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avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
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.
10  *
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.
15  *
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
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include <errno.h>
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
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"
43 
44 #include "version.h"
45 
46 /**
47  * @defgroup libavc libavcodec
48  * Encoding/Decoding Library
49  *
50  * @{
51  *
52  * @defgroup lavc_decoding Decoding
53  * @{
54  * @}
55  *
56  * @defgroup lavc_encoding Encoding
57  * @{
58  * @}
59  *
60  * @defgroup lavc_codec Codecs
61  * @{
62  * @defgroup lavc_codec_native Native Codecs
63  * @{
64  * @}
65  * @defgroup lavc_codec_wrappers External library wrappers
66  * @{
67  * @}
68  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
69  * @{
70  * @}
71  * @}
72  * @defgroup lavc_internal Internal
73  * @{
74  * @}
75  * @}
76  */
77 
78 /**
79  * @ingroup libavc
80  * @defgroup lavc_encdec send/receive encoding and decoding API overview
81  * @{
82  *
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.
86  *
87  * The API is very similar for encoding/decoding and audio/video, and works as
88  * follows:
89  * - Set up and open the AVCodecContext as usual.
90  * - Send valid input:
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.
110  *
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
114  * outlined above.
115  *
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
120  * returns EAGAIN.
121  *
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
128  * mode.
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().
134  *
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.
143  *
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.
149  *
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
164  * possible.
165  * - The new API does not handle subtitles yet.
166  *
167  * Mixing new and old function calls on the same AVCodecContext is not allowed,
168  * and will result in undefined behavior.
169  *
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.
172  *
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.
187  * @}
188  */
189 
190 /**
191  * @defgroup lavc_core Core functions/structures.
192  * @ingroup libavc
193  *
194  * Basic definitions, functions for querying libavcodec capabilities,
195  * allocating core structures, etc.
196  * @{
197  */
198 
199 
200 /**
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
206  * details.
207  *
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
211  *
212  * After adding new codec IDs, do not forget to add an entry to the codec
213  * descriptor list and bump libavcodec minor version.
214  */
215 enum AVCodecID {
217 
218  /* video codecs */
220  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
355 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
393 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
412 
449 
450  /* various PCM "codecs" */
451  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
483 
488 
489  /* various ADPCM codecs */
521 
532 
533  /* AMR */
536 
537  /* RealAudio codecs*/
540 
541  /* various DPCM codecs */
546 
549 
550  /* audio codecs */
551  AV_CODEC_ID_MP2 = 0x15000,
552  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
569  AV_CODEC_ID_GSM, ///< as in Berlin toast format
581  AV_CODEC_ID_GSM_MS, /* as found in WAV */
618 
637 
638  /* subtitle codecs */
639  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
642  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
649 
665 
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,
669 
670  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
679 
680 
681  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
682 
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
689 };
690 
691 /**
692  * This struct describes the properties of a single codec described by an
693  * AVCodecID.
694  * @see avcodec_descriptor_get()
695  */
696 typedef struct AVCodecDescriptor {
697  enum AVCodecID id;
699  /**
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.
703  */
704  const char *name;
705  /**
706  * A more descriptive name for this codec. May be NULL.
707  */
708  const char *long_name;
709  /**
710  * Codec properties, a combination of AV_CODEC_PROP_* flags.
711  */
712  int props;
713  /**
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.
717  */
718  const char *const *mime_types;
719  /**
720  * If non-NULL, an array of profiles recognized for this codec.
721  * Terminated with FF_PROFILE_UNKNOWN.
722  */
723  const struct AVProfile *profiles;
725 
726 /**
727  * Codec uses only intra compression.
728  * Video and audio codecs only.
729  */
730 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
731 /**
732  * Codec supports lossy compression. Audio and video codecs only.
733  * @note a codec may support both lossy and lossless
734  * compression modes
735  */
736 #define AV_CODEC_PROP_LOSSY (1 << 1)
737 /**
738  * Codec supports lossless compression. Audio and video codecs only.
739  */
740 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
741 /**
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
745  * frames.
746  *
747  * For codecs that do not have this property set, PTS and DTS should always be
748  * equal.
749  */
750 #define AV_CODEC_PROP_REORDER (1 << 3)
751 /**
752  * Subtitle codec is bitmap based
753  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
754  */
755 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
756 /**
757  * Subtitle codec is text based.
758  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
759  */
760 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
761 
762 /**
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.
769  */
770 #define AV_INPUT_BUFFER_PADDING_SIZE 32
771 
772 /**
773  * @ingroup lavc_encoding
774  * minimum encoding buffer size
775  * Used to avoid some checks during header writing.
776  */
777 #define AV_INPUT_BUFFER_MIN_SIZE 16384
778 
779 /**
780  * @ingroup lavc_decoding
781  */
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
792 };
793 
804  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
805 };
806 
807 /**
808  * @ingroup lavc_encoding
809  */
810 typedef struct RcOverride{
813  int qscale; // If this is 0 then quality_factor will be used instead.
815 } RcOverride;
816 
817 /* encoding support
818  These flags can be passed in AVCodecContext.flags before initialization.
819  Note: Not everything is supported yet.
820 */
821 
822 /**
823  * Allow decoders to produce frames with data planes that are not aligned
824  * to CPU requirements (e.g. due to cropping).
825  */
826 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
827 /**
828  * Use fixed qscale.
829  */
830 #define AV_CODEC_FLAG_QSCALE (1 << 1)
831 /**
832  * 4 MV per MB allowed / advanced prediction for H.263.
833  */
834 #define AV_CODEC_FLAG_4MV (1 << 2)
835 /**
836  * Output even those frames that might be corrupted.
837  */
838 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
839 /**
840  * Use qpel MC.
841  */
842 #define AV_CODEC_FLAG_QPEL (1 << 4)
843 /**
844  * Use internal 2pass ratecontrol in first pass mode.
845  */
846 #define AV_CODEC_FLAG_PASS1 (1 << 9)
847 /**
848  * Use internal 2pass ratecontrol in second pass mode.
849  */
850 #define AV_CODEC_FLAG_PASS2 (1 << 10)
851 /**
852  * loop filter.
853  */
854 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
855 /**
856  * Only decode/encode grayscale.
857  */
858 #define AV_CODEC_FLAG_GRAY (1 << 13)
859 /**
860  * error[?] variables will be set during encoding.
861  */
862 #define AV_CODEC_FLAG_PSNR (1 << 15)
863 /**
864  * Input bitstream might be truncated at a random location
865  * instead of only at frame boundaries.
866  */
867 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
868 /**
869  * Use interlaced DCT.
870  */
871 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
872 /**
873  * Force low delay.
874  */
875 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
876 /**
877  * Place global headers in extradata instead of every keyframe.
878  */
879 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
880 /**
881  * Use only bitexact stuff (except (I)DCT).
882  */
883 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
884 /* Fx : Flag for H.263+ extra options */
885 /**
886  * H.263 advanced intra coding / MPEG-4 AC prediction
887  */
888 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
889 /**
890  * interlaced motion estimation
891  */
892 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
893 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
894 
895 /**
896  * Allow non spec compliant speedup tricks.
897  */
898 #define AV_CODEC_FLAG2_FAST (1 << 0)
899 /**
900  * Skip bitstream encoding.
901  */
902 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
903 /**
904  * Place global headers at every keyframe instead of in extradata.
905  */
906 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
907 
908 /**
909  * timecode is in drop frame format. DEPRECATED!!!!
910  */
911 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
912 
913 /**
914  * Input bitstream might be truncated at a packet boundaries
915  * instead of only at frame boundaries.
916  */
917 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
918 /**
919  * Discard cropping information from SPS.
920  */
921 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
922 
923 /**
924  * Show all frames before the first keyframe
925  */
926 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
927 /**
928  * Export motion vectors through frame side data
929  */
930 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
931 /**
932  * Do not skip samples and export skip information as frame side data
933  */
934 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
935 /**
936  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
937  */
938 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
939 
940 /* Unsupported options :
941  * Syntax Arithmetic coding (SAC)
942  * Reference Picture Selection
943  * Independent Segment Decoding */
944 /* /Fx */
945 /* codec capabilities */
946 
947 /**
948  * Decoder can use draw_horiz_band callback.
949  */
950 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
951 /**
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.
955  */
956 #define AV_CODEC_CAP_DR1 (1 << 1)
957 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
958 /**
959  * Encoder or decoder requires flushing with NULL input at the end in order to
960  * give the complete and correct output.
961  *
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.
966  *
967  * Decoders:
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
970  * returns frames.
971  *
972  * Encoders:
973  * The encoder needs to be fed with NULL data at the end of encoding until the
974  * encoder no longer returns data.
975  *
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.
980  */
981 #define AV_CODEC_CAP_DELAY (1 << 5)
982 /**
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.
985  */
986 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
987 
988 /**
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
997  * as a last resort.
998  */
999 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1000 /**
1001  * Codec is experimental and is thus avoided in favor of non experimental
1002  * encoders
1003  */
1004 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1005 /**
1006  * Codec should fill in channel configuration and samplerate instead of container
1007  */
1008 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1009 /**
1010  * Codec supports frame-level multithreading.
1011  */
1012 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1013 /**
1014  * Codec supports slice-based (or partition-based) multithreading.
1015  */
1016 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1017 /**
1018  * Codec supports changed parameters at any point.
1019  */
1020 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1021 /**
1022  * Codec supports avctx->thread_count == 0 (auto).
1023  */
1024 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1025 /**
1026  * Audio encoder supports receiving a different number of samples in each call.
1027  */
1028 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1029 /**
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
1034  * the stream.
1035  * A decoder marked with this flag should only be used as last resort
1036  * choice for probing.
1037  */
1038 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1039 /**
1040  * Codec is intra only.
1041  */
1042 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1043 /**
1044  * Codec is lossless.
1045  */
1046 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1047 
1048 /**
1049  * Codec is backed by a hardware implementation. Typically used to
1050  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1051  * avcodec_get_hw_config() instead.
1052  */
1053 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1054 
1055 /**
1056  * Codec is potentially backed by a hardware implementation, but not
1057  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1058  * implementation provides some sort of internal fallback.
1059  */
1060 #define AV_CODEC_CAP_HYBRID (1 << 19)
1061 
1062 /**
1063  * Pan Scan area.
1064  * This specifies the area which should be displayed.
1065  * Note there may be multiple such areas for one frame.
1066  */
1067 typedef struct AVPanScan {
1068  /**
1069  * id
1070  * - encoding: Set by user.
1071  * - decoding: Set by libavcodec.
1072  */
1073  int id;
1074 
1075  /**
1076  * width and height in 1/16 pel
1077  * - encoding: Set by user.
1078  * - decoding: Set by libavcodec.
1079  */
1080  int width;
1081  int height;
1082 
1083  /**
1084  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1085  * - encoding: Set by user.
1086  * - decoding: Set by libavcodec.
1087  */
1088  int16_t position[3][2];
1089 } AVPanScan;
1090 
1091 /**
1092  * This structure describes the bitrate properties of an encoded bitstream. It
1093  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1094  * parameters for H.264/HEVC.
1095  */
1096 typedef struct AVCPBProperties {
1097  /**
1098  * Maximum bitrate of the stream, in bits per second.
1099  * Zero if unknown or unspecified.
1100  */
1102  /**
1103  * Minimum bitrate of the stream, in bits per second.
1104  * Zero if unknown or unspecified.
1105  */
1107  /**
1108  * Average bitrate of the stream, in bits per second.
1109  * Zero if unknown or unspecified.
1110  */
1112 
1113  /**
1114  * The size of the buffer to which the ratecontrol is applied, in bits.
1115  * Zero if unknown or unspecified.
1116  */
1118 
1119  /**
1120  * The delay between the time the packet this structure is associated with
1121  * is received and the time when it should be decoded, in periods of a 27MHz
1122  * clock.
1123  *
1124  * UINT64_MAX when unknown or unspecified.
1125  */
1126  uint64_t vbv_delay;
1127 } AVCPBProperties;
1128 
1129 /**
1130  * The decoder will keep a reference to the frame and may reuse it later.
1131  */
1132 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1133 
1134 /**
1135  * @defgroup lavc_packet AVPacket
1136  *
1137  * Types and functions for working with AVPacket.
1138  * @{
1139  */
1141  /**
1142  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1143  * bytes worth of palette. This side data signals that a new palette is
1144  * present.
1145  */
1147 
1148  /**
1149  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1150  * that the extradata buffer was changed and the receiving side should
1151  * act upon it appropriately. The new extradata is embedded in the side
1152  * data buffer and should be immediately used for processing the current
1153  * frame or packet.
1154  */
1156 
1157  /**
1158  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1159  * @code
1160  * u32le param_flags
1161  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1162  * s32le channel_count
1163  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1164  * u64le channel_layout
1165  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1166  * s32le sample_rate
1167  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1168  * s32le width
1169  * s32le height
1170  * @endcode
1171  */
1173 
1174  /**
1175  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1176  * structures with info about macroblocks relevant to splitting the
1177  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1178  * That is, it does not necessarily contain info about all macroblocks,
1179  * as long as the distance between macroblocks in the info is smaller
1180  * than the target payload size.
1181  * Each MB info structure is 12 bytes, and is laid out as follows:
1182  * @code
1183  * u32le bit offset from the start of the packet
1184  * u8 current quantizer at the start of the macroblock
1185  * u8 GOB number
1186  * u16le macroblock address within the GOB
1187  * u8 horizontal MV predictor
1188  * u8 vertical MV predictor
1189  * u8 horizontal MV predictor for block number 3
1190  * u8 vertical MV predictor for block number 3
1191  * @endcode
1192  */
1194 
1195  /**
1196  * This side data should be associated with an audio stream and contains
1197  * ReplayGain information in form of the AVReplayGain struct.
1198  */
1200 
1201  /**
1202  * This side data contains a 3x3 transformation matrix describing an affine
1203  * transformation that needs to be applied to the decoded video frames for
1204  * correct presentation.
1205  *
1206  * See libavutil/display.h for a detailed description of the data.
1207  */
1209 
1210  /**
1211  * This side data should be associated with a video stream and contains
1212  * Stereoscopic 3D information in form of the AVStereo3D struct.
1213  */
1215 
1216  /**
1217  * This side data should be associated with an audio stream and corresponds
1218  * to enum AVAudioServiceType.
1219  */
1221 
1222  /**
1223  * This side data contains quality related information from the encoder.
1224  * @code
1225  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1226  * u8 picture type
1227  * u8 error count
1228  * u16 reserved
1229  * u64le[error count] sum of squared differences between encoder in and output
1230  * @endcode
1231  */
1233 
1234  /**
1235  * This side data contains an integer value representing the stream index
1236  * of a "fallback" track. A fallback track indicates an alternate
1237  * track to use when the current track can not be decoded for some reason.
1238  * e.g. no decoder available for codec.
1239  */
1241 
1242  /**
1243  * This side data corresponds to the AVCPBProperties struct.
1244  */
1246 
1247  /**
1248  * Recommmends skipping the specified number of samples
1249  * @code
1250  * u32le number of samples to skip from start of this packet
1251  * u32le number of samples to skip from end of this packet
1252  * u8 reason for start skip
1253  * u8 reason for end skip (0=padding silence, 1=convergence)
1254  * @endcode
1255  */
1257 
1258  /**
1259  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1260  * the packet may contain "dual mono" audio specific to Japanese DTV
1261  * and if it is true, recommends only the selected channel to be used.
1262  * @code
1263  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1264  * @endcode
1265  */
1267 
1268  /**
1269  * A list of zero terminated key/value strings. There is no end marker for
1270  * the list, so it is required to rely on the side data size to stop.
1271  */
1273 
1274  /**
1275  * Subtitle event position
1276  * @code
1277  * u32le x1
1278  * u32le y1
1279  * u32le x2
1280  * u32le y2
1281  * @endcode
1282  */
1284 
1285  /**
1286  * Data found in BlockAdditional element of matroska container. There is
1287  * no end marker for the data, so it is required to rely on the side data
1288  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1289  * by data.
1290  */
1292 
1293  /**
1294  * The optional first identifier line of a WebVTT cue.
1295  */
1297 
1298  /**
1299  * The optional settings (rendering instructions) that immediately
1300  * follow the timestamp specifier of a WebVTT cue.
1301  */
1303 
1304  /**
1305  * A list of zero terminated key/value strings. There is no end marker for
1306  * the list, so it is required to rely on the side data size to stop. This
1307  * side data includes updated metadata which appeared in the stream.
