when new side data types are added.
1333 * This must stay the last enum value.
1334 * If its value becomes huge, some code using it
1335 * needs to be updated as it assumes it to be smaller than other limits.
1340 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1342 typedef struct AVPacketSideData {
1345 enum AVPacketSideDataType type;
1349 * This structure stores compressed data. It is typically exported by demuxers
1350 * and then passed as input to decoders, or received as output from encoders and
1351 * then passed to muxers.
1353 * For video, it should typically contain one compressed frame. For audio it may
1354 * contain several compressed frames. Encoders are allowed to output empty
1355 * packets, with no compressed data, containing only side data
1356 * (e.g. to update some stream parameters at the end of encoding).
1358 * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1359 * ABI. Thus it may be allocated on stack and no new fields can be added to it
1360 * without libavcodec and libavformat major bump.
1362 * The semantics of data ownership depends on the buf field.
1363 * If it is set, the packet data is dynamically allocated and is
1364 * valid indefinitely until a call to av_packet_unref() reduces the
1365 * reference count to 0.
1367 * If the buf field is not set av_packet_ref() would make a copy instead
1368 * of increasing the reference count.
1370 * The side data is always allocated with av_malloc(), copied by
1371 * av_packet_ref() and freed by av_packet_unref().
1373 * @see av_packet_ref
1374 * @see av_packet_unref
1376 typedef struct AVPacket {
1378 * A reference to the reference-counted buffer where the packet data is
1380 * May be NULL, then the packet data is not reference-counted.
1384 * Presentation timestamp in AVStream->time_base units; the time at which
1385 * the decompressed packet will be presented to the user.
1386 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1387 * pts MUST be larger or equal to dts as presentation cannot happen before
1388 * decompression, unless one wants to view hex dumps. Some formats misuse
1389 * the terms dts and pts/cts to mean something different. Such timestamps
1390 * must be converted to true pts/dts before they are stored in AVPacket.
1394 * Decompression timestamp in AVStream->time_base units; the time at which
1395 * the packet is decompressed.
1396 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1403 * A combination of AV_PKT_FLAG values
1407 * Additional packet data that can be provided by the container.
1408 * Packet can contain several types of side information.
1410 AVPacketSideData *side_data;
1411 int side_data_elems;
1414 * Duration of this packet in AVStream->time_base units, 0 if unknown.
1415 * Equals next_pts - this_pts in presentation order.
1419 int64_t pos; ///< byte position in stream, -1 if unknown
1421 #if FF_API_CONVERGENCE_DURATION
1423 * @deprecated Same as the duration field, but as int64_t. This was required
1424 * for Matroska subtitles, whose duration values could overflow when the
1425 * duration field was still an int.
1427 attribute_deprecated
1428 int64_t convergence_duration;
1431 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1432 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1434 * Flag is used to discard packets which are required to maintain valid
1435 * decoder state but are not required for output and should be dropped
1438 #define AV_PKT_FLAG_DISCARD 0x0004
1440 * The packet comes from a trusted source.
1442 * Otherwise-unsafe constructs such as arbitrary pointers to data
1443 * outside the packet may be followed.
1445 #define AV_PKT_FLAG_TRUSTED 0x0008
1447 enum AVSideDataParamChangeFlags {
1448 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1449 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1450 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1451 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1457 struct AVCodecInternal;
1461 AV_FIELD_PROGRESSIVE,
1462 AV_FIELD_TT, //< Top coded_first, top displayed first
1463 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1464 AV_FIELD_TB, //< Top coded first, bottom displayed first
1465 AV_FIELD_BT, //< Bottom coded first, top displayed first
1469 * main external API structure.
1470 * New fields can be added to the end with minor version bumps.
1471 * Removal, reordering and changes to existing fields require a major
1473 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1475 * The name string for AVOptions options matches the associated command line
1476 * parameter name and can be found in libavcodec/options_table.h
1477 * The AVOption/command line parameter names differ in some cases from the C
1478 * structure field names for historic reasons or brevity.
1479 * sizeof(AVCodecContext) must not be used outside libav*.
1481 typedef struct AVCodecContext {
1483 * information on struct for av_log
1484 * - set by avcodec_alloc_context3
1486 const AVClass *av_class;
1487 int log_level_offset;
1489 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1490 const struct AVCodec *codec;
1491 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1494 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1495 * This is used to work around some encoder bugs.
1496 * A demuxer should set this to what is stored in the field used to identify the codec.
1497 * If there are multiple such fields in a container then the demuxer should choose the one
1498 * which maximizes the information about the used codec.
1499 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1500 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1501 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1503 * - encoding: Set by user, if not then the default based on codec_id will be used.
1504 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1506 unsigned int codec_tag;
1511 * Private context used for internal data.
1513 * Unlike priv_data, this is not codec-specific. It is used in general
1514 * libavcodec functions.
1516 struct AVCodecInternal *internal;
1519 * Private data of the user, can be used to carry app specific stuff.
1520 * - encoding: Set by user.
1521 * - decoding: Set by user.
1526 * the average bitrate
1527 * - encoding: Set by user; unused for constant quantizer encoding.
1528 * - decoding: Set by user, may be overwritten by libavcodec
1529 * if this info is available in the stream
1534 * number of bits the bitstream is allowed to diverge from the reference.
1535 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1536 * - encoding: Set by user; unused for constant quantizer encoding.
1537 * - decoding: unused
1539 int bit_rate_tolerance;
1542 * Global quality for codecs which cannot change it per frame.
1543 * This should be proportional to MPEG-1/2/4 qscale.
1544 * - encoding: Set by user.
1545 * - decoding: unused
1550 * - encoding: Set by user.
1551 * - decoding: unused
1553 int compression_level;
1554 #define FF_COMPRESSION_DEFAULT -1
1558 * - encoding: Set by user.
1559 * - decoding: Set by user.
1565 * - encoding: Set by user.
1566 * - decoding: Set by user.
1571 * some codecs need / can use extradata like Huffman tables.
1572 * MJPEG: Huffman tables
1573 * rv10: additional flags
1574 * MPEG-4: global headers (they can be in the bitstream or here)
1575 * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1576 * than extradata_size to avoid problems if it is read with the bitstream reader.
1577 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1578 * - encoding: Set/allocated/freed by libavcodec.
1579 * - decoding: Set/allocated/freed by user.
1585 * This is the fundamental unit of time (in seconds) in terms
1586 * of which frame timestamps are represented. For fixed-fps content,
1587 * timebase should be 1/framerate and timestamp increments should be
1589 * This often, but not always is the inverse of the frame rate or field rate
1590 * for video. 1/time_base is not the average frame rate if the frame rate is not
1593 * Like containers, elementary streams also can store timestamps, 1/time_base
1594 * is the unit in which these timestamps are specified.
1595 * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1596 * vop_time_increment_resolution and fixed_vop_rate
1597 * (fixed_vop_rate == 0 implies that it is different from the framerate)
1599 * - encoding: MUST be set by user.
1600 * - decoding: the use of this field for decoding is deprecated.
1601 * Use framerate instead.
1603 AVRational time_base;
1606 * For some codecs, the time base is closer to the field rate than the frame rate.
1607 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1608 * if no telecine is used ...
1610 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1612 int ticks_per_frame;
1617 * Encoding: Number of frames delay there will be from the encoder input to
1618 * the decoder output. (we assume the decoder matches the spec)
1619 * Decoding: Number of frames delay in addition to what a standard decoder
1620 * as specified in the spec would produce.
1623 * Number of frames the decoded output will be delayed relative to the
1627 * For encoding, this field is unused (see initial_padding).
1629 * For decoding, this is the number of samples the decoder needs to
1630 * output before the decoder's output is valid. When seeking, you should
1631 * start decoding this many samples prior to your desired seek point.
1633 * - encoding: Set by libavcodec.
1634 * - decoding: Set by libavcodec.
1641 * picture width / height.
1643 * @note Those fields may not match the values of the last
1644 * AVFrame output by avcodec_decode_video2 due frame
1647 * - encoding: MUST be set by user.
1648 * - decoding: May be set by the user before opening the decoder if known e.g.
1649 * from the container. Some decoders will require the dimensions
1650 * to be set by the caller. During decoding, the decoder may
1651 * overwrite those values as required while parsing the data.
1656 * Bitstream width / height, may be different from width/height e.g. when
1657 * the decoded frame is cropped before being output or lowres is enabled.
1659 * @note Those field may not match the value of the last
1660 * AVFrame output by avcodec_receive_frame() due frame
1663 * - encoding: unused
1664 * - decoding: May be set by the user before opening the decoder if known
1665 * e.g. from the container. During decoding, the decoder may
1666 * overwrite those values as required while parsing the data.
1668 int coded_width, coded_height;
1671 * the number of pictures in a group of pictures, or 0 for intra_only
1672 * - encoding: Set by user.
1673 * - decoding: unused
1678 * Pixel format, see AV_PIX_FMT_xxx.
1679 * May be set by the demuxer if known from headers.
1680 * May be overridden by the decoder if it knows better.
1682 * @note This field may not match the value of the last
1683 * AVFrame output by avcodec_receive_frame() due frame
1686 * - encoding: Set by user.
1687 * - decoding: Set by user if known, overridden by libavcodec while
1690 enum AVPixelFormat pix_fmt;
1693 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1694 * decoder to draw a horizontal band. It improves cache usage. Not
1695 * all codecs can do that. You must check the codec capabilities
1697 * When multithreading is used, it may be called from multiple threads
1698 * at the same time; threads might draw different parts of the same AVFrame,
1699 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1701 * The function is also used by hardware acceleration APIs.
1702 * It is called at least once during frame decoding to pass
1703 * the data needed for hardware render.
1704 * In that mode instead of pixel data, AVFrame points to
1705 * a structure specific to the acceleration API. The application
1706 * reads the structure and can change some fields to indicate progress
1708 * - encoding: unused
1709 * - decoding: Set by user.
1710 * @param height the height of the slice
1711 * @param y the y position of the slice
1712 * @param type 1->top field, 2->bottom field, 3->frame
1713 * @param offset offset into the AVFrame.data from which the slice should be read
1715 void (*draw_horiz_band)(struct AVCodecContext *s,
1716 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1717 int y, int type, int height);
1720 * callback to negotiate the pixelFormat
1721 * @param fmt is the list of formats which are supported by the codec,
1722 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1723 * The first is always the native one.
1724 * @note The callback may be called again immediately if initialization for
1725 * the selected (hardware-accelerated) pixel format failed.
1726 * @warning Behavior is undefined if the callback returns a value not
1727 * in the fmt list of formats.
1728 * @return the chosen format
1729 * - encoding: unused
1730 * - decoding: Set by user, if not set the native format will be chosen.
1732 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1735 * maximum number of B-frames between non-B-frames
1736 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1737 * - encoding: Set by user.
1738 * - decoding: unused
1743 * qscale factor between IP and B-frames
1744 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1745 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1746 * - encoding: Set by user.
1747 * - decoding: unused
1749 float b_quant_factor;
1751 #if FF_API_PRIVATE_OPT
1752 /** @deprecated use encoder private options instead */
1753 attribute_deprecated
1754 int b_frame_strategy;
1758 * qscale offset between IP and B-frames
1759 * - encoding: Set by user.
1760 * - decoding: unused
1762 float b_quant_offset;
1765 * Size of the frame reordering buffer in the decoder.
1766 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1767 * - encoding: Set by libavcodec.
1768 * - decoding: Set by libavcodec.
1772 #if FF_API_PRIVATE_OPT
1773 /** @deprecated use encoder private options instead */
1774 attribute_deprecated
1779 * qscale factor between P- and I-frames
1780 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1781 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1782 * - encoding: Set by user.
1783 * - decoding: unused
1785 float i_quant_factor;
1788 * qscale offset between P and I-frames
1789 * - encoding: Set by user.
1790 * - decoding: unused
1792 float i_quant_offset;
1795 * luminance masking (0-> disabled)
1796 * - encoding: Set by user.
1797 * - decoding: unused
1802 * temporary complexity masking (0-> disabled)
1803 * - encoding: Set by user.
1804 * - decoding: unused
1806 float temporal_cplx_masking;
1809 * spatial complexity masking (0-> disabled)
1810 * - encoding: Set by user.
1811 * - decoding: unused
1813 float spatial_cplx_masking;
1816 * p block masking (0-> disabled)
1817 * - encoding: Set by user.
1818 * - decoding: unused
1823 * darkness masking (0-> disabled)
1824 * - encoding: Set by user.
1825 * - decoding: unused
1831 * - encoding: Set by libavcodec.
1832 * - decoding: Set by user (or 0).
1836 #if FF_API_PRIVATE_OPT
1837 /** @deprecated use encoder private options instead */
1838 attribute_deprecated
1839 int prediction_method;
1840 #define FF_PRED_LEFT 0
1841 #define FF_PRED_PLANE 1
1842 #define FF_PRED_MEDIAN 2
1846 * slice offsets in the frame in bytes
1847 * - encoding: Set/allocated by libavcodec.
1848 * - decoding: Set/allocated by user (or NULL).
1853 * sample aspect ratio (0 if unknown)
1854 * That is the width of a pixel divided by the height of the pixel.
1855 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1856 * - encoding: Set by user.
1857 * - decoding: Set by libavcodec.
1859 AVRational sample_aspect_ratio;
1862 * motion estimation comparison function
1863 * - encoding: Set by user.
1864 * - decoding: unused
1868 * subpixel motion estimation comparison function
1869 * - encoding: Set by user.
1870 * - decoding: unused
1874 * macroblock comparison function (not supported yet)
1875 * - encoding: Set by user.
1876 * - decoding: unused
1880 * interlaced DCT comparison function
1881 * - encoding: Set by user.
1882 * - decoding: unused
1885 #define FF_CMP_SAD 0
1886 #define FF_CMP_SSE 1
1887 #define FF_CMP_SATD 2
1888 #define FF_CMP_DCT 3
1889 #define FF_CMP_PSNR 4
1890 #define FF_CMP_BIT 5
1892 #define FF_CMP_ZERO 7
1893 #define FF_CMP_VSAD 8
1894 #define FF_CMP_VSSE 9
1895 #define FF_CMP_NSSE 10
1896 #define FF_CMP_W53 11
1897 #define FF_CMP_W97 12
1898 #define FF_CMP_DCTMAX 13
1899 #define FF_CMP_DCT264 14
1900 #define FF_CMP_MEDIAN_SAD 15
1901 #define FF_CMP_CHROMA 256
1904 * ME diamond size & shape
1905 * - encoding: Set by user.
1906 * - decoding: unused
1911 * amount of previous MV predictors (2a+1 x 2a+1 square)
1912 * - encoding: Set by user.
1913 * - decoding: unused
1915 int last_predictor_count;
1917 #if FF_API_PRIVATE_OPT
1918 /** @deprecated use encoder private options instead */
1919 attribute_deprecated
1924 * motion estimation prepass comparison function
1925 * - encoding: Set by user.
1926 * - decoding: unused
1931 * ME prepass diamond size & shape
1932 * - encoding: Set by user.
