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/hwcontext.h"
40 #include "libavutil/log.h"
41 #include "libavutil/pixfmt.h"
42 #include "libavutil/rational.h"
47 * @defgroup libavc libavcodec
48 * Encoding/Decoding Library
52 * @defgroup lavc_decoding Decoding
56 * @defgroup lavc_encoding Encoding
60 * @defgroup lavc_codec Codecs
62 * @defgroup lavc_codec_native Native Codecs
65 * @defgroup lavc_codec_wrappers External library wrappers
68 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
72 * @defgroup lavc_internal Internal
80 * @defgroup lavc_encdec send/receive encoding and decoding API overview
83 * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
84 * avcodec_receive_packet() functions provide an encode/decode API, which
85 * decouples input and output.
87 * The API is very similar for encoding/decoding and audio/video, and works as
89 * - Set up and open the AVCodecContext as usual.
91 * - For decoding, call avcodec_send_packet() to give the decoder raw
92 * compressed data in an AVPacket.
93 * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
94 * containing uncompressed audio or video.
95 * In both cases, it is recommended that AVPackets and AVFrames are
96 * refcounted, or libavcodec might have to copy the input data. (libavformat
97 * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
98 * refcounted AVFrames.)
99 * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
100 * functions and process their output:
101 * - For decoding, call avcodec_receive_frame(). On success, it will return
102 * an AVFrame containing uncompressed audio or video data.
103 * - For encoding, call avcodec_receive_packet(). On success, it will return
104 * an AVPacket with a compressed frame.
105 * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
106 * AVERROR(EAGAIN) return value means that new input data is required to
107 * return new output. In this case, continue with sending input. For each
108 * input frame/packet, the codec will typically return 1 output frame/packet,
109 * but it can also be 0 or more than 1.
111 * At the beginning of decoding or encoding, the codec might accept multiple
112 * input frames/packets without returning a frame, until its internal buffers
113 * are filled. This situation is handled transparently if you follow the steps
116 * In theory, sending input can result in EAGAIN - this should happen only if
117 * not all output was received. You can use this to structure alternative decode
118 * or encode loops other than the one suggested above. For example, you could
119 * try sending new input on each iteration, and try to receive output if that
122 * End of stream situations. These require "flushing" (aka draining) the codec,
123 * as the codec might buffer multiple frames or packets internally for
124 * performance or out of necessity (consider B-frames).
125 * This is handled as follows:
126 * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
127 * or avcodec_send_frame() (encoding) functions. This will enter draining
129 * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
130 * (encoding) in a loop until AVERROR_EOF is returned. The functions will
131 * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
132 * - Before decoding can be resumed again, the codec has to be reset with
133 * avcodec_flush_buffers().
135 * Using the API as outlined above is highly recommended. But it is also
136 * possible to call functions outside of this rigid schema. For example, you can
137 * call avcodec_send_packet() repeatedly without calling
138 * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
139 * until the codec's internal buffer has been filled up (which is typically of
140 * size 1 per output frame, after initial input), and then reject input with
141 * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
142 * read at least some output.
144 * Not all codecs will follow a rigid and predictable dataflow; the only
145 * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
146 * one end implies that a receive/send call on the other end will succeed, or
147 * at least will not fail with AVERROR(EAGAIN). In general, no codec will
148 * permit unlimited buffering of input or output.
150 * This API replaces the following legacy functions:
151 * - avcodec_decode_video2() and avcodec_decode_audio4():
152 * Use avcodec_send_packet() to feed input to the decoder, then use
153 * avcodec_receive_frame() to receive decoded frames after each packet.
154 * Unlike with the old video decoding API, multiple frames might result from
155 * a packet. For audio, splitting the input packet into frames by partially
156 * decoding packets becomes transparent to the API user. You never need to
157 * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
158 * no data was read from the packet).
159 * Additionally, sending a flush/draining packet is required only once.
160 * - avcodec_encode_video2()/avcodec_encode_audio2():
161 * Use avcodec_send_frame() to feed input to the encoder, then use
162 * avcodec_receive_packet() to receive encoded packets.
163 * Providing user-allocated buffers for avcodec_receive_packet() is not
165 * - The new API does not handle subtitles yet.
167 * Mixing new and old function calls on the same AVCodecContext is not allowed,
168 * and will result in undefined behavior.
170 * Some codecs might require using the new API; using the old API will return
171 * an error when calling it. All codecs support the new API.
173 * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
174 * would be an invalid state, which could put the codec user into an endless
175 * loop. The API has no concept of time either: it cannot happen that trying to
176 * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
177 * later accepts the packet (with no other receive/flush API calls involved).
178 * The API is a strict state machine, and the passage of time is not supposed
179 * to influence it. Some timing-dependent behavior might still be deemed
180 * acceptable in certain cases. But it must never result in both send/receive
181 * returning EAGAIN at the same time at any point. It must also absolutely be
182 * avoided that the current state is "unstable" and can "flip-flop" between
183 * the send/receive APIs allowing progress. For example, it's not allowed that
184 * the codec randomly decides that it actually wants to consume a packet now
185 * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
186 * avcodec_send_packet() call.
191 * @defgroup lavc_core Core functions/structures.
194 * Basic definitions, functions for querying libavcodec capabilities,
195 * allocating core structures, etc.
201 * Identify the syntax and semantics of the bitstream.
202 * The principle is roughly:
203 * Two decoders with the same ID can decode the same streams.
204 * Two encoders with the same ID can encode compatible streams.
205 * There may be slight deviations from the principle due to implementation
208 * If you add a codec ID to this list, add it so that
209 * 1. no value of an existing codec ID changes (that would break ABI),
210 * 2. it is as close as possible to similar codecs
212 * After adding new codec IDs, do not forget to add an entry to the codec
213 * descriptor list and bump libavcodec minor version.
219 AV_CODEC_ID_MPEG1VIDEO,
220 AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
231 AV_CODEC_ID_RAWVIDEO,
232 AV_CODEC_ID_MSMPEG4V1,
233 AV_CODEC_ID_MSMPEG4V2,
234 AV_CODEC_ID_MSMPEG4V3,
257 AV_CODEC_ID_INTERPLAY_VIDEO,
264 AV_CODEC_ID_MSVIDEO1,
269 AV_CODEC_ID_TRUEMOTION1,
270 AV_CODEC_ID_VMDVIDEO,
295 AV_CODEC_ID_TRUEMOTION2,
301 AV_CODEC_ID_SMACKVIDEO,
306 AV_CODEC_ID_JPEG2000,
312 AV_CODEC_ID_DSICINVIDEO,
313 AV_CODEC_ID_TIERTEXSEQVIDEO,
321 AV_CODEC_ID_BETHSOFTVID,
333 AV_CODEC_ID_ESCAPE124,
337 AV_CODEC_ID_MOTIONPIXELS,
349 AV_CODEC_ID_FLASHSV2,
350 AV_CODEC_ID_CDGRAPHICS,
353 AV_CODEC_ID_BINKVIDEO,
354 AV_CODEC_ID_IFF_ILBM,
355 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
361 AV_CODEC_ID_A64_MULTI,
362 AV_CODEC_ID_A64_MULTI5,
365 AV_CODEC_ID_LAGARITH,
369 AV_CODEC_ID_WMV3IMAGE,
370 AV_CODEC_ID_VC1IMAGE,
372 AV_CODEC_ID_BMV_VIDEO,
379 AV_CODEC_ID_ZEROCODEC,
388 AV_CODEC_ID_ESCAPE130,
391 AV_CODEC_ID_HNM4_VIDEO,
393 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
395 AV_CODEC_ID_ALIAS_PIX,
396 AV_CODEC_ID_BRENDER_PIX,
397 AV_CODEC_ID_PAF_VIDEO,
410 AV_CODEC_ID_SCREENPRESSO,
413 AV_CODEC_ID_Y41P = 0x8000,
418 AV_CODEC_ID_TARGA_Y216,
430 AV_CODEC_ID_TRUEMOTION2RT,
432 AV_CODEC_ID_MAGICYUV,
433 AV_CODEC_ID_SHEERVIDEO,
440 AV_CODEC_ID_CLEARVIDEO,
443 AV_CODEC_ID_BITPACKED,
450 /* various PCM "codecs" */
451 AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
452 AV_CODEC_ID_PCM_S16LE = 0x10000,
453 AV_CODEC_ID_PCM_S16BE,
454 AV_CODEC_ID_PCM_U16LE,
455 AV_CODEC_ID_PCM_U16BE,
458 AV_CODEC_ID_PCM_MULAW,
459 AV_CODEC_ID_PCM_ALAW,
460 AV_CODEC_ID_PCM_S32LE,
461 AV_CODEC_ID_PCM_S32BE,
462 AV_CODEC_ID_PCM_U32LE,
463 AV_CODEC_ID_PCM_U32BE,
464 AV_CODEC_ID_PCM_S24LE,
465 AV_CODEC_ID_PCM_S24BE,
466 AV_CODEC_ID_PCM_U24LE,
467 AV_CODEC_ID_PCM_U24BE,
468 AV_CODEC_ID_PCM_S24DAUD,
469 AV_CODEC_ID_PCM_ZORK,
470 AV_CODEC_ID_PCM_S16LE_PLANAR,
472 AV_CODEC_ID_PCM_F32BE,
473 AV_CODEC_ID_PCM_F32LE,
474 AV_CODEC_ID_PCM_F64BE,
475 AV_CODEC_ID_PCM_F64LE,
476 AV_CODEC_ID_PCM_BLURAY,
479 AV_CODEC_ID_PCM_S8_PLANAR,
480 AV_CODEC_ID_PCM_S24LE_PLANAR,
481 AV_CODEC_ID_PCM_S32LE_PLANAR,
482 AV_CODEC_ID_PCM_S16BE_PLANAR,
484 AV_CODEC_ID_PCM_S64LE = 0x10800,
485 AV_CODEC_ID_PCM_S64BE,
486 AV_CODEC_ID_PCM_F16LE,
487 AV_CODEC_ID_PCM_F24LE,
489 /* various ADPCM codecs */
490 AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
491 AV_CODEC_ID_ADPCM_IMA_WAV,
492 AV_CODEC_ID_ADPCM_IMA_DK3,
493 AV_CODEC_ID_ADPCM_IMA_DK4,
494 AV_CODEC_ID_ADPCM_IMA_WS,
495 AV_CODEC_ID_ADPCM_IMA_SMJPEG,
496 AV_CODEC_ID_ADPCM_MS,
497 AV_CODEC_ID_ADPCM_4XM,
498 AV_CODEC_ID_ADPCM_XA,
499 AV_CODEC_ID_ADPCM_ADX,
500 AV_CODEC_ID_ADPCM_EA,
501 AV_CODEC_ID_ADPCM_G726,
502 AV_CODEC_ID_ADPCM_CT,
503 AV_CODEC_ID_ADPCM_SWF,
504 AV_CODEC_ID_ADPCM_YAMAHA,
505 AV_CODEC_ID_ADPCM_SBPRO_4,
506 AV_CODEC_ID_ADPCM_SBPRO_3,
507 AV_CODEC_ID_ADPCM_SBPRO_2,
508 AV_CODEC_ID_ADPCM_THP,
509 AV_CODEC_ID_ADPCM_IMA_AMV,
510 AV_CODEC_ID_ADPCM_EA_R1,
511 AV_CODEC_ID_ADPCM_EA_R3,
512 AV_CODEC_ID_ADPCM_EA_R2,
513 AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
514 AV_CODEC_ID_ADPCM_IMA_EA_EACS,
515 AV_CODEC_ID_ADPCM_EA_XAS,
516 AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
517 AV_CODEC_ID_ADPCM_IMA_ISS,
518 AV_CODEC_ID_ADPCM_G722,
519 AV_CODEC_ID_ADPCM_IMA_APC,
520 AV_CODEC_ID_ADPCM_VIMA,
522 AV_CODEC_ID_ADPCM_AFC = 0x11800,
523 AV_CODEC_ID_ADPCM_IMA_OKI,
524 AV_CODEC_ID_ADPCM_DTK,
525 AV_CODEC_ID_ADPCM_IMA_RAD,
526 AV_CODEC_ID_ADPCM_G726LE,
527 AV_CODEC_ID_ADPCM_THP_LE,
528 AV_CODEC_ID_ADPCM_PSX,
529 AV_CODEC_ID_ADPCM_AICA,
530 AV_CODEC_ID_ADPCM_IMA_DAT4,
531 AV_CODEC_ID_ADPCM_MTAF,
534 AV_CODEC_ID_AMR_NB = 0x12000,
537 /* RealAudio codecs*/
538 AV_CODEC_ID_RA_144 = 0x13000,
541 /* various DPCM codecs */
542 AV_CODEC_ID_ROQ_DPCM = 0x14000,
543 AV_CODEC_ID_INTERPLAY_DPCM,
544 AV_CODEC_ID_XAN_DPCM,
545 AV_CODEC_ID_SOL_DPCM,
547 AV_CODEC_ID_SDX2_DPCM = 0x14800,
548 AV_CODEC_ID_GREMLIN_DPCM,
551 AV_CODEC_ID_MP2 = 0x15000,
552 AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
562 AV_CODEC_ID_VMDAUDIO,
568 AV_CODEC_ID_WESTWOOD_SND1,
569 AV_CODEC_ID_GSM, ///< as in Berlin toast format
572 AV_CODEC_ID_TRUESPEECH,
574 AV_CODEC_ID_SMACKAUDIO,
577 AV_CODEC_ID_DSICINAUDIO,
579 AV_CODEC_ID_MUSEPACK7,
581 AV_CODEC_ID_GSM_MS, /* as found in WAV */
584 AV_CODEC_ID_NELLYMOSER,
585 AV_CODEC_ID_MUSEPACK8,
587 AV_CODEC_ID_WMAVOICE,
589 AV_CODEC_ID_WMALOSSLESS,
598 AV_CODEC_ID_BINKAUDIO_RDFT,
599 AV_CODEC_ID_BINKAUDIO_DCT,
600 AV_CODEC_ID_AAC_LATM,
605 AV_CODEC_ID_8SVX_EXP,
606 AV_CODEC_ID_8SVX_FIB,
607 AV_CODEC_ID_BMV_AUDIO,
612 AV_CODEC_ID_COMFORT_NOISE,
614 AV_CODEC_ID_METASOUND,
615 AV_CODEC_ID_PAF_AUDIO,
619 AV_CODEC_ID_FFWAVESYNTH = 0x15800,
621 AV_CODEC_ID_SONIC_LS,
624 AV_CODEC_ID_DSD_LSBF,
625 AV_CODEC_ID_DSD_MSBF,
626 AV_CODEC_ID_DSD_LSBF_PLANAR,
627 AV_CODEC_ID_DSD_MSBF_PLANAR,
629 AV_CODEC_ID_INTERPLAY_ACM,
633 AV_CODEC_ID_ATRAC3AL,
634 AV_CODEC_ID_ATRAC3PAL,
638 /* subtitle codecs */
639 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
640 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
641 AV_CODEC_ID_DVB_SUBTITLE,
642 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
645 AV_CODEC_ID_MOV_TEXT,
646 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
647 AV_CODEC_ID_DVB_TELETEXT,
650 AV_CODEC_ID_MICRODVD = 0x17800,
654 AV_CODEC_ID_REALTEXT,
656 AV_CODEC_ID_SUBVIEWER1,
657 AV_CODEC_ID_SUBVIEWER,
664 AV_CODEC_ID_HDMV_TEXT_SUBTITLE,
666 /* other specific kind of codecs (generally used for attachments) */
667 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
668 AV_CODEC_ID_TTF = 0x18000,
670 AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
671 AV_CODEC_ID_BINTEXT = 0x18800,
675 AV_CODEC_ID_SMPTE_KLV,
677 AV_CODEC_ID_TIMED_ID3,
678 AV_CODEC_ID_BIN_DATA,
681 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
683 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
684 * stream (only used by libavformat) */
685 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
686 * stream (only used by libavformat) */
687 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
688 AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
692 * This struct describes the properties of a single codec described by an
694 * @see avcodec_descriptor_get()
696 typedef struct AVCodecDescriptor {
698 enum AVMediaType type;
700 * Name of the codec described by this descriptor. It is non-empty and
701 * unique for each codec descriptor. It should contain alphanumeric
702 * characters and '_' only.
706 * A more descriptive name for this codec. May be NULL.
708 const char *long_name;
710 * Codec properties, a combination of AV_CODEC_PROP_* flags.
714 * MIME type(s) associated with the codec.
715 * May be NULL; if not, a NULL-terminated array of MIME types.
716 * The first item is always non-NULL and is the preferred MIME type.
718 const char *const *mime_types;
720 * If non-NULL, an array of profiles recognized for this codec.
721 * Terminated with FF_PROFILE_UNKNOWN.
723 const struct AVProfile *profiles;
727 * Codec uses only intra compression.
728 * Video and audio codecs only.
730 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
732 * Codec supports lossy compression. Audio and video codecs only.
733 * @note a codec may support both lossy and lossless
736 #define AV_CODEC_PROP_LOSSY (1 << 1)
738 * Codec supports lossless compression. Audio and video codecs only.
740 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
742 * Codec supports frame reordering. That is, the coded order (the order in which
743 * the encoded packets are output by the encoders / stored / input to the
744 * decoders) may be different from the presentation order of the corresponding
747 * For codecs that do not have this property set, PTS and DTS should always be
750 #define AV_CODEC_PROP_REORDER (1 << 3)
752 * Subtitle codec is bitmap based
753 * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
755 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
757 * Subtitle codec is text based.
758 * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
760 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
763 * @ingroup lavc_decoding
764 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
765 * This is mainly needed because some optimized bitstream readers read
766 * 32 or 64 bit at once and could read over the end.<br>
767 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
768 * MPEG bitstreams could cause overread and segfault.
770 #define AV_INPUT_BUFFER_PADDING_SIZE 32
773 * @ingroup lavc_encoding
774 * minimum encoding buffer size
775 * Used to avoid some checks during header writing.
777 #define AV_INPUT_BUFFER_MIN_SIZE 16384
780 * @ingroup lavc_decoding
783 /* We leave some space between them for extensions (drop some
784 * keyframes for intra-only or drop just some bidir frames). */
785 AVDISCARD_NONE =-16, ///< discard nothing
786 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
787 AVDISCARD_NONREF = 8, ///< discard all non reference
788 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
789 AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
790 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
791 AVDISCARD_ALL = 48, ///< discard all
794 enum AVAudioServiceType {
795 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
796 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
797 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
798 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
799 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
800 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
801 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
802 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
803 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
804 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
808 * @ingroup lavc_encoding
810 typedef struct RcOverride{
813 int qscale; // If this is 0 then quality_factor will be used instead.
814 float quality_factor;
818 These flags can be passed in AVCodecContext.flags before initialization.
819 Note: Not everything is supported yet.
823 * Allow decoders to produce frames with data planes that are not aligned
824 * to CPU requirements (e.g. due to cropping).