1308  */
1310 
1311  /**
1312  * MPEGTS stream ID, this is required to pass the stream ID
1313  * information from the demuxer to the corresponding muxer.
1314  */
1316 
1317  /**
1318  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1319  * should be associated with a video stream and contains data in the form
1320  * of the AVMasteringDisplayMetadata struct.
1321  */
1323 
1324  /**
1325  * This side data should be associated with a video stream and corresponds
1326  * to the AVSphericalMapping structure.
1327  */
1329 
1330  /**
1331  * Content light level (based on CTA-861.3). This metadata should be
1332  * associated with a video stream and contains data in the form of the
1333  * AVContentLightMetadata struct.
1334  */
1336 
1337  /**
1338  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1339  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1340  * The number of bytes of CC data is AVPacketSideData.size.
1341  */
1343 
1344  /**
1345  * The number of side data types.
1346  * This is not part of the public API/ABI in the sense that it may
1347  * change when new side data types are added.
1348  * This must stay the last enum value.
1349  * If its value becomes huge, some code using it
1350  * needs to be updated as it assumes it to be smaller than other limits.
1351  */
1353 };
1354 
1355 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1356 
1357 typedef struct AVPacketSideData {
1359  int size;
1362 
1363 /**
1364  * This structure stores compressed data. It is typically exported by demuxers
1365  * and then passed as input to decoders, or received as output from encoders and
1366  * then passed to muxers.
1367  *
1368  * For video, it should typically contain one compressed frame. For audio it may
1369  * contain several compressed frames. Encoders are allowed to output empty
1370  * packets, with no compressed data, containing only side data
1371  * (e.g. to update some stream parameters at the end of encoding).
1372  *
1373  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1374  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1375  * without libavcodec and libavformat major bump.
1376  *
1377  * The semantics of data ownership depends on the buf field.
1378  * If it is set, the packet data is dynamically allocated and is
1379  * valid indefinitely until a call to av_packet_unref() reduces the
1380  * reference count to 0.
1381  *
1382  * If the buf field is not set av_packet_ref() would make a copy instead
1383  * of increasing the reference count.
1384  *
1385  * The side data is always allocated with av_malloc(), copied by
1386  * av_packet_ref() and freed by av_packet_unref().
1387  *
1388  * @see av_packet_ref
1389  * @see av_packet_unref
1390  */
1391 typedef struct AVPacket {
1392  /**
1393  * A reference to the reference-counted buffer where the packet data is
1394  * stored.
1395  * May be NULL, then the packet data is not reference-counted.
1396  */
1398  /**
1399  * Presentation timestamp in AVStream->time_base units; the time at which
1400  * the decompressed packet will be presented to the user.
1401  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1402  * pts MUST be larger or equal to dts as presentation cannot happen before
1403  * decompression, unless one wants to view hex dumps. Some formats misuse
1404  * the terms dts and pts/cts to mean something different. Such timestamps
1405  * must be converted to true pts/dts before they are stored in AVPacket.
1406  */
1407  int64_t pts;
1408  /**
1409  * Decompression timestamp in AVStream->time_base units; the time at which
1410  * the packet is decompressed.
1411  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1412  */
1413  int64_t dts;
1415  int size;
1417  /**
1418  * A combination of AV_PKT_FLAG values
1419  */
1420  int flags;
1421  /**
1422  * Additional packet data that can be provided by the container.
1423  * Packet can contain several types of side information.
1424  */
1427 
1428  /**
1429  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1430  * Equals next_pts - this_pts in presentation order.
1431  */
1432  int64_t duration;
1433 
1434  int64_t pos; ///< byte position in stream, -1 if unknown
1435 
1436 #if FF_API_CONVERGENCE_DURATION
1437  /**
1438  * @deprecated Same as the duration field, but as int64_t. This was required
1439  * for Matroska subtitles, whose duration values could overflow when the
1440  * duration field was still an int.
1441  */
1444 #endif
1445 } AVPacket;
1446 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1447 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1448 /**
1449  * Flag is used to discard packets which are required to maintain valid
1450  * decoder state but are not required for output and should be dropped
1451  * after decoding.
1452  **/
1453 #define AV_PKT_FLAG_DISCARD 0x0004
1454 /**
1455  * The packet comes from a trusted source.
1456  *
1457  * Otherwise-unsafe constructs such as arbitrary pointers to data
1458  * outside the packet may be followed.
1459  */
1460 #define AV_PKT_FLAG_TRUSTED 0x0008
1461 /**
1462  * Flag is used to indicate packets that contain frames that can
1463  * be discarded by the decoder. I.e. Non-reference frames.
1464  */
1465 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1466 
1467 
1473 };
1474 /**
1475  * @}
1476  */
1477 
1478 struct AVCodecInternal;
1479 
1483  AV_FIELD_TT, //< Top coded_first, top displayed first
1484  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1485  AV_FIELD_TB, //< Top coded first, bottom displayed first
1486  AV_FIELD_BT, //< Bottom coded first, top displayed first
1487 };
1488 
1489 /**
1490  * main external API structure.
1491  * New fields can be added to the end with minor version bumps.
1492  * Removal, reordering and changes to existing fields require a major
1493  * version bump.
1494  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1495  * applications.
1496  * The name string for AVOptions options matches the associated command line
1497  * parameter name and can be found in libavcodec/options_table.h
1498  * The AVOption/command line parameter names differ in some cases from the C
1499  * structure field names for historic reasons or brevity.
1500  * sizeof(AVCodecContext) must not be used outside libav*.
1501  */
1502 typedef struct AVCodecContext {
1503  /**
1504  * information on struct for av_log
1505  * - set by avcodec_alloc_context3
1506  */
1509 
1510  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1511  const struct AVCodec *codec;
1512  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1513 
1514  /**
1515  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1516  * This is used to work around some encoder bugs.
1517  * A demuxer should set this to what is stored in the field used to identify the codec.
1518  * If there are multiple such fields in a container then the demuxer should choose the one
1519  * which maximizes the information about the used codec.
1520  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1521  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1522  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1523  * first.
1524  * - encoding: Set by user, if not then the default based on codec_id will be used.
1525  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1526  */
1527  unsigned int codec_tag;
1528 
1529  void *priv_data;
1530 
1531  /**
1532  * Private context used for internal data.
1533  *
1534  * Unlike priv_data, this is not codec-specific. It is used in general
1535  * libavcodec functions.
1536  */
1537  struct AVCodecInternal *internal;
1538 
1539  /**
1540  * Private data of the user, can be used to carry app specific stuff.
1541  * - encoding: Set by user.
1542  * - decoding: Set by user.
1543  */
1544  void *opaque;
1545 
1546  /**
1547  * the average bitrate
1548  * - encoding: Set by user; unused for constant quantizer encoding.
1549  * - decoding: Set by user, may be overwritten by libavcodec
1550  * if this info is available in the stream
1551  */
1552  int64_t bit_rate;
1553 
1554  /**
1555  * number of bits the bitstream is allowed to diverge from the reference.
1556  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1557  * - encoding: Set by user; unused for constant quantizer encoding.
1558  * - decoding: unused
1559  */
1561 
1562  /**
1563  * Global quality for codecs which cannot change it per frame.
1564  * This should be proportional to MPEG-1/2/4 qscale.
1565  * - encoding: Set by user.
1566  * - decoding: unused
1567  */
1569 
1570  /**
1571  * - encoding: Set by user.
1572  * - decoding: unused
1573  */
1575 #define FF_COMPRESSION_DEFAULT -1
1576 
1577  /**
1578  * AV_CODEC_FLAG_*.
1579  * - encoding: Set by user.
1580  * - decoding: Set by user.
1581  */
1582  int flags;
1583 
1584  /**
1585  * AV_CODEC_FLAG2_*
1586  * - encoding: Set by user.
1587  * - decoding: Set by user.
1588  */
1589  int flags2;
1590 
1591  /**
1592  * some codecs need / can use extradata like Huffman tables.
1593  * MJPEG: Huffman tables
1594  * rv10: additional flags
1595  * MPEG-4: global headers (they can be in the bitstream or here)
1596  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1597  * than extradata_size to avoid problems if it is read with the bitstream reader.
1598  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1599  * - encoding: Set/allocated/freed by libavcodec.
1600  * - decoding: Set/allocated/freed by user.
1601  */
1604 
1605  /**
1606  * This is the fundamental unit of time (in seconds) in terms
1607  * of which frame timestamps are represented. For fixed-fps content,
1608  * timebase should be 1/framerate and timestamp increments should be
1609  * identically 1.
1610  * This often, but not always is the inverse of the frame rate or field rate
1611  * for video. 1/time_base is not the average frame rate if the frame rate is not
1612  * constant.
1613  *
1614  * Like containers, elementary streams also can store timestamps, 1/time_base
1615  * is the unit in which these timestamps are specified.
1616  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1617  * vop_time_increment_resolution and fixed_vop_rate
1618  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1619  *
1620  * - encoding: MUST be set by user.
1621  * - decoding: the use of this field for decoding is deprecated.
1622  * Use framerate instead.
1623  */
1625 
1626  /**
1627  * For some codecs, the time base is closer to the field rate than the frame rate.
1628  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1629  * if no telecine is used ...
1630  *
1631  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1632  */
1634 
1635  /**
1636  * Codec delay.
1637  *
1638  * Encoding: Number of frames delay there will be from the encoder input to
1639  * the decoder output. (we assume the decoder matches the spec)
1640  * Decoding: Number of frames delay in addition to what a standard decoder
1641  * as specified in the spec would produce.
1642  *
1643  * Video:
1644  * Number of frames the decoded output will be delayed relative to the
1645  * encoded input.
1646  *
1647  * Audio:
1648  * For encoding, this field is unused (see initial_padding).
1649  *
1650  * For decoding, this is the number of samples the decoder needs to
1651  * output before the decoder's output is valid. When seeking, you should
1652  * start decoding this many samples prior to your desired seek point.
1653  *
1654  * - encoding: Set by libavcodec.
1655  * - decoding: Set by libavcodec.
1656  */
1657  int delay;
1658 
1659 
1660  /* video only */
1661  /**
1662  * picture width / height.
1663  *
1664  * @note Those fields may not match the values of the last
1665  * AVFrame output by avcodec_decode_video2 due frame
1666  * reordering.
1667  *
1668  * - encoding: MUST be set by user.
1669  * - decoding: May be set by the user before opening the decoder if known e.g.
1670  * from the container. Some decoders will require the dimensions
1671  * to be set by the caller. During decoding, the decoder may
1672  * overwrite those values as required while parsing the data.
1673  */
1675 
1676  /**
1677  * Bitstream width / height, may be different from width/height e.g. when
1678  * the decoded frame is cropped before being output or lowres is enabled.
1679  *
1680  * @note Those field may not match the value of the last
1681  * AVFrame output by avcodec_receive_frame() due frame
1682  * reordering.
1683  *
1684  * - encoding: unused
1685  * - decoding: May be set by the user before opening the decoder if known
1686  * e.g. from the container. During decoding, the decoder may
1687  * overwrite those values as required while parsing the data.
1688  */
1690 
1691  /**
1692  * the number of pictures in a group of pictures, or 0 for intra_only
1693  * - encoding: Set by user.
1694  * - decoding: unused
1695  */
1697 
1698  /**
1699  * Pixel format, see AV_PIX_FMT_xxx.
1700  * May be set by the demuxer if known from headers.
1701  * May be overridden by the decoder if it knows better.
1702  *
1703  * @note This field may not match the value of the last
1704  * AVFrame output by avcodec_receive_frame() due frame
1705  * reordering.
1706  *
1707  * - encoding: Set by user.
1708  * - decoding: Set by user if known, overridden by libavcodec while
1709  * parsing the data.
1710  */
1712 
1713  /**
1714  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1715  * decoder to draw a horizontal band. It improves cache usage. Not
1716  * all codecs can do that. You must check the codec capabilities
1717  * beforehand.
1718  * When multithreading is used, it may be called from multiple threads
1719  * at the same time; threads might draw different parts of the same AVFrame,
1720  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1721  * in order.
1722  * The function is also used by hardware acceleration APIs.
1723  * It is called at least once during frame decoding to pass
1724  * the data needed for hardware render.
1725  * In that mode instead of pixel data, AVFrame points to
1726  * a structure specific to the acceleration API. The application
1727  * reads the structure and can change some fields to indicate progress
1728  * or mark state.
1729  * - encoding: unused
1730  * - decoding: Set by user.
1731  * @param height the height of the slice
1732  * @param y the y position of the slice
1733  * @param type 1->top field, 2->bottom field, 3->frame
1734  * @param offset offset into the AVFrame.data from which the slice should be read
1735  */
1737  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1738  int y, int type, int height);
1739 
1740  /**
1741  * callback to negotiate the pixelFormat
1742  * @param fmt is the list of formats which are supported by the codec,
1743  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1744  * The first is always the native one.
1745  * @note The callback may be called again immediately if initialization for
1746  * the selected (hardware-accelerated) pixel format failed.
1747  * @warning Behavior is undefined if the callback returns a value not
1748  * in the fmt list of formats.
1749  * @return the chosen format
1750  * - encoding: unused
1751  * - decoding: Set by user, if not set the native format will be chosen.
1752  */
1753  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1754 
1755  /**
1756  * maximum number of B-frames between non-B-frames
1757  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1758  * - encoding: Set by user.
1759  * - decoding: unused
1760  */
1762 
1763  /**
1764  * qscale factor between IP and B-frames
1765  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1766  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1767  * - encoding: Set by user.
1768  * - decoding: unused
1769  */
1771 
1772 #if FF_API_PRIVATE_OPT
1773  /** @deprecated use encoder private options instead */
1776 #endif
1777 
1778  /**
1779  * qscale offset between IP and B-frames
1780  * - encoding: Set by user.
1781  * - decoding: unused
1782  */
1784 
1785  /**
1786  * Size of the frame reordering buffer in the decoder.
1787  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1788  * - encoding: Set by libavcodec.
1789  * - decoding: Set by libavcodec.
1790  */
1792 
1793 #if FF_API_PRIVATE_OPT
1794  /** @deprecated use encoder private options instead */
1797 #endif
1798 
1799  /**
1800  * qscale factor between P- and I-frames
1801  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1802  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1803  * - encoding: Set by user.
1804  * - decoding: unused
1805  */
1807 
1808  /**
1809  * qscale offset between P and I-frames
1810  * - encoding: Set by user.
1811  * - decoding: unused
1812  */
1814 
1815  /**
1816  * luminance masking (0-> disabled)
1817  * - encoding: Set by user.
1818  * - decoding: unused
1819  */
1821 
1822  /**
1823  * temporary complexity masking (0-> disabled)
1824  * - encoding: Set by user.
1825  * - decoding: unused
1826  */
1828 
1829  /**
1830  * spatial complexity masking (0-> disabled)
1831  * - encoding: Set by user.
1832  * - decoding: unused
1833  */
1835 
1836  /**
1837  * p block masking (0-> disabled)
1838  * - encoding: Set by user.
1839  * - decoding: unused
1840  */
1841  float p_masking;
1842 
1843  /**
1844  * darkness masking (0-> disabled)
1845  * - encoding: Set by user.
1846  * - decoding: unused
1847  */
1849 
1850  /**
1851  * slice count
1852  * - encoding: Set by libavcodec.
1853  * - decoding: Set by user (or 0).
1854  */
1856 
1857 #if FF_API_PRIVATE_OPT
1858  /** @deprecated use encoder private options instead */
1861 #define FF_PRED_LEFT 0
1862 #define FF_PRED_PLANE 1
1863 #define FF_PRED_MEDIAN 2
1864 #endif
1865 
1866  /**
1867  * slice offsets in the frame in bytes
1868  * - encoding: Set/allocated by libavcodec.
1869  * - decoding: Set/allocated by user (or NULL).
1870  */
1872 
1873  /**
1874  * sample aspect ratio (0 if unknown)
1875  * That is the width of a pixel divided by the height of the pixel.
1876  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1877  * - encoding: Set by user.
1878  * - decoding: Set by libavcodec.
1879  */
1881 
1882  /**
1883  * motion estimation comparison function
1884  * - encoding: Set by user.
1885  * - decoding: unused
1886  */
1887  int me_cmp;
1888  /**
1889  * subpixel motion estimation comparison function
1890  * - encoding: Set by user.