1933 * - decoding: unused
1939 * - encoding: Set by user.
1940 * - decoding: unused
1942 int me_subpel_quality;
1945 * maximum motion estimation search range in subpel units
1946 * If 0 then no limit.
1948 * - encoding: Set by user.
1949 * - decoding: unused
1955 * - encoding: unused
1956 * - decoding: Set by user.
1959 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1960 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1961 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1964 * macroblock decision mode
1965 * - encoding: Set by user.
1966 * - decoding: unused
1969 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1970 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1971 #define FF_MB_DECISION_RD 2 ///< rate distortion
1974 * custom intra quantization matrix
1975 * - encoding: Set by user, can be NULL.
1976 * - decoding: Set by libavcodec.
1978 uint16_t *intra_matrix;
1981 * custom inter quantization matrix
1982 * - encoding: Set by user, can be NULL.
1983 * - decoding: Set by libavcodec.
1985 uint16_t *inter_matrix;
1987 #if FF_API_PRIVATE_OPT
1988 /** @deprecated use encoder private options instead */
1989 attribute_deprecated
1990 int scenechange_threshold;
1992 /** @deprecated use encoder private options instead */
1993 attribute_deprecated
1994 int noise_reduction;
1998 * precision of the intra DC coefficient - 8
1999 * - encoding: Set by user.
2000 * - decoding: Set by libavcodec
2002 int intra_dc_precision;
2005 * Number of macroblock rows at the top which are skipped.
2006 * - encoding: unused
2007 * - decoding: Set by user.
2012 * Number of macroblock rows at the bottom which are skipped.
2013 * - encoding: unused
2014 * - decoding: Set by user.
2019 * minimum MB Lagrange multiplier
2020 * - encoding: Set by user.
2021 * - decoding: unused
2026 * maximum MB Lagrange multiplier
2027 * - encoding: Set by user.
2028 * - decoding: unused
2032 #if FF_API_PRIVATE_OPT
2034 * @deprecated use encoder private options instead
2036 attribute_deprecated
2037 int me_penalty_compensation;
2041 * - encoding: Set by user.
2042 * - decoding: unused
2046 #if FF_API_PRIVATE_OPT
2047 /** @deprecated use encoder private options instead */
2048 attribute_deprecated
2054 * - encoding: Set by user.
2055 * - decoding: unused
2060 * number of reference frames
2061 * - encoding: Set by user.
2062 * - decoding: Set by lavc.
2066 #if FF_API_PRIVATE_OPT
2067 /** @deprecated use encoder private options instead */
2068 attribute_deprecated
2073 * Note: Value depends upon the compare function used for fullpel ME.
2074 * - encoding: Set by user.
2075 * - decoding: unused
2079 #if FF_API_PRIVATE_OPT
2080 /** @deprecated use encoder private options instead */
2081 attribute_deprecated
2086 * Chromaticity coordinates of the source primaries.
2087 * - encoding: Set by user
2088 * - decoding: Set by libavcodec
2090 enum AVColorPrimaries color_primaries;
2093 * Color Transfer Characteristic.
2094 * - encoding: Set by user
2095 * - decoding: Set by libavcodec
2097 enum AVColorTransferCharacteristic color_trc;
2100 * YUV colorspace type.
2101 * - encoding: Set by user
2102 * - decoding: Set by libavcodec
2104 enum AVColorSpace colorspace;
2107 * MPEG vs JPEG YUV range.
2108 * - encoding: Set by user
2109 * - decoding: Set by libavcodec
2111 enum AVColorRange color_range;
2114 * This defines the location of chroma samples.
2115 * - encoding: Set by user
2116 * - decoding: Set by libavcodec
2118 enum AVChromaLocation chroma_sample_location;
2122 * Indicates number of picture subdivisions. Used for parallelized
2124 * - encoding: Set by user
2125 * - decoding: unused
2130 * - encoding: set by libavcodec
2131 * - decoding: Set by user.
2133 enum AVFieldOrder field_order;
2136 int sample_rate; ///< samples per second
2137 int channels; ///< number of audio channels
2140 * audio sample format
2141 * - encoding: Set by user.
2142 * - decoding: Set by libavcodec.
2144 enum AVSampleFormat sample_fmt; ///< sample format
2146 /* The following data should not be initialized. */
2148 * Number of samples per channel in an audio frame.
2150 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2151 * except the last must contain exactly frame_size samples per channel.
2152 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2153 * frame size is not restricted.
2154 * - decoding: may be set by some decoders to indicate constant frame size
2159 * Frame counter, set by libavcodec.
2161 * - decoding: total number of frames returned from the decoder so far.
2162 * - encoding: total number of frames passed to the encoder so far.
2164 * @note the counter is not incremented if encoding/decoding resulted in
2170 * number of bytes per packet if constant and known or 0
2171 * Used by some WAV based audio codecs.
2176 * Audio cutoff bandwidth (0 means "automatic")
2177 * - encoding: Set by user.
2178 * - decoding: unused
2183 * Audio channel layout.
2184 * - encoding: set by user.
2185 * - decoding: set by user, may be overwritten by libavcodec.
2187 uint64_t channel_layout;
2190 * Request decoder to use this channel layout if it can (0 for default)
2191 * - encoding: unused
2192 * - decoding: Set by user.
2194 uint64_t request_channel_layout;
2197 * Type of service that the audio stream conveys.
2198 * - encoding: Set by user.
2199 * - decoding: Set by libavcodec.
2201 enum AVAudioServiceType audio_service_type;
2204 * desired sample format
2205 * - encoding: Not used.
2206 * - decoding: Set by user.
2207 * Decoder will decode to this format if it can.
2209 enum AVSampleFormat request_sample_fmt;
2212 * This callback is called at the beginning of each frame to get data
2213 * buffer(s) for it. There may be one contiguous buffer for all the data or
2214 * there may be a buffer per each data plane or anything in between. What
2215 * this means is, you may set however many entries in buf[] you feel necessary.
2216 * Each buffer must be reference-counted using the AVBuffer API (see description
2219 * The following fields will be set in the frame before this callback is
2222 * - width, height (video only)
2223 * - sample_rate, channel_layout, nb_samples (audio only)
2224 * Their values may differ from the corresponding values in
2225 * AVCodecContext. This callback must use the frame values, not the codec
2226 * context values, to calculate the required buffer size.
2228 * This callback must fill the following fields in the frame:
2232 * * if the data is planar audio with more than 8 channels, then this
2233 * callback must allocate and fill extended_data to contain all pointers
2234 * to all data planes. data[] must hold as many pointers as it can.
2235 * extended_data must be allocated with av_malloc() and will be freed in
2237 * * otherwise extended_data must point to data
2238 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2239 * the frame's data and extended_data pointers must be contained in these. That
2240 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2241 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2242 * and av_buffer_ref().
2243 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2244 * this callback and filled with the extra buffers if there are more
2245 * buffers than buf[] can hold. extended_buf will be freed in
2248 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2249 * avcodec_default_get_buffer2() instead of providing buffers allocated by
2252 * Each data plane must be aligned to the maximum required by the target
2255 * @see avcodec_default_get_buffer2()
2259 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2260 * (read and/or written to if it is writable) later by libavcodec.
2262 * avcodec_align_dimensions2() should be used to find the required width and
2263 * height, as they normally need to be rounded up to the next multiple of 16.
2265 * Some decoders do not support linesizes changing between frames.
2267 * If frame multithreading is used and thread_safe_callbacks is set,
2268 * this callback may be called from a different thread, but not from more
2269 * than one at once. Does not need to be reentrant.
2271 * @see avcodec_align_dimensions2()
2275 * Decoders request a buffer of a particular size by setting
2276 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2277 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2278 * to a smaller value in the output frame.
2280 * As a convenience, av_samples_get_buffer_size() and
2281 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2282 * functions to find the required data size and to fill data pointers and
2283 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2284 * since all planes must be the same size.
2286 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2288 * - encoding: unused
2289 * - decoding: Set by libavcodec, user can override.
2291 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2294 * If non-zero, the decoded audio and video frames returned from
2295 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2296 * and are valid indefinitely. The caller must free them with
2297 * av_frame_unref() when they are not needed anymore.
2298 * Otherwise, the decoded frames must not be freed by the caller and are
2299 * only valid until the next decode call.
2301 * This is always automatically enabled if avcodec_receive_frame() is used.
2303 * - encoding: unused
2304 * - decoding: set by the caller before avcodec_open2().
2306 attribute_deprecated
2307 int refcounted_frames;
2309 /* - encoding parameters */
2310 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2311 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2315 * - encoding: Set by user.
2316 * - decoding: unused
2322 * - encoding: Set by user.
2323 * - decoding: unused
2328 * maximum quantizer difference between frames
2329 * - encoding: Set by user.
2330 * - decoding: unused
2335 * decoder bitstream buffer size
2336 * - encoding: Set by user.
2337 * - decoding: unused
2342 * ratecontrol override, see RcOverride
2343 * - encoding: Allocated/set/freed by user.
2344 * - decoding: unused
2346 int rc_override_count;
2347 RcOverride *rc_override;
2351 * - encoding: Set by user.
2352 * - decoding: Set by user, may be overwritten by libavcodec.
2354 int64_t rc_max_rate;
2358 * - encoding: Set by user.
2359 * - decoding: unused
2361 int64_t rc_min_rate;
2364 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2365 * - encoding: Set by user.
2366 * - decoding: unused.
2368 float rc_max_available_vbv_use;
2371 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2372 * - encoding: Set by user.
2373 * - decoding: unused.
2375 float rc_min_vbv_overflow_use;
2378 * Number of bits which should be loaded into the rc buffer before decoding starts.
2379 * - encoding: Set by user.
2380 * - decoding: unused
2382 int rc_initial_buffer_occupancy;
2384 #if FF_API_CODER_TYPE
2385 #define FF_CODER_TYPE_VLC 0
2386 #define FF_CODER_TYPE_AC 1
2387 #define FF_CODER_TYPE_RAW 2
2388 #define FF_CODER_TYPE_RLE 3
2390 * @deprecated use encoder private options instead
2392 attribute_deprecated
2394 #endif /* FF_API_CODER_TYPE */
2396 #if FF_API_PRIVATE_OPT
2397 /** @deprecated use encoder private options instead */
2398 attribute_deprecated
2402 #if FF_API_PRIVATE_OPT
2403 /** @deprecated use encoder private options instead */
2404 attribute_deprecated
2405 int frame_skip_threshold;
2407 /** @deprecated use encoder private options instead */
2408 attribute_deprecated
2409 int frame_skip_factor;
2411 /** @deprecated use encoder private options instead */
2412 attribute_deprecated
2415 /** @deprecated use encoder private options instead */
2416 attribute_deprecated
2418 #endif /* FF_API_PRIVATE_OPT */
2421 * trellis RD quantization
2422 * - encoding: Set by user.
2423 * - decoding: unused
2427 #if FF_API_PRIVATE_OPT
2428 /** @deprecated use encoder private options instead */
2429 attribute_deprecated
2430 int min_prediction_order;
2432 /** @deprecated use encoder private options instead */
2433 attribute_deprecated
2434 int max_prediction_order;
2436 /** @deprecated use encoder private options instead */
2437 attribute_deprecated
2438 int64_t timecode_frame_start;
2441 #if FF_API_RTP_CALLBACK
2443 * @deprecated unused
2445 /* The RTP callback: This function is called */
2446 /* every time the encoder has a packet to send. */
2447 /* It depends on the encoder if the data starts */
2448 /* with a Start Code (it should). H.263 does. */
2449 /* mb_nb contains the number of macroblocks */
2450 /* encoded in the RTP payload. */
2451 attribute_deprecated
2452 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2455 #if FF_API_PRIVATE_OPT
2456 /** @deprecated use encoder private options instead */
2457 attribute_deprecated
2458 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2459 /* do its best to deliver a chunk with size */
2460 /* below rtp_payload_size, the chunk will start */
2461 /* with a start code on some codecs like H.263. */
2462 /* This doesn't take account of any particular */
2463 /* headers inside the transmitted RTP payload. */
2466 #if FF_API_STAT_BITS
2467 /* statistics, used for 2-pass encoding */
2468 attribute_deprecated
2470 attribute_deprecated
2472 attribute_deprecated
2474 attribute_deprecated
2476 attribute_deprecated
2478 attribute_deprecated
2480 attribute_deprecated
2482 attribute_deprecated
2485 /** @deprecated this field is unused */
2486 attribute_deprecated
2491 * pass1 encoding statistics output buffer
2492 * - encoding: Set by libavcodec.
2493 * - decoding: unused
2498 * pass2 encoding statistics input buffer
2499 * Concatenated stuff from stats_out of pass1 should be placed here.
2500 * - encoding: Allocated/set/freed by user.
2501 * - decoding: unused
2506 * Work around bugs in encoders which sometimes cannot be detected automatically.
2507 * - encoding: Set by user
2508 * - decoding: Set by user
2510 int workaround_bugs;
2511 #define FF_BUG_AUTODETECT 1 ///< autodetection
2512 #define FF_BUG_XVID_ILACE 4
2513 #define FF_BUG_UMP4 8
2514 #define FF_BUG_NO_PADDING 16
2515 #define FF_BUG_AMV 32
2516 #define FF_BUG_QPEL_CHROMA 64
2517 #define FF_BUG_STD_QPEL 128
2518 #define FF_BUG_QPEL_CHROMA2 256
2519 #define FF_BUG_DIRECT_BLOCKSIZE 512
2520 #define FF_BUG_EDGE 1024
2521 #define FF_BUG_HPEL_CHROMA 2048
2522 #define FF_BUG_DC_CLIP 4096
2523 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2524 #define FF_BUG_TRUNCATED 16384
2525 #define FF_BUG_IEDGE 32768
2528 * strictly follow the standard (MPEG-4, ...).
2529 * - encoding: Set by user.
2530 * - decoding: Set by user.
2531 * Setting this to STRICT or higher means the encoder and decoder will
2532 * generally do stupid things, whereas setting it to unofficial or lower
2533 * will mean the encoder might produce output that is not supported by all
2534 * spec-compliant decoders. Decoders don't differentiate between normal,
2535 * unofficial and experimental (that is, they always try to decode things
2536 * when they can) unless they are explicitly asked to behave stupidly
2537 * (=strictly conform to the specs)
2539 int strict_std_compliance;
2540 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2541 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2542 #define FF_COMPLIANCE_NORMAL 0
2543 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2544 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2547 * error concealment flags
2548 * - encoding: unused
2549 * - decoding: Set by user.
2551 int error_concealment;
2552 #define FF_EC_GUESS_MVS 1
2553 #define FF_EC_DEBLOCK 2
2554 #define FF_EC_FAVOR_INTER 256
2558 * - encoding: Set by user.
2559 * - decoding: Set by user.