826 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
830 #define AV_CODEC_FLAG_QSCALE (1 << 1)
832 * 4 MV per MB allowed / advanced prediction for H.263.
834 #define AV_CODEC_FLAG_4MV (1 << 2)
836 * Output even those frames that might be corrupted.
838 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
842 #define AV_CODEC_FLAG_QPEL (1 << 4)
844 * Use internal 2pass ratecontrol in first pass mode.
846 #define AV_CODEC_FLAG_PASS1 (1 << 9)
848 * Use internal 2pass ratecontrol in second pass mode.
850 #define AV_CODEC_FLAG_PASS2 (1 << 10)
854 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
856 * Only decode/encode grayscale.
858 #define AV_CODEC_FLAG_GRAY (1 << 13)
860 * error[?] variables will be set during encoding.
862 #define AV_CODEC_FLAG_PSNR (1 << 15)
864 * Input bitstream might be truncated at a random location
865 * instead of only at frame boundaries.
867 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
869 * Use interlaced DCT.
871 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
875 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
877 * Place global headers in extradata instead of every keyframe.
879 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
881 * Use only bitexact stuff (except (I)DCT).
883 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
884 /* Fx : Flag for H.263+ extra options */
886 * H.263 advanced intra coding / MPEG-4 AC prediction
888 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
890 * interlaced motion estimation
892 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
893 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
896 * Allow non spec compliant speedup tricks.
898 #define AV_CODEC_FLAG2_FAST (1 << 0)
900 * Skip bitstream encoding.
902 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
904 * Place global headers at every keyframe instead of in extradata.
906 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
909 * timecode is in drop frame format. DEPRECATED!!!!
911 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
914 * Input bitstream might be truncated at a packet boundaries
915 * instead of only at frame boundaries.
917 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
919 * Discard cropping information from SPS.
921 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
924 * Show all frames before the first keyframe
926 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
928 * Export motion vectors through frame side data
930 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
932 * Do not skip samples and export skip information as frame side data
934 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
936 * Do not reset ASS ReadOrder field on flush (subtitles decoding)
938 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
940 /* Unsupported options :
941 * Syntax Arithmetic coding (SAC)
942 * Reference Picture Selection
943 * Independent Segment Decoding */
945 /* codec capabilities */
948 * Decoder can use draw_horiz_band callback.
950 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
952 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
953 * If not set, it might not use get_buffer() at all or use operations that
954 * assume the buffer was allocated by avcodec_default_get_buffer.
956 #define AV_CODEC_CAP_DR1 (1 << 1)
957 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
959 * Encoder or decoder requires flushing with NULL input at the end in order to
960 * give the complete and correct output.
962 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
963 * with NULL data. The user can still send NULL data to the public encode
964 * or decode function, but libavcodec will not pass it along to the codec
965 * unless this flag is set.
968 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
969 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
973 * The encoder needs to be fed with NULL data at the end of encoding until the
974 * encoder no longer returns data.
976 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
977 * flag also means that the encoder must set the pts and duration for
978 * each output packet. If this flag is not set, the pts and duration will
979 * be determined by libavcodec from the input frame.
981 #define AV_CODEC_CAP_DELAY (1 << 5)
983 * Codec can be fed a final frame with a smaller size.
984 * This can be used to prevent truncation of the last audio samples.
986 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
989 * Codec can output multiple frames per AVPacket
990 * Normally demuxers return one frame at a time, demuxers which do not do
991 * are connected to a parser to split what they return into proper frames.
992 * This flag is reserved to the very rare category of codecs which have a
993 * bitstream that cannot be split into frames without timeconsuming
994 * operations like full decoding. Demuxers carrying such bitstreams thus
995 * may return multiple frames in a packet. This has many disadvantages like
996 * prohibiting stream copy in many cases thus it should only be considered
999 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1001 * Codec is experimental and is thus avoided in favor of non experimental
1004 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1006 * Codec should fill in channel configuration and samplerate instead of container
1008 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1010 * Codec supports frame-level multithreading.
1012 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1014 * Codec supports slice-based (or partition-based) multithreading.
1016 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1018 * Codec supports changed parameters at any point.
1020 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1022 * Codec supports avctx->thread_count == 0 (auto).
1024 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1026 * Audio encoder supports receiving a different number of samples in each call.
1028 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1030 * Decoder is not a preferred choice for probing.
1031 * This indicates that the decoder is not a good choice for probing.
1032 * It could for example be an expensive to spin up hardware decoder,
1033 * or it could simply not provide a lot of useful information about
1035 * A decoder marked with this flag should only be used as last resort
1036 * choice for probing.
1038 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1040 * Codec is intra only.
1042 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1044 * Codec is lossless.
1046 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1050 * This specifies the area which should be displayed.
1051 * Note there may be multiple such areas for one frame.
1053 typedef struct AVPanScan {
1056 * - encoding: Set by user.
1057 * - decoding: Set by libavcodec.
1062 * width and height in 1/16 pel
1063 * - encoding: Set by user.
1064 * - decoding: Set by libavcodec.
1070 * position of the top left corner in 1/16 pel for up to 3 fields/frames
1071 * - encoding: Set by user.
1072 * - decoding: Set by libavcodec.
1074 int16_t position[3][2];
1078 * This structure describes the bitrate properties of an encoded bitstream. It
1079 * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1080 * parameters for H.264/HEVC.
1082 typedef struct AVCPBProperties {
1084 * Maximum bitrate of the stream, in bits per second.
1085 * Zero if unknown or unspecified.
1089 * Minimum bitrate of the stream, in bits per second.
1090 * Zero if unknown or unspecified.
1094 * Average bitrate of the stream, in bits per second.
1095 * Zero if unknown or unspecified.
1100 * The size of the buffer to which the ratecontrol is applied, in bits.
1101 * Zero if unknown or unspecified.
1106 * The delay between the time the packet this structure is associated with
1107 * is received and the time when it should be decoded, in periods of a 27MHz
1110 * UINT64_MAX when unknown or unspecified.
1116 * The decoder will keep a reference to the frame and may reuse it later.
1118 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1121 * @defgroup lavc_packet AVPacket
1123 * Types and functions for working with AVPacket.
1126 enum AVPacketSideDataType {
1128 * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1129 * bytes worth of palette. This side data signals that a new palette is
1132 AV_PKT_DATA_PALETTE,
1135 * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1136 * that the extradata buffer was changed and the receiving side should
1137 * act upon it appropriately. The new extradata is embedded in the side
1138 * data buffer and should be immediately used for processing the current
1141 AV_PKT_DATA_NEW_EXTRADATA,
1144 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1147 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1148 * s32le channel_count
1149 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1150 * u64le channel_layout
1151 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1153 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1158 AV_PKT_DATA_PARAM_CHANGE,
1161 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1162 * structures with info about macroblocks relevant to splitting the
1163 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1164 * That is, it does not necessarily contain info about all macroblocks,
1165 * as long as the distance between macroblocks in the info is smaller
1166 * than the target payload size.
1167 * Each MB info structure is 12 bytes, and is laid out as follows:
1169 * u32le bit offset from the start of the packet
1170 * u8 current quantizer at the start of the macroblock
1172 * u16le macroblock address within the GOB
1173 * u8 horizontal MV predictor
1174 * u8 vertical MV predictor
1175 * u8 horizontal MV predictor for block number 3
1176 * u8 vertical MV predictor for block number 3
1179 AV_PKT_DATA_H263_MB_INFO,
1182 * This side data should be associated with an audio stream and contains
1183 * ReplayGain information in form of the AVReplayGain struct.
1185 AV_PKT_DATA_REPLAYGAIN,
1188 * This side data contains a 3x3 transformation matrix describing an affine
1189 * transformation that needs to be applied to the decoded video frames for
1190 * correct presentation.
1192 * See libavutil/display.h for a detailed description of the data.
1194 AV_PKT_DATA_DISPLAYMATRIX,
1197 * This side data should be associated with a video stream and contains
1198 * Stereoscopic 3D information in form of the AVStereo3D struct.
1200 AV_PKT_DATA_STEREO3D,
1203 * This side data should be associated with an audio stream and corresponds
1204 * to enum AVAudioServiceType.
1206 AV_PKT_DATA_AUDIO_SERVICE_TYPE,
1209 * This side data contains quality related information from the encoder.
1211 * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1215 * u64le[error count] sum of squared differences between encoder in and output
1218 AV_PKT_DATA_QUALITY_STATS,
1221 * This side data contains an integer value representing the stream index
1222 * of a "fallback" track. A fallback track indicates an alternate
1223 * track to use when the current track can not be decoded for some reason.
1224 * e.g. no decoder available for codec.
1226 AV_PKT_DATA_FALLBACK_TRACK,
1229 * This side data corresponds to the AVCPBProperties struct.
1231 AV_PKT_DATA_CPB_PROPERTIES,
1234 * Recommmends skipping the specified number of samples
1236 * u32le number of samples to skip from start of this packet
1237 * u32le number of samples to skip from end of this packet
1238 * u8 reason for start skip
1239 * u8 reason for end skip (0=padding silence, 1=convergence)
1242 AV_PKT_DATA_SKIP_SAMPLES,
1245 * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1246 * the packet may contain "dual mono" audio specific to Japanese DTV
1247 * and if it is true, recommends only the selected channel to be used.
1249 * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1252 AV_PKT_DATA_JP_DUALMONO,
1255 * A list of zero terminated key/value strings. There is no end marker for
1256 * the list, so it is required to rely on the side data size to stop.
1258 AV_PKT_DATA_STRINGS_METADATA,
1261 * Subtitle event position
1269 AV_PKT_DATA_SUBTITLE_POSITION,
1272 * Data found in BlockAdditional element of matroska container. There is
1273 * no end marker for the data, so it is required to rely on the side data
1274 * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1277 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1280 * The optional first identifier line of a WebVTT cue.
1282 AV_PKT_DATA_WEBVTT_IDENTIFIER,
1285 * The optional settings (rendering instructions) that immediately
1286 * follow the timestamp specifier of a WebVTT cue.
1288 AV_PKT_DATA_WEBVTT_SETTINGS,
1291 * A list of zero terminated key/value strings. There is no end marker for
1292 * the list, so it is required to rely on the side data size to stop. This
1293 * side data includes updated metadata which appeared in the stream.
1295 AV_PKT_DATA_METADATA_UPDATE,
1298 * MPEGTS stream ID, this is required to pass the stream ID
1299 * information from the demuxer to the corresponding muxer.
1301 AV_PKT_DATA_MPEGTS_STREAM_ID,
1304 * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1305 * should be associated with a video stream and contains data in the form
1306 * of the AVMasteringDisplayMetadata struct.
1308 AV_PKT_DATA_MASTERING_DISPLAY_METADATA,
1311 * This side data should be associated with a video stream and corresponds
1312 * to the AVSphericalMapping structure.
1314 AV_PKT_DATA_SPHERICAL,
1317 * Content light level (based on CTA-861.3). This metadata should be
1318 * associated with a video stream and contains data in the form of the
1319 * AVContentLightMetadata struct.
1321 AV_PKT_DATA_CONTENT_LIGHT_LEVEL,
1324 * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1325 * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1326 * The number of bytes of CC data is AVPacketSideData.size.
1331 * The number of side data types.
1332 * This is not part of the public API/ABI in the sense that it may
1333 * change when new side data types are added.
1334 * This must stay the last enum value.
1335 * If its value becomes huge, some code using it
1336 * needs to be updated as it assumes it to be smaller than other limits.
1341 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1343 typedef struct AVPacketSideData {
1346 enum AVPacketSideDataType type;
1350 * This structure stores compressed data. It is typically exported by demuxers
1351 * and then passed as input to decoders, or received as output from encoders and
1352 * then passed to muxers.
1354 * For video, it should typically contain one compressed frame. For audio it may
1355 * contain several compressed frames. Encoders are allowed to output empty
1356 * packets, with no compressed data, containing only side data
1357 * (e.g. to update some stream parameters at the end of encoding).
1359 * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1360 * ABI. Thus it may be allocated on stack and no new fields can be added to it
1361 * without libavcodec and libavformat major bump.
1363 * The semantics of data ownership depends on the buf field.
1364 * If it is set, the packet data is dynamically allocated and is
1365 * valid indefinitely until a call to av_packet_unref() reduces the
1366 * reference count to 0.
1368 * If the buf field is not set av_packet_ref() would make a copy instead
1369 * of increasing the reference count.
1371 * The side data is always allocated with av_malloc(), copied by
1372 * av_packet_ref() and freed by av_packet_unref().
1374 * @see av_packet_ref
1375 * @see av_packet_unref
1377 typedef struct AVPacket {
1379 * A reference to the reference-counted buffer where the packet data is
1381 * May be NULL, then the packet data is not reference-counted.
1385 * Presentation timestamp in AVStream->time_base units; the time at which
1386 * the decompressed packet will be presented to the user.
1387 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1388 * pts MUST be larger or equal to dts as presentation cannot happen before
1389 * decompression, unless one wants to view hex dumps. Some formats misuse
1390 * the terms dts and pts/cts to mean something different. Such timestamps
1391 * must be converted to true pts/dts before they are stored in AVPacket.
1395 * Decompression timestamp in AVStream->time_base units; the time at which
1396 * the packet is decompressed.
1397 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1404 * A combination of AV_PKT_FLAG values
1408 * Additional packet data that can be provided by the container.
1409 * Packet can contain several types of side information.
1411 AVPacketSideData *side_data;
1412 int side_data_elems;
1415 * Duration of this packet in AVStream->time_base units, 0 if unknown.
1416 * Equals next_pts - this_pts in presentation order.
1420 int64_t pos; ///< byte position in stream, -1 if unknown
1422 #if FF_API_CONVERGENCE_DURATION
1424 * @deprecated Same as the duration field, but as int64_t. This was required
1425 * for Matroska subtitles, whose duration values could overflow when the
1426 * duration field was still an int.
1428 attribute_deprecated
1429 int64_t convergence_duration;
1432 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1433 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1435 * Flag is used to discard packets which are required to maintain valid
1436 * decoder state but are not required for output and should be dropped
1439 #define AV_PKT_FLAG_DISCARD 0x0004
1441 * The packet comes from a trusted source.
1443 * Otherwise-unsafe constructs such as arbitrary pointers to data
1444 * outside the packet may be followed.
1446 #define AV_PKT_FLAG_TRUSTED 0x0008
1448 enum AVSideDataParamChangeFlags {
1449 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1450 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1451 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1452 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1458 struct AVCodecInternal;
1462 AV_FIELD_PROGRESSIVE,
1463 AV_FIELD_TT, //< Top coded_first, top displayed first
1464 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1465 AV_FIELD_TB, //< Top coded first, bottom displayed first
1466 AV_FIELD_BT, //< Bottom coded first, top displayed first
1470 * main external API structure.
1471 * New fields can be added to the end with minor version bumps.
1472 * Removal, reordering and changes to existing fields require a major
1474 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1476 * The name string for AVOptions options matches the associated command line
1477 * parameter name and can be found in libavcodec/options_table.h
1478 * The AVOption/command line parameter names differ in some cases from the C
1479 * structure field names for historic reasons or brevity.
1480 * sizeof(AVCodecContext) must not be used outside libav*.
1482 typedef struct AVCodecContext {
1484 * information on struct for av_log
1485 * - set by avcodec_alloc_context3
1487 const AVClass *av_class;
1488 int log_level_offset;
1490 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1491 const struct AVCodec *codec;
1492 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1495 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1496 * This is used to work around some encoder bugs.
1497 * A demuxer should set this to what is stored in the field used to identify the codec.
1498 * If there are multiple such fields in a container then the demuxer should choose the one
1499 * which maximizes the information about the used codec.
1500 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1501 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1502 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1504 * - encoding: Set by user, if not then the default based on codec_id will be used.
1505 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1507 unsigned int codec_tag;
1512 * Private context used for internal data.
1514 * Unlike priv_data, this is not codec-specific. It is used in general
1515 * libavcodec functions.
1517 struct AVCodecInternal *internal;
1520 * Private data of the user, can be used to carry app specific stuff.
1521 * - encoding: Set by user.
1522 * - decoding: Set by user.
1527 * the average bitrate
1528 * - encoding: Set by user; unused for constant quantizer encoding.
1529 * - decoding: Set by user, may be overwritten by libavcodec
1530 * if this info is available in the stream
1535 * number of bits the bitstream is allowed to diverge from the reference.
1536 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1537 * - encoding: Set by user; unused for constant quantizer encoding.
1538 * - decoding: unused
1540 int bit_rate_tolerance;
1543 * Global quality for codecs which cannot change it per frame.
1544 * This should be proportional to MPEG-1/2/4 qscale.
1545 * - encoding: Set by user.
1546 * - decoding: unused
1551 * - encoding: Set by user.
1552 * - decoding: unused
1554 int compression_level;
1555 #define FF_COMPRESSION_DEFAULT -1
1559 * - encoding: Set by user.
1560 * - decoding: Set by user.
1566 * - encoding: Set by user.
1567 * - decoding: Set by user.
1572 * some codecs need / can use extradata like Huffman tables.
1573 * MJPEG: Huffman tables
1574 * rv10: additional flags
1575 * MPEG-4: global headers (they can be in the bitstream or here)
1576 * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1577 * than extradata_size to avoid problems if it is read with the bitstream reader.
1578 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1579 * - encoding: Set/allocated/freed by libavcodec.
1580 * - decoding: Set/allocated/freed by user.
1586 * This is the fundamental unit of time (in seconds) in terms
1587 * of which frame timestamps are represented. For fixed-fps content,
1588 * timebase should be 1/framerate and timestamp increments should be
1590 * This often, but not always is the inverse of the frame rate or field rate
1591 * for video. 1/time_base is not the average frame rate if the frame rate is not
1594 * Like containers, elementary streams also can store timestamps, 1/time_base
1595 * is the unit in which these timestamps are specified.
1596 * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1597 * vop_time_increment_resolution and fixed_vop_rate
1598 * (fixed_vop_rate == 0 implies that it is different from the framerate)
1600 * - encoding: MUST be set by user.
1601 * - decoding: the use of this field for decoding is deprecated.
1602 * Use framerate instead.
1604 AVRational time_base;
1607 * For some codecs, the time base is closer to the field rate than the frame rate.
1608 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1609 * if no telecine is used ...
1611 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1613 int ticks_per_frame;
1618 * Encoding: Number of frames delay there will be from the encoder input to
1619 * the decoder output. (we assume the decoder matches the spec)
1620 * Decoding: Number of frames delay in addition to what a standard decoder
1621 * as specified in the spec would produce.
1624 * Number of frames the decoded output will be delayed relative to the
1628 * For encoding, this field is unused (see initial_padding).
1630 * For decoding, this is the number of samples the decoder needs to
1631 * output before the decoder's output is valid. When seeking, you should
1632 * start decoding this many samples prior to your desired seek point.
1634 * - encoding: Set by libavcodec.
1635 * - decoding: Set by libavcodec.
1642 * picture width / height.
1644 * @note Those fields may not match the values of the last
1645 * AVFrame output by avcodec_decode_video2 due frame
1648 * - encoding: MUST be set by user.