1891  * - decoding: unused
1892  */
1894  /**
1895  * macroblock comparison function (not supported yet)
1896  * - encoding: Set by user.
1897  * - decoding: unused
1898  */
1899  int mb_cmp;
1900  /**
1901  * interlaced DCT comparison function
1902  * - encoding: Set by user.
1903  * - decoding: unused
1904  */
1906 #define FF_CMP_SAD 0
1907 #define FF_CMP_SSE 1
1908 #define FF_CMP_SATD 2
1909 #define FF_CMP_DCT 3
1910 #define FF_CMP_PSNR 4
1911 #define FF_CMP_BIT 5
1912 #define FF_CMP_RD 6
1913 #define FF_CMP_ZERO 7
1914 #define FF_CMP_VSAD 8
1915 #define FF_CMP_VSSE 9
1916 #define FF_CMP_NSSE 10
1917 #define FF_CMP_W53 11
1918 #define FF_CMP_W97 12
1919 #define FF_CMP_DCTMAX 13
1920 #define FF_CMP_DCT264 14
1921 #define FF_CMP_MEDIAN_SAD 15
1922 #define FF_CMP_CHROMA 256
1923 
1924  /**
1925  * ME diamond size & shape
1926  * - encoding: Set by user.
1927  * - decoding: unused
1928  */
1930 
1931  /**
1932  * amount of previous MV predictors (2a+1 x 2a+1 square)
1933  * - encoding: Set by user.
1934  * - decoding: unused
1935  */
1937 
1938 #if FF_API_PRIVATE_OPT
1939  /** @deprecated use encoder private options instead */
1941  int pre_me;
1942 #endif
1943 
1944  /**
1945  * motion estimation prepass comparison function
1946  * - encoding: Set by user.
1947  * - decoding: unused
1948  */
1950 
1951  /**
1952  * ME prepass diamond size & shape
1953  * - encoding: Set by user.
1954  * - decoding: unused
1955  */
1957 
1958  /**
1959  * subpel ME quality
1960  * - encoding: Set by user.
1961  * - decoding: unused
1962  */
1964 
1965  /**
1966  * maximum motion estimation search range in subpel units
1967  * If 0 then no limit.
1968  *
1969  * - encoding: Set by user.
1970  * - decoding: unused
1971  */
1973 
1974  /**
1975  * slice flags
1976  * - encoding: unused
1977  * - decoding: Set by user.
1978  */
1980 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1981 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1982 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1983 
1984  /**
1985  * macroblock decision mode
1986  * - encoding: Set by user.
1987  * - decoding: unused
1988  */
1990 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1991 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1992 #define FF_MB_DECISION_RD 2 ///< rate distortion
1993 
1994  /**
1995  * custom intra quantization matrix
1996  * - encoding: Set by user, can be NULL.
1997  * - decoding: Set by libavcodec.
1998  */
1999  uint16_t *intra_matrix;
2000 
2001  /**
2002  * custom inter quantization matrix
2003  * - encoding: Set by user, can be NULL.
2004  * - decoding: Set by libavcodec.
2005  */
2006  uint16_t *inter_matrix;
2007 
2008 #if FF_API_PRIVATE_OPT
2009  /** @deprecated use encoder private options instead */
2012 
2013  /** @deprecated use encoder private options instead */
2016 #endif
2017 
2018  /**
2019  * precision of the intra DC coefficient - 8
2020  * - encoding: Set by user.
2021  * - decoding: Set by libavcodec
2022  */
2024 
2025  /**
2026  * Number of macroblock rows at the top which are skipped.
2027  * - encoding: unused
2028  * - decoding: Set by user.
2029  */
2031 
2032  /**
2033  * Number of macroblock rows at the bottom which are skipped.
2034  * - encoding: unused
2035  * - decoding: Set by user.
2036  */
2038 
2039  /**
2040  * minimum MB Lagrange multiplier
2041  * - encoding: Set by user.
2042  * - decoding: unused
2043  */
2044  int mb_lmin;
2045 
2046  /**
2047  * maximum MB Lagrange multiplier
2048  * - encoding: Set by user.
2049  * - decoding: unused
2050  */
2051  int mb_lmax;
2052 
2053 #if FF_API_PRIVATE_OPT
2054  /**
2055  * @deprecated use encoder private options instead
2056  */
2059 #endif
2060 
2061  /**
2062  * - encoding: Set by user.
2063  * - decoding: unused
2064  */
2066 
2067 #if FF_API_PRIVATE_OPT
2068  /** @deprecated use encoder private options instead */
2071 #endif
2072 
2073  /**
2074  * minimum GOP size
2075  * - encoding: Set by user.
2076  * - decoding: unused
2077  */
2079 
2080  /**
2081  * number of reference frames
2082  * - encoding: Set by user.
2083  * - decoding: Set by lavc.
2084  */
2085  int refs;
2086 
2087 #if FF_API_PRIVATE_OPT
2088  /** @deprecated use encoder private options instead */
2091 #endif
2092 
2093  /**
2094  * Note: Value depends upon the compare function used for fullpel ME.
2095  * - encoding: Set by user.
2096  * - decoding: unused
2097  */
2099 
2100 #if FF_API_PRIVATE_OPT
2101  /** @deprecated use encoder private options instead */
2104 #endif
2105 
2106  /**
2107  * Chromaticity coordinates of the source primaries.
2108  * - encoding: Set by user
2109  * - decoding: Set by libavcodec
2110  */
2112 
2113  /**
2114  * Color Transfer Characteristic.
2115  * - encoding: Set by user
2116  * - decoding: Set by libavcodec
2117  */
2119 
2120  /**
2121  * YUV colorspace type.
2122  * - encoding: Set by user
2123  * - decoding: Set by libavcodec
2124  */
2126 
2127  /**
2128  * MPEG vs JPEG YUV range.
2129  * - encoding: Set by user
2130  * - decoding: Set by libavcodec
2131  */
2133 
2134  /**
2135  * This defines the location of chroma samples.
2136  * - encoding: Set by user
2137  * - decoding: Set by libavcodec
2138  */
2140 
2141  /**
2142  * Number of slices.
2143  * Indicates number of picture subdivisions. Used for parallelized
2144  * decoding.
2145  * - encoding: Set by user
2146  * - decoding: unused
2147  */
2148  int slices;
2149 
2150  /** Field order
2151  * - encoding: set by libavcodec
2152  * - decoding: Set by user.
2153  */
2155 
2156  /* audio only */
2157  int sample_rate; ///< samples per second
2158  int channels; ///< number of audio channels
2159 
2160  /**
2161  * audio sample format
2162  * - encoding: Set by user.
2163  * - decoding: Set by libavcodec.
2164  */
2165  enum AVSampleFormat sample_fmt; ///< sample format
2166 
2167  /* The following data should not be initialized. */
2168  /**
2169  * Number of samples per channel in an audio frame.
2170  *
2171  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2172  * except the last must contain exactly frame_size samples per channel.
2173  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2174  * frame size is not restricted.
2175  * - decoding: may be set by some decoders to indicate constant frame size
2176  */
2178 
2179  /**
2180  * Frame counter, set by libavcodec.
2181  *
2182  * - decoding: total number of frames returned from the decoder so far.
2183  * - encoding: total number of frames passed to the encoder so far.
2184  *
2185  * @note the counter is not incremented if encoding/decoding resulted in
2186  * an error.
2187  */
2189 
2190  /**
2191  * number of bytes per packet if constant and known or 0
2192  * Used by some WAV based audio codecs.
2193  */
2195 
2196  /**
2197  * Audio cutoff bandwidth (0 means "automatic")
2198  * - encoding: Set by user.
2199  * - decoding: unused
2200  */
2201  int cutoff;
2202 
2203  /**
2204  * Audio channel layout.
2205  * - encoding: set by user.
2206  * - decoding: set by user, may be overwritten by libavcodec.
2207  */
2208  uint64_t channel_layout;
2209 
2210  /**
2211  * Request decoder to use this channel layout if it can (0 for default)
2212  * - encoding: unused
2213  * - decoding: Set by user.
2214  */
2216 
2217  /**
2218  * Type of service that the audio stream conveys.
2219  * - encoding: Set by user.
2220  * - decoding: Set by libavcodec.
2221  */
2223 
2224  /**
2225  * desired sample format
2226  * - encoding: Not used.
2227  * - decoding: Set by user.
2228  * Decoder will decode to this format if it can.
2229  */
2231 
2232  /**
2233  * This callback is called at the beginning of each frame to get data
2234  * buffer(s) for it. There may be one contiguous buffer for all the data or
2235  * there may be a buffer per each data plane or anything in between. What
2236  * this means is, you may set however many entries in buf[] you feel necessary.
2237  * Each buffer must be reference-counted using the AVBuffer API (see description
2238  * of buf[] below).
2239  *
2240  * The following fields will be set in the frame before this callback is
2241  * called:
2242  * - format
2243  * - width, height (video only)
2244  * - sample_rate, channel_layout, nb_samples (audio only)
2245  * Their values may differ from the corresponding values in
2246  * AVCodecContext. This callback must use the frame values, not the codec
2247  * context values, to calculate the required buffer size.
2248  *
2249  * This callback must fill the following fields in the frame:
2250  * - data[]
2251  * - linesize[]
2252  * - extended_data:
2253  * * if the data is planar audio with more than 8 channels, then this
2254  * callback must allocate and fill extended_data to contain all pointers
2255  * to all data planes. data[] must hold as many pointers as it can.
2256  * extended_data must be allocated with av_malloc() and will be freed in
2257  * av_frame_unref().
2258  * * otherwise extended_data must point to data
2259  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2260  * the frame's data and extended_data pointers must be contained in these. That
2261  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2262  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2263  * and av_buffer_ref().
2264  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2265  * this callback and filled with the extra buffers if there are more
2266  * buffers than buf[] can hold. extended_buf will be freed in
2267  * av_frame_unref().
2268  *
2269  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2270  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2271  * some other means.
2272  *
2273  * Each data plane must be aligned to the maximum required by the target
2274  * CPU.
2275  *
2276  * @see avcodec_default_get_buffer2()
2277  *
2278  * Video:
2279  *
2280  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2281  * (read and/or written to if it is writable) later by libavcodec.
2282  *
2283  * avcodec_align_dimensions2() should be used to find the required width and
2284  * height, as they normally need to be rounded up to the next multiple of 16.
2285  *
2286  * Some decoders do not support linesizes changing between frames.
2287  *
2288  * If frame multithreading is used and thread_safe_callbacks is set,
2289  * this callback may be called from a different thread, but not from more
2290  * than one at once. Does not need to be reentrant.
2291  *
2292  * @see avcodec_align_dimensions2()
2293  *
2294  * Audio:
2295  *
2296  * Decoders request a buffer of a particular size by setting
2297  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2298  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2299  * to a smaller value in the output frame.
2300  *
2301  * As a convenience, av_samples_get_buffer_size() and
2302  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2303  * functions to find the required data size and to fill data pointers and
2304  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2305  * since all planes must be the same size.
2306  *
2307  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2308  *
2309  * - encoding: unused
2310  * - decoding: Set by libavcodec, user can override.
2311  */
2313 
2314  /**
2315  * If non-zero, the decoded audio and video frames returned from
2316  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2317  * and are valid indefinitely. The caller must free them with
2318  * av_frame_unref() when they are not needed anymore.
2319  * Otherwise, the decoded frames must not be freed by the caller and are
2320  * only valid until the next decode call.
2321  *
2322  * This is always automatically enabled if avcodec_receive_frame() is used.
2323  *
2324  * - encoding: unused
2325  * - decoding: set by the caller before avcodec_open2().
2326  */
2329 
2330  /* - encoding parameters */
2331  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2332  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2333 
2334  /**
2335  * minimum quantizer
2336  * - encoding: Set by user.
2337  * - decoding: unused
2338  */
2339  int qmin;
2340 
2341  /**
2342  * maximum quantizer
2343  * - encoding: Set by user.
2344  * - decoding: unused
2345  */
2346  int qmax;
2347 
2348  /**
2349  * maximum quantizer difference between frames
2350  * - encoding: Set by user.
2351  * - decoding: unused
2352  */
2354 
2355  /**
2356  * decoder bitstream buffer size
2357  * - encoding: Set by user.
2358  * - decoding: unused
2359  */
2361 
2362  /**
2363  * ratecontrol override, see RcOverride
2364  * - encoding: Allocated/set/freed by user.
2365  * - decoding: unused
2366  */
2369 
2370  /**
2371  * maximum bitrate
2372  * - encoding: Set by user.
2373  * - decoding: Set by user, may be overwritten by libavcodec.
2374  */
2375  int64_t rc_max_rate;
2376 
2377  /**
2378  * minimum bitrate
2379  * - encoding: Set by user.
2380  * - decoding: unused
2381  */
2382  int64_t rc_min_rate;
2383 
2384  /**
2385  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2386  * - encoding: Set by user.
2387  * - decoding: unused.
2388  */
2390 
2391  /**
2392  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2393  * - encoding: Set by user.
2394  * - decoding: unused.
2395  */
2397 
2398  /**
2399  * Number of bits which should be loaded into the rc buffer before decoding starts.
2400  * - encoding: Set by user.
2401  * - decoding: unused
2402  */
2404 
2405 #if FF_API_CODER_TYPE
2406 #define FF_CODER_TYPE_VLC 0
2407 #define FF_CODER_TYPE_AC 1
2408 #define FF_CODER_TYPE_RAW 2
2409 #define FF_CODER_TYPE_RLE 3
2410  /**
2411  * @deprecated use encoder private options instead
2412  */
2415 #endif /* FF_API_CODER_TYPE */
2416 
2417 #if FF_API_PRIVATE_OPT
2418  /** @deprecated use encoder private options instead */
2421 #endif
2422 
2423 #if FF_API_PRIVATE_OPT
2424  /** @deprecated use encoder private options instead */
2427 
2428  /** @deprecated use encoder private options instead */
2431 
2432  /** @deprecated use encoder private options instead */
2435 
2436  /** @deprecated use encoder private options instead */
2439 #endif /* FF_API_PRIVATE_OPT */
2440 
2441  /**
2442  * trellis RD quantization
2443  * - encoding: Set by user.
2444  * - decoding: unused
2445  */
2446  int trellis;
2447 
2448 #if FF_API_PRIVATE_OPT
2449  /** @deprecated use encoder private options instead */
2452 
2453  /** @deprecated use encoder private options instead */
2456 
2457  /** @deprecated use encoder private options instead */
2460 #endif
2461 
2462 #if FF_API_RTP_CALLBACK
2463  /**
2464  * @deprecated unused
2465  */
2466  /* The RTP callback: This function is called */
2467  /* every time the encoder has a packet to send. */
2468  /* It depends on the encoder if the data starts */
2469  /* with a Start Code (it should). H.263 does. */
2470  /* mb_nb contains the number of macroblocks */
2471  /* encoded in the RTP payload. */
2473  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2474 #endif
2475 
2476 #if FF_API_PRIVATE_OPT
2477  /** @deprecated use encoder private options instead */
2479  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2480  /* do its best to deliver a chunk with size */
2481  /* below rtp_payload_size, the chunk will start */
2482  /* with a start code on some codecs like H.263. */
2483  /* This doesn't take account of any particular */
2484  /* headers inside the transmitted RTP payload. */
2485 #endif
2486 
2487 #if FF_API_STAT_BITS
2488  /* statistics, used for 2-pass encoding */
2490  int mv_bits;
2498  int i_count;
2500  int p_count;
2505 
2506  /** @deprecated this field is unused */
2509 #endif
2510 
2511  /**
2512  * pass1 encoding statistics output buffer
2513  * - encoding: Set by libavcodec.
2514  * - decoding: unused
2515  */
2516  char *stats_out;
2517 
2518  /**
2519  * pass2 encoding statistics input buffer
2520  * Concatenated stuff from stats_out of pass1 should be placed here.
2521  * - encoding: Allocated/set/freed by user.
2522  * - decoding: unused
2523  */
2524  char *stats_in;
2525 
2526  /**
2527  * Work around bugs in encoders which sometimes cannot be detected automatically.