2562 #define FF_DEBUG_PICT_INFO 1
2563 #define FF_DEBUG_RC 2
2564 #define FF_DEBUG_BITSTREAM 4
2565 #define FF_DEBUG_MB_TYPE 8
2566 #define FF_DEBUG_QP 16
2569 * @deprecated this option does nothing
2571 #define FF_DEBUG_MV 32
2573 #define FF_DEBUG_DCT_COEFF 0x00000040
2574 #define FF_DEBUG_SKIP 0x00000080
2575 #define FF_DEBUG_STARTCODE 0x00000100
2576 #define FF_DEBUG_ER 0x00000400
2577 #define FF_DEBUG_MMCO 0x00000800
2578 #define FF_DEBUG_BUGS 0x00001000
2580 #define FF_DEBUG_VIS_QP 0x00002000
2581 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2583 #define FF_DEBUG_BUFFERS 0x00008000
2584 #define FF_DEBUG_THREADS 0x00010000
2585 #define FF_DEBUG_GREEN_MD 0x00800000
2586 #define FF_DEBUG_NOMC 0x01000000
2591 * - encoding: Set by user.
2592 * - decoding: Set by user.
2595 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2596 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2597 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2601 * Error recognition; may misdetect some more or less valid parts as errors.
2602 * - encoding: unused
2603 * - decoding: Set by user.
2605 int err_recognition;
2608 * Verify checksums embedded in the bitstream (could be of either encoded or
2609 * decoded data, depending on the codec) and print an error message on mismatch.
2610 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2611 * decoder returning an error.
2613 #define AV_EF_CRCCHECK (1<<0)
2614 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2615 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2616 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2618 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2619 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
2620 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2621 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2625 * opaque 64-bit number (generally a PTS) that will be reordered and
2626 * output in AVFrame.reordered_opaque
2627 * - encoding: unused
2628 * - decoding: Set by user.
2630 int64_t reordered_opaque;
2633 * Hardware accelerator in use
2634 * - encoding: unused.
2635 * - decoding: Set by libavcodec
2637 struct AVHWAccel *hwaccel;
2640 * Hardware accelerator context.
2641 * For some hardware accelerators, a global context needs to be
2642 * provided by the user. In that case, this holds display-dependent
2643 * data FFmpeg cannot instantiate itself. Please refer to the
2644 * FFmpeg HW accelerator documentation to know how to fill this
2645 * is. e.g. for VA API, this is a struct vaapi_context.
2646 * - encoding: unused
2647 * - decoding: Set by user
2649 void *hwaccel_context;
2653 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2654 * - decoding: unused
2656 uint64_t error[AV_NUM_DATA_POINTERS];
2659 * DCT algorithm, see FF_DCT_* below
2660 * - encoding: Set by user.
2661 * - decoding: unused
2664 #define FF_DCT_AUTO 0
2665 #define FF_DCT_FASTINT 1
2666 #define FF_DCT_INT 2
2667 #define FF_DCT_MMX 3
2668 #define FF_DCT_ALTIVEC 5
2669 #define FF_DCT_FAAN 6
2672 * IDCT algorithm, see FF_IDCT_* below.
2673 * - encoding: Set by user.
2674 * - decoding: Set by user.
2677 #define FF_IDCT_AUTO 0
2678 #define FF_IDCT_INT 1
2679 #define FF_IDCT_SIMPLE 2
2680 #define FF_IDCT_SIMPLEMMX 3
2681 #define FF_IDCT_ARM 7
2682 #define FF_IDCT_ALTIVEC 8
2683 #define FF_IDCT_SIMPLEARM 10
2684 #define FF_IDCT_XVID 14
2685 #define FF_IDCT_SIMPLEARMV5TE 16
2686 #define FF_IDCT_SIMPLEARMV6 17
2687 #define FF_IDCT_FAAN 20
2688 #define FF_IDCT_SIMPLENEON 22
2689 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2690 #define FF_IDCT_SIMPLEAUTO 128
2693 * bits per sample/pixel from the demuxer (needed for huffyuv).
2694 * - encoding: Set by libavcodec.
2695 * - decoding: Set by user.
2697 int bits_per_coded_sample;
2700 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2701 * - encoding: set by user.
2702 * - decoding: set by libavcodec.
2704 int bits_per_raw_sample;
2708 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2709 * - encoding: unused
2710 * - decoding: Set by user.
2715 #if FF_API_CODED_FRAME
2717 * the picture in the bitstream
2718 * - encoding: Set by libavcodec.
2719 * - decoding: unused
2721 * @deprecated use the quality factor packet side data instead
2723 attribute_deprecated AVFrame *coded_frame;
2728 * is used to decide how many independent tasks should be passed to execute()
2729 * - encoding: Set by user.
2730 * - decoding: Set by user.
2735 * Which multithreading methods to use.
2736 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2737 * so clients which cannot provide future frames should not use it.
2739 * - encoding: Set by user, otherwise the default is used.
2740 * - decoding: Set by user, otherwise the default is used.
2743 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2744 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2747 * Which multithreading methods are in use by the codec.
2748 * - encoding: Set by libavcodec.
2749 * - decoding: Set by libavcodec.
2751 int active_thread_type;
2754 * Set by the client if its custom get_buffer() callback can be called
2755 * synchronously from another thread, which allows faster multithreaded decoding.
2756 * draw_horiz_band() will be called from other threads regardless of this setting.
2757 * Ignored if the default get_buffer() is used.
2758 * - encoding: Set by user.
2759 * - decoding: Set by user.
2761 int thread_safe_callbacks;
2764 * The codec may call this to execute several independent things.
2765 * It will return only after finishing all tasks.
2766 * The user may replace this with some multithreaded implementation,
2767 * the default implementation will execute the parts serially.
2768 * @param count the number of things to execute
2769 * - encoding: Set by libavcodec, user can override.
2770 * - decoding: Set by libavcodec, user can override.
2772 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2775 * The codec may call this to execute several independent things.
2776 * It will return only after finishing all tasks.
2777 * The user may replace this with some multithreaded implementation,
2778 * the default implementation will execute the parts serially.
2779 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2780 * @param c context passed also to func
2781 * @param count the number of things to execute
2782 * @param arg2 argument passed unchanged to func
2783 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2784 * @param func function that will be called count times, with jobnr from 0 to count-1.
2785 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2786 * two instances of func executing at the same time will have the same threadnr.
2787 * @return always 0 currently, but code should handle a future improvement where when any call to func
2788 * returns < 0 no further calls to func may be done and < 0 is returned.
2789 * - encoding: Set by libavcodec, user can override.
2790 * - decoding: Set by libavcodec, user can override.
2792 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2795 * noise vs. sse weight for the nsse comparison function
2796 * - encoding: Set by user.
2797 * - decoding: unused
2803 * - encoding: Set by user.
2804 * - decoding: Set by libavcodec.
2807 #define FF_PROFILE_UNKNOWN -99
2808 #define FF_PROFILE_RESERVED -100
2810 #define FF_PROFILE_AAC_MAIN 0
2811 #define FF_PROFILE_AAC_LOW 1
2812 #define FF_PROFILE_AAC_SSR 2
2813 #define FF_PROFILE_AAC_LTP 3
2814 #define FF_PROFILE_AAC_HE 4
2815 #define FF_PROFILE_AAC_HE_V2 28
2816 #define FF_PROFILE_AAC_LD 22
2817 #define FF_PROFILE_AAC_ELD 38
2818 #define FF_PROFILE_MPEG2_AAC_LOW 128
2819 #define FF_PROFILE_MPEG2_AAC_HE 131
2821 #define FF_PROFILE_DNXHD 0
2822 #define FF_PROFILE_DNXHR_LB 1
2823 #define FF_PROFILE_DNXHR_SQ 2
2824 #define FF_PROFILE_DNXHR_HQ 3
2825 #define FF_PROFILE_DNXHR_HQX 4
2826 #define FF_PROFILE_DNXHR_444 5
2828 #define FF_PROFILE_DTS 20
2829 #define FF_PROFILE_DTS_ES 30
2830 #define FF_PROFILE_DTS_96_24 40
2831 #define FF_PROFILE_DTS_HD_HRA 50
2832 #define FF_PROFILE_DTS_HD_MA 60
2833 #define FF_PROFILE_DTS_EXPRESS 70
2835 #define FF_PROFILE_MPEG2_422 0
2836 #define FF_PROFILE_MPEG2_HIGH 1
2837 #define FF_PROFILE_MPEG2_SS 2
2838 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2839 #define FF_PROFILE_MPEG2_MAIN 4
2840 #define FF_PROFILE_MPEG2_SIMPLE 5
2842 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2843 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2845 #define FF_PROFILE_H264_BASELINE 66
2846 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2847 #define FF_PROFILE_H264_MAIN 77
2848 #define FF_PROFILE_H264_EXTENDED 88
2849 #define FF_PROFILE_H264_HIGH 100
2850 #define FF_PROFILE_H264_HIGH_10 110
2851 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2852 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2853 #define FF_PROFILE_H264_HIGH_422 122
2854 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2855 #define FF_PROFILE_H264_STEREO_HIGH 128
2856 #define FF_PROFILE_H264_HIGH_444 144
2857 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2858 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2859 #define FF_PROFILE_H264_CAVLC_444 44
2861 #define FF_PROFILE_VC1_SIMPLE 0
2862 #define FF_PROFILE_VC1_MAIN 1
2863 #define FF_PROFILE_VC1_COMPLEX 2
2864 #define FF_PROFILE_VC1_ADVANCED 3
2866 #define FF_PROFILE_MPEG4_SIMPLE 0
2867 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2868 #define FF_PROFILE_MPEG4_CORE 2
2869 #define FF_PROFILE_MPEG4_MAIN 3
2870 #define FF_PROFILE_MPEG4_N_BIT 4
2871 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2872 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2873 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2874 #define FF_PROFILE_MPEG4_HYBRID 8
2875 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2876 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2877 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2878 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2879 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2880 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2881 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2883 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2884 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2885 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2886 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2887 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2889 #define FF_PROFILE_VP9_0 0
2890 #define FF_PROFILE_VP9_1 1
2891 #define FF_PROFILE_VP9_2 2
2892 #define FF_PROFILE_VP9_3 3
2894 #define FF_PROFILE_HEVC_MAIN 1
2895 #define FF_PROFILE_HEVC_MAIN_10 2
2896 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2897 #define FF_PROFILE_HEVC_REXT 4
2901 * - encoding: Set by user.
2902 * - decoding: Set by libavcodec.
2905 #define FF_LEVEL_UNKNOWN -99
2908 * Skip loop filtering for selected frames.
2909 * - encoding: unused
2910 * - decoding: Set by user.
2912 enum AVDiscard skip_loop_filter;
2915 * Skip IDCT/dequantization for selected frames.
2916 * - encoding: unused
2917 * - decoding: Set by user.
2919 enum AVDiscard skip_idct;
2922 * Skip decoding for selected frames.
2923 * - encoding: unused
2924 * - decoding: Set by user.
2926 enum AVDiscard skip_frame;
2929 * Header containing style information for text subtitles.
2930 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2931 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2932 * the Format line following. It shouldn't include any Dialogue line.
2933 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2934 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2936 uint8_t *subtitle_header;
2937 int subtitle_header_size;
2939 #if FF_API_VBV_DELAY
2941 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2942 * Used for compliant TS muxing.
2943 * - encoding: Set by libavcodec.
2944 * - decoding: unused.
2945 * @deprecated this value is now exported as a part of
2946 * AV_PKT_DATA_CPB_PROPERTIES packet side data
2948 attribute_deprecated
2952 #if FF_API_SIDEDATA_ONLY_PKT
2954 * Encoding only and set by default. Allow encoders to output packets
2955 * that do not contain any encoded data, only side data.
2957 * Some encoders need to output such packets, e.g. to update some stream
2958 * parameters at the end of encoding.
2960 * @deprecated this field disables the default behaviour and
2961 * it is kept only for compatibility.
2963 attribute_deprecated
2964 int side_data_only_packets;
2968 * Audio only. The number of "priming" samples (padding) inserted by the
2969 * encoder at the beginning of the audio. I.e. this number of leading
2970 * decoded samples must be discarded by the caller to get the original audio
2971 * without leading padding.
2973 * - decoding: unused
2974 * - encoding: Set by libavcodec. The timestamps on the output packets are
2975 * adjusted by the encoder so that they always refer to the
2976 * first sample of the data actually contained in the packet,
2977 * including any added padding. E.g. if the timebase is
2978 * 1/samplerate and the timestamp of the first input sample is
2979 * 0, the timestamp of the first output packet will be
2982 int initial_padding;
2985 * - decoding: For codecs that store a framerate value in the compressed
2986 * bitstream, the decoder may export it here. { 0, 1} when
2988 * - encoding: May be used to signal the framerate of CFR content to an
2991 AVRational framerate;
2994 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2995 * - encoding: unused.
2996 * - decoding: Set by libavcodec before calling get_format()
2998 enum AVPixelFormat sw_pix_fmt;
3001 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3002 * - encoding unused.
3003 * - decoding set by user.
3005 AVRational pkt_timebase;
3009 * - encoding: unused.
3010 * - decoding: set by libavcodec.
3012 const AVCodecDescriptor *codec_descriptor;
3016 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3017 * - encoding: unused
3018 * - decoding: Set by user.
3024 * Current statistics for PTS correction.
3025 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3026 * - encoding: unused
3028 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3029 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3030 int64_t pts_correction_last_pts; /// PTS of the last frame
3031 int64_t pts_correction_last_dts; /// DTS of the last frame
3034 * Character encoding of the input subtitles file.
3035 * - decoding: set by user
3036 * - encoding: unused
3041 * Subtitles character encoding mode. Formats or codecs might be adjusting
3042 * this setting (if they are doing the conversion themselves for instance).
3043 * - decoding: set by libavcodec
3044 * - encoding: unused
3046 int sub_charenc_mode;
3047 #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)
3048 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3049 #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
3052 * Skip processing alpha if supported by codec.
3053 * Note that if the format uses pre-multiplied alpha (common with VP6,
3054 * and recommended due to better video quality/compression)
3055 * the image will look as if alpha-blended onto a black background.
3056 * However for formats that do not use pre-multiplied alpha
3057 * there might be serious artefacts (though e.g. libswscale currently
3058 * assumes pre-multiplied alpha anyway).
3060 * - decoding: set by user
3061 * - encoding: unused
3066 * Number of samples to skip after a discontinuity
3067 * - decoding: unused
3068 * - encoding: set by libavcodec
3072 #if !FF_API_DEBUG_MV
3074 * debug motion vectors
3075 * - encoding: Set by user.
3076 * - decoding: Set by user.
3079 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3080 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3081 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3085 * custom intra quantization matrix
3086 * - encoding: Set by user, can be NULL.
3087 * - decoding: unused.
3089 uint16_t *chroma_intra_matrix;
3092 * dump format separator.
3093 * can be ", " or "\n " or anything else
3094 * - encoding: Set by user.
3095 * - decoding: Set by user.
3097 uint8_t *dump_separator;
3100 * ',' separated list of allowed decoders.