1649 * - decoding: May be set by the user before opening the decoder if known e.g.
1650 * from the container. Some decoders will require the dimensions
1651 * to be set by the caller. During decoding, the decoder may
1652 * overwrite those values as required while parsing the data.
1657 * Bitstream width / height, may be different from width/height e.g. when
1658 * the decoded frame is cropped before being output or lowres is enabled.
1660 * @note Those field may not match the value of the last
1661 * AVFrame output by avcodec_receive_frame() due frame
1664 * - encoding: unused
1665 * - decoding: May be set by the user before opening the decoder if known
1666 * e.g. from the container. During decoding, the decoder may
1667 * overwrite those values as required while parsing the data.
1669 int coded_width, coded_height;
1672 * the number of pictures in a group of pictures, or 0 for intra_only
1673 * - encoding: Set by user.
1674 * - decoding: unused
1679 * Pixel format, see AV_PIX_FMT_xxx.
1680 * May be set by the demuxer if known from headers.
1681 * May be overridden by the decoder if it knows better.
1683 * @note This field may not match the value of the last
1684 * AVFrame output by avcodec_receive_frame() due frame
1687 * - encoding: Set by user.
1688 * - decoding: Set by user if known, overridden by libavcodec while
1691 enum AVPixelFormat pix_fmt;
1694 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1695 * decoder to draw a horizontal band. It improves cache usage. Not
1696 * all codecs can do that. You must check the codec capabilities
1698 * When multithreading is used, it may be called from multiple threads
1699 * at the same time; threads might draw different parts of the same AVFrame,
1700 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1702 * The function is also used by hardware acceleration APIs.
1703 * It is called at least once during frame decoding to pass
1704 * the data needed for hardware render.
1705 * In that mode instead of pixel data, AVFrame points to
1706 * a structure specific to the acceleration API. The application
1707 * reads the structure and can change some fields to indicate progress
1709 * - encoding: unused
1710 * - decoding: Set by user.
1711 * @param height the height of the slice
1712 * @param y the y position of the slice
1713 * @param type 1->top field, 2->bottom field, 3->frame
1714 * @param offset offset into the AVFrame.data from which the slice should be read
1716 void (*draw_horiz_band)(struct AVCodecContext *s,
1717 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1718 int y, int type, int height);
1721 * callback to negotiate the pixelFormat
1722 * @param fmt is the list of formats which are supported by the codec,
1723 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1724 * The first is always the native one.
1725 * @note The callback may be called again immediately if initialization for
1726 * the selected (hardware-accelerated) pixel format failed.
1727 * @warning Behavior is undefined if the callback returns a value not
1728 * in the fmt list of formats.
1729 * @return the chosen format
1730 * - encoding: unused
1731 * - decoding: Set by user, if not set the native format will be chosen.
1733 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1736 * maximum number of B-frames between non-B-frames
1737 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1738 * - encoding: Set by user.
1739 * - decoding: unused
1744 * qscale factor between IP and B-frames
1745 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1746 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1747 * - encoding: Set by user.
1748 * - decoding: unused
1750 float b_quant_factor;
1752 #if FF_API_PRIVATE_OPT
1753 /** @deprecated use encoder private options instead */
1754 attribute_deprecated
1755 int b_frame_strategy;
1759 * qscale offset between IP and B-frames
1760 * - encoding: Set by user.
1761 * - decoding: unused
1763 float b_quant_offset;
1766 * Size of the frame reordering buffer in the decoder.
1767 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1768 * - encoding: Set by libavcodec.
1769 * - decoding: Set by libavcodec.
1773 #if FF_API_PRIVATE_OPT
1774 /** @deprecated use encoder private options instead */
1775 attribute_deprecated
1780 * qscale factor between P- and I-frames
1781 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1782 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1783 * - encoding: Set by user.
1784 * - decoding: unused
1786 float i_quant_factor;
1789 * qscale offset between P and I-frames
1790 * - encoding: Set by user.
1791 * - decoding: unused
1793 float i_quant_offset;
1796 * luminance masking (0-> disabled)
1797 * - encoding: Set by user.
1798 * - decoding: unused
1803 * temporary complexity masking (0-> disabled)
1804 * - encoding: Set by user.
1805 * - decoding: unused
1807 float temporal_cplx_masking;
1810 * spatial complexity masking (0-> disabled)
1811 * - encoding: Set by user.
1812 * - decoding: unused
1814 float spatial_cplx_masking;
1817 * p block masking (0-> disabled)
1818 * - encoding: Set by user.
1819 * - decoding: unused
1824 * darkness masking (0-> disabled)
1825 * - encoding: Set by user.
1826 * - decoding: unused
1832 * - encoding: Set by libavcodec.
1833 * - decoding: Set by user (or 0).
1837 #if FF_API_PRIVATE_OPT
1838 /** @deprecated use encoder private options instead */
1839 attribute_deprecated
1840 int prediction_method;
1841 #define FF_PRED_LEFT 0
1842 #define FF_PRED_PLANE 1
1843 #define FF_PRED_MEDIAN 2
1847 * slice offsets in the frame in bytes
1848 * - encoding: Set/allocated by libavcodec.
1849 * - decoding: Set/allocated by user (or NULL).
1854 * sample aspect ratio (0 if unknown)
1855 * That is the width of a pixel divided by the height of the pixel.
1856 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1857 * - encoding: Set by user.
1858 * - decoding: Set by libavcodec.
1860 AVRational sample_aspect_ratio;
1863 * motion estimation comparison function
1864 * - encoding: Set by user.
1865 * - decoding: unused
1869 * subpixel motion estimation comparison function
1870 * - encoding: Set by user.
1871 * - decoding: unused
1875 * macroblock comparison function (not supported yet)
1876 * - encoding: Set by user.
1877 * - decoding: unused
1881 * interlaced DCT comparison function
1882 * - encoding: Set by user.
1883 * - decoding: unused
1886 #define FF_CMP_SAD 0
1887 #define FF_CMP_SSE 1
1888 #define FF_CMP_SATD 2
1889 #define FF_CMP_DCT 3
1890 #define FF_CMP_PSNR 4
1891 #define FF_CMP_BIT 5
1893 #define FF_CMP_ZERO 7
1894 #define FF_CMP_VSAD 8
1895 #define FF_CMP_VSSE 9
1896 #define FF_CMP_NSSE 10
1897 #define FF_CMP_W53 11
1898 #define FF_CMP_W97 12
1899 #define FF_CMP_DCTMAX 13
1900 #define FF_CMP_DCT264 14
1901 #define FF_CMP_MEDIAN_SAD 15
1902 #define FF_CMP_CHROMA 256
1905 * ME diamond size & shape
1906 * - encoding: Set by user.
1907 * - decoding: unused
1912 * amount of previous MV predictors (2a+1 x 2a+1 square)
1913 * - encoding: Set by user.
1914 * - decoding: unused
1916 int last_predictor_count;
1918 #if FF_API_PRIVATE_OPT
1919 /** @deprecated use encoder private options instead */
1920 attribute_deprecated
1925 * motion estimation prepass comparison function
1926 * - encoding: Set by user.
1927 * - decoding: unused
1932 * ME prepass diamond size & shape
1933 * - encoding: Set by user.
1934 * - decoding: unused
1940 * - encoding: Set by user.
1941 * - decoding: unused
1943 int me_subpel_quality;
1946 * maximum motion estimation search range in subpel units
1947 * If 0 then no limit.
1949 * - encoding: Set by user.
1950 * - decoding: unused
1956 * - encoding: unused
1957 * - decoding: Set by user.
1960 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1961 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1962 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1965 * macroblock decision mode
1966 * - encoding: Set by user.
1967 * - decoding: unused
1970 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1971 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1972 #define FF_MB_DECISION_RD 2 ///< rate distortion
1975 * custom intra quantization matrix
1976 * - encoding: Set by user, can be NULL.
1977 * - decoding: Set by libavcodec.
1979 uint16_t *intra_matrix;
1982 * custom inter quantization matrix
1983 * - encoding: Set by user, can be NULL.
1984 * - decoding: Set by libavcodec.
1986 uint16_t *inter_matrix;
1988 #if FF_API_PRIVATE_OPT
1989 /** @deprecated use encoder private options instead */
1990 attribute_deprecated
1991 int scenechange_threshold;
1993 /** @deprecated use encoder private options instead */
1994 attribute_deprecated
1995 int noise_reduction;
1999 * precision of the intra DC coefficient - 8
2000 * - encoding: Set by user.
2001 * - decoding: Set by libavcodec
2003 int intra_dc_precision;
2006 * Number of macroblock rows at the top which are skipped.
2007 * - encoding: unused
2008 * - decoding: Set by user.
2013 * Number of macroblock rows at the bottom which are skipped.
2014 * - encoding: unused
2015 * - decoding: Set by user.
2020 * minimum MB Lagrange multiplier
2021 * - encoding: Set by user.
2022 * - decoding: unused
2027 * maximum MB Lagrange multiplier
2028 * - encoding: Set by user.
2029 * - decoding: unused
2033 #if FF_API_PRIVATE_OPT
2035 * @deprecated use encoder private options instead
2037 attribute_deprecated
2038 int me_penalty_compensation;
2042 * - encoding: Set by user.
2043 * - decoding: unused
2047 #if FF_API_PRIVATE_OPT
2048 /** @deprecated use encoder private options instead */
2049 attribute_deprecated
2055 * - encoding: Set by user.
2056 * - decoding: unused
2061 * number of reference frames
2062 * - encoding: Set by user.
2063 * - decoding: Set by lavc.
2067 #if FF_API_PRIVATE_OPT
2068 /** @deprecated use encoder private options instead */
2069 attribute_deprecated
2074 * Note: Value depends upon the compare function used for fullpel ME.
2075 * - encoding: Set by user.
2076 * - decoding: unused
2080 #if FF_API_PRIVATE_OPT
2081 /** @deprecated use encoder private options instead */
2082 attribute_deprecated
2087 * Chromaticity coordinates of the source primaries.
2088 * - encoding: Set by user
2089 * - decoding: Set by libavcodec
2091 enum AVColorPrimaries color_primaries;
2094 * Color Transfer Characteristic.
2095 * - encoding: Set by user
2096 * - decoding: Set by libavcodec
2098 enum AVColorTransferCharacteristic color_trc;
2101 * YUV colorspace type.
2102 * - encoding: Set by user
2103 * - decoding: Set by libavcodec
2105 enum AVColorSpace colorspace;
2108 * MPEG vs JPEG YUV range.
2109 * - encoding: Set by user
2110 * - decoding: Set by libavcodec
2112 enum AVColorRange color_range;
2115 * This defines the location of chroma samples.
2116 * - encoding: Set by user
2117 * - decoding: Set by libavcodec
2119 enum AVChromaLocation chroma_sample_location;
2123 * Indicates number of picture subdivisions. Used for parallelized
2125 * - encoding: Set by user
2126 * - decoding: unused
2131 * - encoding: set by libavcodec
2132 * - decoding: Set by user.
2134 enum AVFieldOrder field_order;
2137 int sample_rate; ///< samples per second
2138 int channels; ///< number of audio channels
2141 * audio sample format
2142 * - encoding: Set by user.
2143 * - decoding: Set by libavcodec.
2145 enum AVSampleFormat sample_fmt; ///< sample format
2147 /* The following data should not be initialized. */
2149 * Number of samples per channel in an audio frame.
2151 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2152 * except the last must contain exactly frame_size samples per channel.
2153 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2154 * frame size is not restricted.
2155 * - decoding: may be set by some decoders to indicate constant frame size
2160 * Frame counter, set by libavcodec.
2162 * - decoding: total number of frames returned from the decoder so far.
2163 * - encoding: total number of frames passed to the encoder so far.
2165 * @note the counter is not incremented if encoding/decoding resulted in
2171 * number of bytes per packet if constant and known or 0
2172 * Used by some WAV based audio codecs.
2177 * Audio cutoff bandwidth (0 means "automatic")
2178 * - encoding: Set by user.
2179 * - decoding: unused
2184 * Audio channel layout.
2185 * - encoding: set by user.
2186 * - decoding: set by user, may be overwritten by libavcodec.
2188 uint64_t channel_layout;
2191 * Request decoder to use this channel layout if it can (0 for default)
2192 * - encoding: unused
2193 * - decoding: Set by user.
2195 uint64_t request_channel_layout;
2198 * Type of service that the audio stream conveys.
2199 * - encoding: Set by user.
2200 * - decoding: Set by libavcodec.
2202 enum AVAudioServiceType audio_service_type;
2205 * desired sample format
2206 * - encoding: Not used.
2207 * - decoding: Set by user.
2208 * Decoder will decode to this format if it can.
2210 enum AVSampleFormat request_sample_fmt;
2213 * This callback is called at the beginning of each frame to get data
2214 * buffer(s) for it. There may be one contiguous buffer for all the data or
2215 * there may be a buffer per each data plane or anything in between. What
2216 * this means is, you may set however many entries in buf[] you feel necessary.
2217 * Each buffer must be reference-counted using the AVBuffer API (see description
2220 * The following fields will be set in the frame before this callback is
2223 * - width, height (video only)
2224 * - sample_rate, channel_layout, nb_samples (audio only)
2225 * Their values may differ from the corresponding values in
2226 * AVCodecContext. This callback must use the frame values, not the codec
2227 * context values, to calculate the required buffer size.
2229 * This callback must fill the following fields in the frame:
2233 * * if the data is planar audio with more than 8 channels, then this
2234 * callback must allocate and fill extended_data to contain all pointers
2235 * to all data planes. data[] must hold as many pointers as it can.
2236 * extended_data must be allocated with av_malloc() and will be freed in
2238 * * otherwise extended_data must point to data
2239 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2240 * the frame's data and extended_data pointers must be contained in these. That
2241 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2242 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2243 * and av_buffer_ref().
2244 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2245 * this callback and filled with the extra buffers if there are more
2246 * buffers than buf[] can hold. extended_buf will be freed in
2249 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2250 * avcodec_default_get_buffer2() instead of providing buffers allocated by
2253 * Each data plane must be aligned to the maximum required by the target
2256 * @see avcodec_default_get_buffer2()
2260 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2261 * (read and/or written to if it is writable) later by libavcodec.
2263 * avcodec_align_dimensions2() should be used to find the required width and
2264 * height, as they normally need to be rounded up to the next multiple of 16.
2266 * Some decoders do not support linesizes changing between frames.
2268 * If frame multithreading is used and thread_safe_callbacks is set,
2269 * this callback may be called from a different thread, but not from more
2270 * than one at once. Does not need to be reentrant.
2272 * @see avcodec_align_dimensions2()
2276 * Decoders request a buffer of a particular size by setting
2277 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2278 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2279 * to a smaller value in the output frame.
2281 * As a convenience, av_samples_get_buffer_size() and
2282 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2283 * functions to find the required data size and to fill data pointers and
2284 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2285 * since all planes must be the same size.
2287 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2289 * - encoding: unused
2290 * - decoding: Set by libavcodec, user can override.
2292 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2295 * If non-zero, the decoded audio and video frames returned from
2296 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2297 * and are valid indefinitely. The caller must free them with
2298 * av_frame_unref() when they are not needed anymore.
2299 * Otherwise, the decoded frames must not be freed by the caller and are
2300 * only valid until the next decode call.
2302 * This is always automatically enabled if avcodec_receive_frame() is used.
2304 * - encoding: unused
2305 * - decoding: set by the caller before avcodec_open2().
2307 attribute_deprecated
2308 int refcounted_frames;
2310 /* - encoding parameters */
2311 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2312 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2316 * - encoding: Set by user.
2317 * - decoding: unused
2323 * - encoding: Set by user.
2324 * - decoding: unused
2329 * maximum quantizer difference between frames
2330 * - encoding: Set by user.
2331 * - decoding: unused
2336 * decoder bitstream buffer size
2337 * - encoding: Set by user.
2338 * - decoding: unused
2343 * ratecontrol override, see RcOverride
2344 * - encoding: Allocated/set/freed by user.
2345 * - decoding: unused
2347 int rc_override_count;
2348 RcOverride *rc_override;
2352 * - encoding: Set by user.
2353 * - decoding: Set by user, may be overwritten by libavcodec.
2355 int64_t rc_max_rate;
2359 * - encoding: Set by user.
2360 * - decoding: unused
2362 int64_t rc_min_rate;
2365 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2366 * - encoding: Set by user.
2367 * - decoding: unused.
2369 float rc_max_available_vbv_use;
2372 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2373 * - encoding: Set by user.
2374 * - decoding: unused.
2376 float rc_min_vbv_overflow_use;
2379 * Number of bits which should be loaded into the rc buffer before decoding starts.
2380 * - encoding: Set by user.
2381 * - decoding: unused
2383 int rc_initial_buffer_occupancy;
2385 #if FF_API_CODER_TYPE
2386 #define FF_CODER_TYPE_VLC 0
2387 #define FF_CODER_TYPE_AC 1
2388 #define FF_CODER_TYPE_RAW 2
2389 #define FF_CODER_TYPE_RLE 3
2391 * @deprecated use encoder private options instead
2393 attribute_deprecated
2395 #endif /* FF_API_CODER_TYPE */
2397 #if FF_API_PRIVATE_OPT
2398 /** @deprecated use encoder private options instead */
2399 attribute_deprecated
2403 #if FF_API_PRIVATE_OPT
2404 /** @deprecated use encoder private options instead */
2405 attribute_deprecated
2406 int frame_skip_threshold;
2408 /** @deprecated use encoder private options instead */
2409 attribute_deprecated
2410 int frame_skip_factor;
2412 /** @deprecated use encoder private options instead */
2413 attribute_deprecated
2416 /** @deprecated use encoder private options instead */
2417 attribute_deprecated
2419 #endif /* FF_API_PRIVATE_OPT */
2422 * trellis RD quantization
2423 * - encoding: Set by user.
2424 * - decoding: unused
2428 #if FF_API_PRIVATE_OPT
2429 /** @deprecated use encoder private options instead */
2430 attribute_deprecated
2431 int min_prediction_order;
2433 /** @deprecated use encoder private options instead */
2434 attribute_deprecated
2435 int max_prediction_order;
2437 /** @deprecated use encoder private options instead */
2438 attribute_deprecated
2439 int64_t timecode_frame_start;
2442 #if FF_API_RTP_CALLBACK
2444 * @deprecated unused
2446 /* The RTP callback: This function is called */
2447 /* every time the encoder has a packet to send. */
2448 /* It depends on the encoder if the data starts */
2449 /* with a Start Code (it should). H.263 does. */
2450 /* mb_nb contains the number of macroblocks */
2451 /* encoded in the RTP payload. */
2452 attribute_deprecated
2453 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2456 #if FF_API_PRIVATE_OPT
2457 /** @deprecated use encoder private options instead */
2458 attribute_deprecated
2459 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2460 /* do its best to deliver a chunk with size */
2461 /* below rtp_payload_size, the chunk will start */
2462 /* with a start code on some codecs like H.263. */
2463 /* This doesn't take account of any particular */
2464 /* headers inside the transmitted RTP payload. */
2467 #if FF_API_STAT_BITS
2468 /* statistics, used for 2-pass encoding */
2469 attribute_deprecated
2471 attribute_deprecated
2473 attribute_deprecated
2475 attribute_deprecated
2477 attribute_deprecated
2479 attribute_deprecated
2481 attribute_deprecated
2483 attribute_deprecated
2486 /** @deprecated this field is unused */
2487 attribute_deprecated
2492 * pass1 encoding statistics output buffer
2493 * - encoding: Set by libavcodec.