2528  * - encoding: Set by user
2529  * - decoding: Set by user
2530  */
2532 #define FF_BUG_AUTODETECT 1 ///< autodetection
2533 #define FF_BUG_XVID_ILACE 4
2534 #define FF_BUG_UMP4 8
2535 #define FF_BUG_NO_PADDING 16
2536 #define FF_BUG_AMV 32
2537 #define FF_BUG_QPEL_CHROMA 64
2538 #define FF_BUG_STD_QPEL 128
2539 #define FF_BUG_QPEL_CHROMA2 256
2540 #define FF_BUG_DIRECT_BLOCKSIZE 512
2541 #define FF_BUG_EDGE 1024
2542 #define FF_BUG_HPEL_CHROMA 2048
2543 #define FF_BUG_DC_CLIP 4096
2544 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2545 #define FF_BUG_TRUNCATED 16384
2546 #define FF_BUG_IEDGE 32768
2547 
2548  /**
2549  * strictly follow the standard (MPEG-4, ...).
2550  * - encoding: Set by user.
2551  * - decoding: Set by user.
2552  * Setting this to STRICT or higher means the encoder and decoder will
2553  * generally do stupid things, whereas setting it to unofficial or lower
2554  * will mean the encoder might produce output that is not supported by all
2555  * spec-compliant decoders. Decoders don't differentiate between normal,
2556  * unofficial and experimental (that is, they always try to decode things
2557  * when they can) unless they are explicitly asked to behave stupidly
2558  * (=strictly conform to the specs)
2559  */
2561 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2562 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2563 #define FF_COMPLIANCE_NORMAL 0
2564 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2565 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2566 
2567  /**
2568  * error concealment flags
2569  * - encoding: unused
2570  * - decoding: Set by user.
2571  */
2573 #define FF_EC_GUESS_MVS 1
2574 #define FF_EC_DEBLOCK 2
2575 #define FF_EC_FAVOR_INTER 256
2576 
2577  /**
2578  * debug
2579  * - encoding: Set by user.
2580  * - decoding: Set by user.
2581  */
2582  int debug;
2583 #define FF_DEBUG_PICT_INFO 1
2584 #define FF_DEBUG_RC 2
2585 #define FF_DEBUG_BITSTREAM 4
2586 #define FF_DEBUG_MB_TYPE 8
2587 #define FF_DEBUG_QP 16
2588 #if FF_API_DEBUG_MV
2589 /**
2590  * @deprecated this option does nothing
2591  */
2592 #define FF_DEBUG_MV 32
2593 #endif
2594 #define FF_DEBUG_DCT_COEFF 0x00000040
2595 #define FF_DEBUG_SKIP 0x00000080
2596 #define FF_DEBUG_STARTCODE 0x00000100
2597 #define FF_DEBUG_ER 0x00000400
2598 #define FF_DEBUG_MMCO 0x00000800
2599 #define FF_DEBUG_BUGS 0x00001000
2600 #if FF_API_DEBUG_MV
2601 #define FF_DEBUG_VIS_QP 0x00002000
2602 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2603 #endif
2604 #define FF_DEBUG_BUFFERS 0x00008000
2605 #define FF_DEBUG_THREADS 0x00010000
2606 #define FF_DEBUG_GREEN_MD 0x00800000
2607 #define FF_DEBUG_NOMC 0x01000000
2608 
2609 #if FF_API_DEBUG_MV
2610  /**
2611  * debug
2612  * - encoding: Set by user.
2613  * - decoding: Set by user.
2614  */
2615  int debug_mv;
2616 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2617 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2618 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2619 #endif
2620 
2621  /**
2622  * Error recognition; may misdetect some more or less valid parts as errors.
2623  * - encoding: unused
2624  * - decoding: Set by user.
2625  */
2627 
2628 /**
2629  * Verify checksums embedded in the bitstream (could be of either encoded or
2630  * decoded data, depending on the codec) and print an error message on mismatch.
2631  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2632  * decoder returning an error.
2633  */
2634 #define AV_EF_CRCCHECK (1<<0)
2635 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2636 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2637 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2638 
2639 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2640 #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
2641 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2642 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2643 
2644 
2645  /**
2646  * opaque 64-bit number (generally a PTS) that will be reordered and
2647  * output in AVFrame.reordered_opaque
2648  * - encoding: unused
2649  * - decoding: Set by user.
2650  */
2652 
2653  /**
2654  * Hardware accelerator in use
2655  * - encoding: unused.
2656  * - decoding: Set by libavcodec
2657  */
2658  const struct AVHWAccel *hwaccel;
2659 
2660  /**
2661  * Hardware accelerator context.
2662  * For some hardware accelerators, a global context needs to be
2663  * provided by the user. In that case, this holds display-dependent
2664  * data FFmpeg cannot instantiate itself. Please refer to the
2665  * FFmpeg HW accelerator documentation to know how to fill this
2666  * is. e.g. for VA API, this is a struct vaapi_context.
2667  * - encoding: unused
2668  * - decoding: Set by user
2669  */
2671 
2672  /**
2673  * error
2674  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2675  * - decoding: unused
2676  */
2678 
2679  /**
2680  * DCT algorithm, see FF_DCT_* below
2681  * - encoding: Set by user.
2682  * - decoding: unused
2683  */
2685 #define FF_DCT_AUTO 0
2686 #define FF_DCT_FASTINT 1
2687 #define FF_DCT_INT 2
2688 #define FF_DCT_MMX 3
2689 #define FF_DCT_ALTIVEC 5
2690 #define FF_DCT_FAAN 6
2691 
2692  /**
2693  * IDCT algorithm, see FF_IDCT_* below.
2694  * - encoding: Set by user.
2695  * - decoding: Set by user.
2696  */
2698 #define FF_IDCT_AUTO 0
2699 #define FF_IDCT_INT 1
2700 #define FF_IDCT_SIMPLE 2
2701 #define FF_IDCT_SIMPLEMMX 3
2702 #define FF_IDCT_ARM 7
2703 #define FF_IDCT_ALTIVEC 8
2704 #define FF_IDCT_SIMPLEARM 10
2705 #define FF_IDCT_XVID 14
2706 #define FF_IDCT_SIMPLEARMV5TE 16
2707 #define FF_IDCT_SIMPLEARMV6 17
2708 #define FF_IDCT_FAAN 20
2709 #define FF_IDCT_SIMPLENEON 22
2710 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2711 #define FF_IDCT_SIMPLEAUTO 128
2712 
2713  /**
2714  * bits per sample/pixel from the demuxer (needed for huffyuv).
2715  * - encoding: Set by libavcodec.
2716  * - decoding: Set by user.
2717  */
2719 
2720  /**
2721  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2722  * - encoding: set by user.
2723  * - decoding: set by libavcodec.
2724  */
2726 
2727 #if FF_API_LOWRES
2728  /**
2729  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2730  * - encoding: unused
2731  * - decoding: Set by user.
2732  */
2733  int lowres;
2734 #endif
2735 
2736 #if FF_API_CODED_FRAME
2737  /**
2738  * the picture in the bitstream
2739  * - encoding: Set by libavcodec.
2740  * - decoding: unused
2741  *
2742  * @deprecated use the quality factor packet side data instead
2743  */
2745 #endif
2746 
2747  /**
2748  * thread count
2749  * is used to decide how many independent tasks should be passed to execute()
2750  * - encoding: Set by user.
2751  * - decoding: Set by user.
2752  */
2754 
2755  /**
2756  * Which multithreading methods to use.
2757  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2758  * so clients which cannot provide future frames should not use it.
2759  *
2760  * - encoding: Set by user, otherwise the default is used.
2761  * - decoding: Set by user, otherwise the default is used.
2762  */
2764 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2765 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2766 
2767  /**
2768  * Which multithreading methods are in use by the codec.
2769  * - encoding: Set by libavcodec.
2770  * - decoding: Set by libavcodec.
2771  */
2773 
2774  /**
2775  * Set by the client if its custom get_buffer() callback can be called
2776  * synchronously from another thread, which allows faster multithreaded decoding.
2777  * draw_horiz_band() will be called from other threads regardless of this setting.
2778  * Ignored if the default get_buffer() is used.
2779  * - encoding: Set by user.
2780  * - decoding: Set by user.
2781  */
2783 
2784  /**
2785  * The codec may call this to execute several independent things.
2786  * It will return only after finishing all tasks.
2787  * The user may replace this with some multithreaded implementation,
2788  * the default implementation will execute the parts serially.
2789  * @param count the number of things to execute
2790  * - encoding: Set by libavcodec, user can override.
2791  * - decoding: Set by libavcodec, user can override.
2792  */
2793  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2794 
2795  /**
2796  * The codec may call this to execute several independent things.
2797  * It will return only after finishing all tasks.
2798  * The user may replace this with some multithreaded implementation,
2799  * the default implementation will execute the parts serially.
2800  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2801  * @param c context passed also to func
2802  * @param count the number of things to execute
2803  * @param arg2 argument passed unchanged to func
2804  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2805  * @param func function that will be called count times, with jobnr from 0 to count-1.
2806  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2807  * two instances of func executing at the same time will have the same threadnr.
2808  * @return always 0 currently, but code should handle a future improvement where when any call to func
2809  * returns < 0 no further calls to func may be done and < 0 is returned.
2810  * - encoding: Set by libavcodec, user can override.
2811  * - decoding: Set by libavcodec, user can override.
2812  */
2813  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2814 
2815  /**
2816  * noise vs. sse weight for the nsse comparison function
2817  * - encoding: Set by user.
2818  * - decoding: unused
2819  */
2821 
2822  /**
2823  * profile
2824  * - encoding: Set by user.
2825  * - decoding: Set by libavcodec.
2826  */
2827  int profile;
2828 #define FF_PROFILE_UNKNOWN -99
2829 #define FF_PROFILE_RESERVED -100
2830 
2831 #define FF_PROFILE_AAC_MAIN 0
2832 #define FF_PROFILE_AAC_LOW 1
2833 #define FF_PROFILE_AAC_SSR 2
2834 #define FF_PROFILE_AAC_LTP 3
2835 #define FF_PROFILE_AAC_HE 4
2836 #define FF_PROFILE_AAC_HE_V2 28
2837 #define FF_PROFILE_AAC_LD 22
2838 #define FF_PROFILE_AAC_ELD 38
2839 #define FF_PROFILE_MPEG2_AAC_LOW 128
2840 #define FF_PROFILE_MPEG2_AAC_HE 131
2841 
2842 #define FF_PROFILE_DNXHD 0
2843 #define FF_PROFILE_DNXHR_LB 1
2844 #define FF_PROFILE_DNXHR_SQ 2
2845 #define FF_PROFILE_DNXHR_HQ 3
2846 #define FF_PROFILE_DNXHR_HQX 4
2847 #define FF_PROFILE_DNXHR_444 5
2848 
2849 #define FF_PROFILE_DTS 20
2850 #define FF_PROFILE_DTS_ES 30
2851 #define FF_PROFILE_DTS_96_24 40
2852 #define FF_PROFILE_DTS_HD_HRA 50
2853 #define FF_PROFILE_DTS_HD_MA 60
2854 #define FF_PROFILE_DTS_EXPRESS 70
2855 
2856 #define FF_PROFILE_MPEG2_422 0
2857 #define FF_PROFILE_MPEG2_HIGH 1
2858 #define FF_PROFILE_MPEG2_SS 2
2859 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2860 #define FF_PROFILE_MPEG2_MAIN 4
2861 #define FF_PROFILE_MPEG2_SIMPLE 5
2862 
2863 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2864 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2865 
2866 #define FF_PROFILE_H264_BASELINE 66
2867 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2868 #define FF_PROFILE_H264_MAIN 77
2869 #define FF_PROFILE_H264_EXTENDED 88
2870 #define FF_PROFILE_H264_HIGH 100
2871 #define FF_PROFILE_H264_HIGH_10 110
2872 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2873 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2874 #define FF_PROFILE_H264_HIGH_422 122
2875 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2876 #define FF_PROFILE_H264_STEREO_HIGH 128
2877 #define FF_PROFILE_H264_HIGH_444 144
2878 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2879 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2880 #define FF_PROFILE_H264_CAVLC_444 44
2881 
2882 #define FF_PROFILE_VC1_SIMPLE 0
2883 #define FF_PROFILE_VC1_MAIN 1
2884 #define FF_PROFILE_VC1_COMPLEX 2
2885 #define FF_PROFILE_VC1_ADVANCED 3
2886 
2887 #define FF_PROFILE_MPEG4_SIMPLE 0
2888 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2889 #define FF_PROFILE_MPEG4_CORE 2
2890 #define FF_PROFILE_MPEG4_MAIN 3
2891 #define FF_PROFILE_MPEG4_N_BIT 4
2892 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2893 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2894 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2895 #define FF_PROFILE_MPEG4_HYBRID 8
2896 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2897 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2898 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2899 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2900 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2901 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2902 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2903 
2904 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2905 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2906 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2907 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2908 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2909 
2910 #define FF_PROFILE_VP9_0 0
2911 #define FF_PROFILE_VP9_1 1
2912 #define FF_PROFILE_VP9_2 2
2913 #define FF_PROFILE_VP9_3 3
2914 
2915 #define FF_PROFILE_HEVC_MAIN 1
2916 #define FF_PROFILE_HEVC_MAIN_10 2
2917 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2918 #define FF_PROFILE_HEVC_REXT 4
2919 
2920  /**
2921  * level
2922  * - encoding: Set by user.
2923  * - decoding: Set by libavcodec.
2924  */
2925  int level;
2926 #define FF_LEVEL_UNKNOWN -99
2927 
2928  /**
2929  * Skip loop filtering for selected frames.
2930  * - encoding: unused
2931  * - decoding: Set by user.
2932  */
2934 
2935  /**
2936  * Skip IDCT/dequantization for selected frames.
2937  * - encoding: unused
2938  * - decoding: Set by user.
2939  */
2941 
2942  /**
2943  * Skip decoding for selected frames.
2944  * - encoding: unused
2945  * - decoding: Set by user.
2946  */
2948 
2949  /**
2950  * Header containing style information for text subtitles.
2951  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2952  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2953  * the Format line following. It shouldn't include any Dialogue line.
2954  * - encoding: Set/allocated/freed by user (before avcodec_open2())
2955  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2956  */
2959 
2960 #if FF_API_VBV_DELAY
2961  /**
2962  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2963  * Used for compliant TS muxing.
2964  * - encoding: Set by libavcodec.
2965  * - decoding: unused.
2966  * @deprecated this value is now exported as a part of
2967  * AV_PKT_DATA_CPB_PROPERTIES packet side data
2968  */
2970  uint64_t vbv_delay;
2971 #endif
2972 
2973 #if FF_API_SIDEDATA_ONLY_PKT
2974  /**
2975  * Encoding only and set by default. Allow encoders to output packets
2976  * that do not contain any encoded data, only side data.
2977  *
2978  * Some encoders need to output such packets, e.g. to update some stream
2979  * parameters at the end of encoding.
2980  *
2981  * @deprecated this field disables the default behaviour and
2982  * it is kept only for compatibility.
2983  */
2986 #endif
2987 
2988  /**
2989  * Audio only. The number of "priming" samples (padding) inserted by the
2990  * encoder at the beginning of the audio. I.e. this number of leading
2991  * decoded samples must be discarded by the caller to get the original audio
2992  * without leading padding.
2993  *
2994  * - decoding: unused
2995  * - encoding: Set by libavcodec. The timestamps on the output packets are
2996  * adjusted by the encoder so that they always refer to the
2997  * first sample of the data actually contained in the packet,
2998  * including any added padding. E.g. if the timebase is
2999  * 1/samplerate and the timestamp of the first input sample is
3000  * 0, the timestamp of the first output packet will be
3001  * -initial_padding.
3002  */
3004 
3005  /**
3006  * - decoding: For codecs that store a framerate value in the compressed
3007  * bitstream, the decoder may export it here. { 0, 1} when
3008  * unknown.
3009  * - encoding: May be used to signal the framerate of CFR content to an
3010  * encoder.
3011  */
3013 
3014  /**
3015  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3016  * - encoding: unused.
3017  * - decoding: Set by libavcodec before calling get_format()
3018  */
3020 
3021  /**
3022  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3023  * - encoding unused.
3024  * - decoding set by user.
3025  */
3027 
3028  /**
3029  * AVCodecDescriptor
3030  * - encoding: unused.
3031  * - decoding: set by libavcodec.
3032  */
3034 
3035 #if !FF_API_LOWRES
3036  /**
3037  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3038  * - encoding: unused
3039  * - decoding: Set by user.
3040  */
3041  int lowres;
3042 #endif
3043 
3044  /**
3045  * Current statistics for PTS correction.