3101 * If NULL then all are allowed
3102 * - encoding: unused
3103 * - decoding: set by user
3105 char *codec_whitelist;
3108 * Properties of the stream that gets decoded
3109 * - encoding: unused
3110 * - decoding: set by libavcodec
3112 unsigned properties;
3113 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3114 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3117 * Additional data associated with the entire coded stream.
3119 * - decoding: unused
3120 * - encoding: may be set by libavcodec after avcodec_open2().
3122 AVPacketSideData *coded_side_data;
3123 int nb_coded_side_data;
3126 * A reference to the AVHWFramesContext describing the input (for encoding)
3127 * or output (decoding) frames. The reference is set by the caller and
3128 * afterwards owned (and freed) by libavcodec - it should never be read by
3129 * the caller after being set.
3131 * - decoding: This field should be set by the caller from the get_format()
3132 * callback. The previous reference (if any) will always be
3133 * unreffed by libavcodec before the get_format() call.
3135 * If the default get_buffer2() is used with a hwaccel pixel
3136 * format, then this AVHWFramesContext will be used for
3137 * allocating the frame buffers.
3139 * - encoding: For hardware encoders configured to use a hwaccel pixel
3140 * format, this field should be set by the caller to a reference
3141 * to the AVHWFramesContext describing input frames.
3142 * AVHWFramesContext.format must be equal to
3143 * AVCodecContext.pix_fmt.
3145 * This field should be set before avcodec_open2() is called.
3147 AVBufferRef *hw_frames_ctx;
3150 * Control the form of AVSubtitle.rects[N]->ass
3151 * - decoding: set by user
3152 * - encoding: unused
3154 int sub_text_format;
3155 #define FF_SUB_TEXT_FMT_ASS 0
3156 #if FF_API_ASS_TIMING
3157 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3161 * Audio only. The amount of padding (in samples) appended by the encoder to
3162 * the end of the audio. I.e. this number of decoded samples must be
3163 * discarded by the caller from the end of the stream to get the original
3164 * audio without any trailing padding.
3166 * - decoding: unused
3167 * - encoding: unused
3169 int trailing_padding;
3172 * The number of pixels per image to maximally accept.
3174 * - decoding: set by user
3175 * - encoding: set by user
3180 * A reference to the AVHWDeviceContext describing the device which will
3181 * be used by a hardware encoder/decoder. The reference is set by the
3182 * caller and afterwards owned (and freed) by libavcodec.
3184 * This should be used if either the codec device does not require
3185 * hardware frames or any that are used are to be allocated internally by
3186 * libavcodec. If the user wishes to supply any of the frames used as
3187 * encoder input or decoder output then hw_frames_ctx should be used
3188 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3189 * field will be ignored while decoding the associated stream segment, but
3190 * may again be used on a following one after another get_format() call.
3192 * For both encoders and decoders this field should be set before
3193 * avcodec_open2() is called and must not be written to thereafter.
3195 * Note that some decoders may require this field to be set initially in
3196 * order to support hw_frames_ctx at all - in that case, all frames
3197 * contexts used must be created on the same device.
3199 AVBufferRef *hw_device_ctx;
3202 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3203 * decoding (if active).
3204 * - encoding: unused
3205 * - decoding: Set by user (either before avcodec_open2(), or in the
3206 * AVCodecContext.get_format callback)
3211 * Video decoding only. Certain video codecs support cropping, meaning that
3212 * only a sub-rectangle of the decoded frame is intended for display. This
3213 * option controls how cropping is handled by libavcodec.
3215 * When set to 1 (the default), libavcodec will apply cropping internally.
3216 * I.e. it will modify the output frame width/height fields and offset the
3217 * data pointers (only by as much as possible while preserving alignment, or
3218 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3219 * the frames output by the decoder refer only to the cropped area. The
3220 * crop_* fields of the output frames will be zero.
3222 * When set to 0, the width/height fields of the output frames will be set
3223 * to the coded dimensions and the crop_* fields will describe the cropping
3224 * rectangle. Applying the cropping is left to the caller.
3226 * @warning When hardware acceleration with opaque output frames is used,
3227 * libavcodec is unable to apply cropping from the top/left border.
3229 * @note when this option is set to zero, the width/height fields of the
3230 * AVCodecContext and output AVFrames have different meanings. The codec
3231 * context fields store display dimensions (with the coded dimensions in
3232 * coded_width/height), while the frame fields store the coded dimensions
3233 * (with the display dimensions being determined by the crop_* fields).
3238 #if FF_API_CODEC_GET_SET
3240 * Accessors for some AVCodecContext fields. These used to be provided for ABI
3241 * compatibility, and do not need to be used anymore.
3243 attribute_deprecated
3244 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3245 attribute_deprecated
3246 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3248 attribute_deprecated
3249 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3250 attribute_deprecated
3251 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3253 attribute_deprecated
3254 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3257 attribute_deprecated
3258 int av_codec_get_lowres(const AVCodecContext *avctx);
3259 attribute_deprecated
3260 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3263 attribute_deprecated
3264 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3265 attribute_deprecated
3266 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3268 attribute_deprecated
3269 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3270 attribute_deprecated
3271 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3277 typedef struct AVProfile {
3279 const char *name; ///< short name for the profile
3282 typedef struct AVCodecDefault AVCodecDefault;
3289 typedef struct AVCodec {
3291 * Name of the codec implementation.
3292 * The name is globally unique among encoders and among decoders (but an
3293 * encoder and a decoder can share the same name).
3294 * This is the primary way to find a codec from the user perspective.
3298 * Descriptive name for the codec, meant to be more human readable than name.
3299 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3301 const char *long_name;
3302 enum AVMediaType type;
3305 * Codec capabilities.
3306 * see AV_CODEC_CAP_*
3309 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3310 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3311 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3312 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3313 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3314 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3315 const AVClass *priv_class; ///< AVClass for the private context
3316 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3318 /*****************************************************************
3319 * No fields below this line are part of the public API. They
3320 * may not be used outside of libavcodec and can be changed and
3322 * New public fields should be added right above.
3323 *****************************************************************
3326 struct AVCodec *next;
3328 * @name Frame-level threading support functions
3332 * If defined, called on thread contexts when they are created.
3333 * If the codec allocates writable tables in init(), re-allocate them here.
3334 * priv_data will be set to a copy of the original.
3336 int (*init_thread_copy)(AVCodecContext *);
3338 * Copy necessary context variables from a previous thread context to the current one.
3339 * If not defined, the next thread will start automatically; otherwise, the codec
3340 * must call ff_thread_finish_setup().
3342 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3344 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3348 * Private codec-specific defaults.
3350 const AVCodecDefault *defaults;
3353 * Initialize codec static data, called from avcodec_register().
3355 void (*init_static_data)(struct AVCodec *codec);
3357 int (*init)(AVCodecContext *);
3358 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3359 const struct AVSubtitle *sub);
3361 * Encode data to an AVPacket.
3363 * @param avctx codec context
3364 * @param avpkt output AVPacket (may contain a user-provided buffer)
3365 * @param[in] frame AVFrame containing the raw data to be encoded
3366 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3367 * non-empty packet was returned in avpkt.
3368 * @return 0 on success, negative error code on failure
3370 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3371 int *got_packet_ptr);
3372 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3373 int (*close)(AVCodecContext *);
3375 * Encode API with decoupled packet/frame dataflow. The API is the
3376 * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3378 * - never called if the codec is closed or the wrong type,
3379 * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3380 * - only one drain frame is ever passed down,
3382 int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3383 int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3386 * Decode API with decoupled packet/frame dataflow. This function is called
3387 * to get one output frame. It should call ff_decode_get_packet() to obtain
3390 int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
3393 * Will be called when seeking
3395 void (*flush)(AVCodecContext *);
3397 * Internal codec capabilities.
3398 * See FF_CODEC_CAP_* in internal.h
3403 * Decoding only, a comma-separated list of bitstream filters to apply to
3404 * packets before decoding.
3409 #if FF_API_CODEC_GET_SET
3410 attribute_deprecated
3411 int av_codec_get_max_lowres(const AVCodec *codec);
3414 struct MpegEncContext;
3417 * @defgroup lavc_hwaccel AVHWAccel
3420 typedef struct AVHWAccel {
3422 * Name of the hardware accelerated codec.
3423 * The name is globally unique among encoders and among decoders (but an
3424 * encoder and a decoder can share the same name).
3429 * Type of codec implemented by the hardware accelerator.
3431 * See AVMEDIA_TYPE_xxx
3433 enum AVMediaType type;
3436 * Codec implemented by the hardware accelerator.
3438 * See AV_CODEC_ID_xxx
3443 * Supported pixel format.
3445 * Only hardware accelerated formats are supported here.
3447 enum AVPixelFormat pix_fmt;
3450 * Hardware accelerated codec capabilities.
3451 * see AV_HWACCEL_CODEC_CAP_*
3455 /*****************************************************************
3456 * No fields below this line are part of the public API. They
3457 * may not be used outside of libavcodec and can be changed and
3459 * New public fields should be added right above.
3460 *****************************************************************
3462 struct AVHWAccel *next;
3465 * Allocate a custom buffer
3467 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
3470 * Called at the beginning of each frame or field picture.
3472 * Meaningful frame information (codec specific) is guaranteed to
3473 * be parsed at this point. This function is mandatory.
3475 * Note that buf can be NULL along with buf_size set to 0.
3476 * Otherwise, this means the whole frame is available at this point.
3478 * @param avctx the codec context
3479 * @param buf the frame data buffer base
3480 * @param buf_size the size of the frame in bytes
3481 * @return zero if successful, a negative value otherwise
3483 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3486 * Callback for parameter data (SPS/PPS/VPS etc).
3488 * Useful for hardware decoders which keep persistent state about the
3489 * video parameters, and need to receive any changes to update that state.
3491 * @param avctx the codec context
3492 * @param type the nal unit type
3493 * @param buf the nal unit data buffer
3494 * @param buf_size the size of the nal unit in bytes
3495 * @return zero if successful, a negative value otherwise
3497 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3500 * Callback for each slice.
3502 * Meaningful slice information (codec specific) is guaranteed to
3503 * be parsed at this point. This function is mandatory.
3504 * The only exception is XvMC, that works on MB level.
3506 * @param avctx the codec context
3507 * @param buf the slice data buffer base
3508 * @param buf_size the size of the slice in bytes
3509 * @return zero if successful, a negative value otherwise
3511 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3514 * Called at the end of each frame or field picture.
3516 * The whole picture is parsed at this point and can now be sent
3517 * to the hardware accelerator. This function is mandatory.
3519 * @param avctx the codec context
3520 * @return zero if successful, a negative value otherwise
3522 int (*end_frame)(AVCodecContext *avctx);
3525 * Size of per-frame hardware accelerator private data.
3527 * Private data is allocated with av_mallocz() before
3528 * AVCodecContext.get_buffer() and deallocated after
3529 * AVCodecContext.release_buffer().
3531 int frame_priv_data_size;
3534 * Called for every Macroblock in a slice.
3536 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3537 * Instead of decoding to raw picture, MB parameters are
3538 * stored in an array provided by the video driver.
3540 * @param s the mpeg context
3542 void (*decode_mb)(struct MpegEncContext *s);
3545 * Initialize the hwaccel private data.
3547 * This will be called from ff_get_format(), after hwaccel and
3548 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3551 int (*init)(AVCodecContext *avctx);
3554 * Uninitialize the hwaccel private data.
3556 * This will be called from get_format() or avcodec_close(), after hwaccel
3557 * and hwaccel_context are already uninitialized.
3559 int (*uninit)(AVCodecContext *avctx);
3562 * Size of the private data to allocate in
3563 * AVCodecInternal.hwaccel_priv_data.
3568 * Internal hwaccel capabilities.
3573 * Fill the given hw_frames context with current codec parameters. Called
3574 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3577 * This CAN be called before AVHWAccel.init is called, and you must assume
3578 * that avctx->hwaccel_priv_data is invalid.
3580 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3583 * Some hwaccels are ambiguous if only the id and pix_fmt fields are used.
3584 * If non-NULL, the associated AVCodec must have
3585 * FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS set.
3587 const AVClass *decoder_class;
3591 * HWAccel is experimental and is thus avoided in favor of non experimental
3594 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3597 * Hardware acceleration should be used for decoding even if the codec level
3598 * used is unknown or higher than the maximum supported level reported by the
3601 * It's generally a good idea to pass this flag unless you have a specific
3602 * reason not to, as hardware tends to under-report supported levels.
3604 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3607 * Hardware acceleration can output YUV pixel formats with a different chroma
3608 * sampling than 4:2:0 and/or other than 8 bits per component.
3610 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3613 * Hardware acceleration should still be attempted for decoding when the
3614 * codec profile does not match the reported capabilities of the hardware.
3616 * For example, this can be used to try to decode baseline profile H.264
3617 * streams in hardware - it will often succeed, because many streams marked
3618 * as baseline profile actually conform to constrained baseline profile.
3620 * @warning If the stream is actually not supported then the behaviour is
3621 * undefined, and may include returning entirely incorrect output
3622 * while indicating success.
3624 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3630 #if FF_API_AVPICTURE
3632 * @defgroup lavc_picture AVPicture
3634 * Functions for working with AVPicture
3639 * Picture data structure.
3641 * Up to four components can be stored into it, the last component is
3643 * @deprecated use AVFrame or imgutils functions instead
3645 typedef struct AVPicture {
3646 attribute_deprecated
3647 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3648 attribute_deprecated
3649 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3657 enum AVSubtitleType {
3660 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3663 * Plain text, the text field must be set by the decoder and is
3664 * authoritative. ass and pict fields may contain approximations.
3669 * Formatted text, the ass field must be set by the decoder and is
3670 * authoritative. pict and text fields may contain approximations.
3675 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3677 typedef struct AVSubtitleRect {
3678 int x; ///< top left corner of pict, undefined when pict is not set
3679 int y; ///< top left corner of pict, undefined when pict is not set
3680 int w; ///< width of pict, undefined when pict is not set
3681 int h; ///< height of pict, undefined when pict is not set
3682 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3684 #if FF_API_AVPICTURE
3686 * @deprecated unused
3688 attribute_deprecated
3692 * data+linesize for the bitmap of this subtitle.
3693 * Can be set for text/ass as well once they are rendered.
3698 enum AVSubtitleType type;
3700 char *text; ///< 0 terminated plain UTF-8 text
3703 * 0 terminated ASS/SSA compatible event line.
3704 * The presentation of this is unaffected by the other values in this
3712 typedef struct AVSubtitle {
3713 uint16_t format; /* 0 = graphics */
3714 uint32_t start_display_time; /* relative to packet pts, in ms */
3715 uint32_t end_display_time; /* relative to packet pts, in ms */
3717 AVSubtitleRect **rects;
3718 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3722 * This struct describes the properties of an encoded stream.
3724 * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3725 * be allocated with avcodec_parameters_alloc() and freed with
3726 * avcodec_parameters_free().
3728 typedef struct AVCodecParameters {
3730 * General type of the encoded data.
3732 enum AVMediaType codec_type;
3734 * Specific type of the encoded data (the codec used).