2494 * - decoding: unused
2499 * pass2 encoding statistics input buffer
2500 * Concatenated stuff from stats_out of pass1 should be placed here.
2501 * - encoding: Allocated/set/freed by user.
2502 * - decoding: unused
2507 * Work around bugs in encoders which sometimes cannot be detected automatically.
2508 * - encoding: Set by user
2509 * - decoding: Set by user
2511 int workaround_bugs;
2512 #define FF_BUG_AUTODETECT 1 ///< autodetection
2513 #define FF_BUG_XVID_ILACE 4
2514 #define FF_BUG_UMP4 8
2515 #define FF_BUG_NO_PADDING 16
2516 #define FF_BUG_AMV 32
2517 #define FF_BUG_QPEL_CHROMA 64
2518 #define FF_BUG_STD_QPEL 128
2519 #define FF_BUG_QPEL_CHROMA2 256
2520 #define FF_BUG_DIRECT_BLOCKSIZE 512
2521 #define FF_BUG_EDGE 1024
2522 #define FF_BUG_HPEL_CHROMA 2048
2523 #define FF_BUG_DC_CLIP 4096
2524 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2525 #define FF_BUG_TRUNCATED 16384
2526 #define FF_BUG_IEDGE 32768
2529 * strictly follow the standard (MPEG-4, ...).
2530 * - encoding: Set by user.
2531 * - decoding: Set by user.
2532 * Setting this to STRICT or higher means the encoder and decoder will
2533 * generally do stupid things, whereas setting it to unofficial or lower
2534 * will mean the encoder might produce output that is not supported by all
2535 * spec-compliant decoders. Decoders don't differentiate between normal,
2536 * unofficial and experimental (that is, they always try to decode things
2537 * when they can) unless they are explicitly asked to behave stupidly
2538 * (=strictly conform to the specs)
2540 int strict_std_compliance;
2541 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2542 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2543 #define FF_COMPLIANCE_NORMAL 0
2544 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2545 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2548 * error concealment flags
2549 * - encoding: unused
2550 * - decoding: Set by user.
2552 int error_concealment;
2553 #define FF_EC_GUESS_MVS 1
2554 #define FF_EC_DEBLOCK 2
2555 #define FF_EC_FAVOR_INTER 256
2559 * - encoding: Set by user.
2560 * - decoding: Set by user.
2563 #define FF_DEBUG_PICT_INFO 1
2564 #define FF_DEBUG_RC 2
2565 #define FF_DEBUG_BITSTREAM 4
2566 #define FF_DEBUG_MB_TYPE 8
2567 #define FF_DEBUG_QP 16
2570 * @deprecated this option does nothing
2572 #define FF_DEBUG_MV 32
2574 #define FF_DEBUG_DCT_COEFF 0x00000040
2575 #define FF_DEBUG_SKIP 0x00000080
2576 #define FF_DEBUG_STARTCODE 0x00000100
2577 #define FF_DEBUG_ER 0x00000400
2578 #define FF_DEBUG_MMCO 0x00000800
2579 #define FF_DEBUG_BUGS 0x00001000
2581 #define FF_DEBUG_VIS_QP 0x00002000
2582 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2584 #define FF_DEBUG_BUFFERS 0x00008000
2585 #define FF_DEBUG_THREADS 0x00010000
2586 #define FF_DEBUG_GREEN_MD 0x00800000
2587 #define FF_DEBUG_NOMC 0x01000000
2592 * - encoding: Set by user.
2593 * - decoding: Set by user.
2596 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2597 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2598 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2602 * Error recognition; may misdetect some more or less valid parts as errors.
2603 * - encoding: unused
2604 * - decoding: Set by user.
2606 int err_recognition;
2609 * Verify checksums embedded in the bitstream (could be of either encoded or
2610 * decoded data, depending on the codec) and print an error message on mismatch.
2611 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2612 * decoder returning an error.
2614 #define AV_EF_CRCCHECK (1<<0)
2615 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2616 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2617 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2619 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2620 #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
2621 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2622 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2626 * opaque 64-bit number (generally a PTS) that will be reordered and
2627 * output in AVFrame.reordered_opaque
2628 * - encoding: unused
2629 * - decoding: Set by user.
2631 int64_t reordered_opaque;
2634 * Hardware accelerator in use
2635 * - encoding: unused.
2636 * - decoding: Set by libavcodec
2638 const struct AVHWAccel *hwaccel;
2641 * Hardware accelerator context.
2642 * For some hardware accelerators, a global context needs to be
2643 * provided by the user. In that case, this holds display-dependent
2644 * data FFmpeg cannot instantiate itself. Please refer to the
2645 * FFmpeg HW accelerator documentation to know how to fill this
2646 * is. e.g. for VA API, this is a struct vaapi_context.
2647 * - encoding: unused
2648 * - decoding: Set by user
2650 void *hwaccel_context;
2654 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2655 * - decoding: unused
2657 uint64_t error[AV_NUM_DATA_POINTERS];
2660 * DCT algorithm, see FF_DCT_* below
2661 * - encoding: Set by user.
2662 * - decoding: unused
2665 #define FF_DCT_AUTO 0
2666 #define FF_DCT_FASTINT 1
2667 #define FF_DCT_INT 2
2668 #define FF_DCT_MMX 3
2669 #define FF_DCT_ALTIVEC 5
2670 #define FF_DCT_FAAN 6
2673 * IDCT algorithm, see FF_IDCT_* below.
2674 * - encoding: Set by user.
2675 * - decoding: Set by user.
2678 #define FF_IDCT_AUTO 0
2679 #define FF_IDCT_INT 1
2680 #define FF_IDCT_SIMPLE 2
2681 #define FF_IDCT_SIMPLEMMX 3
2682 #define FF_IDCT_ARM 7
2683 #define FF_IDCT_ALTIVEC 8
2684 #define FF_IDCT_SIMPLEARM 10
2685 #define FF_IDCT_XVID 14
2686 #define FF_IDCT_SIMPLEARMV5TE 16
2687 #define FF_IDCT_SIMPLEARMV6 17
2688 #define FF_IDCT_FAAN 20
2689 #define FF_IDCT_SIMPLENEON 22
2690 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2691 #define FF_IDCT_SIMPLEAUTO 128
2694 * bits per sample/pixel from the demuxer (needed for huffyuv).
2695 * - encoding: Set by libavcodec.
2696 * - decoding: Set by user.
2698 int bits_per_coded_sample;
2701 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2702 * - encoding: set by user.
2703 * - decoding: set by libavcodec.
2705 int bits_per_raw_sample;
2709 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2710 * - encoding: unused
2711 * - decoding: Set by user.
2716 #if FF_API_CODED_FRAME
2718 * the picture in the bitstream
2719 * - encoding: Set by libavcodec.
2720 * - decoding: unused
2722 * @deprecated use the quality factor packet side data instead
2724 attribute_deprecated AVFrame *coded_frame;
2729 * is used to decide how many independent tasks should be passed to execute()
2730 * - encoding: Set by user.
2731 * - decoding: Set by user.
2736 * Which multithreading methods to use.
2737 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2738 * so clients which cannot provide future frames should not use it.
2740 * - encoding: Set by user, otherwise the default is used.
2741 * - decoding: Set by user, otherwise the default is used.
2744 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2745 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2748 * Which multithreading methods are in use by the codec.
2749 * - encoding: Set by libavcodec.
2750 * - decoding: Set by libavcodec.
2752 int active_thread_type;
2755 * Set by the client if its custom get_buffer() callback can be called
2756 * synchronously from another thread, which allows faster multithreaded decoding.
2757 * draw_horiz_band() will be called from other threads regardless of this setting.
2758 * Ignored if the default get_buffer() is used.
2759 * - encoding: Set by user.
2760 * - decoding: Set by user.
2762 int thread_safe_callbacks;
2765 * The codec may call this to execute several independent things.
2766 * It will return only after finishing all tasks.
2767 * The user may replace this with some multithreaded implementation,
2768 * the default implementation will execute the parts serially.
2769 * @param count the number of things to execute
2770 * - encoding: Set by libavcodec, user can override.
2771 * - decoding: Set by libavcodec, user can override.
2773 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2776 * The codec may call this to execute several independent things.
2777 * It will return only after finishing all tasks.
2778 * The user may replace this with some multithreaded implementation,
2779 * the default implementation will execute the parts serially.
2780 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2781 * @param c context passed also to func
2782 * @param count the number of things to execute
2783 * @param arg2 argument passed unchanged to func
2784 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2785 * @param func function that will be called count times, with jobnr from 0 to count-1.
2786 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2787 * two instances of func executing at the same time will have the same threadnr.
2788 * @return always 0 currently, but code should handle a future improvement where when any call to func
2789 * returns < 0 no further calls to func may be done and < 0 is returned.
2790 * - encoding: Set by libavcodec, user can override.
2791 * - decoding: Set by libavcodec, user can override.
2793 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2796 * noise vs. sse weight for the nsse comparison function
2797 * - encoding: Set by user.
2798 * - decoding: unused
2804 * - encoding: Set by user.
2805 * - decoding: Set by libavcodec.
2808 #define FF_PROFILE_UNKNOWN -99
2809 #define FF_PROFILE_RESERVED -100
2811 #define FF_PROFILE_AAC_MAIN 0
2812 #define FF_PROFILE_AAC_LOW 1
2813 #define FF_PROFILE_AAC_SSR 2
2814 #define FF_PROFILE_AAC_LTP 3
2815 #define FF_PROFILE_AAC_HE 4
2816 #define FF_PROFILE_AAC_HE_V2 28
2817 #define FF_PROFILE_AAC_LD 22
2818 #define FF_PROFILE_AAC_ELD 38
2819 #define FF_PROFILE_MPEG2_AAC_LOW 128
2820 #define FF_PROFILE_MPEG2_AAC_HE 131
2822 #define FF_PROFILE_DNXHD 0
2823 #define FF_PROFILE_DNXHR_LB 1
2824 #define FF_PROFILE_DNXHR_SQ 2
2825 #define FF_PROFILE_DNXHR_HQ 3
2826 #define FF_PROFILE_DNXHR_HQX 4
2827 #define FF_PROFILE_DNXHR_444 5
2829 #define FF_PROFILE_DTS 20
2830 #define FF_PROFILE_DTS_ES 30
2831 #define FF_PROFILE_DTS_96_24 40
2832 #define FF_PROFILE_DTS_HD_HRA 50
2833 #define FF_PROFILE_DTS_HD_MA 60
2834 #define FF_PROFILE_DTS_EXPRESS 70
2836 #define FF_PROFILE_MPEG2_422 0
2837 #define FF_PROFILE_MPEG2_HIGH 1
2838 #define FF_PROFILE_MPEG2_SS 2
2839 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2840 #define FF_PROFILE_MPEG2_MAIN 4
2841 #define FF_PROFILE_MPEG2_SIMPLE 5
2843 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2844 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2846 #define FF_PROFILE_H264_BASELINE 66
2847 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2848 #define FF_PROFILE_H264_MAIN 77
2849 #define FF_PROFILE_H264_EXTENDED 88
2850 #define FF_PROFILE_H264_HIGH 100
2851 #define FF_PROFILE_H264_HIGH_10 110
2852 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2853 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2854 #define FF_PROFILE_H264_HIGH_422 122
2855 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2856 #define FF_PROFILE_H264_STEREO_HIGH 128
2857 #define FF_PROFILE_H264_HIGH_444 144
2858 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2859 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2860 #define FF_PROFILE_H264_CAVLC_444 44
2862 #define FF_PROFILE_VC1_SIMPLE 0
2863 #define FF_PROFILE_VC1_MAIN 1
2864 #define FF_PROFILE_VC1_COMPLEX 2
2865 #define FF_PROFILE_VC1_ADVANCED 3
2867 #define FF_PROFILE_MPEG4_SIMPLE 0
2868 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2869 #define FF_PROFILE_MPEG4_CORE 2
2870 #define FF_PROFILE_MPEG4_MAIN 3
2871 #define FF_PROFILE_MPEG4_N_BIT 4
2872 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2873 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2874 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2875 #define FF_PROFILE_MPEG4_HYBRID 8
2876 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2877 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2878 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2879 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2880 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2881 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2882 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2884 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2885 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2886 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2887 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2888 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2890 #define FF_PROFILE_VP9_0 0
2891 #define FF_PROFILE_VP9_1 1
2892 #define FF_PROFILE_VP9_2 2
2893 #define FF_PROFILE_VP9_3 3
2895 #define FF_PROFILE_HEVC_MAIN 1
2896 #define FF_PROFILE_HEVC_MAIN_10 2
2897 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2898 #define FF_PROFILE_HEVC_REXT 4
2902 * - encoding: Set by user.
2903 * - decoding: Set by libavcodec.
2906 #define FF_LEVEL_UNKNOWN -99
2909 * Skip loop filtering for selected frames.
2910 * - encoding: unused
2911 * - decoding: Set by user.
2913 enum AVDiscard skip_loop_filter;
2916 * Skip IDCT/dequantization for selected frames.
2917 * - encoding: unused
2918 * - decoding: Set by user.
2920 enum AVDiscard skip_idct;
2923 * Skip decoding for selected frames.
2924 * - encoding: unused
2925 * - decoding: Set by user.
2927 enum AVDiscard skip_frame;
2930 * Header containing style information for text subtitles.
2931 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2932 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2933 * the Format line following. It shouldn't include any Dialogue line.
2934 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2935 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2937 uint8_t *subtitle_header;
2938 int subtitle_header_size;
2940 #if FF_API_VBV_DELAY
2942 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2943 * Used for compliant TS muxing.
2944 * - encoding: Set by libavcodec.
2945 * - decoding: unused.
2946 * @deprecated this value is now exported as a part of
2947 * AV_PKT_DATA_CPB_PROPERTIES packet side data
2949 attribute_deprecated
2953 #if FF_API_SIDEDATA_ONLY_PKT
2955 * Encoding only and set by default. Allow encoders to output packets
2956 * that do not contain any encoded data, only side data.
2958 * Some encoders need to output such packets, e.g. to update some stream
2959 * parameters at the end of encoding.
2961 * @deprecated this field disables the default behaviour and
2962 * it is kept only for compatibility.
2964 attribute_deprecated
2965 int side_data_only_packets;
2969 * Audio only. The number of "priming" samples (padding) inserted by the
2970 * encoder at the beginning of the audio. I.e. this number of leading
2971 * decoded samples must be discarded by the caller to get the original audio
2972 * without leading padding.
2974 * - decoding: unused
2975 * - encoding: Set by libavcodec. The timestamps on the output packets are
2976 * adjusted by the encoder so that they always refer to the
2977 * first sample of the data actually contained in the packet,
2978 * including any added padding. E.g. if the timebase is
2979 * 1/samplerate and the timestamp of the first input sample is
2980 * 0, the timestamp of the first output packet will be
2983 int initial_padding;
2986 * - decoding: For codecs that store a framerate value in the compressed
2987 * bitstream, the decoder may export it here. { 0, 1} when
2989 * - encoding: May be used to signal the framerate of CFR content to an
2992 AVRational framerate;
2995 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2996 * - encoding: unused.
2997 * - decoding: Set by libavcodec before calling get_format()
2999 enum AVPixelFormat sw_pix_fmt;
3002 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3003 * - encoding unused.
3004 * - decoding set by user.
3006 AVRational pkt_timebase;
3010 * - encoding: unused.
3011 * - decoding: set by libavcodec.
3013 const AVCodecDescriptor *codec_descriptor;
3017 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3018 * - encoding: unused
3019 * - decoding: Set by user.
3025 * Current statistics for PTS correction.
3026 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3027 * - encoding: unused
3029 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3030 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3031 int64_t pts_correction_last_pts; /// PTS of the last frame
3032 int64_t pts_correction_last_dts; /// DTS of the last frame
3035 * Character encoding of the input subtitles file.
3036 * - decoding: set by user
3037 * - encoding: unused
3042 * Subtitles character encoding mode. Formats or codecs might be adjusting
3043 * this setting (if they are doing the conversion themselves for instance).
3044 * - decoding: set by libavcodec
3045 * - encoding: unused
3047 int sub_charenc_mode;
3048 #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)
3049 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3050 #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
3053 * Skip processing alpha if supported by codec.
3054 * Note that if the format uses pre-multiplied alpha (common with VP6,
3055 * and recommended due to better video quality/compression)
3056 * the image will look as if alpha-blended onto a black background.
3057 * However for formats that do not use pre-multiplied alpha
3058 * there might be serious artefacts (though e.g. libswscale currently
3059 * assumes pre-multiplied alpha anyway).
3061 * - decoding: set by user
3062 * - encoding: unused
3067 * Number of samples to skip after a discontinuity
3068 * - decoding: unused
3069 * - encoding: set by libavcodec
3073 #if !FF_API_DEBUG_MV
3075 * debug motion vectors
3076 * - encoding: Set by user.
3077 * - decoding: Set by user.
3080 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3081 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3082 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3086 * custom intra quantization matrix
3087 * - encoding: Set by user, can be NULL.
3088 * - decoding: unused.
3090 uint16_t *chroma_intra_matrix;
3093 * dump format separator.
3094 * can be ", " or "\n " or anything else
3095 * - encoding: Set by user.
3096 * - decoding: Set by user.
3098 uint8_t *dump_separator;
3101 * ',' separated list of allowed decoders.
3102 * If NULL then all are allowed
3103 * - encoding: unused
3104 * - decoding: set by user
3106 char *codec_whitelist;
3109 * Properties of the stream that gets decoded
3110 * - encoding: unused
3111 * - decoding: set by libavcodec
3113 unsigned properties;
3114 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3115 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3118 * Additional data associated with the entire coded stream.
3120 * - decoding: unused
3121 * - encoding: may be set by libavcodec after avcodec_open2().
3123 AVPacketSideData *coded_side_data;
3124 int nb_coded_side_data;
3127 * A reference to the AVHWFramesContext describing the input (for encoding)
3128 * or output (decoding) frames. The reference is set by the caller and
3129 * afterwards owned (and freed) by libavcodec - it should never be read by
3130 * the caller after being set.
3132 * - decoding: This field should be set by the caller from the get_format()
3133 * callback. The previous reference (if any) will always be
3134 * unreffed by libavcodec before the get_format() call.
3136 * If the default get_buffer2() is used with a hwaccel pixel
3137 * format, then this AVHWFramesContext will be used for
3138 * allocating the frame buffers.