3046  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3047  * - encoding: unused
3048  */
3049  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3050  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3051  int64_t pts_correction_last_pts; /// PTS of the last frame
3052  int64_t pts_correction_last_dts; /// DTS of the last frame
3053 
3054  /**
3055  * Character encoding of the input subtitles file.
3056  * - decoding: set by user
3057  * - encoding: unused
3058  */
3060 
3061  /**
3062  * Subtitles character encoding mode. Formats or codecs might be adjusting
3063  * this setting (if they are doing the conversion themselves for instance).
3064  * - decoding: set by libavcodec
3065  * - encoding: unused
3066  */
3068 #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)
3069 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3070 #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
3071 
3072  /**
3073  * Skip processing alpha if supported by codec.
3074  * Note that if the format uses pre-multiplied alpha (common with VP6,
3075  * and recommended due to better video quality/compression)
3076  * the image will look as if alpha-blended onto a black background.
3077  * However for formats that do not use pre-multiplied alpha
3078  * there might be serious artefacts (though e.g. libswscale currently
3079  * assumes pre-multiplied alpha anyway).
3080  *
3081  * - decoding: set by user
3082  * - encoding: unused
3083  */
3085 
3086  /**
3087  * Number of samples to skip after a discontinuity
3088  * - decoding: unused
3089  * - encoding: set by libavcodec
3090  */
3092 
3093 #if !FF_API_DEBUG_MV
3094  /**
3095  * debug motion vectors
3096  * - encoding: Set by user.
3097  * - decoding: Set by user.
3098  */
3100 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3101 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3102 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3103 #endif
3104 
3105  /**
3106  * custom intra quantization matrix
3107  * - encoding: Set by user, can be NULL.
3108  * - decoding: unused.
3109  */
3111 
3112  /**
3113  * dump format separator.
3114  * can be ", " or "\n " or anything else
3115  * - encoding: Set by user.
3116  * - decoding: Set by user.
3117  */
3119 
3120  /**
3121  * ',' separated list of allowed decoders.
3122  * If NULL then all are allowed
3123  * - encoding: unused
3124  * - decoding: set by user
3125  */
3127 
3128  /**
3129  * Properties of the stream that gets decoded
3130  * - encoding: unused
3131  * - decoding: set by libavcodec
3132  */
3133  unsigned properties;
3134 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3135 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3136 
3137  /**
3138  * Additional data associated with the entire coded stream.
3139  *
3140  * - decoding: unused
3141  * - encoding: may be set by libavcodec after avcodec_open2().
3142  */
3145 
3146  /**
3147  * A reference to the AVHWFramesContext describing the input (for encoding)
3148  * or output (decoding) frames. The reference is set by the caller and
3149  * afterwards owned (and freed) by libavcodec - it should never be read by
3150  * the caller after being set.
3151  *
3152  * - decoding: This field should be set by the caller from the get_format()
3153  * callback. The previous reference (if any) will always be
3154  * unreffed by libavcodec before the get_format() call.
3155  *
3156  * If the default get_buffer2() is used with a hwaccel pixel
3157  * format, then this AVHWFramesContext will be used for
3158  * allocating the frame buffers.
3159  *
3160  * - encoding: For hardware encoders configured to use a hwaccel pixel
3161  * format, this field should be set by the caller to a reference
3162  * to the AVHWFramesContext describing input frames.
3163  * AVHWFramesContext.format must be equal to
3164  * AVCodecContext.pix_fmt.
3165  *
3166  * This field should be set before avcodec_open2() is called.
3167  */
3169 
3170  /**
3171  * Control the form of AVSubtitle.rects[N]->ass
3172  * - decoding: set by user
3173  * - encoding: unused
3174  */
3176 #define FF_SUB_TEXT_FMT_ASS 0
3177 #if FF_API_ASS_TIMING
3178 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3179 #endif
3180 
3181  /**
3182  * Audio only. The amount of padding (in samples) appended by the encoder to
3183  * the end of the audio. I.e. this number of decoded samples must be
3184  * discarded by the caller from the end of the stream to get the original
3185  * audio without any trailing padding.
3186  *
3187  * - decoding: unused
3188  * - encoding: unused
3189  */
3191 
3192  /**
3193  * The number of pixels per image to maximally accept.
3194  *
3195  * - decoding: set by user
3196  * - encoding: set by user
3197  */
3198  int64_t max_pixels;
3199 
3200  /**
3201  * A reference to the AVHWDeviceContext describing the device which will
3202  * be used by a hardware encoder/decoder. The reference is set by the
3203  * caller and afterwards owned (and freed) by libavcodec.
3204  *
3205  * This should be used if either the codec device does not require
3206  * hardware frames or any that are used are to be allocated internally by
3207  * libavcodec. If the user wishes to supply any of the frames used as
3208  * encoder input or decoder output then hw_frames_ctx should be used
3209  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3210  * field will be ignored while decoding the associated stream segment, but
3211  * may again be used on a following one after another get_format() call.
3212  *
3213  * For both encoders and decoders this field should be set before
3214  * avcodec_open2() is called and must not be written to thereafter.
3215  *
3216  * Note that some decoders may require this field to be set initially in
3217  * order to support hw_frames_ctx at all - in that case, all frames
3218  * contexts used must be created on the same device.
3219  */
3221 
3222  /**
3223  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3224  * decoding (if active).
3225  * - encoding: unused
3226  * - decoding: Set by user (either before avcodec_open2(), or in the
3227  * AVCodecContext.get_format callback)
3228  */
3230 
3231  /**
3232  * Video decoding only. Certain video codecs support cropping, meaning that
3233  * only a sub-rectangle of the decoded frame is intended for display. This
3234  * option controls how cropping is handled by libavcodec.
3235  *
3236  * When set to 1 (the default), libavcodec will apply cropping internally.
3237  * I.e. it will modify the output frame width/height fields and offset the
3238  * data pointers (only by as much as possible while preserving alignment, or
3239  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3240  * the frames output by the decoder refer only to the cropped area. The
3241  * crop_* fields of the output frames will be zero.
3242  *
3243  * When set to 0, the width/height fields of the output frames will be set
3244  * to the coded dimensions and the crop_* fields will describe the cropping
3245  * rectangle. Applying the cropping is left to the caller.
3246  *
3247  * @warning When hardware acceleration with opaque output frames is used,
3248  * libavcodec is unable to apply cropping from the top/left border.
3249  *
3250  * @note when this option is set to zero, the width/height fields of the
3251  * AVCodecContext and output AVFrames have different meanings. The codec
3252  * context fields store display dimensions (with the coded dimensions in
3253  * coded_width/height), while the frame fields store the coded dimensions
3254  * (with the display dimensions being determined by the crop_* fields).
3255  */
3257 } AVCodecContext;
3258 
3259 #if FF_API_CODEC_GET_SET
3260 /**
3261  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3262  * compatibility, and do not need to be used anymore.
3263  */
3268 
3273 
3275 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3276 
3277 #if FF_API_LOWRES
3279 int av_codec_get_lowres(const AVCodecContext *avctx);
3281 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3282 #endif
3283 
3285 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3287 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3288 
3290 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3292 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3293 #endif
3294 
3295 /**
3296  * AVProfile.
3297  */
3298 typedef struct AVProfile {
3299  int profile;
3300  const char *name; ///< short name for the profile
3301 } AVProfile;
3302 
3303 enum {
3304  /**
3305  * The codec supports this format via the hw_device_ctx interface.
3306  *
3307  * When selecting this format, AVCodecContext.hw_device_ctx should
3308  * have been set to a device of the specified type before calling
3309  * avcodec_open2().
3310  */
3312  /**
3313  * The codec supports this format via the hw_frames_ctx interface.
3314  *
3315  * When selecting this format for a decoder,
3316  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3317  * context inside the get_format() callback. The frames context
3318  * must have been created on a device of the specified type.
3319  */
3321  /**
3322  * The codec supports this format by some internal method.
3323  *
3324  * This format can be selected without any additional configuration -
3325  * no device or frames context is required.
3326  */
3328  /**
3329  * The codec supports this format by some ad-hoc method.
3330  *
3331  * Additional settings and/or function calls are required. See the
3332  * codec-specific documentation for details. (Methods requiring
3333  * this sort of configuration are deprecated and others should be
3334  * used in preference.)
3335  */
3337 };
3338 
3339 typedef struct AVCodecHWConfig {
3340  /**
3341  * A hardware pixel format which the codec can use.
3342  */
3344  /**
3345  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3346  * setup methods which can be used with this configuration.
3347  */
3348  int methods;
3349  /**
3350  * The device type associated with the configuration.
3351  *
3352  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3353  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3354  */
3356 } AVCodecHWConfig;
3357 
3358 typedef struct AVCodecDefault AVCodecDefault;
3359 
3360 struct AVSubtitle;
3361 
3362 /**
3363  * AVCodec.
3364  */
3365 typedef struct AVCodec {
3366  /**
3367  * Name of the codec implementation.
3368  * The name is globally unique among encoders and among decoders (but an
3369  * encoder and a decoder can share the same name).
3370  * This is the primary way to find a codec from the user perspective.
3371  */
3372  const char *name;
3373  /**
3374  * Descriptive name for the codec, meant to be more human readable than name.
3375  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3376  */
3377  const char *long_name;
3380  /**
3381  * Codec capabilities.
3382  * see AV_CODEC_CAP_*
3383  */
3385  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3386  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3387  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3388  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3389  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3390  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3391  const AVClass *priv_class; ///< AVClass for the private context
3392  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3393 
3394  /**
3395  * Group name of the codec implementation.
3396  * This is a short symbolic name of the wrapper backing this codec. A
3397  * wrapper uses some kind of external implementation for the codec, such
3398  * as an external library, or a codec implementation provided by the OS or
3399  * the hardware.
3400  * If this field is NULL, this is a builtin, libavcodec native codec.
3401  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3402  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3403  */
3404  const char *wrapper_name;
3405 
3406  /*****************************************************************
3407  * No fields below this line are part of the public API. They
3408  * may not be used outside of libavcodec and can be changed and
3409  * removed at will.
3410  * New public fields should be added right above.
3411  *****************************************************************
3412  */
3414  struct AVCodec *next;
3415  /**
3416  * @name Frame-level threading support functions
3417  * @{
3418  */
3419  /**
3420  * If defined, called on thread contexts when they are created.
3421  * If the codec allocates writable tables in init(), re-allocate them here.
3422  * priv_data will be set to a copy of the original.
3423  */
3425  /**
3426  * Copy necessary context variables from a previous thread context to the current one.
3427  * If not defined, the next thread will start automatically; otherwise, the codec
3428  * must call ff_thread_finish_setup().
3429  *
3430  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3431  */
3433  /** @} */
3434 
3435  /**
3436  * Private codec-specific defaults.
3437  */
3439 
3440  /**
3441  * Initialize codec static data, called from avcodec_register().
3442  */
3443  void (*init_static_data)(struct AVCodec *codec);
3444 
3446  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3447  const struct AVSubtitle *sub);
3448  /**
3449  * Encode data to an AVPacket.
3450  *
3451  * @param avctx codec context
3452  * @param avpkt output AVPacket (may contain a user-provided buffer)
3453  * @param[in] frame AVFrame containing the raw data to be encoded
3454  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3455  * non-empty packet was returned in avpkt.
3456  * @return 0 on success, negative error code on failure
3457  */
3458  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3459  int *got_packet_ptr);
3460  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3462  /**
3463  * Encode API with decoupled packet/frame dataflow. The API is the
3464  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3465  * that:
3466  * - never called if the codec is closed or the wrong type,
3467  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3468  * - only one drain frame is ever passed down,
3469  */
3472 
3473  /**
3474  * Decode API with decoupled packet/frame dataflow. This function is called
3475  * to get one output frame. It should call ff_decode_get_packet() to obtain
3476  * input data.
3477  */
3479  /**
3480  * Flush buffers.
3481  * Will be called when seeking
3482  */
3484  /**
3485  * Internal codec capabilities.
3486  * See FF_CODEC_CAP_* in internal.h
3487  */
3489 
3490  /**
3491  * Decoding only, a comma-separated list of bitstream filters to apply to
3492  * packets before decoding.
3493  */
3494  const char *bsfs;
3495 
3496  /**
3497  * Array of pointers to hardware configurations supported by the codec,
3498  * or NULL if no hardware supported. The array is terminated by a NULL
3499  * pointer.
3500  *
3501  * The user can only access this field via avcodec_get_hw_config().
3502  */
3504 } AVCodec;
3505 
3506 #if FF_API_CODEC_GET_SET
3508 int av_codec_get_max_lowres(const AVCodec *codec);
3509 #endif
3510 
3511 struct MpegEncContext;
3512 
3513 /**
3514  * Retrieve supported hardware configurations for a codec.
3515  *
3516  * Values of index from zero to some maximum return the indexed configuration
3517  * descriptor; all other values return NULL. If the codec does not support
3518  * any hardware configurations then it will always return NULL.
3519  */
3520 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3521 
3522 /**
3523  * @defgroup lavc_hwaccel AVHWAccel
3524  *
3525  * @note Nothing in this structure should be accessed by the user. At some
3526  * point in future it will not be externally visible at all.
3527  *
3528  * @{
3529  */
3530 typedef struct AVHWAccel {
3531  /**
3532  * Name of the hardware accelerated codec.
3533  * The name is globally unique among encoders and among decoders (but an
3534  * encoder and a decoder can share the same name).
3535  */
3536  const char *name;
3537 
3538  /**
3539  * Type of codec implemented by the hardware accelerator.
3540  *
3541  * See AVMEDIA_TYPE_xxx
3542  */
3544 
3545  /**
3546  * Codec implemented by the hardware accelerator.
3547  *
3548  * See AV_CODEC_ID_xxx
3549  */
3551 
3552  /**
3553  * Supported pixel format.
3554  *
3555  * Only hardware accelerated formats are supported here.
3556  */
3558 
3559  /**
3560  * Hardware accelerated codec capabilities.
3561  * see AV_HWACCEL_CODEC_CAP_*
3562  */
3564 
3565  /*****************************************************************
3566  * No fields below this line are part of the public API. They
3567  * may not be used outside of libavcodec and can be changed and
3568  * removed at will.
3569  * New public fields should be added right above.
3570  *****************************************************************
3571  */
3572 
3573  /**
3574  * Allocate a custom buffer
3575  */
3577 
3578  /**
3579  * Called at the beginning of each frame or field picture.
3580  *
3581  * Meaningful frame information (codec specific) is guaranteed to
3582  * be parsed at this point. This function is mandatory.
3583  *
3584  * Note that buf can be NULL along with buf_size set to 0.
3585  * Otherwise, this means the whole frame is available at this point.
3586  *
3587  * @param avctx the codec context
3588  * @param buf the frame data buffer base
3589  * @param buf_size the size of the frame in bytes
3590  * @return zero if successful, a negative value otherwise
3591  */
3592  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3593 
3594  /**
3595  * Callback for parameter data (SPS/PPS/VPS etc).
3596  *
3597  * Useful for hardware decoders which keep persistent state about the
3598  * video parameters, and need to receive any changes to update that state.
3599  *
3600  * @param avctx the codec context
3601  * @param type the nal unit type
3602  * @param buf the nal unit data buffer
3603  * @param buf_size the size of the nal unit in bytes
3604  * @return zero if successful, a negative value otherwise
3605  */
3606  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3607 
3608  /**
3609  * Callback for each slice.
3610  *
3611  * Meaningful slice information (codec specific) is guaranteed to
3612  * be parsed at this point. This function is mandatory.
3613  * The only exception is XvMC, that works on MB level.
3614  *
3615  * @param avctx the codec context
3616  * @param buf the slice data buffer base
3617  * @param buf_size the size of the slice in bytes
3618  * @return zero if successful, a negative value otherwise
3619  */
3620  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3621 
3622  /**
3623  * Called at the end of each frame or field picture.
3624  *
3625  * The whole picture is parsed at this point and can now be sent
3626  * to the hardware accelerator. This function is mandatory.
3627  *
3628  * @param avctx the codec context
3629  * @return zero if successful, a negative value otherwise
3630  */
3632 
3633  /**
3634  * Size of per-frame hardware accelerator private data.
3635  *
3636  * Private data is allocated with av_mallocz() before
3637  * AVCodecContext.get_buffer() and deallocated after
3638  * AVCodecContext.release_buffer().
3639  */
3641 
3642  /**
3643  * Called for every Macroblock in a slice.