3736 enum AVCodecID codec_id;
3738 * Additional information about the codec (corresponds to the AVI FOURCC).
3743 * Extra binary data needed for initializing the decoder, codec-dependent.
3745 * Must be allocated with av_malloc() and will be freed by
3746 * avcodec_parameters_free(). The allocated size of extradata must be at
3747 * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3752 * Size of the extradata content in bytes.
3757 * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3758 * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3763 * The average bitrate of the encoded data (in bits per second).
3768 * The number of bits per sample in the codedwords.
3770 * This is basically the bitrate per sample. It is mandatory for a bunch of
3771 * formats to actually decode them. It's the number of bits for one sample in
3772 * the actual coded bitstream.
3774 * This could be for example 4 for ADPCM
3775 * For PCM formats this matches bits_per_raw_sample
3778 int bits_per_coded_sample;
3781 * This is the number of valid bits in each output sample. If the
3782 * sample format has more bits, the least significant bits are additional
3783 * padding bits, which are always 0. Use right shifts to reduce the sample
3784 * to its actual size. For example, audio formats with 24 bit samples will
3785 * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3786 * To get the original sample use "(int32_t)sample >> 8"."
3788 * For ADPCM this might be 12 or 16 or similar
3791 int bits_per_raw_sample;
3794 * Codec-specific bitstream restrictions that the stream conforms to.
3800 * Video only. The dimensions of the video frame in pixels.
3806 * Video only. The aspect ratio (width / height) which a single pixel
3807 * should have when displayed.
3809 * When the aspect ratio is unknown / undefined, the numerator should be
3810 * set to 0 (the denominator may have any value).
3812 AVRational sample_aspect_ratio;
3815 * Video only. The order of the fields in interlaced video.
3817 enum AVFieldOrder field_order;
3820 * Video only. Additional colorspace characteristics.
3822 enum AVColorRange color_range;
3823 enum AVColorPrimaries color_primaries;
3824 enum AVColorTransferCharacteristic color_trc;
3825 enum AVColorSpace color_space;
3826 enum AVChromaLocation chroma_location;
3829 * Video only. Number of delayed frames.
3834 * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3835 * unknown or unspecified, otherwise the number of bits set must be equal to
3836 * the channels field.
3838 uint64_t channel_layout;
3840 * Audio only. The number of audio channels.
3844 * Audio only. The number of audio samples per second.
3848 * Audio only. The number of bytes per coded audio frame, required by some
3851 * Corresponds to nBlockAlign in WAVEFORMATEX.
3855 * Audio only. Audio frame size, if known. Required by some formats to be static.
3860 * Audio only. The amount of padding (in samples) inserted by the encoder at
3861 * the beginning of the audio. I.e. this number of leading decoded samples
3862 * must be discarded by the caller to get the original audio without leading
3865 int initial_padding;
3867 * Audio only. The amount of padding (in samples) appended by the encoder to
3868 * the end of the audio. I.e. this number of decoded samples must be
3869 * discarded by the caller from the end of the stream to get the original
3870 * audio without any trailing padding.
3872 int trailing_padding;
3874 * Audio only. Number of samples to skip after a discontinuity.
3877 } AVCodecParameters;
3880 * If c is NULL, returns the first registered codec,
3881 * if c is non-NULL, returns the next registered codec after c,
3882 * or NULL if c is the last one.
3884 AVCodec *av_codec_next(const AVCodec *c);
3887 * Return the LIBAVCODEC_VERSION_INT constant.
3889 unsigned avcodec_version(void);
3892 * Return the libavcodec build-time configuration.
3894 const char *avcodec_configuration(void);
3897 * Return the libavcodec license.
3899 const char *avcodec_license(void);
3902 * Register the codec codec and initialize libavcodec.
3904 * @warning either this function or avcodec_register_all() must be called
3905 * before any other libavcodec functions.
3907 * @see avcodec_register_all()
3909 void avcodec_register(AVCodec *codec);
3912 * Register all the codecs, parsers and bitstream filters which were enabled at
3913 * configuration time. If you do not call this function you can select exactly
3914 * which formats you want to support, by using the individual registration
3917 * @see avcodec_register
3918 * @see av_register_codec_parser
3919 * @see av_register_bitstream_filter
3921 void avcodec_register_all(void);
3924 * Allocate an AVCodecContext and set its fields to default values. The
3925 * resulting struct should be freed with avcodec_free_context().
3927 * @param codec if non-NULL, allocate private data and initialize defaults
3928 * for the given codec. It is illegal to then call avcodec_open2()
3929 * with a different codec.
3930 * If NULL, then the codec-specific defaults won't be initialized,
3931 * which may result in suboptimal default settings (this is
3932 * important mainly for encoders, e.g. libx264).
3934 * @return An AVCodecContext filled with default values or NULL on failure.
3936 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3939 * Free the codec context and everything associated with it and write NULL to
3940 * the provided pointer.
3942 void avcodec_free_context(AVCodecContext **avctx);
3944 #if FF_API_GET_CONTEXT_DEFAULTS
3946 * @deprecated This function should not be used, as closing and opening a codec
3947 * context multiple time is not supported. A new codec context should be
3948 * allocated for each new use.
3950 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3954 * Get the AVClass for AVCodecContext. It can be used in combination with
3955 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3957 * @see av_opt_find().
3959 const AVClass *avcodec_get_class(void);
3961 #if FF_API_COPY_CONTEXT
3963 * Get the AVClass for AVFrame. It can be used in combination with
3964 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3966 * @see av_opt_find().
3968 const AVClass *avcodec_get_frame_class(void);
3971 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3972 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3974 * @see av_opt_find().
3976 const AVClass *avcodec_get_subtitle_rect_class(void);
3979 * Copy the settings of the source AVCodecContext into the destination
3980 * AVCodecContext. The resulting destination codec context will be
3981 * unopened, i.e. you are required to call avcodec_open2() before you
3982 * can use this AVCodecContext to decode/encode video/audio data.
3984 * @param dest target codec context, should be initialized with
3985 * avcodec_alloc_context3(NULL), but otherwise uninitialized
3986 * @param src source codec context
3987 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3989 * @deprecated The semantics of this function are ill-defined and it should not
3990 * be used. If you need to transfer the stream parameters from one codec context
3991 * to another, use an intermediate AVCodecParameters instance and the
3992 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
3995 attribute_deprecated
3996 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
4000 * Allocate a new AVCodecParameters and set its fields to default values
4001 * (unknown/invalid/0). The returned struct must be freed with
4002 * avcodec_parameters_free().
4004 AVCodecParameters *avcodec_parameters_alloc(void);
4007 * Free an AVCodecParameters instance and everything associated with it and
4008 * write NULL to the supplied pointer.
4010 void avcodec_parameters_free(AVCodecParameters **par);
4013 * Copy the contents of src to dst. Any allocated fields in dst are freed and
4014 * replaced with newly allocated duplicates of the corresponding fields in src.
4016 * @return >= 0 on success, a negative AVERROR code on failure.
4018 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
4021 * Fill the parameters struct based on the values from the supplied codec
4022 * context. Any allocated fields in par are freed and replaced with duplicates
4023 * of the corresponding fields in codec.
4025 * @return >= 0 on success, a negative AVERROR code on failure
4027 int avcodec_parameters_from_context(AVCodecParameters *par,
4028 const AVCodecContext *codec);
4031 * Fill the codec context based on the values from the supplied codec
4032 * parameters. Any allocated fields in codec that have a corresponding field in
4033 * par are freed and replaced with duplicates of the corresponding field in par.
4034 * Fields in codec that do not have a counterpart in par are not touched.
4036 * @return >= 0 on success, a negative AVERROR code on failure.
4038 int avcodec_parameters_to_context(AVCodecContext *codec,
4039 const AVCodecParameters *par);
4042 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4043 * function the context has to be allocated with avcodec_alloc_context3().
4045 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4046 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4047 * retrieving a codec.
4049 * @warning This function is not thread safe!
4051 * @note Always call this function before using decoding routines (such as
4052 * @ref avcodec_receive_frame()).
4055 * avcodec_register_all();
4056 * av_dict_set(&opts, "b", "2.5M", 0);
4057 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4061 * context = avcodec_alloc_context3(codec);
4063 * if (avcodec_open2(context, codec, opts) < 0)
4067 * @param avctx The context to initialize.
4068 * @param codec The codec to open this context for. If a non-NULL codec has been
4069 * previously passed to avcodec_alloc_context3() or
4070 * for this context, then this parameter MUST be either NULL or
4071 * equal to the previously passed codec.
4072 * @param options A dictionary filled with AVCodecContext and codec-private options.
4073 * On return this object will be filled with options that were not found.
4075 * @return zero on success, a negative value on error
4076 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4077 * av_dict_set(), av_opt_find().
4079 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4082 * Close a given AVCodecContext and free all the data associated with it
4083 * (but not the AVCodecContext itself).
4085 * Calling this function on an AVCodecContext that hasn't been opened will free
4086 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4087 * codec. Subsequent calls will do nothing.
4089 * @note Do not use this function. Use avcodec_free_context() to destroy a
4090 * codec context (either open or closed). Opening and closing a codec context
4091 * multiple times is not supported anymore -- use multiple codec contexts
4094 int avcodec_close(AVCodecContext *avctx);
4097 * Free all allocated data in the given subtitle struct.
4099 * @param sub AVSubtitle to free.
4101 void avsubtitle_free(AVSubtitle *sub);
4108 * @addtogroup lavc_packet
4113 * Allocate an AVPacket and set its fields to default values. The resulting
4114 * struct must be freed using av_packet_free().
4116 * @return An AVPacket filled with default values or NULL on failure.
4118 * @note this only allocates the AVPacket itself, not the data buffers. Those
4119 * must be allocated through other means such as av_new_packet.
4121 * @see av_new_packet
4123 AVPacket *av_packet_alloc(void);
4126 * Create a new packet that references the same data as src.
4128 * This is a shortcut for av_packet_alloc()+av_packet_ref().
4130 * @return newly created AVPacket on success, NULL on error.
4132 * @see av_packet_alloc
4133 * @see av_packet_ref
4135 AVPacket *av_packet_clone(const AVPacket *src);
4138 * Free the packet, if the packet is reference counted, it will be
4139 * unreferenced first.
4141 * @param pkt packet to be freed. The pointer will be set to NULL.
4142 * @note passing NULL is a no-op.
4144 void av_packet_free(AVPacket **pkt);
4147 * Initialize optional fields of a packet with default values.
4149 * Note, this does not touch the data and size members, which have to be
4150 * initialized separately.
4154 void av_init_packet(AVPacket *pkt);
4157 * Allocate the payload of a packet and initialize its fields with
4161 * @param size wanted payload size
4162 * @return 0 if OK, AVERROR_xxx otherwise
4164 int av_new_packet(AVPacket *pkt, int size);
4167 * Reduce packet size, correctly zeroing padding
4170 * @param size new size
4172 void av_shrink_packet(AVPacket *pkt, int size);
4175 * Increase packet size, correctly zeroing padding
4178 * @param grow_by number of bytes by which to increase the size of the packet
4180 int av_grow_packet(AVPacket *pkt, int grow_by);
4183 * Initialize a reference-counted packet from av_malloc()ed data.
4185 * @param pkt packet to be initialized. This function will set the data, size,
4186 * buf and destruct fields, all others are left untouched.
4187 * @param data Data allocated by av_malloc() to be used as packet data. If this
4188 * function returns successfully, the data is owned by the underlying AVBuffer.
4189 * The caller may not access the data through other means.
4190 * @param size size of data in bytes, without the padding. I.e. the full buffer
4191 * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4193 * @return 0 on success, a negative AVERROR on error
4195 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
4197 #if FF_API_AVPACKET_OLD_API
4199 * @warning This is a hack - the packet memory allocation stuff is broken. The
4200 * packet is allocated if it was not really allocated.
4202 * @deprecated Use av_packet_ref
4204 attribute_deprecated
4205 int av_dup_packet(AVPacket *pkt);
4207 * Copy packet, including contents
4209 * @return 0 on success, negative AVERROR on fail
4211 * @deprecated Use av_packet_ref
4213 attribute_deprecated
4214 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4217 * Copy packet side data
4219 * @return 0 on success, negative AVERROR on fail
4221 * @deprecated Use av_packet_copy_props
4223 attribute_deprecated
4224 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4229 * @deprecated Use av_packet_unref
4231 * @param pkt packet to free
4233 attribute_deprecated
4234 void av_free_packet(AVPacket *pkt);
4237 * Allocate new information of a packet.
4240 * @param type side information type
4241 * @param size side information size
4242 * @return pointer to fresh allocated data or NULL otherwise
4244 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4248 * Wrap an existing array as a packet side data.
4251 * @param type side information type
4252 * @param data the side data array. It must be allocated with the av_malloc()
4253 * family of functions. The ownership of the data is transferred to
4255 * @param size side information size
4256 * @return a non-negative number on success, a negative AVERROR code on
4257 * failure. On failure, the packet is unchanged and the data remains
4258 * owned by the caller.
4260 int av_packet_add_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4261 uint8_t *data, size_t size);
4264 * Shrink the already allocated side data buffer
4267 * @param type side information type
4268 * @param size new side information size
4269 * @return 0 on success, < 0 on failure
4271 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4275 * Get side information from packet.
4278 * @param type desired side information type
4279 * @param size pointer for side information size to store (optional)
4280 * @return pointer to data if present or NULL otherwise
4282 uint8_t* av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type,
4285 #if FF_API_MERGE_SD_API
4286 attribute_deprecated
4287 int av_packet_merge_side_data(AVPacket *pkt);
4289 attribute_deprecated
4290 int av_packet_split_side_data(AVPacket *pkt);
4293 const char *av_packet_side_data_name(enum AVPacketSideDataType type);
4296 * Pack a dictionary for use in side_data.
4298 * @param dict The dictionary to pack.
4299 * @param size pointer to store the size of the returned data
4300 * @return pointer to data if successful, NULL otherwise
4302 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size);
4304 * Unpack a dictionary from side_data.
4306 * @param data data from side_data
4307 * @param size size of the data
4308 * @param dict the metadata storage dictionary
4309 * @return 0 on success, < 0 on failure
4311 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4315 * Convenience function to free all the side data stored.
4316 * All the other fields stay untouched.
4320 void av_packet_free_side_data(AVPacket *pkt);
4323 * Setup a new reference to the data described by a given packet
4325 * If src is reference-counted, setup dst as a new reference to the
4326 * buffer in src. Otherwise allocate a new buffer in dst and copy the
4327 * data from src into it.
4329 * All the other fields are copied from src.
4331 * @see av_packet_unref
4333 * @param dst Destination packet
4334 * @param src Source packet
4336 * @return 0 on success, a negative AVERROR on error.
4338 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4343 * Unreference the buffer referenced by the packet and reset the
4344 * remaining packet fields to their default values.
4346 * @param pkt The packet to be unreferenced.
4348 void av_packet_unref(AVPacket *pkt);
4351 * Move every field in src to dst and reset src.