3140 * - encoding: For hardware encoders configured to use a hwaccel pixel
3141 * format, this field should be set by the caller to a reference
3142 * to the AVHWFramesContext describing input frames.
3143 * AVHWFramesContext.format must be equal to
3144 * AVCodecContext.pix_fmt.
3146 * This field should be set before avcodec_open2() is called.
3148 AVBufferRef *hw_frames_ctx;
3151 * Control the form of AVSubtitle.rects[N]->ass
3152 * - decoding: set by user
3153 * - encoding: unused
3155 int sub_text_format;
3156 #define FF_SUB_TEXT_FMT_ASS 0
3157 #if FF_API_ASS_TIMING
3158 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3162 * Audio only. The amount of padding (in samples) appended by the encoder to
3163 * the end of the audio. I.e. this number of decoded samples must be
3164 * discarded by the caller from the end of the stream to get the original
3165 * audio without any trailing padding.
3167 * - decoding: unused
3168 * - encoding: unused
3170 int trailing_padding;
3173 * The number of pixels per image to maximally accept.
3175 * - decoding: set by user
3176 * - encoding: set by user
3181 * A reference to the AVHWDeviceContext describing the device which will
3182 * be used by a hardware encoder/decoder. The reference is set by the
3183 * caller and afterwards owned (and freed) by libavcodec.
3185 * This should be used if either the codec device does not require
3186 * hardware frames or any that are used are to be allocated internally by
3187 * libavcodec. If the user wishes to supply any of the frames used as
3188 * encoder input or decoder output then hw_frames_ctx should be used
3189 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3190 * field will be ignored while decoding the associated stream segment, but
3191 * may again be used on a following one after another get_format() call.
3193 * For both encoders and decoders this field should be set before
3194 * avcodec_open2() is called and must not be written to thereafter.
3196 * Note that some decoders may require this field to be set initially in
3197 * order to support hw_frames_ctx at all - in that case, all frames
3198 * contexts used must be created on the same device.
3200 AVBufferRef *hw_device_ctx;
3203 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3204 * decoding (if active).
3205 * - encoding: unused
3206 * - decoding: Set by user (either before avcodec_open2(), or in the
3207 * AVCodecContext.get_format callback)
3212 * Video decoding only. Certain video codecs support cropping, meaning that
3213 * only a sub-rectangle of the decoded frame is intended for display. This
3214 * option controls how cropping is handled by libavcodec.
3216 * When set to 1 (the default), libavcodec will apply cropping internally.
3217 * I.e. it will modify the output frame width/height fields and offset the
3218 * data pointers (only by as much as possible while preserving alignment, or
3219 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3220 * the frames output by the decoder refer only to the cropped area. The
3221 * crop_* fields of the output frames will be zero.
3223 * When set to 0, the width/height fields of the output frames will be set
3224 * to the coded dimensions and the crop_* fields will describe the cropping
3225 * rectangle. Applying the cropping is left to the caller.
3227 * @warning When hardware acceleration with opaque output frames is used,
3228 * libavcodec is unable to apply cropping from the top/left border.
3230 * @note when this option is set to zero, the width/height fields of the
3231 * AVCodecContext and output AVFrames have different meanings. The codec
3232 * context fields store display dimensions (with the coded dimensions in
3233 * coded_width/height), while the frame fields store the coded dimensions
3234 * (with the display dimensions being determined by the crop_* fields).
3239 #if FF_API_CODEC_GET_SET
3241 * Accessors for some AVCodecContext fields. These used to be provided for ABI
3242 * compatibility, and do not need to be used anymore.
3244 attribute_deprecated
3245 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3246 attribute_deprecated
3247 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3249 attribute_deprecated
3250 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3251 attribute_deprecated
3252 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3254 attribute_deprecated
3255 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3258 attribute_deprecated
3259 int av_codec_get_lowres(const AVCodecContext *avctx);
3260 attribute_deprecated
3261 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3264 attribute_deprecated
3265 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3266 attribute_deprecated
3267 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3269 attribute_deprecated
3270 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3271 attribute_deprecated
3272 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3278 typedef struct AVProfile {
3280 const char *name; ///< short name for the profile
3285 * The codec supports this format via the hw_device_ctx interface.
3287 * When selecting this format, AVCodecContext.hw_device_ctx should
3288 * have been set to a device of the specified type before calling
3291 AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX = 0x01,
3293 * The codec supports this format via the hw_frames_ctx interface.
3295 * When selecting this format for a decoder,
3296 * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3297 * context inside the get_format() callback. The frames context
3298 * must have been created on a device of the specified type.
3300 AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX = 0x02,
3302 * The codec supports this format by some internal method.
3304 * This format can be selected without any additional configuration -
3305 * no device or frames context is required.
3307 AV_CODEC_HW_CONFIG_METHOD_INTERNAL = 0x04,
3309 * The codec supports this format by some ad-hoc method.
3311 * Additional settings and/or function calls are required. See the
3312 * codec-specific documentation for details. (Methods requiring
3313 * this sort of configuration are deprecated and others should be
3314 * used in preference.)
3316 AV_CODEC_HW_CONFIG_METHOD_AD_HOC = 0x08,
3319 typedef struct AVCodecHWConfig {
3321 * A hardware pixel format which the codec can use.
3323 enum AVPixelFormat pix_fmt;
3325 * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3326 * setup methods which can be used with this configuration.
3330 * The device type associated with the configuration.
3332 * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3333 * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3335 enum AVHWDeviceType device_type;
3338 typedef struct AVCodecDefault AVCodecDefault;
3345 typedef struct AVCodec {
3347 * Name of the codec implementation.
3348 * The name is globally unique among encoders and among decoders (but an
3349 * encoder and a decoder can share the same name).
3350 * This is the primary way to find a codec from the user perspective.
3354 * Descriptive name for the codec, meant to be more human readable than name.
3355 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3357 const char *long_name;
3358 enum AVMediaType type;
3361 * Codec capabilities.
3362 * see AV_CODEC_CAP_*
3365 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3366 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3367 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3368 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3369 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3370 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3371 const AVClass *priv_class; ///< AVClass for the private context
3372 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3374 /*****************************************************************
3375 * No fields below this line are part of the public API. They
3376 * may not be used outside of libavcodec and can be changed and
3378 * New public fields should be added right above.
3379 *****************************************************************
3382 struct AVCodec *next;
3384 * @name Frame-level threading support functions
3388 * If defined, called on thread contexts when they are created.
3389 * If the codec allocates writable tables in init(), re-allocate them here.
3390 * priv_data will be set to a copy of the original.
3392 int (*init_thread_copy)(AVCodecContext *);
3394 * Copy necessary context variables from a previous thread context to the current one.
3395 * If not defined, the next thread will start automatically; otherwise, the codec
3396 * must call ff_thread_finish_setup().
3398 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3400 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3404 * Private codec-specific defaults.
3406 const AVCodecDefault *defaults;
3409 * Initialize codec static data, called from avcodec_register().
3411 void (*init_static_data)(struct AVCodec *codec);
3413 int (*init)(AVCodecContext *);
3414 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3415 const struct AVSubtitle *sub);
3417 * Encode data to an AVPacket.
3419 * @param avctx codec context
3420 * @param avpkt output AVPacket (may contain a user-provided buffer)
3421 * @param[in] frame AVFrame containing the raw data to be encoded
3422 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3423 * non-empty packet was returned in avpkt.
3424 * @return 0 on success, negative error code on failure
3426 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3427 int *got_packet_ptr);
3428 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3429 int (*close)(AVCodecContext *);
3431 * Encode API with decoupled packet/frame dataflow. The API is the
3432 * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3434 * - never called if the codec is closed or the wrong type,
3435 * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3436 * - only one drain frame is ever passed down,
3438 int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3439 int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3442 * Decode API with decoupled packet/frame dataflow. This function is called
3443 * to get one output frame. It should call ff_decode_get_packet() to obtain
3446 int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
3449 * Will be called when seeking
3451 void (*flush)(AVCodecContext *);
3453 * Internal codec capabilities.
3454 * See FF_CODEC_CAP_* in internal.h
3459 * Decoding only, a comma-separated list of bitstream filters to apply to
3460 * packets before decoding.
3465 * Array of pointers to hardware configurations supported by the codec,
3466 * or NULL if no hardware supported. The array is terminated by a NULL
3469 * The user can only access this field via avcodec_get_hw_config().
3471 const struct AVCodecHWConfigInternal **hw_configs;
3474 #if FF_API_CODEC_GET_SET
3475 attribute_deprecated
3476 int av_codec_get_max_lowres(const AVCodec *codec);
3479 struct MpegEncContext;
3482 * Retrieve supported hardware configurations for a codec.
3484 * Values of index from zero to some maximum return the indexed configuration
3485 * descriptor; all other values return NULL. If the codec does not support
3486 * any hardware configurations then it will always return NULL.
3488 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3491 * @defgroup lavc_hwaccel AVHWAccel
3493 * @note Nothing in this structure should be accessed by the user. At some
3494 * point in future it will not be externally visible at all.
3498 typedef struct AVHWAccel {
3500 * Name of the hardware accelerated codec.
3501 * The name is globally unique among encoders and among decoders (but an
3502 * encoder and a decoder can share the same name).
3507 * Type of codec implemented by the hardware accelerator.
3509 * See AVMEDIA_TYPE_xxx
3511 enum AVMediaType type;
3514 * Codec implemented by the hardware accelerator.
3516 * See AV_CODEC_ID_xxx
3521 * Supported pixel format.
3523 * Only hardware accelerated formats are supported here.
3525 enum AVPixelFormat pix_fmt;
3528 * Hardware accelerated codec capabilities.
3529 * see AV_HWACCEL_CODEC_CAP_*
3533 /*****************************************************************
3534 * No fields below this line are part of the public API. They
3535 * may not be used outside of libavcodec and can be changed and
3537 * New public fields should be added right above.
3538 *****************************************************************
3542 * Allocate a custom buffer
3544 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
3547 * Called at the beginning of each frame or field picture.
3549 * Meaningful frame information (codec specific) is guaranteed to
3550 * be parsed at this point. This function is mandatory.
3552 * Note that buf can be NULL along with buf_size set to 0.
3553 * Otherwise, this means the whole frame is available at this point.
3555 * @param avctx the codec context
3556 * @param buf the frame data buffer base
3557 * @param buf_size the size of the frame in bytes
3558 * @return zero if successful, a negative value otherwise
3560 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3563 * Callback for parameter data (SPS/PPS/VPS etc).
3565 * Useful for hardware decoders which keep persistent state about the
3566 * video parameters, and need to receive any changes to update that state.
3568 * @param avctx the codec context
3569 * @param type the nal unit type
3570 * @param buf the nal unit data buffer
3571 * @param buf_size the size of the nal unit in bytes
3572 * @return zero if successful, a negative value otherwise
3574 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3577 * Callback for each slice.
3579 * Meaningful slice information (codec specific) is guaranteed to
3580 * be parsed at this point. This function is mandatory.
3581 * The only exception is XvMC, that works on MB level.
3583 * @param avctx the codec context
3584 * @param buf the slice data buffer base
3585 * @param buf_size the size of the slice in bytes
3586 * @return zero if successful, a negative value otherwise
3588 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3591 * Called at the end of each frame or field picture.
3593 * The whole picture is parsed at this point and can now be sent
3594 * to the hardware accelerator. This function is mandatory.
3596 * @param avctx the codec context
3597 * @return zero if successful, a negative value otherwise
3599 int (*end_frame)(AVCodecContext *avctx);
3602 * Size of per-frame hardware accelerator private data.
3604 * Private data is allocated with av_mallocz() before
3605 * AVCodecContext.get_buffer() and deallocated after
3606 * AVCodecContext.release_buffer().
3608 int frame_priv_data_size;
3611 * Called for every Macroblock in a slice.
3613 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3614 * Instead of decoding to raw picture, MB parameters are
3615 * stored in an array provided by the video driver.
3617 * @param s the mpeg context
3619 void (*decode_mb)(struct MpegEncContext *s);
3622 * Initialize the hwaccel private data.
3624 * This will be called from ff_get_format(), after hwaccel and
3625 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3628 int (*init)(AVCodecContext *avctx);
3631 * Uninitialize the hwaccel private data.
3633 * This will be called from get_format() or avcodec_close(), after hwaccel
3634 * and hwaccel_context are already uninitialized.
3636 int (*uninit)(AVCodecContext *avctx);
3639 * Size of the private data to allocate in
3640 * AVCodecInternal.hwaccel_priv_data.
3645 * Internal hwaccel capabilities.
3650 * Fill the given hw_frames context with current codec parameters. Called
3651 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3654 * This CAN be called before AVHWAccel.init is called, and you must assume
3655 * that avctx->hwaccel_priv_data is invalid.
3657 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3661 * HWAccel is experimental and is thus avoided in favor of non experimental
3664 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3667 * Hardware acceleration should be used for decoding even if the codec level
3668 * used is unknown or higher than the maximum supported level reported by the
3671 * It's generally a good idea to pass this flag unless you have a specific
3672 * reason not to, as hardware tends to under-report supported levels.
3674 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3677 * Hardware acceleration can output YUV pixel formats with a different chroma
3678 * sampling than 4:2:0 and/or other than 8 bits per component.
3680 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3683 * Hardware acceleration should still be attempted for decoding when the
3684 * codec profile does not match the reported capabilities of the hardware.
3686 * For example, this can be used to try to decode baseline profile H.264
3687 * streams in hardware - it will often succeed, because many streams marked
3688 * as baseline profile actually conform to constrained baseline profile.
3690 * @warning If the stream is actually not supported then the behaviour is
3691 * undefined, and may include returning entirely incorrect output
3692 * while indicating success.
3694 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3700 #if FF_API_AVPICTURE
3702 * @defgroup lavc_picture AVPicture
3704 * Functions for working with AVPicture
3709 * Picture data structure.
3711 * Up to four components can be stored into it, the last component is
3713 * @deprecated use AVFrame or imgutils functions instead
3715 typedef struct AVPicture {
3716 attribute_deprecated
3717 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3718 attribute_deprecated
3719 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3727 enum AVSubtitleType {
3730 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3733 * Plain text, the text field must be set by the decoder and is
3734 * authoritative. ass and pict fields may contain approximations.
3739 * Formatted text, the ass field must be set by the decoder and is
3740 * authoritative. pict and text fields may contain approximations.
3745 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3747 typedef struct AVSubtitleRect {
3748 int x; ///< top left corner of pict, undefined when pict is not set
3749 int y; ///< top left corner of pict, undefined when pict is not set
3750 int w; ///< width of pict, undefined when pict is not set
3751 int h; ///< height of pict, undefined when pict is not set
3752 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3754 #if FF_API_AVPICTURE
3756 * @deprecated unused
3758 attribute_deprecated
3762 * data+linesize for the bitmap of this subtitle.
3763 * Can be set for text/ass as well once they are rendered.
3768 enum AVSubtitleType type;
3770 char *text; ///< 0 terminated plain UTF-8 text
3773 * 0 terminated ASS/SSA compatible event line.
3774 * The presentation of this is unaffected by the other values in this
3782 typedef struct AVSubtitle {
3783 uint16_t format; /* 0 = graphics */
3784 uint32_t start_display_time; /* relative to packet pts, in ms */
3785 uint32_t end_display_time; /* relative to packet pts, in ms */
3787 AVSubtitleRect **rects;
3788 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3792 * This struct describes the properties of an encoded stream.
3794 * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3795 * be allocated with avcodec_parameters_alloc() and freed with
3796 * avcodec_parameters_free().
3798 typedef struct AVCodecParameters {
3800 * General type of the encoded data.
3802 enum AVMediaType codec_type;
3804 * Specific type of the encoded data (the codec used).
3806 enum AVCodecID codec_id;
3808 * Additional information about the codec (corresponds to the AVI FOURCC).
3813 * Extra binary data needed for initializing the decoder, codec-dependent.
3815 * Must be allocated with av_malloc() and will be freed by
3816 * avcodec_parameters_free(). The allocated size of extradata must be at
3817 * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3822 * Size of the extradata content in bytes.
3827 * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3828 * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3833 * The average bitrate of the encoded data (in bits per second).
3838 * The number of bits per sample in the codedwords.
3840 * This is basically the bitrate per sample. It is mandatory for a bunch of
3841 * formats to actually decode them. It's the number of bits for one sample in
3842 * the actual coded bitstream.
3844 * This could be for example 4 for ADPCM
3845 * For PCM formats this matches bits_per_raw_sample
3848 int bits_per_coded_sample;
3851 * This is the number of valid bits in each output sample. If the
3852 * sample format has more bits, the least significant bits are additional
3853 * padding bits, which are always 0. Use right shifts to reduce the sample
3854 * to its actual size. For example, audio formats with 24 bit samples will
3855 * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3856 * To get the original sample use "(int32_t)sample >> 8"."
3858 * For ADPCM this might be 12 or 16 or similar
3861 int bits_per_raw_sample;
3864 * Codec-specific bitstream restrictions that the stream conforms to.
3870 * Video only. The dimensions of the video frame in pixels.
3876 * Video only. The aspect ratio (width / height) which a single pixel
3877 * should have when displayed.
3879 * When the aspect ratio is unknown / undefined, the numerator should be
3880 * set to 0 (the denominator may have any value).
3882 AVRational sample_aspect_ratio;
3885 * Video only. The order of the fields in interlaced video.
3887 enum AVFieldOrder field_order;
3890 * Video only. Additional colorspace characteristics.
3892 enum AVColorRange color_range;
3893 enum AVColorPrimaries color_primaries;
3894 enum AVColorTransferCharacteristic color_trc;
3895 enum AVColorSpace color_space;
3896 enum AVChromaLocation chroma_location;
3899 * Video only. Number of delayed frames.
3904 * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3905 * unknown or unspecified, otherwise the number of bits set must be equal to
3906 * the channels field.
3908 uint64_t channel_layout;
3910 * Audio only. The number of audio channels.
3914 * Audio only. The number of audio samples per second.
3918 * Audio only. The number of bytes per coded audio frame, required by some
3921 * Corresponds to nBlockAlign in WAVEFORMATEX.
3925 * Audio only. Audio frame size, if known. Required by some formats to be static.
3930 * Audio only. The amount of padding (in samples) inserted by the encoder at
3931 * the beginning of the audio. I.e. this number of leading decoded samples
3932 * must be discarded by the caller to get the original audio without leading
3935 int initial_padding;
3937 * Audio only. The amount of padding (in samples) appended by the encoder to
3938 * the end of the audio. I.e. this number of decoded samples must be
3939 * discarded by the caller from the end of the stream to get the original
3940 * audio without any trailing padding.
3942 int trailing_padding;
3944 * Audio only. Number of samples to skip after a discontinuity.
3947 } AVCodecParameters;
3950 * If c is NULL, returns the first registered codec,
3951 * if c is non-NULL, returns the next registered codec after c,
3952 * or NULL if c is the last one.