3644  *
3645  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3646  * Instead of decoding to raw picture, MB parameters are
3647  * stored in an array provided by the video driver.
3648  *
3649  * @param s the mpeg context
3650  */
3652 
3653  /**
3654  * Initialize the hwaccel private data.
3655  *
3656  * This will be called from ff_get_format(), after hwaccel and
3657  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3658  * is allocated.
3659  */
3661 
3662  /**
3663  * Uninitialize the hwaccel private data.
3664  *
3665  * This will be called from get_format() or avcodec_close(), after hwaccel
3666  * and hwaccel_context are already uninitialized.
3667  */
3669 
3670  /**
3671  * Size of the private data to allocate in
3672  * AVCodecInternal.hwaccel_priv_data.
3673  */
3675 
3676  /**
3677  * Internal hwaccel capabilities.
3678  */
3680 
3681  /**
3682  * Fill the given hw_frames context with current codec parameters. Called
3683  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3684  * details.
3685  *
3686  * This CAN be called before AVHWAccel.init is called, and you must assume
3687  * that avctx->hwaccel_priv_data is invalid.
3688  */
3690 } AVHWAccel;
3691 
3692 /**
3693  * HWAccel is experimental and is thus avoided in favor of non experimental
3694  * codecs
3695  */
3696 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3697 
3698 /**
3699  * Hardware acceleration should be used for decoding even if the codec level
3700  * used is unknown or higher than the maximum supported level reported by the
3701  * hardware driver.
3702  *
3703  * It's generally a good idea to pass this flag unless you have a specific
3704  * reason not to, as hardware tends to under-report supported levels.
3705  */
3706 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3707 
3708 /**
3709  * Hardware acceleration can output YUV pixel formats with a different chroma
3710  * sampling than 4:2:0 and/or other than 8 bits per component.
3711  */
3712 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3713 
3714 /**
3715  * Hardware acceleration should still be attempted for decoding when the
3716  * codec profile does not match the reported capabilities of the hardware.
3717  *
3718  * For example, this can be used to try to decode baseline profile H.264
3719  * streams in hardware - it will often succeed, because many streams marked
3720  * as baseline profile actually conform to constrained baseline profile.
3721  *
3722  * @warning If the stream is actually not supported then the behaviour is
3723  * undefined, and may include returning entirely incorrect output
3724  * while indicating success.
3725  */
3726 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3727 
3728 /**
3729  * @}
3730  */
3731 
3732 #if FF_API_AVPICTURE
3733 /**
3734  * @defgroup lavc_picture AVPicture
3735  *
3736  * Functions for working with AVPicture
3737  * @{
3738  */
3739 
3740 /**
3741  * Picture data structure.
3742  *
3743  * Up to four components can be stored into it, the last component is
3744  * alpha.
3745  * @deprecated use AVFrame or imgutils functions instead
3746  */
3747 typedef struct AVPicture {
3749  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3751  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3752 } AVPicture;
3753 
3754 /**
3755  * @}
3756  */
3757 #endif
3758 
3761 
3762  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3763 
3764  /**
3765  * Plain text, the text field must be set by the decoder and is
3766  * authoritative. ass and pict fields may contain approximations.
3767  */
3769 
3770  /**
3771  * Formatted text, the ass field must be set by the decoder and is
3772  * authoritative. pict and text fields may contain approximations.
3773  */
3775 };
3776 
3777 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3778 
3779 typedef struct AVSubtitleRect {
3780  int x; ///< top left corner of pict, undefined when pict is not set
3781  int y; ///< top left corner of pict, undefined when pict is not set
3782  int w; ///< width of pict, undefined when pict is not set
3783  int h; ///< height of pict, undefined when pict is not set
3784  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3785 
3786 #if FF_API_AVPICTURE
3787  /**
3788  * @deprecated unused
3789  */
3792 #endif
3793  /**
3794  * data+linesize for the bitmap of this subtitle.
3795  * Can be set for text/ass as well once they are rendered.
3796  */
3798  int linesize[4];
3799 
3801 
3802  char *text; ///< 0 terminated plain UTF-8 text
3803 
3804  /**
3805  * 0 terminated ASS/SSA compatible event line.
3806  * The presentation of this is unaffected by the other values in this
3807  * struct.
3808  */
3809  char *ass;
3810 
3811  int flags;
3812 } AVSubtitleRect;
3813 
3814 typedef struct AVSubtitle {
3815  uint16_t format; /* 0 = graphics */
3816  uint32_t start_display_time; /* relative to packet pts, in ms */
3817  uint32_t end_display_time; /* relative to packet pts, in ms */
3818  unsigned num_rects;
3820  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3821 } AVSubtitle;
3822 
3823 /**
3824  * This struct describes the properties of an encoded stream.
3825  *
3826  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3827  * be allocated with avcodec_parameters_alloc() and freed with
3828  * avcodec_parameters_free().
3829  */
3830 typedef struct AVCodecParameters {
3831  /**
3832  * General type of the encoded data.
3833  */
3835  /**
3836  * Specific type of the encoded data (the codec used).
3837  */
3839  /**
3840  * Additional information about the codec (corresponds to the AVI FOURCC).
3841  */
3842  uint32_t codec_tag;
3843 
3844  /**
3845  * Extra binary data needed for initializing the decoder, codec-dependent.
3846  *
3847  * Must be allocated with av_malloc() and will be freed by
3848  * avcodec_parameters_free(). The allocated size of extradata must be at
3849  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3850  * bytes zeroed.
3851  */
3853  /**
3854  * Size of the extradata content in bytes.
3855  */
3857 
3858  /**
3859  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3860  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3861  */
3862  int format;
3863 
3864  /**
3865  * The average bitrate of the encoded data (in bits per second).
3866  */
3867  int64_t bit_rate;
3868 
3869  /**
3870  * The number of bits per sample in the codedwords.
3871  *
3872  * This is basically the bitrate per sample. It is mandatory for a bunch of
3873  * formats to actually decode them. It's the number of bits for one sample in
3874  * the actual coded bitstream.
3875  *
3876  * This could be for example 4 for ADPCM
3877  * For PCM formats this matches bits_per_raw_sample
3878  * Can be 0
3879  */
3881 
3882  /**
3883  * This is the number of valid bits in each output sample. If the
3884  * sample format has more bits, the least significant bits are additional
3885  * padding bits, which are always 0. Use right shifts to reduce the sample
3886  * to its actual size. For example, audio formats with 24 bit samples will
3887  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3888  * To get the original sample use "(int32_t)sample >> 8"."
3889  *
3890  * For ADPCM this might be 12 or 16 or similar
3891  * Can be 0
3892  */
3894 
3895  /**
3896  * Codec-specific bitstream restrictions that the stream conforms to.
3897  */
3898  int profile;
3899  int level;
3900 
3901  /**
3902  * Video only. The dimensions of the video frame in pixels.
3903  */
3904  int width;
3905  int height;
3906 
3907  /**
3908  * Video only. The aspect ratio (width / height) which a single pixel
3909  * should have when displayed.
3910  *
3911  * When the aspect ratio is unknown / undefined, the numerator should be
3912  * set to 0 (the denominator may have any value).
3913  */
3915 
3916  /**
3917  * Video only. The order of the fields in interlaced video.
3918  */
3920 
3921  /**
3922  * Video only. Additional colorspace characteristics.
3923  */
3929 
3930  /**
3931  * Video only. Number of delayed frames.
3932  */
3934 
3935  /**
3936  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3937  * unknown or unspecified, otherwise the number of bits set must be equal to
3938  * the channels field.
3939  */
3940  uint64_t channel_layout;
3941  /**
3942  * Audio only. The number of audio channels.
3943  */
3945  /**
3946  * Audio only. The number of audio samples per second.
3947  */
3949  /**
3950  * Audio only. The number of bytes per coded audio frame, required by some
3951  * formats.
3952  *
3953  * Corresponds to nBlockAlign in WAVEFORMATEX.
3954  */
3956  /**
3957  * Audio only. Audio frame size, if known. Required by some formats to be static.
3958  */
3960 
3961  /**
3962  * Audio only. The amount of padding (in samples) inserted by the encoder at
3963  * the beginning of the audio. I.e. this number of leading decoded samples
3964  * must be discarded by the caller to get the original audio without leading
3965  * padding.
3966  */
3968  /**
3969  * Audio only. The amount of padding (in samples) appended by the encoder to
3970  * the end of the audio. I.e. this number of decoded samples must be
3971  * discarded by the caller from the end of the stream to get the original
3972  * audio without any trailing padding.
3973  */
3975  /**
3976  * Audio only. Number of samples to skip after a discontinuity.
3977  */
3980 
3981 /**
3982  * If c is NULL, returns the first registered codec,
3983  * if c is non-NULL, returns the next registered codec after c,
3984  * or NULL if c is the last one.
3985  */
3986 AVCodec *av_codec_next(const AVCodec *c);
3987 
3988 /**
3989  * Return the LIBAVCODEC_VERSION_INT constant.
3990  */
3991 unsigned avcodec_version(void);
3992 
3993 /**
3994  * Return the libavcodec build-time configuration.
3995  */
3996 const char *avcodec_configuration(void);
3997 
3998 /**
3999  * Return the libavcodec license.
4000  */
4001 const char *avcodec_license(void);
4002 
4003 /**
4004  * Register the codec codec and initialize libavcodec.
4005  *
4006  * @warning either this function or avcodec_register_all() must be called
4007  * before any other libavcodec functions.
4008  *
4009  * @see avcodec_register_all()
4010  */
4011 void avcodec_register(AVCodec *codec);
4012 
4013 /**
4014  * Register all the codecs, parsers and bitstream filters which were enabled at
4015  * configuration time. If you do not call this function you can select exactly
4016  * which formats you want to support, by using the individual registration
4017  * functions.
4018  *
4019  * @see avcodec_register
4020  * @see av_register_codec_parser
4021  * @see av_register_bitstream_filter
4022  */
4023 void avcodec_register_all(void);
4024 
4025 /**
4026  * Allocate an AVCodecContext and set its fields to default values. The
4027  * resulting struct should be freed with avcodec_free_context().
4028  *
4029  * @param codec if non-NULL, allocate private data and initialize defaults
4030  * for the given codec. It is illegal to then call avcodec_open2()
4031  * with a different codec.
4032  * If NULL, then the codec-specific defaults won't be initialized,
4033  * which may result in suboptimal default settings (this is
4034  * important mainly for encoders, e.g. libx264).
4035  *
4036  * @return An AVCodecContext filled with default values or NULL on failure.
4037  */
4039 
4040 /**
4041  * Free the codec context and everything associated with it and write NULL to
4042  * the provided pointer.
4043  */
4044 void avcodec_free_context(AVCodecContext **avctx);
4045 
4046 #if FF_API_GET_CONTEXT_DEFAULTS
4047 /**
4048  * @deprecated This function should not be used, as closing and opening a codec
4049  * context multiple time is not supported. A new codec context should be
4050  * allocated for each new use.
4051  */
4053 #endif
4054 
4055 /**
4056  * Get the AVClass for AVCodecContext. It can be used in combination with
4057  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4058  *
4059  * @see av_opt_find().
4060  */
4061 const AVClass *avcodec_get_class(void);
4062 
4063 #if FF_API_COPY_CONTEXT
4064 /**
4065  * Get the AVClass for AVFrame. It can be used in combination with
4066  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4067  *
4068  * @see av_opt_find().
4069  */
4070 const AVClass *avcodec_get_frame_class(void);
4071 
4072 /**
4073  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4074  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4075  *
4076  * @see av_opt_find().
4077  */
4079 
4080 /**
4081  * Copy the settings of the source AVCodecContext into the destination
4082  * AVCodecContext. The resulting destination codec context will be
4083  * unopened, i.e. you are required to call avcodec_open2() before you
4084  * can use this AVCodecContext to decode/encode video/audio data.
4085  *
4086  * @param dest target codec context, should be initialized with
4087  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4088  * @param src source codec context
4089  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4090  *
4091  * @deprecated The semantics of this function are ill-defined and it should not
4092  * be used. If you need to transfer the stream parameters from one codec context
4093  * to another, use an intermediate AVCodecParameters instance and the
4094  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4095  * functions.
4096  */
4099 #endif
4100 
4101 /**
4102  * Allocate a new AVCodecParameters and set its fields to default values
4103  * (unknown/invalid/0). The returned struct must be freed with
4104  * avcodec_parameters_free().
4105  */
4107 
4108 /**
4109  * Free an AVCodecParameters instance and everything associated with it and
4110  * write NULL to the supplied pointer.
4111  */
4113 
4114 /**
4115  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4116  * replaced with newly allocated duplicates of the corresponding fields in src.
4117  *
4118  * @return >= 0 on success, a negative AVERROR code on failure.
4119  */
4121 
4122 /**
4123  * Fill the parameters struct based on the values from the supplied codec
4124  * context. Any allocated fields in par are freed and replaced with duplicates
4125  * of the corresponding fields in codec.
4126  *
4127  * @return >= 0 on success, a negative AVERROR code on failure
4128  */
4130  const AVCodecContext *codec);
4131 
4132 /**
4133  * Fill the codec context based on the values from the supplied codec
4134  * parameters. Any allocated fields in codec that have a corresponding field in
4135  * par are freed and replaced with duplicates of the corresponding field in par.
4136  * Fields in codec that do not have a counterpart in par are not touched.
4137  *
4138  * @return >= 0 on success, a negative AVERROR code on failure.
4139  */
4141  const AVCodecParameters *par);
4142 
4143 /**
4144  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4145  * function the context has to be allocated with avcodec_alloc_context3().
4146  *
4147  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4148  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4149  * retrieving a codec.
4150  *
4151  * @warning This function is not thread safe!
4152  *
4153  * @note Always call this function before using decoding routines (such as
4154  * @ref avcodec_receive_frame()).
4155  *
4156  * @code
4157  * avcodec_register_all();
4158  * av_dict_set(&opts, "b", "2.5M", 0);
4159  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4160  * if (!codec)
4161  * exit(1);
4162  *
4163  * context = avcodec_alloc_context3(codec);
4164  *
4165  * if (avcodec_open2(context, codec, opts) < 0)
4166  * exit(1);
4167  * @endcode
4168  *
4169  * @param avctx The context to initialize.
4170  * @param codec The codec to open this context for. If a non-NULL codec has been
4171  * previously passed to avcodec_alloc_context3() or
4172  * for this context, then this parameter MUST be either NULL or
4173  * equal to the previously passed codec.
4174  * @param options A dictionary filled with AVCodecContext and codec-private options.
4175  * On return this object will be filled with options that were not found.
4176  *
4177  * @return zero on success, a negative value on error
4178  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4179  * av_dict_set(), av_opt_find().
4180  */
4181 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4182 
4183 /**
4184  * Close a given AVCodecContext and free all the data associated with it
4185  * (but not the AVCodecContext itself).
4186  *
4187  * Calling this function on an AVCodecContext that hasn't been opened will free
4188  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4189  * codec. Subsequent calls will do nothing.
4190  *
4191  * @note Do not use this function. Use avcodec_free_context() to destroy a
4192  * codec context (either open or closed). Opening and closing a codec context
4193  * multiple times is not supported anymore -- use multiple codec contexts
4194  * instead.
4195  */
4196 int avcodec_close(AVCodecContext *avctx);
4197 
4198 /**
4199  * Free all allocated data in the given subtitle struct.
4200  *
4201  * @param sub AVSubtitle to free.
4202  */
4203 void avsubtitle_free(AVSubtitle *sub);
4204 
4205 /**
4206  * @}
4207  */
4208 
4209 /**
4210  * @addtogroup lavc_packet
4211  * @{
4212  */
4213 
4214 /**
4215  * Allocate an AVPacket and set its fields to default values. The resulting
4216  * struct must be freed using av_packet_free().
4217  *
4218  * @return An AVPacket filled with default values or NULL on failure.
4219  *
4220  * @note this only allocates the AVPacket itself, not the data buffers. Those
4221  * must be allocated through other means such as av_new_packet.
4222  *
4223  * @see av_new_packet
4224  */
4225 AVPacket *av_packet_alloc(void);
4226 
4227 /**
4228  * Create a new packet that references the same data as src.
4229  *
4230  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4231  *
4232  * @return newly created AVPacket on success, NULL on error.
4233  *
4234  * @see av_packet_alloc
4235  * @see av_packet_ref
4236  */
4238 
4239 /**
4240  * Free the packet, if the packet is reference counted, it will be
4241  * unreferenced first.