4353 * @see av_packet_unref
4355 * @param src Source packet, will be reset
4356 * @param dst Destination packet
4358 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
4361 * Copy only "properties" fields from src to dst.
4363 * Properties for the purpose of this function are all the fields
4364 * beside those related to the packet data (buf, data, size)
4366 * @param dst Destination packet
4367 * @param src Source packet
4369 * @return 0 on success AVERROR on failure.
4371 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4374 * Convert valid timing fields (timestamps / durations) in a packet from one
4375 * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4378 * @param pkt packet on which the conversion will be performed
4379 * @param tb_src source timebase, in which the timing fields in pkt are
4381 * @param tb_dst destination timebase, to which the timing fields will be
4384 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4391 * @addtogroup lavc_decoding
4396 * Find a registered decoder with a matching codec ID.
4398 * @param id AVCodecID of the requested decoder
4399 * @return A decoder if one was found, NULL otherwise.
4401 AVCodec *avcodec_find_decoder(enum AVCodecID id);
4404 * Find a registered decoder with the specified name.
4406 * @param name name of the requested decoder
4407 * @return A decoder if one was found, NULL otherwise.
4409 AVCodec *avcodec_find_decoder_by_name(const char *name);
4412 * The default callback for AVCodecContext.get_buffer2(). It is made public so
4413 * it can be called by custom get_buffer2() implementations for decoders without
4414 * AV_CODEC_CAP_DR1 set.
4416 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
4419 * Modify width and height values so that they will result in a memory
4420 * buffer that is acceptable for the codec if you do not use any horizontal
4423 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4425 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
4428 * Modify width and height values so that they will result in a memory
4429 * buffer that is acceptable for the codec if you also ensure that all
4430 * line sizes are a multiple of the respective linesize_align[i].
4432 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4434 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
4435 int linesize_align[AV_NUM_DATA_POINTERS]);
4438 * Converts AVChromaLocation to swscale x/y chroma position.
4440 * The positions represent the chroma (0,0) position in a coordinates system
4441 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4443 * @param xpos horizontal chroma sample position
4444 * @param ypos vertical chroma sample position
4446 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4449 * Converts swscale x/y chroma position to AVChromaLocation.
4451 * The positions represent the chroma (0,0) position in a coordinates system
4452 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4454 * @param xpos horizontal chroma sample position
4455 * @param ypos vertical chroma sample position
4457 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4460 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4462 * Some decoders may support multiple frames in a single AVPacket. Such
4463 * decoders would then just decode the first frame and the return value would be
4464 * less than the packet size. In this case, avcodec_decode_audio4 has to be
4465 * called again with an AVPacket containing the remaining data in order to
4466 * decode the second frame, etc... Even if no frames are returned, the packet
4467 * needs to be fed to the decoder with remaining data until it is completely
4468 * consumed or an error occurs.
4470 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4471 * and output. This means that for some packets they will not immediately
4472 * produce decoded output and need to be flushed at the end of decoding to get
4473 * all the decoded data. Flushing is done by calling this function with packets
4474 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4475 * returning samples. It is safe to flush even those decoders that are not
4476 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4478 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4479 * larger than the actual read bytes because some optimized bitstream
4480 * readers read 32 or 64 bits at once and could read over the end.
4482 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4483 * before packets may be fed to the decoder.
4485 * @param avctx the codec context
4486 * @param[out] frame The AVFrame in which to store decoded audio samples.
4487 * The decoder will allocate a buffer for the decoded frame by
4488 * calling the AVCodecContext.get_buffer2() callback.
4489 * When AVCodecContext.refcounted_frames is set to 1, the frame is
4490 * reference counted and the returned reference belongs to the
4491 * caller. The caller must release the frame using av_frame_unref()
4492 * when the frame is no longer needed. The caller may safely write
4493 * to the frame if av_frame_is_writable() returns 1.
4494 * When AVCodecContext.refcounted_frames is set to 0, the returned
4495 * reference belongs to the decoder and is valid only until the
4496 * next call to this function or until closing or flushing the
4497 * decoder. The caller may not write to it.
4498 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4499 * non-zero. Note that this field being set to zero
4500 * does not mean that an error has occurred. For
4501 * decoders with AV_CODEC_CAP_DELAY set, no given decode
4502 * call is guaranteed to produce a frame.
4503 * @param[in] avpkt The input AVPacket containing the input buffer.
4504 * At least avpkt->data and avpkt->size should be set. Some
4505 * decoders might also require additional fields to be set.
4506 * @return A negative error code is returned if an error occurred during
4507 * decoding, otherwise the number of bytes consumed from the input
4508 * AVPacket is returned.
4510 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4512 attribute_deprecated
4513 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
4514 int *got_frame_ptr, const AVPacket *avpkt);
4517 * Decode the video frame of size avpkt->size from avpkt->data into picture.
4518 * Some decoders may support multiple frames in a single AVPacket, such
4519 * decoders would then just decode the first frame.
4521 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4522 * the actual read bytes because some optimized bitstream readers read 32 or 64
4523 * bits at once and could read over the end.
4525 * @warning The end of the input buffer buf should be set to 0 to ensure that
4526 * no overreading happens for damaged MPEG streams.
4528 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4529 * between input and output, these need to be fed with avpkt->data=NULL,
4530 * avpkt->size=0 at the end to return the remaining frames.
4532 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4533 * before packets may be fed to the decoder.
4535 * @param avctx the codec context
4536 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4537 * Use av_frame_alloc() to get an AVFrame. The codec will
4538 * allocate memory for the actual bitmap by calling the
4539 * AVCodecContext.get_buffer2() callback.
4540 * When AVCodecContext.refcounted_frames is set to 1, the frame is
4541 * reference counted and the returned reference belongs to the
4542 * caller. The caller must release the frame using av_frame_unref()
4543 * when the frame is no longer needed. The caller may safely write
4544 * to the frame if av_frame_is_writable() returns 1.
4545 * When AVCodecContext.refcounted_frames is set to 0, the returned
4546 * reference belongs to the decoder and is valid only until the
4547 * next call to this function or until closing or flushing the
4548 * decoder. The caller may not write to it.
4550 * @param[in] avpkt The input AVPacket containing the input buffer.
4551 * You can create such packet with av_init_packet() and by then setting
4552 * data and size, some decoders might in addition need other fields like
4553 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4555 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4556 * @return On error a negative value is returned, otherwise the number of bytes
4557 * used or zero if no frame could be decompressed.
4559 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4561 attribute_deprecated
4562 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4563 int *got_picture_ptr,
4564 const AVPacket *avpkt);
4567 * Decode a subtitle message.
4568 * Return a negative value on error, otherwise return the number of bytes used.
4569 * If no subtitle could be decompressed, got_sub_ptr is zero.
4570 * Otherwise, the subtitle is stored in *sub.
4571 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4572 * simplicity, because the performance difference is expect to be negligible
4573 * and reusing a get_buffer written for video codecs would probably perform badly
4574 * due to a potentially very different allocation pattern.
4576 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4577 * and output. This means that for some packets they will not immediately
4578 * produce decoded output and need to be flushed at the end of decoding to get
4579 * all the decoded data. Flushing is done by calling this function with packets
4580 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4581 * returning subtitles. It is safe to flush even those decoders that are not
4582 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4584 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4585 * before packets may be fed to the decoder.
4587 * @param avctx the codec context
4588 * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4589 * must be freed with avsubtitle_free if *got_sub_ptr is set.
4590 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4591 * @param[in] avpkt The input AVPacket containing the input buffer.
4593 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
4598 * Supply raw packet data as input to a decoder.
4600 * Internally, this call will copy relevant AVCodecContext fields, which can
4601 * influence decoding per-packet, and apply them when the packet is actually
4602 * decoded. (For example AVCodecContext.skip_frame, which might direct the
4603 * decoder to drop the frame contained by the packet sent with this function.)
4605 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4606 * larger than the actual read bytes because some optimized bitstream
4607 * readers read 32 or 64 bits at once and could read over the end.
4609 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4610 * on the same AVCodecContext. It will return unexpected results now
4611 * or in future libavcodec versions.
4613 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4614 * before packets may be fed to the decoder.
4616 * @param avctx codec context
4617 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4618 * frame, or several complete audio frames.
4619 * Ownership of the packet remains with the caller, and the
4620 * decoder will not write to the packet. The decoder may create
4621 * a reference to the packet data (or copy it if the packet is
4622 * not reference-counted).
4623 * Unlike with older APIs, the packet is always fully consumed,
4624 * and if it contains multiple frames (e.g. some audio codecs),
4625 * will require you to call avcodec_receive_frame() multiple
4626 * times afterwards before you can send a new packet.
4627 * It can be NULL (or an AVPacket with data set to NULL and
4628 * size set to 0); in this case, it is considered a flush
4629 * packet, which signals the end of the stream. Sending the
4630 * first flush packet will return success. Subsequent ones are
4631 * unnecessary and will return AVERROR_EOF. If the decoder
4632 * still has frames buffered, it will return them after sending
4635 * @return 0 on success, otherwise negative error code:
4636 * AVERROR(EAGAIN): input is not accepted in the current state - user
4637 * must read output with avcodec_receive_frame() (once
4638 * all output is read, the packet should be resent, and
4639 * the call will not fail with EAGAIN).
4640 * AVERROR_EOF: the decoder has been flushed, and no new packets can
4641 * be sent to it (also returned if more than 1 flush
4643 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4644 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4645 * other errors: legitimate decoding errors
4647 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4650 * Return decoded output data from a decoder.
4652 * @param avctx codec context
4653 * @param frame This will be set to a reference-counted video or audio
4654 * frame (depending on the decoder type) allocated by the
4655 * decoder. Note that the function will always call
4656 * av_frame_unref(frame) before doing anything else.
4659 * 0: success, a frame was returned
4660 * AVERROR(EAGAIN): output is not available in this state - user must try
4662 * AVERROR_EOF: the decoder has been fully flushed, and there will be
4663 * no more output frames
4664 * AVERROR(EINVAL): codec not opened, or it is an encoder
4665 * other negative values: legitimate decoding errors
4667 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
4670 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4671 * to retrieve buffered output packets.
4673 * @param avctx codec context
4674 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4675 * Ownership of the frame remains with the caller, and the
4676 * encoder will not write to the frame. The encoder may create
4677 * a reference to the frame data (or copy it if the frame is
4678 * not reference-counted).
4679 * It can be NULL, in which case it is considered a flush
4680 * packet. This signals the end of the stream. If the encoder
4681 * still has packets buffered, it will return them after this
4682 * call. Once flushing mode has been entered, additional flush
4683 * packets are ignored, and sending frames will return
4687 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4688 * can have any number of samples.
4689 * If it is not set, frame->nb_samples must be equal to
4690 * avctx->frame_size for all frames except the last.
4691 * The final frame may be smaller than avctx->frame_size.
4692 * @return 0 on success, otherwise negative error code:
4693 * AVERROR(EAGAIN): input is not accepted in the current state - user
4694 * must read output with avcodec_receive_packet() (once
4695 * all output is read, the packet should be resent, and
4696 * the call will not fail with EAGAIN).
4697 * AVERROR_EOF: the encoder has been flushed, and no new frames can
4699 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4700 * decoder, or requires flush
4701 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4702 * other errors: legitimate decoding errors
4704 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4707 * Read encoded data from the encoder.
4709 * @param avctx codec context
4710 * @param avpkt This will be set to a reference-counted packet allocated by the
4711 * encoder. Note that the function will always call
4712 * av_frame_unref(frame) before doing anything else.
4713 * @return 0 on success, otherwise negative error code:
4714 * AVERROR(EAGAIN): output is not available in the current state - user
4715 * must try to send input
4716 * AVERROR_EOF: the encoder has been fully flushed, and there will be
4717 * no more output packets
4718 * AVERROR(EINVAL): codec not opened, or it is an encoder
4719 * other errors: legitimate decoding errors
4721 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4724 * Create and return a AVHWFramesContext with values adequate for hardware
4725 * decoding. This is meant to get called from the get_format callback, and is
4726 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4727 * This API is for decoding with certain hardware acceleration modes/APIs only.
4729 * The returned AVHWFramesContext is not initialized. The caller must do this
4730 * with av_hwframe_ctx_init().
4732 * Calling this function is not a requirement, but makes it simpler to avoid
4733 * codec or hardware API specific details when manually allocating frames.
4735 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
4736 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
4737 * it unnecessary to call this function or having to care about
4738 * AVHWFramesContext initialization at all.
4740 * There are a number of requirements for calling this function:
4742 * - It must be called from get_format with the same avctx parameter that was
4743 * passed to get_format. Calling it outside of get_format is not allowed, and
4744 * can trigger undefined behavior.
4745 * - The function is not always supported (see description of return values).
4746 * Even if this function returns successfully, hwaccel initialization could
4747 * fail later. (The degree to which implementations check whether the stream
4748 * is actually supported varies. Some do this check only after the user's
4749 * get_format callback returns.)
4750 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
4751 * user decides to use a AVHWFramesContext prepared with this API function,
4752 * the user must return the same hw_pix_fmt from get_format.
4753 * - The device_ref passed to this function must support the given hw_pix_fmt.
4754 * - After calling this API function, it is the user's responsibility to
4755 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
4756 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
4757 * before returning from get_format (this is implied by the normal
4758 * AVCodecContext.hw_frames_ctx API rules).
4759 * - The AVHWFramesContext parameters may change every time time get_format is
4760 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
4761 * you are inherently required to go through this process again on every
4763 * - It is perfectly possible to call this function without actually using
4764 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
4765 * previously initialized AVHWFramesContext, and calling this API function
4766 * only to test whether the required frame parameters have changed.
4767 * - Fields that use dynamically allocated values of any kind must not be set
4768 * by the user unless setting them is explicitly allowed by the documentation.
4769 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
4770 * the new free callback must call the potentially set previous free callback.
4771 * This API call may set any dynamically allocated fields, including the free
4774 * The function will set at least the following fields on AVHWFramesContext
4775 * (potentially more, depending on hwaccel API):
4777 * - All fields set by av_hwframe_ctx_alloc().
4778 * - Set the format field to hw_pix_fmt.
4779 * - Set the sw_format field to the most suited and most versatile format. (An
4780 * implication is that this will prefer generic formats over opaque formats
4781 * with arbitrary restrictions, if possible.)
4782 * - Set the width/height fields to the coded frame size, rounded up to the
4783 * API-specific minimum alignment.
4784 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
4785 * field to the number of maximum reference surfaces possible with the codec,
4786 * plus 1 surface for the user to work (meaning the user can safely reference
4787 * at most 1 decoded surface at a time), plus additional buffering introduced
4788 * by frame threading. If the hwaccel does not require pre-allocation, the
4789 * field is left to 0, and the decoder will allocate new surfaces on demand
4791 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
4794 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
4795 * with basic frame parameters set.
4797 * The function is stateless, and does not change the AVCodecContext or the
4798 * device_ref AVHWDeviceContext.
4800 * @param avctx The context which is currently calling get_format, and which
4801 * implicitly contains all state needed for filling the returned
4802 * AVHWFramesContext properly.