3954 AVCodec *av_codec_next(const AVCodec *c);
3957 * Return the LIBAVCODEC_VERSION_INT constant.
3959 unsigned avcodec_version(void);
3962 * Return the libavcodec build-time configuration.
3964 const char *avcodec_configuration(void);
3967 * Return the libavcodec license.
3969 const char *avcodec_license(void);
3972 * Register the codec codec and initialize libavcodec.
3974 * @warning either this function or avcodec_register_all() must be called
3975 * before any other libavcodec functions.
3977 * @see avcodec_register_all()
3979 void avcodec_register(AVCodec *codec);
3982 * Register all the codecs, parsers and bitstream filters which were enabled at
3983 * configuration time. If you do not call this function you can select exactly
3984 * which formats you want to support, by using the individual registration
3987 * @see avcodec_register
3988 * @see av_register_codec_parser
3989 * @see av_register_bitstream_filter
3991 void avcodec_register_all(void);
3994 * Allocate an AVCodecContext and set its fields to default values. The
3995 * resulting struct should be freed with avcodec_free_context().
3997 * @param codec if non-NULL, allocate private data and initialize defaults
3998 * for the given codec. It is illegal to then call avcodec_open2()
3999 * with a different codec.
4000 * If NULL, then the codec-specific defaults won't be initialized,
4001 * which may result in suboptimal default settings (this is
4002 * important mainly for encoders, e.g. libx264).
4004 * @return An AVCodecContext filled with default values or NULL on failure.
4006 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
4009 * Free the codec context and everything associated with it and write NULL to
4010 * the provided pointer.
4012 void avcodec_free_context(AVCodecContext **avctx);
4014 #if FF_API_GET_CONTEXT_DEFAULTS
4016 * @deprecated This function should not be used, as closing and opening a codec
4017 * context multiple time is not supported. A new codec context should be
4018 * allocated for each new use.
4020 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
4024 * Get the AVClass for AVCodecContext. It can be used in combination with
4025 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4027 * @see av_opt_find().
4029 const AVClass *avcodec_get_class(void);
4031 #if FF_API_COPY_CONTEXT
4033 * Get the AVClass for AVFrame. It can be used in combination with
4034 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4036 * @see av_opt_find().
4038 const AVClass *avcodec_get_frame_class(void);
4041 * Get the AVClass for AVSubtitleRect. It can be used in combination with
4042 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4044 * @see av_opt_find().
4046 const AVClass *avcodec_get_subtitle_rect_class(void);
4049 * Copy the settings of the source AVCodecContext into the destination
4050 * AVCodecContext. The resulting destination codec context will be
4051 * unopened, i.e. you are required to call avcodec_open2() before you
4052 * can use this AVCodecContext to decode/encode video/audio data.
4054 * @param dest target codec context, should be initialized with
4055 * avcodec_alloc_context3(NULL), but otherwise uninitialized
4056 * @param src source codec context
4057 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4059 * @deprecated The semantics of this function are ill-defined and it should not
4060 * be used. If you need to transfer the stream parameters from one codec context
4061 * to another, use an intermediate AVCodecParameters instance and the
4062 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4065 attribute_deprecated
4066 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
4070 * Allocate a new AVCodecParameters and set its fields to default values
4071 * (unknown/invalid/0). The returned struct must be freed with
4072 * avcodec_parameters_free().
4074 AVCodecParameters *avcodec_parameters_alloc(void);
4077 * Free an AVCodecParameters instance and everything associated with it and
4078 * write NULL to the supplied pointer.
4080 void avcodec_parameters_free(AVCodecParameters **par);
4083 * Copy the contents of src to dst. Any allocated fields in dst are freed and
4084 * replaced with newly allocated duplicates of the corresponding fields in src.
4086 * @return >= 0 on success, a negative AVERROR code on failure.
4088 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
4091 * Fill the parameters struct based on the values from the supplied codec
4092 * context. Any allocated fields in par are freed and replaced with duplicates
4093 * of the corresponding fields in codec.
4095 * @return >= 0 on success, a negative AVERROR code on failure
4097 int avcodec_parameters_from_context(AVCodecParameters *par,
4098 const AVCodecContext *codec);
4101 * Fill the codec context based on the values from the supplied codec
4102 * parameters. Any allocated fields in codec that have a corresponding field in
4103 * par are freed and replaced with duplicates of the corresponding field in par.
4104 * Fields in codec that do not have a counterpart in par are not touched.
4106 * @return >= 0 on success, a negative AVERROR code on failure.
4108 int avcodec_parameters_to_context(AVCodecContext *codec,
4109 const AVCodecParameters *par);
4112 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4113 * function the context has to be allocated with avcodec_alloc_context3().
4115 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4116 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4117 * retrieving a codec.
4119 * @warning This function is not thread safe!
4121 * @note Always call this function before using decoding routines (such as
4122 * @ref avcodec_receive_frame()).
4125 * avcodec_register_all();
4126 * av_dict_set(&opts, "b", "2.5M", 0);
4127 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4131 * context = avcodec_alloc_context3(codec);
4133 * if (avcodec_open2(context, codec, opts) < 0)
4137 * @param avctx The context to initialize.
4138 * @param codec The codec to open this context for. If a non-NULL codec has been
4139 * previously passed to avcodec_alloc_context3() or
4140 * for this context, then this parameter MUST be either NULL or
4141 * equal to the previously passed codec.
4142 * @param options A dictionary filled with AVCodecContext and codec-private options.
4143 * On return this object will be filled with options that were not found.
4145 * @return zero on success, a negative value on error
4146 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4147 * av_dict_set(), av_opt_find().
4149 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4152 * Close a given AVCodecContext and free all the data associated with it
4153 * (but not the AVCodecContext itself).
4155 * Calling this function on an AVCodecContext that hasn't been opened will free
4156 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4157 * codec. Subsequent calls will do nothing.
4159 * @note Do not use this function. Use avcodec_free_context() to destroy a
4160 * codec context (either open or closed). Opening and closing a codec context
4161 * multiple times is not supported anymore -- use multiple codec contexts
4164 int avcodec_close(AVCodecContext *avctx);
4167 * Free all allocated data in the given subtitle struct.
4169 * @param sub AVSubtitle to free.
4171 void avsubtitle_free(AVSubtitle *sub);
4178 * @addtogroup lavc_packet
4183 * Allocate an AVPacket and set its fields to default values. The resulting
4184 * struct must be freed using av_packet_free().
4186 * @return An AVPacket filled with default values or NULL on failure.
4188 * @note this only allocates the AVPacket itself, not the data buffers. Those
4189 * must be allocated through other means such as av_new_packet.
4191 * @see av_new_packet
4193 AVPacket *av_packet_alloc(void);
4196 * Create a new packet that references the same data as src.
4198 * This is a shortcut for av_packet_alloc()+av_packet_ref().
4200 * @return newly created AVPacket on success, NULL on error.
4202 * @see av_packet_alloc
4203 * @see av_packet_ref
4205 AVPacket *av_packet_clone(const AVPacket *src);
4208 * Free the packet, if the packet is reference counted, it will be
4209 * unreferenced first.
4211 * @param pkt packet to be freed. The pointer will be set to NULL.
4212 * @note passing NULL is a no-op.
4214 void av_packet_free(AVPacket **pkt);
4217 * Initialize optional fields of a packet with default values.
4219 * Note, this does not touch the data and size members, which have to be
4220 * initialized separately.
4224 void av_init_packet(AVPacket *pkt);
4227 * Allocate the payload of a packet and initialize its fields with
4231 * @param size wanted payload size
4232 * @return 0 if OK, AVERROR_xxx otherwise
4234 int av_new_packet(AVPacket *pkt, int size);
4237 * Reduce packet size, correctly zeroing padding
4240 * @param size new size
4242 void av_shrink_packet(AVPacket *pkt, int size);
4245 * Increase packet size, correctly zeroing padding
4248 * @param grow_by number of bytes by which to increase the size of the packet
4250 int av_grow_packet(AVPacket *pkt, int grow_by);
4253 * Initialize a reference-counted packet from av_malloc()ed data.
4255 * @param pkt packet to be initialized. This function will set the data, size,
4256 * buf and destruct fields, all others are left untouched.
4257 * @param data Data allocated by av_malloc() to be used as packet data. If this
4258 * function returns successfully, the data is owned by the underlying AVBuffer.
4259 * The caller may not access the data through other means.
4260 * @param size size of data in bytes, without the padding. I.e. the full buffer
4261 * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4263 * @return 0 on success, a negative AVERROR on error
4265 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
4267 #if FF_API_AVPACKET_OLD_API
4269 * @warning This is a hack - the packet memory allocation stuff is broken. The
4270 * packet is allocated if it was not really allocated.
4272 * @deprecated Use av_packet_ref
4274 attribute_deprecated
4275 int av_dup_packet(AVPacket *pkt);
4277 * Copy packet, including contents
4279 * @return 0 on success, negative AVERROR on fail
4281 * @deprecated Use av_packet_ref
4283 attribute_deprecated
4284 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4287 * Copy packet side data
4289 * @return 0 on success, negative AVERROR on fail
4291 * @deprecated Use av_packet_copy_props
4293 attribute_deprecated
4294 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4299 * @deprecated Use av_packet_unref
4301 * @param pkt packet to free
4303 attribute_deprecated
4304 void av_free_packet(AVPacket *pkt);
4307 * Allocate new information of a packet.
4310 * @param type side information type
4311 * @param size side information size
4312 * @return pointer to fresh allocated data or NULL otherwise
4314 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4318 * Wrap an existing array as a packet side data.
4321 * @param type side information type
4322 * @param data the side data array. It must be allocated with the av_malloc()
4323 * family of functions. The ownership of the data is transferred to
4325 * @param size side information size
4326 * @return a non-negative number on success, a negative AVERROR code on
4327 * failure. On failure, the packet is unchanged and the data remains
4328 * owned by the caller.
4330 int av_packet_add_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4331 uint8_t *data, size_t size);
4334 * Shrink the already allocated side data buffer
4337 * @param type side information type
4338 * @param size new side information size
4339 * @return 0 on success, < 0 on failure
4341 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4345 * Get side information from packet.
4348 * @param type desired side information type
4349 * @param size pointer for side information size to store (optional)
4350 * @return pointer to data if present or NULL otherwise
4352 uint8_t* av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type,
4355 #if FF_API_MERGE_SD_API
4356 attribute_deprecated
4357 int av_packet_merge_side_data(AVPacket *pkt);
4359 attribute_deprecated
4360 int av_packet_split_side_data(AVPacket *pkt);
4363 const char *av_packet_side_data_name(enum AVPacketSideDataType type);
4366 * Pack a dictionary for use in side_data.
4368 * @param dict The dictionary to pack.
4369 * @param size pointer to store the size of the returned data
4370 * @return pointer to data if successful, NULL otherwise
4372 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size);
4374 * Unpack a dictionary from side_data.
4376 * @param data data from side_data
4377 * @param size size of the data
4378 * @param dict the metadata storage dictionary
4379 * @return 0 on success, < 0 on failure
4381 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4385 * Convenience function to free all the side data stored.
4386 * All the other fields stay untouched.
4390 void av_packet_free_side_data(AVPacket *pkt);
4393 * Setup a new reference to the data described by a given packet
4395 * If src is reference-counted, setup dst as a new reference to the
4396 * buffer in src. Otherwise allocate a new buffer in dst and copy the
4397 * data from src into it.
4399 * All the other fields are copied from src.
4401 * @see av_packet_unref
4403 * @param dst Destination packet
4404 * @param src Source packet
4406 * @return 0 on success, a negative AVERROR on error.
4408 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4413 * Unreference the buffer referenced by the packet and reset the
4414 * remaining packet fields to their default values.
4416 * @param pkt The packet to be unreferenced.
4418 void av_packet_unref(AVPacket *pkt);
4421 * Move every field in src to dst and reset src.
4423 * @see av_packet_unref
4425 * @param src Source packet, will be reset
4426 * @param dst Destination packet
4428 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
4431 * Copy only "properties" fields from src to dst.
4433 * Properties for the purpose of this function are all the fields
4434 * beside those related to the packet data (buf, data, size)
4436 * @param dst Destination packet
4437 * @param src Source packet
4439 * @return 0 on success AVERROR on failure.
4441 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4444 * Convert valid timing fields (timestamps / durations) in a packet from one
4445 * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4448 * @param pkt packet on which the conversion will be performed
4449 * @param tb_src source timebase, in which the timing fields in pkt are
4451 * @param tb_dst destination timebase, to which the timing fields will be
4454 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4461 * @addtogroup lavc_decoding
4466 * Find a registered decoder with a matching codec ID.
4468 * @param id AVCodecID of the requested decoder
4469 * @return A decoder if one was found, NULL otherwise.
4471 AVCodec *avcodec_find_decoder(enum AVCodecID id);
4474 * Find a registered decoder with the specified name.
4476 * @param name name of the requested decoder
4477 * @return A decoder if one was found, NULL otherwise.
4479 AVCodec *avcodec_find_decoder_by_name(const char *name);
4482 * The default callback for AVCodecContext.get_buffer2(). It is made public so
4483 * it can be called by custom get_buffer2() implementations for decoders without
4484 * AV_CODEC_CAP_DR1 set.
4486 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
4489 * Modify width and height values so that they will result in a memory
4490 * buffer that is acceptable for the codec if you do not use any horizontal
4493 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4495 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
4498 * Modify width and height values so that they will result in a memory
4499 * buffer that is acceptable for the codec if you also ensure that all
4500 * line sizes are a multiple of the respective linesize_align[i].
4502 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4504 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
4505 int linesize_align[AV_NUM_DATA_POINTERS]);
4508 * Converts AVChromaLocation to swscale x/y chroma position.
4510 * The positions represent the chroma (0,0) position in a coordinates system
4511 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4513 * @param xpos horizontal chroma sample position
4514 * @param ypos vertical chroma sample position
4516 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4519 * Converts swscale x/y chroma position to AVChromaLocation.
4521 * The positions represent the chroma (0,0) position in a coordinates system
4522 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4524 * @param xpos horizontal chroma sample position
4525 * @param ypos vertical chroma sample position
4527 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4530 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4532 * Some decoders may support multiple frames in a single AVPacket. Such
4533 * decoders would then just decode the first frame and the return value would be
4534 * less than the packet size. In this case, avcodec_decode_audio4 has to be
4535 * called again with an AVPacket containing the remaining data in order to
4536 * decode the second frame, etc... Even if no frames are returned, the packet
4537 * needs to be fed to the decoder with remaining data until it is completely
4538 * consumed or an error occurs.
4540 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4541 * and output. This means that for some packets they will not immediately
4542 * produce decoded output and need to be flushed at the end of decoding to get
4543 * all the decoded data. Flushing is done by calling this function with packets
4544 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4545 * returning samples. It is safe to flush even those decoders that are not
4546 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4548 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4549 * larger than the actual read bytes because some optimized bitstream
4550 * readers read 32 or 64 bits at once and could read over the end.
4552 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4553 * before packets may be fed to the decoder.
4555 * @param avctx the codec context
4556 * @param[out] frame The AVFrame in which to store decoded audio samples.
4557 * The decoder will allocate a buffer for the decoded frame by
4558 * calling the AVCodecContext.get_buffer2() callback.
4559 * When AVCodecContext.refcounted_frames is set to 1, the frame is
4560 * reference counted and the returned reference belongs to the
4561 * caller. The caller must release the frame using av_frame_unref()
4562 * when the frame is no longer needed. The caller may safely write
4563 * to the frame if av_frame_is_writable() returns 1.
4564 * When AVCodecContext.refcounted_frames is set to 0, the returned
4565 * reference belongs to the decoder and is valid only until the
4566 * next call to this function or until closing or flushing the
4567 * decoder. The caller may not write to it.
4568 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4569 * non-zero. Note that this field being set to zero
4570 * does not mean that an error has occurred. For
4571 * decoders with AV_CODEC_CAP_DELAY set, no given decode
4572 * call is guaranteed to produce a frame.
4573 * @param[in] avpkt The input AVPacket containing the input buffer.
4574 * At least avpkt->data and avpkt->size should be set. Some
4575 * decoders might also require additional fields to be set.
4576 * @return A negative error code is returned if an error occurred during
4577 * decoding, otherwise the number of bytes consumed from the input
4578 * AVPacket is returned.
4580 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4582 attribute_deprecated
4583 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
4584 int *got_frame_ptr, const AVPacket *avpkt);
4587 * Decode the video frame of size avpkt->size from avpkt->data into picture.
4588 * Some decoders may support multiple frames in a single AVPacket, such
4589 * decoders would then just decode the first frame.
4591 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4592 * the actual read bytes because some optimized bitstream readers read 32 or 64
4593 * bits at once and could read over the end.
4595 * @warning The end of the input buffer buf should be set to 0 to ensure that
4596 * no overreading happens for damaged MPEG streams.
4598 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4599 * between input and output, these need to be fed with avpkt->data=NULL,
4600 * avpkt->size=0 at the end to return the remaining frames.
4602 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4603 * before packets may be fed to the decoder.
4605 * @param avctx the codec context
4606 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4607 * Use av_frame_alloc() to get an AVFrame. The codec will
4608 * allocate memory for the actual bitmap by calling the
4609 * AVCodecContext.get_buffer2() callback.
4610 * When AVCodecContext.refcounted_frames is set to 1, the frame is
4611 * reference counted and the returned reference belongs to the
4612 * caller. The caller must release the frame using av_frame_unref()
4613 * when the frame is no longer needed. The caller may safely write
4614 * to the frame if av_frame_is_writable() returns 1.
4615 * When AVCodecContext.refcounted_frames is set to 0, the returned
4616 * reference belongs to the decoder and is valid only until the
4617 * next call to this function or until closing or flushing the
4618 * decoder. The caller may not write to it.
4620 * @param[in] avpkt The input AVPacket containing the input buffer.
4621 * You can create such packet with av_init_packet() and by then setting
4622 * data and size, some decoders might in addition need other fields like
4623 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4625 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4626 * @return On error a negative value is returned, otherwise the number of bytes
4627 * used or zero if no frame could be decompressed.
4629 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4631 attribute_deprecated
4632 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4633 int *got_picture_ptr,
4634 const AVPacket *avpkt);
4637 * Decode a subtitle message.
4638 * Return a negative value on error, otherwise return the number of bytes used.
4639 * If no subtitle could be decompressed, got_sub_ptr is zero.
4640 * Otherwise, the subtitle is stored in *sub.
4641 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4642 * simplicity, because the performance difference is expect to be negligible
4643 * and reusing a get_buffer written for video codecs would probably perform badly
4644 * due to a potentially very different allocation pattern.
4646 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4647 * and output. This means that for some packets they will not immediately
4648 * produce decoded output and need to be flushed at the end of decoding to get
4649 * all the decoded data. Flushing is done by calling this function with packets
4650 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4651 * returning subtitles. It is safe to flush even those decoders that are not
4652 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4654 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4655 * before packets may be fed to the decoder.
4657 * @param avctx the codec context
4658 * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4659 * must be freed with avsubtitle_free if *got_sub_ptr is set.