4242  *
4243  * @param pkt packet to be freed. The pointer will be set to NULL.
4244  * @note passing NULL is a no-op.
4245  */
4246 void av_packet_free(AVPacket **pkt);
4247 
4248 /**
4249  * Initialize optional fields of a packet with default values.
4250  *
4251  * Note, this does not touch the data and size members, which have to be
4252  * initialized separately.
4253  *
4254  * @param pkt packet
4255  */
4256 void av_init_packet(AVPacket *pkt);
4257 
4258 /**
4259  * Allocate the payload of a packet and initialize its fields with
4260  * default values.
4261  *
4262  * @param pkt packet
4263  * @param size wanted payload size
4264  * @return 0 if OK, AVERROR_xxx otherwise
4265  */
4266 int av_new_packet(AVPacket *pkt, int size);
4267 
4268 /**
4269  * Reduce packet size, correctly zeroing padding
4270  *
4271  * @param pkt packet
4272  * @param size new size
4273  */
4274 void av_shrink_packet(AVPacket *pkt, int size);
4275 
4276 /**
4277  * Increase packet size, correctly zeroing padding
4278  *
4279  * @param pkt packet
4280  * @param grow_by number of bytes by which to increase the size of the packet
4281  */
4282 int av_grow_packet(AVPacket *pkt, int grow_by);
4283 
4284 /**
4285  * Initialize a reference-counted packet from av_malloc()ed data.
4286  *
4287  * @param pkt packet to be initialized. This function will set the data, size,
4288  * buf and destruct fields, all others are left untouched.
4289  * @param data Data allocated by av_malloc() to be used as packet data. If this
4290  * function returns successfully, the data is owned by the underlying AVBuffer.
4291  * The caller may not access the data through other means.
4292  * @param size size of data in bytes, without the padding. I.e. the full buffer
4293  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4294  *
4295  * @return 0 on success, a negative AVERROR on error
4296  */
4298 
4299 #if FF_API_AVPACKET_OLD_API
4300 /**
4301  * @warning This is a hack - the packet memory allocation stuff is broken. The
4302  * packet is allocated if it was not really allocated.
4303  *
4304  * @deprecated Use av_packet_ref
4305  */
4307 int av_dup_packet(AVPacket *pkt);
4308 /**
4309  * Copy packet, including contents
4310  *
4311  * @return 0 on success, negative AVERROR on fail
4312  *
4313  * @deprecated Use av_packet_ref
4314  */
4316 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4317 
4318 /**
4319  * Copy packet side data
4320  *
4321  * @return 0 on success, negative AVERROR on fail
4322  *
4323  * @deprecated Use av_packet_copy_props
4324  */
4326 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4327 
4328 /**
4329  * Free a packet.
4330  *
4331  * @deprecated Use av_packet_unref
4332  *
4333  * @param pkt packet to free
4334  */
4336 void av_free_packet(AVPacket *pkt);
4337 #endif
4338 /**
4339  * Allocate new information of a packet.
4340  *
4341  * @param pkt packet
4342  * @param type side information type
4343  * @param size side information size
4344  * @return pointer to fresh allocated data or NULL otherwise
4345  */
4347  int size);
4348 
4349 /**
4350  * Wrap an existing array as a packet side data.
4351  *
4352  * @param pkt packet
4353  * @param type side information type
4354  * @param data the side data array. It must be allocated with the av_malloc()
4355  * family of functions. The ownership of the data is transferred to
4356  * pkt.
4357  * @param size side information size
4358  * @return a non-negative number on success, a negative AVERROR code on
4359  * failure. On failure, the packet is unchanged and the data remains
4360  * owned by the caller.
4361  */
4363  uint8_t *data, size_t size);
4364 
4365 /**
4366  * Shrink the already allocated side data buffer
4367  *
4368  * @param pkt packet
4369  * @param type side information type
4370  * @param size new side information size
4371  * @return 0 on success, < 0 on failure
4372  */
4374  int size);
4375 
4376 /**
4377  * Get side information from packet.
4378  *
4379  * @param pkt packet
4380  * @param type desired side information type
4381  * @param size pointer for side information size to store (optional)
4382  * @return pointer to data if present or NULL otherwise
4383  */
4385  int *size);
4386 
4387 #if FF_API_MERGE_SD_API
4390 
4393 #endif
4394 
4396 
4397 /**
4398  * Pack a dictionary for use in side_data.
4399  *
4400  * @param dict The dictionary to pack.
4401  * @param size pointer to store the size of the returned data
4402  * @return pointer to data if successful, NULL otherwise
4403  */
4405 /**
4406  * Unpack a dictionary from side_data.
4407  *
4408  * @param data data from side_data
4409  * @param size size of the data
4410  * @param dict the metadata storage dictionary
4411  * @return 0 on success, < 0 on failure
4412  */
4413 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4414 
4415 
4416 /**
4417  * Convenience function to free all the side data stored.
4418  * All the other fields stay untouched.
4419  *
4420  * @param pkt packet
4421  */
4423 
4424 /**
4425  * Setup a new reference to the data described by a given packet
4426  *
4427  * If src is reference-counted, setup dst as a new reference to the
4428  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4429  * data from src into it.
4430  *
4431  * All the other fields are copied from src.
4432  *
4433  * @see av_packet_unref
4434  *
4435  * @param dst Destination packet
4436  * @param src Source packet
4437  *
4438  * @return 0 on success, a negative AVERROR on error.
4439  */
4440 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4441 
4442 /**
4443  * Wipe the packet.
4444  *
4445  * Unreference the buffer referenced by the packet and reset the
4446  * remaining packet fields to their default values.
4447  *
4448  * @param pkt The packet to be unreferenced.
4449  */
4451 
4452 /**
4453  * Move every field in src to dst and reset src.
4454  *
4455  * @see av_packet_unref
4456  *
4457  * @param src Source packet, will be reset
4458  * @param dst Destination packet
4459  */
4461 
4462 /**
4463  * Copy only "properties" fields from src to dst.
4464  *
4465  * Properties for the purpose of this function are all the fields
4466  * beside those related to the packet data (buf, data, size)
4467  *
4468  * @param dst Destination packet
4469  * @param src Source packet
4470  *
4471  * @return 0 on success AVERROR on failure.
4472  */
4473 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4474 
4475 /**
4476  * Convert valid timing fields (timestamps / durations) in a packet from one
4477  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4478  * ignored.
4479  *
4480  * @param pkt packet on which the conversion will be performed
4481  * @param tb_src source timebase, in which the timing fields in pkt are
4482  * expressed
4483  * @param tb_dst destination timebase, to which the timing fields will be
4484  * converted
4485  */
4486 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4487 
4488 /**
4489  * @}
4490  */
4491 
4492 /**
4493  * @addtogroup lavc_decoding
4494  * @{
4495  */
4496 
4497 /**
4498  * Find a registered decoder with a matching codec ID.
4499  *
4500  * @param id AVCodecID of the requested decoder
4501  * @return A decoder if one was found, NULL otherwise.
4502  */
4504 
4505 /**
4506  * Find a registered decoder with the specified name.
4507  *
4508  * @param name name of the requested decoder
4509  * @return A decoder if one was found, NULL otherwise.
4510  */
4512 
4513 /**
4514  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4515  * it can be called by custom get_buffer2() implementations for decoders without
4516  * AV_CODEC_CAP_DR1 set.
4517  */
4519 
4520 /**
4521  * Modify width and height values so that they will result in a memory
4522  * buffer that is acceptable for the codec if you do not use any horizontal
4523  * padding.
4524  *
4525  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4526  */
4528 
4529 /**
4530  * Modify width and height values so that they will result in a memory
4531  * buffer that is acceptable for the codec if you also ensure that all
4532  * line sizes are a multiple of the respective linesize_align[i].
4533  *
4534  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4535  */
4537  int linesize_align[AV_NUM_DATA_POINTERS]);
4538 
4539 /**
4540  * Converts AVChromaLocation to swscale x/y chroma position.
4541  *
4542  * The positions represent the chroma (0,0) position in a coordinates system
4543  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4544  *
4545  * @param xpos horizontal chroma sample position
4546  * @param ypos vertical chroma sample position
4547  */
4548 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4549 
4550 /**
4551  * Converts swscale x/y chroma position to AVChromaLocation.
4552  *
4553  * The positions represent the chroma (0,0) position in a coordinates system
4554  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4555  *
4556  * @param xpos horizontal chroma sample position
4557  * @param ypos vertical chroma sample position
4558  */
4559 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4560 
4561 /**
4562  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4563  *
4564  * Some decoders may support multiple frames in a single AVPacket. Such
4565  * decoders would then just decode the first frame and the return value would be
4566  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4567  * called again with an AVPacket containing the remaining data in order to
4568  * decode the second frame, etc... Even if no frames are returned, the packet
4569  * needs to be fed to the decoder with remaining data until it is completely
4570  * consumed or an error occurs.
4571  *
4572  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4573  * and output. This means that for some packets they will not immediately
4574  * produce decoded output and need to be flushed at the end of decoding to get
4575  * all the decoded data. Flushing is done by calling this function with packets
4576  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4577  * returning samples. It is safe to flush even those decoders that are not
4578  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4579  *
4580  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4581  * larger than the actual read bytes because some optimized bitstream
4582  * readers read 32 or 64 bits at once and could read over the end.
4583  *
4584  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4585  * before packets may be fed to the decoder.
4586  *
4587  * @param avctx the codec context
4588  * @param[out] frame The AVFrame in which to store decoded audio samples.
4589  * The decoder will allocate a buffer for the decoded frame by
4590  * calling the AVCodecContext.get_buffer2() callback.
4591  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4592  * reference counted and the returned reference belongs to the
4593  * caller. The caller must release the frame using av_frame_unref()
4594  * when the frame is no longer needed. The caller may safely write
4595  * to the frame if av_frame_is_writable() returns 1.
4596  * When AVCodecContext.refcounted_frames is set to 0, the returned
4597  * reference belongs to the decoder and is valid only until the
4598  * next call to this function or until closing or flushing the
4599  * decoder. The caller may not write to it.
4600  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4601  * non-zero. Note that this field being set to zero
4602  * does not mean that an error has occurred. For
4603  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4604  * call is guaranteed to produce a frame.
4605  * @param[in] avpkt The input AVPacket containing the input buffer.
4606  * At least avpkt->data and avpkt->size should be set. Some
4607  * decoders might also require additional fields to be set.
4608  * @return A negative error code is returned if an error occurred during
4609  * decoding, otherwise the number of bytes consumed from the input
4610  * AVPacket is returned.
4611  *
4612 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4613  */
4616  int *got_frame_ptr, const AVPacket *avpkt);
4617 
4618 /**
4619  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4620  * Some decoders may support multiple frames in a single AVPacket, such
4621  * decoders would then just decode the first frame.
4622  *
4623  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4624  * the actual read bytes because some optimized bitstream readers read 32 or 64
4625  * bits at once and could read over the end.
4626  *
4627  * @warning The end of the input buffer buf should be set to 0 to ensure that
4628  * no overreading happens for damaged MPEG streams.
4629  *
4630  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4631  * between input and output, these need to be fed with avpkt->data=NULL,
4632  * avpkt->size=0 at the end to return the remaining frames.
4633  *
4634  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4635  * before packets may be fed to the decoder.
4636  *
4637  * @param avctx the codec context
4638  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4639  * Use av_frame_alloc() to get an AVFrame. The codec will
4640  * allocate memory for the actual bitmap by calling the
4641  * AVCodecContext.get_buffer2() callback.
4642  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4643  * reference counted and the returned reference belongs to the
4644  * caller. The caller must release the frame using av_frame_unref()
4645  * when the frame is no longer needed. The caller may safely write
4646  * to the frame if av_frame_is_writable() returns 1.
4647  * When AVCodecContext.refcounted_frames is set to 0, the returned
4648  * reference belongs to the decoder and is valid only until the
4649  * next call to this function or until closing or flushing the
4650  * decoder. The caller may not write to it.
4651  *
4652  * @param[in] avpkt The input AVPacket containing the input buffer.
4653  * You can create such packet with av_init_packet() and by then setting
4654  * data and size, some decoders might in addition need other fields like
4655  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4656  * fields possible.
4657  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4658  * @return On error a negative value is returned, otherwise the number of bytes
4659  * used or zero if no frame could be decompressed.
4660  *
4661  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4662  */
4664 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4665  int *got_picture_ptr,
4666  const AVPacket *avpkt);
4667 
4668 /**
4669  * Decode a subtitle message.
4670  * Return a negative value on error, otherwise return the number of bytes used.
4671  * If no subtitle could be decompressed, got_sub_ptr is zero.
4672  * Otherwise, the subtitle is stored in *sub.
4673  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4674  * simplicity, because the performance difference is expect to be negligible
4675  * and reusing a get_buffer written for video codecs would probably perform badly
4676  * due to a potentially very different allocation pattern.
4677  *
4678  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4679  * and output. This means that for some packets they will not immediately
4680  * produce decoded output and need to be flushed at the end of decoding to get
4681  * all the decoded data. Flushing is done by calling this function with packets
4682  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4683  * returning subtitles. It is safe to flush even those decoders that are not
4684  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4685  *
4686  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4687  * before packets may be fed to the decoder.
4688  *
4689  * @param avctx the codec context
4690  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4691  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4692  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4693  * @param[in] avpkt The input AVPacket containing the input buffer.
4694  */
4696  int *got_sub_ptr,
4697  AVPacket *avpkt);
4698 
4699 /**
4700  * Supply raw packet data as input to a decoder.
4701  *
4702  * Internally, this call will copy relevant AVCodecContext fields, which can
4703  * influence decoding per-packet, and apply them when the packet is actually
4704  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4705  * decoder to drop the frame contained by the packet sent with this function.)
4706  *
4707  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4708  * larger than the actual read bytes because some optimized bitstream
4709  * readers read 32 or 64 bits at once and could read over the end.
4710  *
4711  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4712  * on the same AVCodecContext. It will return unexpected results now
4713  * or in future libavcodec versions.
4714  *
4715  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4716  * before packets may be fed to the decoder.
4717  *
4718  * @param avctx codec context
4719  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4720  * frame, or several complete audio frames.
4721  * Ownership of the packet remains with the caller, and the
4722  * decoder will not write to the packet. The decoder may create
4723  * a reference to the packet data (or copy it if the packet is
4724  * not reference-counted).
4725  * Unlike with older APIs, the packet is always fully consumed,
4726  * and if it contains multiple frames (e.g. some audio codecs),
4727  * will require you to call avcodec_receive_frame() multiple
4728  * times afterwards before you can send a new packet.
4729  * It can be NULL (or an AVPacket with data set to NULL and
4730  * size set to 0); in this case, it is considered a flush
4731  * packet, which signals the end of the stream. Sending the
4732  * first flush packet will return success. Subsequent ones are
4733  * unnecessary and will return AVERROR_EOF. If the decoder
4734  * still has frames buffered, it will return them after sending
4735  * a flush packet.
4736  *
4737  * @return 0 on success, otherwise negative error code:
4738  * AVERROR(EAGAIN): input is not accepted in the current state - user
4739  * must read output with avcodec_receive_frame() (once
4740  * all output is read, the packet should be resent, and
4741  * the call will not fail with EAGAIN).
4742  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4743  * be sent to it (also returned if more than 1 flush
4744  * packet is sent)
4745  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4746  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4747  * other errors: legitimate decoding errors
4748  */
4749 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4750 
4751 /**
4752  * Return decoded output data from a decoder.
4753  *
4754  * @param avctx codec context
4755  * @param frame This will be set to a reference-counted video or audio
4756  * frame (depending on the decoder type) allocated by the
4757  * decoder. Note that the function will always call
4758  * av_frame_unref(frame) before doing anything else.
4759  *
4760  * @return
4761  * 0: success, a frame was returned
4762  * AVERROR(EAGAIN): output is not available in this state - user must try
4763  * to send new input
4764  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4765  * no more output frames
4766  * AVERROR(EINVAL): codec not opened, or it is an encoder
4767  * other negative values: legitimate decoding errors
4768  */
4770 
4771 /**
4772  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4773  * to retrieve buffered output packets.
4774  *
4775  * @param avctx codec context
4776  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4777  * Ownership of the frame remains with the caller, and the
4778  * encoder will not write to the frame. The encoder may create
4779  * a reference to the frame data (or copy it if the frame is
4780  * not reference-counted).