4803 * @param device_ref A reference to the AVHWDeviceContext describing the device
4804 * which will be used by the hardware decoder.
4805 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
4806 * @param out_frames_ref On success, set to a reference to an _uninitialized_
4807 * AVHWFramesContext, created from the given device_ref.
4808 * Fields will be set to values required for decoding.
4809 * Not changed if an error is returned.
4810 * @return zero on success, a negative value on error. The following error codes
4811 * have special semantics:
4812 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
4813 * is always manual, or it is a decoder which does not
4814 * support setting AVCodecContext.hw_frames_ctx at all,
4815 * or it is a software format.
4816 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
4817 * this configuration, or the device_ref is not supported
4818 * for the hwaccel referenced by hw_pix_fmt.
4820 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
4821 AVBufferRef *device_ref,
4822 enum AVPixelFormat hw_pix_fmt,
4823 AVBufferRef **out_frames_ref);
4828 * @defgroup lavc_parsing Frame parsing
4832 enum AVPictureStructure {
4833 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
4834 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4835 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4836 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4839 typedef struct AVCodecParserContext {
4841 struct AVCodecParser *parser;
4842 int64_t frame_offset; /* offset of the current frame */
4843 int64_t cur_offset; /* current offset
4844 (incremented by each av_parser_parse()) */
4845 int64_t next_frame_offset; /* offset of the next frame */
4847 int pict_type; /* XXX: Put it back in AVCodecContext. */
4849 * This field is used for proper frame duration computation in lavf.
4850 * It signals, how much longer the frame duration of the current frame
4851 * is compared to normal frame duration.
4853 * frame_duration = (1 + repeat_pict) * time_base
4855 * It is used by codecs like H.264 to display telecined material.
4857 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4858 int64_t pts; /* pts of the current frame */
4859 int64_t dts; /* dts of the current frame */
4864 int fetch_timestamp;
4866 #define AV_PARSER_PTS_NB 4
4867 int cur_frame_start_index;
4868 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
4869 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
4870 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
4873 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4874 #define PARSER_FLAG_ONCE 0x0002
4875 /// Set if the parser has a valid file offset
4876 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4877 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4879 int64_t offset; ///< byte offset from starting packet start
4880 int64_t cur_frame_end[AV_PARSER_PTS_NB];
4883 * Set by parser to 1 for key frames and 0 for non-key frames.
4884 * It is initialized to -1, so if the parser doesn't set this flag,
4885 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4890 #if FF_API_CONVERGENCE_DURATION
4892 * @deprecated unused
4894 attribute_deprecated
4895 int64_t convergence_duration;
4898 // Timestamp generation support:
4900 * Synchronization point for start of timestamp generation.
4902 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4905 * For example, this corresponds to presence of H.264 buffering period
4911 * Offset of the current timestamp against last timestamp sync point in
4912 * units of AVCodecContext.time_base.
4914 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4915 * contain a valid timestamp offset.
4917 * Note that the timestamp of sync point has usually a nonzero
4918 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4919 * the next frame after timestamp sync point will be usually 1.
4921 * For example, this corresponds to H.264 cpb_removal_delay.
4923 int dts_ref_dts_delta;
4926 * Presentation delay of current frame in units of AVCodecContext.time_base.
4928 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4929 * contain valid non-negative timestamp delta (presentation time of a frame
4930 * must not lie in the past).
4932 * This delay represents the difference between decoding and presentation
4933 * time of the frame.
4935 * For example, this corresponds to H.264 dpb_output_delay.
4940 * Position of the packet in file.
4942 * Analogous to cur_frame_pts/dts
4944 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4947 * Byte position of currently parsed frame in stream.
4952 * Previous frame byte position.
4957 * Duration of the current frame.
4958 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4959 * For all other types, this is in units of AVCodecContext.time_base.
4963 enum AVFieldOrder field_order;
4966 * Indicate whether a picture is coded as a frame, top field or bottom field.
4968 * For example, H.264 field_pic_flag equal to 0 corresponds to
4969 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4970 * equal to 1 and bottom_field_flag equal to 0 corresponds to
4971 * AV_PICTURE_STRUCTURE_TOP_FIELD.
4973 enum AVPictureStructure picture_structure;
4976 * Picture number incremented in presentation or output order.
4977 * This field may be reinitialized at the first picture of a new sequence.
4979 * For example, this corresponds to H.264 PicOrderCnt.
4981 int output_picture_number;
4984 * Dimensions of the decoded video intended for presentation.
4990 * Dimensions of the coded video.
4996 * The format of the coded data, corresponds to enum AVPixelFormat for video
4997 * and for enum AVSampleFormat for audio.
4999 * Note that a decoder can have considerable freedom in how exactly it
5000 * decodes the data, so the format reported here might be different from the
5001 * one returned by a decoder.
5004 } AVCodecParserContext;
5006 typedef struct AVCodecParser {
5007 int codec_ids[5]; /* several codec IDs are permitted */
5009 int (*parser_init)(AVCodecParserContext *s);
5010 /* This callback never returns an error, a negative value means that
5011 * the frame start was in a previous packet. */
5012 int (*parser_parse)(AVCodecParserContext *s,
5013 AVCodecContext *avctx,
5014 const uint8_t **poutbuf, int *poutbuf_size,
5015 const uint8_t *buf, int buf_size);
5016 void (*parser_close)(AVCodecParserContext *s);
5017 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5018 struct AVCodecParser *next;
5021 AVCodecParser *av_parser_next(const AVCodecParser *c);
5023 void av_register_codec_parser(AVCodecParser *parser);
5024 AVCodecParserContext *av_parser_init(int codec_id);
5029 * @param s parser context.
5030 * @param avctx codec context.
5031 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5032 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5033 * @param buf input buffer.
5034 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5035 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5036 To signal EOF, this should be 0 (so that the last frame
5038 * @param pts input presentation timestamp.
5039 * @param dts input decoding timestamp.
5040 * @param pos input byte position in stream.
5041 * @return the number of bytes of the input bitstream used.
5046 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5053 * decode_frame(data, size);
5057 int av_parser_parse2(AVCodecParserContext *s,
5058 AVCodecContext *avctx,
5059 uint8_t **poutbuf, int *poutbuf_size,
5060 const uint8_t *buf, int buf_size,
5061 int64_t pts, int64_t dts,
5065 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5066 * @deprecated use AVBitStreamFilter
5068 int av_parser_change(AVCodecParserContext *s,
5069 AVCodecContext *avctx,
5070 uint8_t **poutbuf, int *poutbuf_size,
5071 const uint8_t *buf, int buf_size, int keyframe);
5072 void av_parser_close(AVCodecParserContext *s);
5080 * @addtogroup lavc_encoding
5085 * Find a registered encoder with a matching codec ID.
5087 * @param id AVCodecID of the requested encoder
5088 * @return An encoder if one was found, NULL otherwise.
5090 AVCodec *avcodec_find_encoder(enum AVCodecID id);
5093 * Find a registered encoder with the specified name.
5095 * @param name name of the requested encoder
5096 * @return An encoder if one was found, NULL otherwise.
5098 AVCodec *avcodec_find_encoder_by_name(const char *name);
5101 * Encode a frame of audio.
5103 * Takes input samples from frame and writes the next output packet, if
5104 * available, to avpkt. The output packet does not necessarily contain data for
5105 * the most recent frame, as encoders can delay, split, and combine input frames
5106 * internally as needed.
5108 * @param avctx codec context
5109 * @param avpkt output AVPacket.
5110 * The user can supply an output buffer by setting
5111 * avpkt->data and avpkt->size prior to calling the
5112 * function, but if the size of the user-provided data is not
5113 * large enough, encoding will fail. If avpkt->data and
5114 * avpkt->size are set, avpkt->destruct must also be set. All
5115 * other AVPacket fields will be reset by the encoder using
5116 * av_init_packet(). If avpkt->data is NULL, the encoder will
5117 * allocate it. The encoder will set avpkt->size to the size
5118 * of the output packet.
5120 * If this function fails or produces no output, avpkt will be
5121 * freed using av_packet_unref().
5122 * @param[in] frame AVFrame containing the raw audio data to be encoded.
5123 * May be NULL when flushing an encoder that has the
5124 * AV_CODEC_CAP_DELAY capability set.
5125 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5126 * can have any number of samples.
5127 * If it is not set, frame->nb_samples must be equal to
5128 * avctx->frame_size for all frames except the last.
5129 * The final frame may be smaller than avctx->frame_size.
5130 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5131 * output packet is non-empty, and to 0 if it is
5132 * empty. If the function returns an error, the
5133 * packet can be assumed to be invalid, and the
5134 * value of got_packet_ptr is undefined and should
5136 * @return 0 on success, negative error code on failure
5138 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5140 attribute_deprecated
5141 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5142 const AVFrame *frame, int *got_packet_ptr);
5145 * Encode a frame of video.
5147 * Takes input raw video data from frame and writes the next output packet, if
5148 * available, to avpkt. The output packet does not necessarily contain data for
5149 * the most recent frame, as encoders can delay and reorder input frames
5150 * internally as needed.
5152 * @param avctx codec context
5153 * @param avpkt output AVPacket.
5154 * The user can supply an output buffer by setting
5155 * avpkt->data and avpkt->size prior to calling the
5156 * function, but if the size of the user-provided data is not
5157 * large enough, encoding will fail. All other AVPacket fields
5158 * will be reset by the encoder using av_init_packet(). If
5159 * avpkt->data is NULL, the encoder will allocate it.
5160 * The encoder will set avpkt->size to the size of the
5161 * output packet. The returned data (if any) belongs to the
5162 * caller, he is responsible for freeing it.
5164 * If this function fails or produces no output, avpkt will be
5165 * freed using av_packet_unref().
5166 * @param[in] frame AVFrame containing the raw video data to be encoded.
5167 * May be NULL when flushing an encoder that has the
5168 * AV_CODEC_CAP_DELAY capability set.
5169 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5170 * output packet is non-empty, and to 0 if it is
5171 * empty. If the function returns an error, the
5172 * packet can be assumed to be invalid, and the
5173 * value of got_packet_ptr is undefined and should
5175 * @return 0 on success, negative error code on failure
5177 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5179 attribute_deprecated
5180 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
5181 const AVFrame *frame, int *got_packet_ptr);
5183 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
5184 const AVSubtitle *sub);
5191 #if FF_API_AVPICTURE
5193 * @addtogroup lavc_picture
5198 * @deprecated unused
5200 attribute_deprecated
5201 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
5204 * @deprecated unused
5206 attribute_deprecated
5207 void avpicture_free(AVPicture *picture);
5210 * @deprecated use av_image_fill_arrays() instead.
5212 attribute_deprecated
5213 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
5214 enum AVPixelFormat pix_fmt, int width, int height);
5217 * @deprecated use av_image_copy_to_buffer() instead.
5219 attribute_deprecated
5220 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
5221 int width, int height,
5222 unsigned char *dest, int dest_size);
5225 * @deprecated use av_image_get_buffer_size() instead.
5227 attribute_deprecated
5228 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
5231 * @deprecated av_image_copy() instead.
5233 attribute_deprecated
5234 void av_picture_copy(AVPicture *dst, const AVPicture *src,
5235 enum AVPixelFormat pix_fmt, int width, int height);
5238 * @deprecated unused
5240 attribute_deprecated
5241 int av_picture_crop(AVPicture *dst, const AVPicture *src,
5242 enum AVPixelFormat pix_fmt, int top_band, int left_band);
5245 * @deprecated unused
5247 attribute_deprecated
5248 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
5249 int padtop, int padbottom, int padleft, int padright, int *color);
5257 * @defgroup lavc_misc Utility functions
5260 * Miscellaneous utility functions related to both encoding and decoding
5266 * @defgroup lavc_misc_pixfmt Pixel formats
5268 * Functions for working with pixel formats.
5272 #if FF_API_GETCHROMA
5274 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
5277 attribute_deprecated
5278 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
5282 * Return a value representing the fourCC code associated to the
5283 * pixel format pix_fmt, or 0 if no associated fourCC code can be
5286 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
5289 * @deprecated see av_get_pix_fmt_loss()
5291 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
5295 * Find the best pixel format to convert to given a certain source pixel
5296 * format. When converting from one pixel format to another, information loss
5297 * may occur. For example, when converting from RGB24 to GRAY, the color
5298 * information will be lost. Similarly, other losses occur when converting from
5299 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
5300 * the given pixel formats should be used to suffer the least amount of loss.
5301 * The pixel formats from which it chooses one, are determined by the
5302 * pix_fmt_list parameter.
5305 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
5306 * @param[in] src_pix_fmt source pixel format
5307 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
5308 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
5309 * @return The best pixel format to convert to or -1 if none was found.
5311 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
5312 enum AVPixelFormat src_pix_fmt,
5313 int has_alpha, int *loss_ptr);
5316 * @deprecated see av_find_best_pix_fmt_of_2()
5318 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
5319 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
5321 attribute_deprecated
5322 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
5323 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
5325 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
5331 #if FF_API_TAG_STRING
5333 * Put a string representing the codec tag codec_tag in buf.
5335 * @param buf buffer to place codec tag in
5336 * @param buf_size size in bytes of buf
5337 * @param codec_tag codec tag to assign
5338 * @return the length of the string that would have been generated if
5339 * enough space had been available, excluding the trailing null
5341 * @deprecated see av_fourcc_make_string() and av_fourcc2str().
5343 attribute_deprecated
5344 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
5347 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
5350 * Return a name for the specified profile, if available.
5352 * @param codec the codec that is searched for the given profile
5353 * @param profile the profile value for which a name is requested
5354 * @return A name for the profile if found, NULL otherwise.
5356 const char *av_get_profile_name(const AVCodec *codec, int profile);
5359 * Return a name for the specified profile, if available.
5361 * @param codec_id the ID of the codec to which the requested profile belongs
5362 * @param profile the profile value for which a name is requested
5363 * @return A name for the profile if found, NULL otherwise.
5365 * @note unlike av_get_profile_name(), which searches a list of profiles
5366 * supported by a specific decoder or encoder implementation, this
5367 * function searches the list of profiles from the AVCodecDescriptor
5369 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
5371 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
5372 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
5373 //FIXME func typedef
5376 * Fill AVFrame audio data and linesize pointers.
5378 * The buffer buf must be a preallocated buffer with a size big enough
5379 * to contain the specified samples amount. The filled AVFrame data
5380 * pointers will point to this buffer.
5382 * AVFrame extended_data channel pointers are allocated if necessary for
5385 * @param frame the AVFrame
5386 * frame->nb_samples must be set prior to calling the
5387 * function. This function fills in frame->data,
5388 * frame->extended_data, frame->linesize[0].
5389 * @param nb_channels channel count
5390 * @param sample_fmt sample format
5391 * @param buf buffer to use for frame data
5392 * @param buf_size size of buffer
5393 * @param align plane size sample alignment (0 = default)
5394 * @return >=0 on success, negative error code on failure
5395 * @todo return the size in bytes required to store the samples in
5396 * case of success, at the next libavutil bump
5398 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
5399 enum AVSampleFormat sample_fmt, const uint8_t *buf,
5400 int buf_size, int align);
5403 * Reset the internal decoder state / flush internal buffers. Should be called
5404 * e.g. when seeking or when switching to a different stream.