4660 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4661 * @param[in] avpkt The input AVPacket containing the input buffer.
4663 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
4668 * Supply raw packet data as input to a decoder.
4670 * Internally, this call will copy relevant AVCodecContext fields, which can
4671 * influence decoding per-packet, and apply them when the packet is actually
4672 * decoded. (For example AVCodecContext.skip_frame, which might direct the
4673 * decoder to drop the frame contained by the packet sent with this function.)
4675 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4676 * larger than the actual read bytes because some optimized bitstream
4677 * readers read 32 or 64 bits at once and could read over the end.
4679 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4680 * on the same AVCodecContext. It will return unexpected results now
4681 * or in future libavcodec versions.
4683 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4684 * before packets may be fed to the decoder.
4686 * @param avctx codec context
4687 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4688 * frame, or several complete audio frames.
4689 * Ownership of the packet remains with the caller, and the
4690 * decoder will not write to the packet. The decoder may create
4691 * a reference to the packet data (or copy it if the packet is
4692 * not reference-counted).
4693 * Unlike with older APIs, the packet is always fully consumed,
4694 * and if it contains multiple frames (e.g. some audio codecs),
4695 * will require you to call avcodec_receive_frame() multiple
4696 * times afterwards before you can send a new packet.
4697 * It can be NULL (or an AVPacket with data set to NULL and
4698 * size set to 0); in this case, it is considered a flush
4699 * packet, which signals the end of the stream. Sending the
4700 * first flush packet will return success. Subsequent ones are
4701 * unnecessary and will return AVERROR_EOF. If the decoder
4702 * still has frames buffered, it will return them after sending
4705 * @return 0 on success, otherwise negative error code:
4706 * AVERROR(EAGAIN): input is not accepted in the current state - user
4707 * must read output with avcodec_receive_frame() (once
4708 * all output is read, the packet should be resent, and
4709 * the call will not fail with EAGAIN).
4710 * AVERROR_EOF: the decoder has been flushed, and no new packets can
4711 * be sent to it (also returned if more than 1 flush
4713 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4714 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4715 * other errors: legitimate decoding errors
4717 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4720 * Return decoded output data from a decoder.
4722 * @param avctx codec context
4723 * @param frame This will be set to a reference-counted video or audio
4724 * frame (depending on the decoder type) allocated by the
4725 * decoder. Note that the function will always call
4726 * av_frame_unref(frame) before doing anything else.
4729 * 0: success, a frame was returned
4730 * AVERROR(EAGAIN): output is not available in this state - user must try
4732 * AVERROR_EOF: the decoder has been fully flushed, and there will be
4733 * no more output frames
4734 * AVERROR(EINVAL): codec not opened, or it is an encoder
4735 * other negative values: legitimate decoding errors
4737 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
4740 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4741 * to retrieve buffered output packets.
4743 * @param avctx codec context
4744 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4745 * Ownership of the frame remains with the caller, and the
4746 * encoder will not write to the frame. The encoder may create
4747 * a reference to the frame data (or copy it if the frame is
4748 * not reference-counted).
4749 * It can be NULL, in which case it is considered a flush
4750 * packet. This signals the end of the stream. If the encoder
4751 * still has packets buffered, it will return them after this
4752 * call. Once flushing mode has been entered, additional flush
4753 * packets are ignored, and sending frames will return
4757 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4758 * can have any number of samples.
4759 * If it is not set, frame->nb_samples must be equal to
4760 * avctx->frame_size for all frames except the last.
4761 * The final frame may be smaller than avctx->frame_size.
4762 * @return 0 on success, otherwise negative error code:
4763 * AVERROR(EAGAIN): input is not accepted in the current state - user
4764 * must read output with avcodec_receive_packet() (once
4765 * all output is read, the packet should be resent, and
4766 * the call will not fail with EAGAIN).
4767 * AVERROR_EOF: the encoder has been flushed, and no new frames can
4769 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4770 * decoder, or requires flush
4771 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4772 * other errors: legitimate decoding errors
4774 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4777 * Read encoded data from the encoder.
4779 * @param avctx codec context
4780 * @param avpkt This will be set to a reference-counted packet allocated by the
4781 * encoder. Note that the function will always call
4782 * av_frame_unref(frame) before doing anything else.
4783 * @return 0 on success, otherwise negative error code:
4784 * AVERROR(EAGAIN): output is not available in the current state - user
4785 * must try to send input
4786 * AVERROR_EOF: the encoder has been fully flushed, and there will be
4787 * no more output packets
4788 * AVERROR(EINVAL): codec not opened, or it is an encoder
4789 * other errors: legitimate decoding errors
4791 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4794 * Create and return a AVHWFramesContext with values adequate for hardware
4795 * decoding. This is meant to get called from the get_format callback, and is
4796 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4797 * This API is for decoding with certain hardware acceleration modes/APIs only.
4799 * The returned AVHWFramesContext is not initialized. The caller must do this
4800 * with av_hwframe_ctx_init().
4802 * Calling this function is not a requirement, but makes it simpler to avoid
4803 * codec or hardware API specific details when manually allocating frames.
4805 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
4806 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
4807 * it unnecessary to call this function or having to care about
4808 * AVHWFramesContext initialization at all.
4810 * There are a number of requirements for calling this function:
4812 * - It must be called from get_format with the same avctx parameter that was
4813 * passed to get_format. Calling it outside of get_format is not allowed, and
4814 * can trigger undefined behavior.
4815 * - The function is not always supported (see description of return values).
4816 * Even if this function returns successfully, hwaccel initialization could
4817 * fail later. (The degree to which implementations check whether the stream
4818 * is actually supported varies. Some do this check only after the user's
4819 * get_format callback returns.)
4820 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
4821 * user decides to use a AVHWFramesContext prepared with this API function,
4822 * the user must return the same hw_pix_fmt from get_format.
4823 * - The device_ref passed to this function must support the given hw_pix_fmt.
4824 * - After calling this API function, it is the user's responsibility to
4825 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
4826 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
4827 * before returning from get_format (this is implied by the normal
4828 * AVCodecContext.hw_frames_ctx API rules).
4829 * - The AVHWFramesContext parameters may change every time time get_format is
4830 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
4831 * you are inherently required to go through this process again on every
4833 * - It is perfectly possible to call this function without actually using
4834 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
4835 * previously initialized AVHWFramesContext, and calling this API function
4836 * only to test whether the required frame parameters have changed.
4837 * - Fields that use dynamically allocated values of any kind must not be set
4838 * by the user unless setting them is explicitly allowed by the documentation.
4839 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
4840 * the new free callback must call the potentially set previous free callback.
4841 * This API call may set any dynamically allocated fields, including the free
4844 * The function will set at least the following fields on AVHWFramesContext
4845 * (potentially more, depending on hwaccel API):
4847 * - All fields set by av_hwframe_ctx_alloc().
4848 * - Set the format field to hw_pix_fmt.
4849 * - Set the sw_format field to the most suited and most versatile format. (An
4850 * implication is that this will prefer generic formats over opaque formats
4851 * with arbitrary restrictions, if possible.)
4852 * - Set the width/height fields to the coded frame size, rounded up to the
4853 * API-specific minimum alignment.
4854 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
4855 * field to the number of maximum reference surfaces possible with the codec,
4856 * plus 1 surface for the user to work (meaning the user can safely reference
4857 * at most 1 decoded surface at a time), plus additional buffering introduced
4858 * by frame threading. If the hwaccel does not require pre-allocation, the
4859 * field is left to 0, and the decoder will allocate new surfaces on demand
4861 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
4864 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
4865 * with basic frame parameters set.
4867 * The function is stateless, and does not change the AVCodecContext or the
4868 * device_ref AVHWDeviceContext.
4870 * @param avctx The context which is currently calling get_format, and which
4871 * implicitly contains all state needed for filling the returned
4872 * AVHWFramesContext properly.
4873 * @param device_ref A reference to the AVHWDeviceContext describing the device
4874 * which will be used by the hardware decoder.
4875 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
4876 * @param out_frames_ref On success, set to a reference to an _uninitialized_
4877 * AVHWFramesContext, created from the given device_ref.
4878 * Fields will be set to values required for decoding.
4879 * Not changed if an error is returned.
4880 * @return zero on success, a negative value on error. The following error codes
4881 * have special semantics:
4882 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
4883 * is always manual, or it is a decoder which does not
4884 * support setting AVCodecContext.hw_frames_ctx at all,
4885 * or it is a software format.
4886 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
4887 * this configuration, or the device_ref is not supported
4888 * for the hwaccel referenced by hw_pix_fmt.
4890 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
4891 AVBufferRef *device_ref,
4892 enum AVPixelFormat hw_pix_fmt,
4893 AVBufferRef **out_frames_ref);
4898 * @defgroup lavc_parsing Frame parsing
4902 enum AVPictureStructure {
4903 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
4904 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4905 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4906 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4909 typedef struct AVCodecParserContext {
4911 struct AVCodecParser *parser;
4912 int64_t frame_offset; /* offset of the current frame */
4913 int64_t cur_offset; /* current offset
4914 (incremented by each av_parser_parse()) */
4915 int64_t next_frame_offset; /* offset of the next frame */
4917 int pict_type; /* XXX: Put it back in AVCodecContext. */
4919 * This field is used for proper frame duration computation in lavf.
4920 * It signals, how much longer the frame duration of the current frame
4921 * is compared to normal frame duration.
4923 * frame_duration = (1 + repeat_pict) * time_base
4925 * It is used by codecs like H.264 to display telecined material.
4927 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4928 int64_t pts; /* pts of the current frame */
4929 int64_t dts; /* dts of the current frame */
4934 int fetch_timestamp;
4936 #define AV_PARSER_PTS_NB 4
4937 int cur_frame_start_index;
4938 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
4939 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
4940 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
4943 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4944 #define PARSER_FLAG_ONCE 0x0002
4945 /// Set if the parser has a valid file offset
4946 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4947 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4949 int64_t offset; ///< byte offset from starting packet start
4950 int64_t cur_frame_end[AV_PARSER_PTS_NB];
4953 * Set by parser to 1 for key frames and 0 for non-key frames.
4954 * It is initialized to -1, so if the parser doesn't set this flag,
4955 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4960 #if FF_API_CONVERGENCE_DURATION
4962 * @deprecated unused
4964 attribute_deprecated
4965 int64_t convergence_duration;
4968 // Timestamp generation support:
4970 * Synchronization point for start of timestamp generation.
4972 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4975 * For example, this corresponds to presence of H.264 buffering period
4981 * Offset of the current timestamp against last timestamp sync point in
4982 * units of AVCodecContext.time_base.
4984 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4985 * contain a valid timestamp offset.
4987 * Note that the timestamp of sync point has usually a nonzero
4988 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4989 * the next frame after timestamp sync point will be usually 1.
4991 * For example, this corresponds to H.264 cpb_removal_delay.
4993 int dts_ref_dts_delta;
4996 * Presentation delay of current frame in units of AVCodecContext.time_base.
4998 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4999 * contain valid non-negative timestamp delta (presentation time of a frame
5000 * must not lie in the past).
5002 * This delay represents the difference between decoding and presentation
5003 * time of the frame.
5005 * For example, this corresponds to H.264 dpb_output_delay.
5010 * Position of the packet in file.
5012 * Analogous to cur_frame_pts/dts
5014 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
5017 * Byte position of currently parsed frame in stream.
5022 * Previous frame byte position.
5027 * Duration of the current frame.
5028 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5029 * For all other types, this is in units of AVCodecContext.time_base.
5033 enum AVFieldOrder field_order;
5036 * Indicate whether a picture is coded as a frame, top field or bottom field.
5038 * For example, H.264 field_pic_flag equal to 0 corresponds to
5039 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5040 * equal to 1 and bottom_field_flag equal to 0 corresponds to
5041 * AV_PICTURE_STRUCTURE_TOP_FIELD.
5043 enum AVPictureStructure picture_structure;
5046 * Picture number incremented in presentation or output order.
5047 * This field may be reinitialized at the first picture of a new sequence.
5049 * For example, this corresponds to H.264 PicOrderCnt.
5051 int output_picture_number;
5054 * Dimensions of the decoded video intended for presentation.
5060 * Dimensions of the coded video.
5066 * The format of the coded data, corresponds to enum AVPixelFormat for video
5067 * and for enum AVSampleFormat for audio.
5069 * Note that a decoder can have considerable freedom in how exactly it
5070 * decodes the data, so the format reported here might be different from the
5071 * one returned by a decoder.
5074 } AVCodecParserContext;
5076 typedef struct AVCodecParser {
5077 int codec_ids[5]; /* several codec IDs are permitted */
5079 int (*parser_init)(AVCodecParserContext *s);
5080 /* This callback never returns an error, a negative value means that
5081 * the frame start was in a previous packet. */
5082 int (*parser_parse)(AVCodecParserContext *s,
5083 AVCodecContext *avctx,
5084 const uint8_t **poutbuf, int *poutbuf_size,
5085 const uint8_t *buf, int buf_size);
5086 void (*parser_close)(AVCodecParserContext *s);
5087 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5088 struct AVCodecParser *next;
5091 AVCodecParser *av_parser_next(const AVCodecParser *c);
5093 void av_register_codec_parser(AVCodecParser *parser);
5094 AVCodecParserContext *av_parser_init(int codec_id);
5099 * @param s parser context.
5100 * @param avctx codec context.
5101 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5102 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5103 * @param buf input buffer.
5104 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5105 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5106 To signal EOF, this should be 0 (so that the last frame
5108 * @param pts input presentation timestamp.
5109 * @param dts input decoding timestamp.
5110 * @param pos input byte position in stream.
5111 * @return the number of bytes of the input bitstream used.
5116 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5123 * decode_frame(data, size);
5127 int av_parser_parse2(AVCodecParserContext *s,
5128 AVCodecContext *avctx,
5129 uint8_t **poutbuf, int *poutbuf_size,
5130 const uint8_t *buf, int buf_size,
5131 int64_t pts, int64_t dts,
5135 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5136 * @deprecated use AVBitStreamFilter
5138 int av_parser_change(AVCodecParserContext *s,
5139 AVCodecContext *avctx,
5140 uint8_t **poutbuf, int *poutbuf_size,
5141 const uint8_t *buf, int buf_size, int keyframe);
5142 void av_parser_close(AVCodecParserContext *s);
5150 * @addtogroup lavc_encoding
5155 * Find a registered encoder with a matching codec ID.
5157 * @param id AVCodecID of the requested encoder
5158 * @return An encoder if one was found, NULL otherwise.
5160 AVCodec *avcodec_find_encoder(enum AVCodecID id);
5163 * Find a registered encoder with the specified name.
5165 * @param name name of the requested encoder
5166 * @return An encoder if one was found, NULL otherwise.
5168 AVCodec *avcodec_find_encoder_by_name(const char *name);
5171 * Encode a frame of audio.
5173 * Takes input samples from frame and writes the next output packet, if
5174 * available, to avpkt. The output packet does not necessarily contain data for
5175 * the most recent frame, as encoders can delay, split, and combine input frames
5176 * internally as needed.
5178 * @param avctx codec context
5179 * @param avpkt output AVPacket.
5180 * The user can supply an output buffer by setting
5181 * avpkt->data and avpkt->size prior to calling the
5182 * function, but if the size of the user-provided data is not
5183 * large enough, encoding will fail. If avpkt->data and
5184 * avpkt->size are set, avpkt->destruct must also be set. All
5185 * other AVPacket fields will be reset by the encoder using
5186 * av_init_packet(). If avpkt->data is NULL, the encoder will
5187 * allocate it. The encoder will set avpkt->size to the size
5188 * of the output packet.
5190 * If this function fails or produces no output, avpkt will be
5191 * freed using av_packet_unref().
5192 * @param[in] frame AVFrame containing the raw audio data to be encoded.
5193 * May be NULL when flushing an encoder that has the
5194 * AV_CODEC_CAP_DELAY capability set.
5195 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5196 * can have any number of samples.
5197 * If it is not set, frame->nb_samples must be equal to
5198 * avctx->frame_size for all frames except the last.
5199 * The final frame may be smaller than avctx->frame_size.
5200 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5201 * output packet is non-empty, and to 0 if it is
5202 * empty. If the function returns an error, the
5203 * packet can be assumed to be invalid, and the
5204 * value of got_packet_ptr is undefined and should
5206 * @return 0 on success, negative error code on failure
5208 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5210 attribute_deprecated
5211 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5212 const AVFrame *frame, int *got_packet_ptr);
5215 * Encode a frame of video.
5217 * Takes input raw video data from frame and writes the next output packet, if
5218 * available, to avpkt. The output packet does not necessarily contain data for
5219 * the most recent frame, as encoders can delay and reorder input frames
5220 * internally as needed.
5222 * @param avctx codec context
5223 * @param avpkt output AVPacket.
5224 * The user can supply an output buffer by setting
5225 * avpkt->data and avpkt->size prior to calling the
5226 * function, but if the size of the user-provided data is not
5227 * large enough, encoding will fail. All other AVPacket fields
5228 * will be reset by the encoder using av_init_packet(). If
5229 * avpkt->data is NULL, the encoder will allocate it.
5230 * The encoder will set avpkt->size to the size of the
5231 * output packet. The returned data (if any) belongs to the
5232 * caller, he is responsible for freeing it.
5234 * If this function fails or produces no output, avpkt will be
5235 * freed using av_packet_unref().
5236 * @param[in] frame AVFrame containing the raw video data to be encoded.
5237 * May be NULL when flushing an encoder that has the
5238 * AV_CODEC_CAP_DELAY capability set.
5239 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5240 * output packet is non-empty, and to 0 if it is
5241 * empty. If the function returns an error, the
5242 * packet can be assumed to be invalid, and the
5243 * value of got_packet_ptr is undefined and should
5245 * @return 0 on success, negative error code on failure
5247 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5249 attribute_deprecated
5250 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
5251 const AVFrame *frame, int *got_packet_ptr);
5253 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
5254 const AVSubtitle *sub);
5261 #if FF_API_AVPICTURE
5263 * @addtogroup lavc_picture
5268 * @deprecated unused
5270 attribute_deprecated
5271 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
5274 * @deprecated unused
5276 attribute_deprecated
5277 void avpicture_free(AVPicture *picture);
5280 * @deprecated use av_image_fill_arrays() instead.
5282 attribute_deprecated
5283 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
5284 enum AVPixelFormat pix_fmt, int width, int height);
5287 * @deprecated use av_image_copy_to_buffer() instead.
5289 attribute_deprecated
5290 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
5291 int width, int height,
5292 unsigned char *dest, int dest_size);
5295 * @deprecated use av_image_get_buffer_size() instead.
5297 attribute_deprecated
5298 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
5301 * @deprecated av_image_copy() instead.