5406 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
5407 * this invalidates the frames previously returned from the decoder. When
5408 * refcounted frames are used, the decoder just releases any references it might
5409 * keep internally, but the caller's reference remains valid.
5411 void avcodec_flush_buffers(AVCodecContext *avctx);
5414 * Return codec bits per sample.
5416 * @param[in] codec_id the codec
5417 * @return Number of bits per sample or zero if unknown for the given codec.
5419 int av_get_bits_per_sample(enum AVCodecID codec_id);
5422 * Return the PCM codec associated with a sample format.
5423 * @param be endianness, 0 for little, 1 for big,
5424 * -1 (or anything else) for native
5425 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
5427 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
5430 * Return codec bits per sample.
5431 * Only return non-zero if the bits per sample is exactly correct, not an
5434 * @param[in] codec_id the codec
5435 * @return Number of bits per sample or zero if unknown for the given codec.
5437 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
5440 * Return audio frame duration.
5442 * @param avctx codec context
5443 * @param frame_bytes size of the frame, or 0 if unknown
5444 * @return frame duration, in samples, if known. 0 if not able to
5447 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
5450 * This function is the same as av_get_audio_frame_duration(), except it works
5451 * with AVCodecParameters instead of an AVCodecContext.
5453 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
5456 typedef struct AVBitStreamFilterContext {
5458 const struct AVBitStreamFilter *filter;
5459 AVCodecParserContext *parser;
5460 struct AVBitStreamFilterContext *next;
5462 * Internal default arguments, used if NULL is passed to av_bitstream_filter_filter().
5463 * Not for access by library users.
5466 } AVBitStreamFilterContext;
5469 typedef struct AVBSFInternal AVBSFInternal;
5472 * The bitstream filter state.
5474 * This struct must be allocated with av_bsf_alloc() and freed with
5477 * The fields in the struct will only be changed (by the caller or by the
5478 * filter) as described in their documentation, and are to be considered
5479 * immutable otherwise.
5481 typedef struct AVBSFContext {
5483 * A class for logging and AVOptions
5485 const AVClass *av_class;
5488 * The bitstream filter this context is an instance of.
5490 const struct AVBitStreamFilter *filter;
5493 * Opaque libavcodec internal data. Must not be touched by the caller in any
5496 AVBSFInternal *internal;
5499 * Opaque filter-specific private data. If filter->priv_class is non-NULL,
5500 * this is an AVOptions-enabled struct.
5505 * Parameters of the input stream. This field is allocated in
5506 * av_bsf_alloc(), it needs to be filled by the caller before
5509 AVCodecParameters *par_in;
5512 * Parameters of the output stream. This field is allocated in
5513 * av_bsf_alloc(), it is set by the filter in av_bsf_init().
5515 AVCodecParameters *par_out;
5518 * The timebase used for the timestamps of the input packets. Set by the
5519 * caller before av_bsf_init().
5521 AVRational time_base_in;
5524 * The timebase used for the timestamps of the output packets. Set by the
5525 * filter in av_bsf_init().
5527 AVRational time_base_out;
5530 typedef struct AVBitStreamFilter {
5534 * A list of codec ids supported by the filter, terminated by
5536 * May be NULL, in that case the bitstream filter works with any codec id.
5538 const enum AVCodecID *codec_ids;
5541 * A class for the private data, used to declare bitstream filter private
5542 * AVOptions. This field is NULL for bitstream filters that do not declare
5545 * If this field is non-NULL, the first member of the filter private data
5546 * must be a pointer to AVClass, which will be set by libavcodec generic
5547 * code to this class.
5549 const AVClass *priv_class;
5551 /*****************************************************************
5552 * No fields below this line are part of the public API. They
5553 * may not be used outside of libavcodec and can be changed and
5555 * New public fields should be added right above.
5556 *****************************************************************
5560 int (*init)(AVBSFContext *ctx);
5561 int (*filter)(AVBSFContext *ctx, AVPacket *pkt);
5562 void (*close)(AVBSFContext *ctx);
5563 } AVBitStreamFilter;
5567 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5568 * is deprecated. Use the new bitstream filtering API (using AVBSFContext).
5570 attribute_deprecated
5571 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
5573 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5574 * is deprecated. Use av_bsf_get_by_name(), av_bsf_alloc(), and av_bsf_init()
5575 * from the new bitstream filtering API (using AVBSFContext).
5577 attribute_deprecated
5578 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
5580 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5581 * is deprecated. Use av_bsf_send_packet() and av_bsf_receive_packet() from the
5582 * new bitstream filtering API (using AVBSFContext).
5584 attribute_deprecated
5585 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
5586 AVCodecContext *avctx, const char *args,
5587 uint8_t **poutbuf, int *poutbuf_size,
5588 const uint8_t *buf, int buf_size, int keyframe);
5590 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5591 * is deprecated. Use av_bsf_free() from the new bitstream filtering API (using
5594 attribute_deprecated
5595 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
5597 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5598 * is deprecated. Use av_bsf_next() from the new bitstream filtering API (using
5601 attribute_deprecated
5602 const AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
5606 * @return a bitstream filter with the specified name or NULL if no such
5607 * bitstream filter exists.
5609 const AVBitStreamFilter *av_bsf_get_by_name(const char *name);
5612 * Iterate over all registered bitstream filters.
5614 * @param opaque a pointer where libavcodec will store the iteration state. Must
5615 * point to NULL to start the iteration.
5617 * @return the next registered bitstream filter or NULL when the iteration is
5620 const AVBitStreamFilter *av_bsf_next(void **opaque);
5623 * Allocate a context for a given bitstream filter. The caller must fill in the
5624 * context parameters as described in the documentation and then call
5625 * av_bsf_init() before sending any data to the filter.
5627 * @param filter the filter for which to allocate an instance.
5628 * @param ctx a pointer into which the pointer to the newly-allocated context
5629 * will be written. It must be freed with av_bsf_free() after the
5630 * filtering is done.
5632 * @return 0 on success, a negative AVERROR code on failure
5634 int av_bsf_alloc(const AVBitStreamFilter *filter, AVBSFContext **ctx);
5637 * Prepare the filter for use, after all the parameters and options have been
5640 int av_bsf_init(AVBSFContext *ctx);
5643 * Submit a packet for filtering.
5645 * After sending each packet, the filter must be completely drained by calling
5646 * av_bsf_receive_packet() repeatedly until it returns AVERROR(EAGAIN) or
5649 * @param pkt the packet to filter. The bitstream filter will take ownership of
5650 * the packet and reset the contents of pkt. pkt is not touched if an error occurs.
5651 * This parameter may be NULL, which signals the end of the stream (i.e. no more
5652 * packets will be sent). That will cause the filter to output any packets it
5653 * may have buffered internally.
5655 * @return 0 on success, a negative AVERROR on error.
5657 int av_bsf_send_packet(AVBSFContext *ctx, AVPacket *pkt);
5660 * Retrieve a filtered packet.
5662 * @param[out] pkt this struct will be filled with the contents of the filtered
5663 * packet. It is owned by the caller and must be freed using
5664 * av_packet_unref() when it is no longer needed.
5665 * This parameter should be "clean" (i.e. freshly allocated
5666 * with av_packet_alloc() or unreffed with av_packet_unref())
5667 * when this function is called. If this function returns
5668 * successfully, the contents of pkt will be completely
5669 * overwritten by the returned data. On failure, pkt is not
5672 * @return 0 on success. AVERROR(EAGAIN) if more packets need to be sent to the
5673 * filter (using av_bsf_send_packet()) to get more output. AVERROR_EOF if there
5674 * will be no further output from the filter. Another negative AVERROR value if
5677 * @note one input packet may result in several output packets, so after sending
5678 * a packet with av_bsf_send_packet(), this function needs to be called
5679 * repeatedly until it stops returning 0. It is also possible for a filter to
5680 * output fewer packets than were sent to it, so this function may return
5681 * AVERROR(EAGAIN) immediately after a successful av_bsf_send_packet() call.
5683 int av_bsf_receive_packet(AVBSFContext *ctx, AVPacket *pkt);
5686 * Free a bitstream filter context and everything associated with it; write NULL
5687 * into the supplied pointer.
5689 void av_bsf_free(AVBSFContext **ctx);
5692 * Get the AVClass for AVBSFContext. It can be used in combination with
5693 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
5695 * @see av_opt_find().
5697 const AVClass *av_bsf_get_class(void);
5700 * Structure for chain/list of bitstream filters.
5701 * Empty list can be allocated by av_bsf_list_alloc().
5703 typedef struct AVBSFList AVBSFList;
5706 * Allocate empty list of bitstream filters.
5707 * The list must be later freed by av_bsf_list_free()
5708 * or finalized by av_bsf_list_finalize().
5710 * @return Pointer to @ref AVBSFList on success, NULL in case of failure
5712 AVBSFList *av_bsf_list_alloc(void);
5715 * Free list of bitstream filters.
5717 * @param lst Pointer to pointer returned by av_bsf_list_alloc()
5719 void av_bsf_list_free(AVBSFList **lst);
5722 * Append bitstream filter to the list of bitstream filters.
5724 * @param lst List to append to
5725 * @param bsf Filter context to be appended
5727 * @return >=0 on success, negative AVERROR in case of failure
5729 int av_bsf_list_append(AVBSFList *lst, AVBSFContext *bsf);
5732 * Construct new bitstream filter context given it's name and options
5733 * and append it to the list of bitstream filters.
5735 * @param lst List to append to
5736 * @param bsf_name Name of the bitstream filter
5737 * @param options Options for the bitstream filter, can be set to NULL
5739 * @return >=0 on success, negative AVERROR in case of failure
5741 int av_bsf_list_append2(AVBSFList *lst, const char * bsf_name, AVDictionary **options);
5743 * Finalize list of bitstream filters.
5745 * This function will transform @ref AVBSFList to single @ref AVBSFContext,
5746 * so the whole chain of bitstream filters can be treated as single filter
5747 * freshly allocated by av_bsf_alloc().
5748 * If the call is successful, @ref AVBSFList structure is freed and lst
5749 * will be set to NULL. In case of failure, caller is responsible for
5750 * freeing the structure by av_bsf_list_free()
5752 * @param lst Filter list structure to be transformed
5753 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
5754 * representing the chain of bitstream filters
5756 * @return >=0 on success, negative AVERROR in case of failure
5758 int av_bsf_list_finalize(AVBSFList **lst, AVBSFContext **bsf);
5761 * Parse string describing list of bitstream filters and create single
5762 * @ref AVBSFContext describing the whole chain of bitstream filters.
5763 * Resulting @ref AVBSFContext can be treated as any other @ref AVBSFContext freshly
5764 * allocated by av_bsf_alloc().
5766 * @param str String describing chain of bitstream filters in format
5767 * `bsf1[=opt1=val1:opt2=val2][,bsf2]`
5768 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
5769 * representing the chain of bitstream filters
5771 * @return >=0 on success, negative AVERROR in case of failure
5773 int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf);
5776 * Get null/pass-through bitstream filter.
5778 * @param[out] bsf Pointer to be set to new instance of pass-through bitstream filter
5782 int av_bsf_get_null_filter(AVBSFContext **bsf);
5787 * Same behaviour av_fast_malloc but the buffer has additional
5788 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
5790 * In addition the whole buffer will initially and after resizes
5791 * be 0-initialized so that no uninitialized data will ever appear.
5793 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
5796 * Same behaviour av_fast_padded_malloc except that buffer will always
5797 * be 0-initialized after call.
5799 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
5802 * Encode extradata length to a buffer. Used by xiph codecs.
5804 * @param s buffer to write to; must be at least (v/255+1) bytes long
5805 * @param v size of extradata in bytes
5806 * @return number of bytes written to the buffer.
5808 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
5811 * Register the hardware accelerator hwaccel.
5813 void av_register_hwaccel(AVHWAccel *hwaccel);
5816 * If hwaccel is NULL, returns the first registered hardware accelerator,
5817 * if hwaccel is non-NULL, returns the next registered hardware accelerator
5818 * after hwaccel, or NULL if hwaccel is the last one.
5820 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
5824 * Lock operation used by lockmgr
5827 AV_LOCK_CREATE, ///< Create a mutex
5828 AV_LOCK_OBTAIN, ///< Lock the mutex
5829 AV_LOCK_RELEASE, ///< Unlock the mutex
5830 AV_LOCK_DESTROY, ///< Free mutex resources
5834 * Register a user provided lock manager supporting the operations
5835 * specified by AVLockOp. The "mutex" argument to the function points
5836 * to a (void *) where the lockmgr should store/get a pointer to a user
5837 * allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
5838 * value left by the last call for all other ops. If the lock manager is
5839 * unable to perform the op then it should leave the mutex in the same
5840 * state as when it was called and return a non-zero value. However,
5841 * when called with AV_LOCK_DESTROY the mutex will always be assumed to
5842 * have been successfully destroyed. If av_lockmgr_register succeeds
5843 * it will return a non-negative value, if it fails it will return a
5844 * negative value and destroy all mutex and unregister all callbacks.
5845 * av_lockmgr_register is not thread-safe, it must be called from a
5846 * single thread before any calls which make use of locking are used.
5848 * @param cb User defined callback. av_lockmgr_register invokes calls
5849 * to this callback and the previously registered callback.
5850 * The callback will be used to create more than one mutex
5851 * each of which must be backed by its own underlying locking
5852 * mechanism (i.e. do not use a single static object to
5853 * implement your lock manager). If cb is set to NULL the
5854 * lockmgr will be unregistered.
5856 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
5859 * Get the type of the given codec.
5861 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
5864 * Get the name of a codec.
5865 * @return a static string identifying the codec; never NULL
5867 const char *avcodec_get_name(enum AVCodecID id);
5870 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
5871 * with no corresponding avcodec_close()), 0 otherwise.
5873 int avcodec_is_open(AVCodecContext *s);
5876 * @return a non-zero number if codec is an encoder, zero otherwise
5878 int av_codec_is_encoder(const AVCodec *codec);
5881 * @return a non-zero number if codec is a decoder, zero otherwise
5883 int av_codec_is_decoder(const AVCodec *codec);
5886 * @return descriptor for given codec ID or NULL if no descriptor exists.
5888 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
5891 * Iterate over all codec descriptors known to libavcodec.
5893 * @param prev previous descriptor. NULL to get the first descriptor.
5895 * @return next descriptor or NULL after the last descriptor
5897 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
5900 * @return codec descriptor with the given name or NULL if no such descriptor
5903 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
5906 * Allocate a CPB properties structure and initialize its fields to default
5909 * @param size if non-NULL, the size of the allocated struct will be written
5910 * here. This is useful for embedding it in side data.
5912 * @return the newly allocated struct or NULL on failure
5914 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
5920 #endif /* AVCODEC_AVCODEC_H */