5303 attribute_deprecated
5304 void av_picture_copy(AVPicture *dst, const AVPicture *src,
5305 enum AVPixelFormat pix_fmt, int width, int height);
5308 * @deprecated unused
5310 attribute_deprecated
5311 int av_picture_crop(AVPicture *dst, const AVPicture *src,
5312 enum AVPixelFormat pix_fmt, int top_band, int left_band);
5315 * @deprecated unused
5317 attribute_deprecated
5318 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
5319 int padtop, int padbottom, int padleft, int padright, int *color);
5327 * @defgroup lavc_misc Utility functions
5330 * Miscellaneous utility functions related to both encoding and decoding
5336 * @defgroup lavc_misc_pixfmt Pixel formats
5338 * Functions for working with pixel formats.
5342 #if FF_API_GETCHROMA
5344 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
5347 attribute_deprecated
5348 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
5352 * Return a value representing the fourCC code associated to the
5353 * pixel format pix_fmt, or 0 if no associated fourCC code can be
5356 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
5359 * @deprecated see av_get_pix_fmt_loss()
5361 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
5365 * Find the best pixel format to convert to given a certain source pixel
5366 * format. When converting from one pixel format to another, information loss
5367 * may occur. For example, when converting from RGB24 to GRAY, the color
5368 * information will be lost. Similarly, other losses occur when converting from
5369 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
5370 * the given pixel formats should be used to suffer the least amount of loss.
5371 * The pixel formats from which it chooses one, are determined by the
5372 * pix_fmt_list parameter.
5375 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
5376 * @param[in] src_pix_fmt source pixel format
5377 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
5378 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
5379 * @return The best pixel format to convert to or -1 if none was found.
5381 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
5382 enum AVPixelFormat src_pix_fmt,
5383 int has_alpha, int *loss_ptr);
5386 * @deprecated see av_find_best_pix_fmt_of_2()
5388 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
5389 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
5391 attribute_deprecated
5392 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
5393 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
5395 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
5401 #if FF_API_TAG_STRING
5403 * Put a string representing the codec tag codec_tag in buf.
5405 * @param buf buffer to place codec tag in
5406 * @param buf_size size in bytes of buf
5407 * @param codec_tag codec tag to assign
5408 * @return the length of the string that would have been generated if
5409 * enough space had been available, excluding the trailing null
5411 * @deprecated see av_fourcc_make_string() and av_fourcc2str().
5413 attribute_deprecated
5414 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
5417 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
5420 * Return a name for the specified profile, if available.
5422 * @param codec the codec that is searched for the given profile
5423 * @param profile the profile value for which a name is requested
5424 * @return A name for the profile if found, NULL otherwise.
5426 const char *av_get_profile_name(const AVCodec *codec, int profile);
5429 * Return a name for the specified profile, if available.
5431 * @param codec_id the ID of the codec to which the requested profile belongs
5432 * @param profile the profile value for which a name is requested
5433 * @return A name for the profile if found, NULL otherwise.
5435 * @note unlike av_get_profile_name(), which searches a list of profiles
5436 * supported by a specific decoder or encoder implementation, this
5437 * function searches the list of profiles from the AVCodecDescriptor
5439 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
5441 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
5442 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
5443 //FIXME func typedef
5446 * Fill AVFrame audio data and linesize pointers.
5448 * The buffer buf must be a preallocated buffer with a size big enough
5449 * to contain the specified samples amount. The filled AVFrame data
5450 * pointers will point to this buffer.
5452 * AVFrame extended_data channel pointers are allocated if necessary for
5455 * @param frame the AVFrame
5456 * frame->nb_samples must be set prior to calling the
5457 * function. This function fills in frame->data,
5458 * frame->extended_data, frame->linesize[0].
5459 * @param nb_channels channel count
5460 * @param sample_fmt sample format
5461 * @param buf buffer to use for frame data
5462 * @param buf_size size of buffer
5463 * @param align plane size sample alignment (0 = default)
5464 * @return >=0 on success, negative error code on failure
5465 * @todo return the size in bytes required to store the samples in
5466 * case of success, at the next libavutil bump
5468 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
5469 enum AVSampleFormat sample_fmt, const uint8_t *buf,
5470 int buf_size, int align);
5473 * Reset the internal decoder state / flush internal buffers. Should be called
5474 * e.g. when seeking or when switching to a different stream.
5476 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
5477 * this invalidates the frames previously returned from the decoder. When
5478 * refcounted frames are used, the decoder just releases any references it might
5479 * keep internally, but the caller's reference remains valid.
5481 void avcodec_flush_buffers(AVCodecContext *avctx);
5484 * Return codec bits per sample.
5486 * @param[in] codec_id the codec
5487 * @return Number of bits per sample or zero if unknown for the given codec.
5489 int av_get_bits_per_sample(enum AVCodecID codec_id);
5492 * Return the PCM codec associated with a sample format.
5493 * @param be endianness, 0 for little, 1 for big,
5494 * -1 (or anything else) for native
5495 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
5497 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
5500 * Return codec bits per sample.
5501 * Only return non-zero if the bits per sample is exactly correct, not an
5504 * @param[in] codec_id the codec
5505 * @return Number of bits per sample or zero if unknown for the given codec.
5507 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
5510 * Return audio frame duration.
5512 * @param avctx codec context
5513 * @param frame_bytes size of the frame, or 0 if unknown
5514 * @return frame duration, in samples, if known. 0 if not able to
5517 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
5520 * This function is the same as av_get_audio_frame_duration(), except it works
5521 * with AVCodecParameters instead of an AVCodecContext.
5523 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
5526 typedef struct AVBitStreamFilterContext {
5528 const struct AVBitStreamFilter *filter;
5529 AVCodecParserContext *parser;
5530 struct AVBitStreamFilterContext *next;
5532 * Internal default arguments, used if NULL is passed to av_bitstream_filter_filter().
5533 * Not for access by library users.
5536 } AVBitStreamFilterContext;
5539 typedef struct AVBSFInternal AVBSFInternal;
5542 * The bitstream filter state.
5544 * This struct must be allocated with av_bsf_alloc() and freed with
5547 * The fields in the struct will only be changed (by the caller or by the
5548 * filter) as described in their documentation, and are to be considered
5549 * immutable otherwise.
5551 typedef struct AVBSFContext {
5553 * A class for logging and AVOptions
5555 const AVClass *av_class;
5558 * The bitstream filter this context is an instance of.
5560 const struct AVBitStreamFilter *filter;
5563 * Opaque libavcodec internal data. Must not be touched by the caller in any
5566 AVBSFInternal *internal;
5569 * Opaque filter-specific private data. If filter->priv_class is non-NULL,
5570 * this is an AVOptions-enabled struct.
5575 * Parameters of the input stream. This field is allocated in
5576 * av_bsf_alloc(), it needs to be filled by the caller before
5579 AVCodecParameters *par_in;
5582 * Parameters of the output stream. This field is allocated in
5583 * av_bsf_alloc(), it is set by the filter in av_bsf_init().
5585 AVCodecParameters *par_out;
5588 * The timebase used for the timestamps of the input packets. Set by the
5589 * caller before av_bsf_init().
5591 AVRational time_base_in;
5594 * The timebase used for the timestamps of the output packets. Set by the
5595 * filter in av_bsf_init().
5597 AVRational time_base_out;
5600 typedef struct AVBitStreamFilter {
5604 * A list of codec ids supported by the filter, terminated by
5606 * May be NULL, in that case the bitstream filter works with any codec id.
5608 const enum AVCodecID *codec_ids;
5611 * A class for the private data, used to declare bitstream filter private
5612 * AVOptions. This field is NULL for bitstream filters that do not declare
5615 * If this field is non-NULL, the first member of the filter private data
5616 * must be a pointer to AVClass, which will be set by libavcodec generic
5617 * code to this class.
5619 const AVClass *priv_class;
5621 /*****************************************************************
5622 * No fields below this line are part of the public API. They
5623 * may not be used outside of libavcodec and can be changed and
5625 * New public fields should be added right above.
5626 *****************************************************************
5630 int (*init)(AVBSFContext *ctx);
5631 int (*filter)(AVBSFContext *ctx, AVPacket *pkt);
5632 void (*close)(AVBSFContext *ctx);
5633 } AVBitStreamFilter;
5637 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5638 * is deprecated. Use the new bitstream filtering API (using AVBSFContext).
5640 attribute_deprecated
5641 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
5643 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5644 * is deprecated. Use av_bsf_get_by_name(), av_bsf_alloc(), and av_bsf_init()
5645 * from the new bitstream filtering API (using AVBSFContext).
5647 attribute_deprecated
5648 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
5650 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5651 * is deprecated. Use av_bsf_send_packet() and av_bsf_receive_packet() from the
5652 * new bitstream filtering API (using AVBSFContext).
5654 attribute_deprecated
5655 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
5656 AVCodecContext *avctx, const char *args,
5657 uint8_t **poutbuf, int *poutbuf_size,
5658 const uint8_t *buf, int buf_size, int keyframe);
5660 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5661 * is deprecated. Use av_bsf_free() from the new bitstream filtering API (using
5664 attribute_deprecated
5665 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
5667 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
5668 * is deprecated. Use av_bsf_next() from the new bitstream filtering API (using
5671 attribute_deprecated
5672 const AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
5676 * @return a bitstream filter with the specified name or NULL if no such
5677 * bitstream filter exists.
5679 const AVBitStreamFilter *av_bsf_get_by_name(const char *name);
5682 * Iterate over all registered bitstream filters.
5684 * @param opaque a pointer where libavcodec will store the iteration state. Must
5685 * point to NULL to start the iteration.
5687 * @return the next registered bitstream filter or NULL when the iteration is
5690 const AVBitStreamFilter *av_bsf_next(void **opaque);
5693 * Allocate a context for a given bitstream filter. The caller must fill in the
5694 * context parameters as described in the documentation and then call
5695 * av_bsf_init() before sending any data to the filter.
5697 * @param filter the filter for which to allocate an instance.
5698 * @param ctx a pointer into which the pointer to the newly-allocated context
5699 * will be written. It must be freed with av_bsf_free() after the
5700 * filtering is done.
5702 * @return 0 on success, a negative AVERROR code on failure
5704 int av_bsf_alloc(const AVBitStreamFilter *filter, AVBSFContext **ctx);
5707 * Prepare the filter for use, after all the parameters and options have been
5710 int av_bsf_init(AVBSFContext *ctx);
5713 * Submit a packet for filtering.
5715 * After sending each packet, the filter must be completely drained by calling
5716 * av_bsf_receive_packet() repeatedly until it returns AVERROR(EAGAIN) or
5719 * @param pkt the packet to filter. The bitstream filter will take ownership of
5720 * the packet and reset the contents of pkt. pkt is not touched if an error occurs.
5721 * This parameter may be NULL, which signals the end of the stream (i.e. no more
5722 * packets will be sent). That will cause the filter to output any packets it
5723 * may have buffered internally.
5725 * @return 0 on success, a negative AVERROR on error.
5727 int av_bsf_send_packet(AVBSFContext *ctx, AVPacket *pkt);
5730 * Retrieve a filtered packet.
5732 * @param[out] pkt this struct will be filled with the contents of the filtered
5733 * packet. It is owned by the caller and must be freed using
5734 * av_packet_unref() when it is no longer needed.
5735 * This parameter should be "clean" (i.e. freshly allocated
5736 * with av_packet_alloc() or unreffed with av_packet_unref())
5737 * when this function is called. If this function returns
5738 * successfully, the contents of pkt will be completely
5739 * overwritten by the returned data. On failure, pkt is not
5742 * @return 0 on success. AVERROR(EAGAIN) if more packets need to be sent to the
5743 * filter (using av_bsf_send_packet()) to get more output. AVERROR_EOF if there
5744 * will be no further output from the filter. Another negative AVERROR value if
5747 * @note one input packet may result in several output packets, so after sending
5748 * a packet with av_bsf_send_packet(), this function needs to be called
5749 * repeatedly until it stops returning 0. It is also possible for a filter to
5750 * output fewer packets than were sent to it, so this function may return
5751 * AVERROR(EAGAIN) immediately after a successful av_bsf_send_packet() call.
5753 int av_bsf_receive_packet(AVBSFContext *ctx, AVPacket *pkt);
5756 * Free a bitstream filter context and everything associated with it; write NULL
5757 * into the supplied pointer.
5759 void av_bsf_free(AVBSFContext **ctx);
5762 * Get the AVClass for AVBSFContext. It can be used in combination with
5763 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
5765 * @see av_opt_find().
5767 const AVClass *av_bsf_get_class(void);
5770 * Structure for chain/list of bitstream filters.
5771 * Empty list can be allocated by av_bsf_list_alloc().
5773 typedef struct AVBSFList AVBSFList;
5776 * Allocate empty list of bitstream filters.
5777 * The list must be later freed by av_bsf_list_free()
5778 * or finalized by av_bsf_list_finalize().
5780 * @return Pointer to @ref AVBSFList on success, NULL in case of failure
5782 AVBSFList *av_bsf_list_alloc(void);
5785 * Free list of bitstream filters.
5787 * @param lst Pointer to pointer returned by av_bsf_list_alloc()
5789 void av_bsf_list_free(AVBSFList **lst);
5792 * Append bitstream filter to the list of bitstream filters.
5794 * @param lst List to append to
5795 * @param bsf Filter context to be appended
5797 * @return >=0 on success, negative AVERROR in case of failure
5799 int av_bsf_list_append(AVBSFList *lst, AVBSFContext *bsf);
5802 * Construct new bitstream filter context given it's name and options
5803 * and append it to the list of bitstream filters.
5805 * @param lst List to append to
5806 * @param bsf_name Name of the bitstream filter
5807 * @param options Options for the bitstream filter, can be set to NULL
5809 * @return >=0 on success, negative AVERROR in case of failure
5811 int av_bsf_list_append2(AVBSFList *lst, const char * bsf_name, AVDictionary **options);
5813 * Finalize list of bitstream filters.
5815 * This function will transform @ref AVBSFList to single @ref AVBSFContext,
5816 * so the whole chain of bitstream filters can be treated as single filter
5817 * freshly allocated by av_bsf_alloc().
5818 * If the call is successful, @ref AVBSFList structure is freed and lst
5819 * will be set to NULL. In case of failure, caller is responsible for
5820 * freeing the structure by av_bsf_list_free()
5822 * @param lst Filter list structure to be transformed
5823 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
5824 * representing the chain of bitstream filters
5826 * @return >=0 on success, negative AVERROR in case of failure
5828 int av_bsf_list_finalize(AVBSFList **lst, AVBSFContext **bsf);
5831 * Parse string describing list of bitstream filters and create single
5832 * @ref AVBSFContext describing the whole chain of bitstream filters.
5833 * Resulting @ref AVBSFContext can be treated as any other @ref AVBSFContext freshly
5834 * allocated by av_bsf_alloc().
5836 * @param str String describing chain of bitstream filters in format
5837 * `bsf1[=opt1=val1:opt2=val2][,bsf2]`
5838 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
5839 * representing the chain of bitstream filters
5841 * @return >=0 on success, negative AVERROR in case of failure
5843 int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf);
5846 * Get null/pass-through bitstream filter.
5848 * @param[out] bsf Pointer to be set to new instance of pass-through bitstream filter
5852 int av_bsf_get_null_filter(AVBSFContext **bsf);
5857 * Same behaviour av_fast_malloc but the buffer has additional
5858 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
5860 * In addition the whole buffer will initially and after resizes
5861 * be 0-initialized so that no uninitialized data will ever appear.
5863 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
5866 * Same behaviour av_fast_padded_malloc except that buffer will always
5867 * be 0-initialized after call.
5869 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
5872 * Encode extradata length to a buffer. Used by xiph codecs.
5874 * @param s buffer to write to; must be at least (v/255+1) bytes long
5875 * @param v size of extradata in bytes
5876 * @return number of bytes written to the buffer.
5878 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
5880 #if FF_API_USER_VISIBLE_AVHWACCEL
5882 * Register the hardware accelerator hwaccel.
5884 * @deprecated This function doesn't do anything.
5886 attribute_deprecated
5887 void av_register_hwaccel(AVHWAccel *hwaccel);
5890 * If hwaccel is NULL, returns the first registered hardware accelerator,
5891 * if hwaccel is non-NULL, returns the next registered hardware accelerator
5892 * after hwaccel, or NULL if hwaccel is the last one.
5894 * @deprecated AVHWaccel structures contain no user-serviceable parts, so
5895 * this function should not be used.
5897 attribute_deprecated
5898 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
5903 * Lock operation used by lockmgr
5906 AV_LOCK_CREATE, ///< Create a mutex
5907 AV_LOCK_OBTAIN, ///< Lock the mutex
5908 AV_LOCK_RELEASE, ///< Unlock the mutex
5909 AV_LOCK_DESTROY, ///< Free mutex resources
5913 * Register a user provided lock manager supporting the operations
5914 * specified by AVLockOp. The "mutex" argument to the function points
5915 * to a (void *) where the lockmgr should store/get a pointer to a user
5916 * allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
5917 * value left by the last call for all other ops. If the lock manager is
5918 * unable to perform the op then it should leave the mutex in the same
5919 * state as when it was called and return a non-zero value. However,
5920 * when called with AV_LOCK_DESTROY the mutex will always be assumed to
5921 * have been successfully destroyed. If av_lockmgr_register succeeds
5922 * it will return a non-negative value, if it fails it will return a
5923 * negative value and destroy all mutex and unregister all callbacks.
5924 * av_lockmgr_register is not thread-safe, it must be called from a
5925 * single thread before any calls which make use of locking are used.
5927 * @param cb User defined callback. av_lockmgr_register invokes calls
5928 * to this callback and the previously registered callback.
5929 * The callback will be used to create more than one mutex
5930 * each of which must be backed by its own underlying locking
5931 * mechanism (i.e. do not use a single static object to
5932 * implement your lock manager). If cb is set to NULL the
5933 * lockmgr will be unregistered.
5935 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
5938 * Get the type of the given codec.
5940 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
5943 * Get the name of a codec.
5944 * @return a static string identifying the codec; never NULL
5946 const char *avcodec_get_name(enum AVCodecID id);
5949 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
5950 * with no corresponding avcodec_close()), 0 otherwise.
5952 int avcodec_is_open(AVCodecContext *s);
5955 * @return a non-zero number if codec is an encoder, zero otherwise
5957 int av_codec_is_encoder(const AVCodec *codec);
5960 * @return a non-zero number if codec is a decoder, zero otherwise
5962 int av_codec_is_decoder(const AVCodec *codec);
5965 * @return descriptor for given codec ID or NULL if no descriptor exists.
5967 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
5970 * Iterate over all codec descriptors known to libavcodec.
5972 * @param prev previous descriptor. NULL to get the first descriptor.
5974 * @return next descriptor or NULL after the last descriptor
5976 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
5979 * @return codec descriptor with the given name or NULL if no such descriptor
5982 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
5985 * Allocate a CPB properties structure and initialize its fields to default
5988 * @param size if non-NULL, the size of the allocated struct will be written
5989 * here. This is useful for embedding it in side data.
5991 * @return the newly allocated struct or NULL on failure
5993 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
5999 #endif /* AVCODEC_AVCODEC_H */