4781  * It can be NULL, in which case it is considered a flush
4782  * packet. This signals the end of the stream. If the encoder
4783  * still has packets buffered, it will return them after this
4784  * call. Once flushing mode has been entered, additional flush
4785  * packets are ignored, and sending frames will return
4786  * AVERROR_EOF.
4787  *
4788  * For audio:
4789  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4790  * can have any number of samples.
4791  * If it is not set, frame->nb_samples must be equal to
4792  * avctx->frame_size for all frames except the last.
4793  * The final frame may be smaller than avctx->frame_size.
4794  * @return 0 on success, otherwise negative error code:
4795  * AVERROR(EAGAIN): input is not accepted in the current state - user
4796  * must read output with avcodec_receive_packet() (once
4797  * all output is read, the packet should be resent, and
4798  * the call will not fail with EAGAIN).
4799  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4800  * be sent to it
4801  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4802  * decoder, or requires flush
4803  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4804  * other errors: legitimate decoding errors
4805  */
4806 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4807 
4808 /**
4809  * Read encoded data from the encoder.
4810  *
4811  * @param avctx codec context
4812  * @param avpkt This will be set to a reference-counted packet allocated by the
4813  * encoder. Note that the function will always call
4814  * av_frame_unref(frame) before doing anything else.
4815  * @return 0 on success, otherwise negative error code:
4816  * AVERROR(EAGAIN): output is not available in the current state - user
4817  * must try to send input
4818  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4819  * no more output packets
4820  * AVERROR(EINVAL): codec not opened, or it is an encoder
4821  * other errors: legitimate decoding errors
4822  */
4823 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4824 
4825 /**
4826  * Create and return a AVHWFramesContext with values adequate for hardware
4827  * decoding. This is meant to get called from the get_format callback, and is
4828  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4829  * This API is for decoding with certain hardware acceleration modes/APIs only.
4830  *
4831  * The returned AVHWFramesContext is not initialized. The caller must do this
4832  * with av_hwframe_ctx_init().
4833  *
4834  * Calling this function is not a requirement, but makes it simpler to avoid
4835  * codec or hardware API specific details when manually allocating frames.
4836  *
4837  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
4838  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
4839  * it unnecessary to call this function or having to care about
4840  * AVHWFramesContext initialization at all.
4841  *
4842  * There are a number of requirements for calling this function:
4843  *
4844  * - It must be called from get_format with the same avctx parameter that was
4845  * passed to get_format. Calling it outside of get_format is not allowed, and
4846  * can trigger undefined behavior.
4847  * - The function is not always supported (see description of return values).
4848  * Even if this function returns successfully, hwaccel initialization could
4849  * fail later. (The degree to which implementations check whether the stream
4850  * is actually supported varies. Some do this check only after the user's
4851  * get_format callback returns.)
4852  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
4853  * user decides to use a AVHWFramesContext prepared with this API function,
4854  * the user must return the same hw_pix_fmt from get_format.
4855  * - The device_ref passed to this function must support the given hw_pix_fmt.
4856  * - After calling this API function, it is the user's responsibility to
4857  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
4858  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
4859  * before returning from get_format (this is implied by the normal
4860  * AVCodecContext.hw_frames_ctx API rules).
4861  * - The AVHWFramesContext parameters may change every time time get_format is
4862  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
4863  * you are inherently required to go through this process again on every
4864  * get_format call.
4865  * - It is perfectly possible to call this function without actually using
4866  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
4867  * previously initialized AVHWFramesContext, and calling this API function
4868  * only to test whether the required frame parameters have changed.
4869  * - Fields that use dynamically allocated values of any kind must not be set
4870  * by the user unless setting them is explicitly allowed by the documentation.
4871  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
4872  * the new free callback must call the potentially set previous free callback.
4873  * This API call may set any dynamically allocated fields, including the free
4874  * callback.
4875  *
4876  * The function will set at least the following fields on AVHWFramesContext
4877  * (potentially more, depending on hwaccel API):
4878  *
4879  * - All fields set by av_hwframe_ctx_alloc().
4880  * - Set the format field to hw_pix_fmt.
4881  * - Set the sw_format field to the most suited and most versatile format. (An
4882  * implication is that this will prefer generic formats over opaque formats
4883  * with arbitrary restrictions, if possible.)
4884  * - Set the width/height fields to the coded frame size, rounded up to the
4885  * API-specific minimum alignment.
4886  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
4887  * field to the number of maximum reference surfaces possible with the codec,
4888  * plus 1 surface for the user to work (meaning the user can safely reference
4889  * at most 1 decoded surface at a time), plus additional buffering introduced
4890  * by frame threading. If the hwaccel does not require pre-allocation, the
4891  * field is left to 0, and the decoder will allocate new surfaces on demand
4892  * during decoding.
4893  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
4894  * hardware API.
4895  *
4896  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
4897  * with basic frame parameters set.
4898  *
4899  * The function is stateless, and does not change the AVCodecContext or the
4900  * device_ref AVHWDeviceContext.
4901  *
4902  * @param avctx The context which is currently calling get_format, and which
4903  * implicitly contains all state needed for filling the returned
4904  * AVHWFramesContext properly.
4905  * @param device_ref A reference to the AVHWDeviceContext describing the device
4906  * which will be used by the hardware decoder.
4907  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
4908  * @param out_frames_ref On success, set to a reference to an _uninitialized_
4909  * AVHWFramesContext, created from the given device_ref.
4910  * Fields will be set to values required for decoding.
4911  * Not changed if an error is returned.
4912  * @return zero on success, a negative value on error. The following error codes
4913  * have special semantics:
4914  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
4915  * is always manual, or it is a decoder which does not
4916  * support setting AVCodecContext.hw_frames_ctx at all,
4917  * or it is a software format.
4918  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
4919  * this configuration, or the device_ref is not supported
4920  * for the hwaccel referenced by hw_pix_fmt.
4921  */
4923  AVBufferRef *device_ref,
4925  AVBufferRef **out_frames_ref);
4926 
4927 
4928 
4929 /**
4930  * @defgroup lavc_parsing Frame parsing
4931  * @{
4932  */
4933 
4936  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4937  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4938  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4939 };
4940 
4941 typedef struct AVCodecParserContext {
4942  void *priv_data;
4944  int64_t frame_offset; /* offset of the current frame */
4945  int64_t cur_offset; /* current offset
4946  (incremented by each av_parser_parse()) */
4947  int64_t next_frame_offset; /* offset of the next frame */
4948  /* video info */
4949  int pict_type; /* XXX: Put it back in AVCodecContext. */
4950  /**
4951  * This field is used for proper frame duration computation in lavf.
4952  * It signals, how much longer the frame duration of the current frame
4953  * is compared to normal frame duration.
4954  *
4955  * frame_duration = (1 + repeat_pict) * time_base
4956  *
4957  * It is used by codecs like H.264 to display telecined material.
4958  */
4959  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4960  int64_t pts; /* pts of the current frame */
4961  int64_t dts; /* dts of the current frame */
4962 
4963  /* private data */
4964  int64_t last_pts;
4965  int64_t last_dts;
4967 
4968 #define AV_PARSER_PTS_NB 4
4973 
4974  int flags;
4975 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4976 #define PARSER_FLAG_ONCE 0x0002
4977 /// Set if the parser has a valid file offset
4978 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4979 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4980 
4981  int64_t offset; ///< byte offset from starting packet start
4983 
4984  /**
4985  * Set by parser to 1 for key frames and 0 for non-key frames.
4986  * It is initialized to -1, so if the parser doesn't set this flag,
4987  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4988  * will be used.
4989  */
4991 
4992 #if FF_API_CONVERGENCE_DURATION
4993  /**
4994  * @deprecated unused
4995  */
4998 #endif
4999 
5000  // Timestamp generation support:
5001  /**
5002  * Synchronization point for start of timestamp generation.
5003  *
5004  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5005  * (default).
5006  *
5007  * For example, this corresponds to presence of H.264 buffering period
5008  * SEI message.
5009  */
5011 
5012  /**
5013  * Offset of the current timestamp against last timestamp sync point in
5014  * units of AVCodecContext.time_base.
5015  *
5016  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5017  * contain a valid timestamp offset.
5018  *
5019  * Note that the timestamp of sync point has usually a nonzero
5020  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5021  * the next frame after timestamp sync point will be usually 1.
5022  *
5023  * For example, this corresponds to H.264 cpb_removal_delay.
5024  */
5026 
5027  /**
5028  * Presentation delay of current frame in units of AVCodecContext.time_base.
5029  *
5030  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5031  * contain valid non-negative timestamp delta (presentation time of a frame
5032  * must not lie in the past).
5033  *
5034  * This delay represents the difference between decoding and presentation
5035  * time of the frame.
5036  *
5037  * For example, this corresponds to H.264 dpb_output_delay.
5038  */
5040 
5041  /**
5042  * Position of the packet in file.
5043  *
5044  * Analogous to cur_frame_pts/dts
5045  */
5047 
5048  /**
5049  * Byte position of currently parsed frame in stream.
5050  */
5051  int64_t pos;
5052 
5053  /**
5054  * Previous frame byte position.
5055  */
5056  int64_t last_pos;
5057 
5058  /**
5059  * Duration of the current frame.
5060  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5061  * For all other types, this is in units of AVCodecContext.time_base.
5062  */
5064 
5066 
5067  /**
5068  * Indicate whether a picture is coded as a frame, top field or bottom field.
5069  *
5070  * For example, H.264 field_pic_flag equal to 0 corresponds to
5071  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5072  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5073  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5074  */
5076 
5077  /**
5078  * Picture number incremented in presentation or output order.
5079  * This field may be reinitialized at the first picture of a new sequence.
5080  *
5081  * For example, this corresponds to H.264 PicOrderCnt.
5082  */
5084 
5085  /**
5086  * Dimensions of the decoded video intended for presentation.
5087  */
5088  int width;
5089  int height;
5090 
5091  /**
5092  * Dimensions of the coded video.
5093  */
5096 
5097  /**
5098  * The format of the coded data, corresponds to enum AVPixelFormat for video
5099  * and for enum AVSampleFormat for audio.
5100  *
5101  * Note that a decoder can have considerable freedom in how exactly it
5102  * decodes the data, so the format reported here might be different from the
5103  * one returned by a decoder.
5104  */
5105  int format;
5107 
5108 typedef struct AVCodecParser {
5109  int codec_ids[5]; /* several codec IDs are permitted */
5112  /* This callback never returns an error, a negative value means that
5113  * the frame start was in a previous packet. */
5115  AVCodecContext *avctx,
5116  const uint8_t **poutbuf, int *poutbuf_size,
5117  const uint8_t *buf, int buf_size);
5119  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5121 } AVCodecParser;
5122 
5124 
5127 
5128 /**
5129  * Parse a packet.
5130  *
5131  * @param s parser context.
5132  * @param avctx codec context.
5133  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5134  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5135  * @param buf input buffer.
5136  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5137  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5138  To signal EOF, this should be 0 (so that the last frame
5139  can be output).
5140  * @param pts input presentation timestamp.
5141  * @param dts input decoding timestamp.
5142  * @param pos input byte position in stream.
5143  * @return the number of bytes of the input bitstream used.
5144  *
5145  * Example:
5146  * @code
5147  * while(in_len){
5148  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5149  * in_data, in_len,
5150  * pts, dts, pos);
5151  * in_data += len;
5152  * in_len -= len;
5153  *
5154  * if(size)
5155  * decode_frame(data, size);
5156  * }
5157  * @endcode
5158  */
5160  AVCodecContext *avctx,
5161  uint8_t **poutbuf, int *poutbuf_size,
5162  const uint8_t *buf, int buf_size,
5163  int64_t pts, int64_t dts,
5164  int64_t pos);
5165 
5166 /**
5167  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5168  * @deprecated use AVBitStreamFilter
5169  */
5171  AVCodecContext *avctx,
5172  uint8_t **poutbuf, int *poutbuf_size,
5173  const uint8_t *buf, int buf_size, int keyframe);
5175 
5176 /**
5177  * @}
5178  * @}
5179  */
5180 
5181 /**
5182  * @addtogroup lavc_encoding
5183  * @{
5184  */
5185 
5186 /**
5187  * Find a registered encoder with a matching codec ID.
5188  *
5189  * @param id AVCodecID of the requested encoder
5190  * @return An encoder if one was found, NULL otherwise.
5191  */
5193 
5194 /**
5195  * Find a registered encoder with the specified name.
5196  *
5197  * @param name name of the requested encoder
5198  * @return An encoder if one was found, NULL otherwise.
5199  */
5201 
5202 /**
5203  * Encode a frame of audio.
5204  *
5205  * Takes input samples from frame and writes the next output packet, if
5206  * available, to avpkt. The output packet does not necessarily contain data for
5207  * the most recent frame, as encoders can delay, split, and combine input frames
5208  * internally as needed.
5209  *
5210  * @param avctx codec context
5211  * @param avpkt output AVPacket.
5212  * The user can supply an output buffer by setting
5213  * avpkt->data and avpkt->size prior to calling the
5214  * function, but if the size of the user-provided data is not
5215  * large enough, encoding will fail. If avpkt->data and
5216  * avpkt->size are set, avpkt->destruct must also be set. All
5217  * other AVPacket fields will be reset by the encoder using
5218  * av_init_packet(). If avpkt->data is NULL, the encoder will
5219  * allocate it. The encoder will set avpkt->size to the size
5220  * of the output packet.
5221  *
5222  * If this function fails or produces no output, avpkt will be
5223  * freed using av_packet_unref().
5224  * @param[in] frame AVFrame containing the raw audio data to be encoded.
5225  * May be NULL when flushing an encoder that has the
5226  * AV_CODEC_CAP_DELAY capability set.
5227  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5228  * can have any number of samples.
5229  * If it is not set, frame->nb_samples must be equal to
5230  * avctx->frame_size for all frames except the last.
5231  * The final frame may be smaller than avctx->frame_size.
5232  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5233  * output packet is non-empty, and to 0 if it is
5234  * empty. If the function returns an error, the
5235  * packet can be assumed to be invalid, and the
5236  * value of got_packet_ptr is undefined and should
5237  * not be used.
5238  * @return 0 on success, negative error code on failure
5239  *
5240  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5241  */
5243 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5244  const AVFrame *frame, int *got_packet_ptr);
5245 
5246 /**
5247  * Encode a frame of video.
5248  *
5249  * Takes input raw video data from frame and writes the next output packet, if
5250  * available, to avpkt. The output packet does not necessarily contain data for
5251  * the most recent frame, as encoders can delay and reorder input frames
5252  * internally as needed.
5253  *
5254  * @param avctx codec context
5255  * @param avpkt output AVPacket.
5256  * The user can supply an output buffer by setting
5257  * avpkt->data and avpkt->size prior to calling the
5258  * function, but if the size of the user-provided data is not
5259  * large enough, encoding will fail. All other AVPacket fields
5260  * will be reset by the encoder using av_init_packet(). If
5261  * avpkt->data is NULL, the encoder will allocate it.
5262  * The encoder will set avpkt->size to the size of the
5263  * output packet. The returned data (if any) belongs to the
5264  * caller, he is responsible for freeing it.
5265  *
5266  * If this function fails or produces no output, avpkt will be
5267  * freed using av_packet_unref().
5268  * @param[in] frame AVFrame containing the raw video data to be encoded.
5269  * May be NULL when flushing an encoder that has the
5270  * AV_CODEC_CAP_DELAY capability set.
5271  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5272  * output packet is non-empty, and to 0 if it is
5273  * empty. If the function returns an error, the
5274  * packet can be assumed to be invalid, and the
5275  * value of got_packet_ptr is undefined and should
5276  * not be used.
5277  * @return 0 on success, negative error code on failure
5278  *
5279  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5280  */
5282 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
5283  const AVFrame *frame, int *got_packet_ptr);
5284 
5285 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
5286  const AVSubtitle *sub);
5287 
5288 
5289 /**
5290  * @}
5291  */
5292 
5293 #if FF_API_AVPICTURE
5294 /**
5295  * @addtogroup lavc_picture
5296  * @{
5297  */
5298 
5299 /**
5300  * @deprecated unused
5301  */
5303 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
5304 
5305 /**
5306  * @deprecated unused
5307  */
5309 void avpicture_free(AVPicture *picture);
5310 
5311 /**
5312  * @deprecated use av_image_fill_arrays() instead.
5313  */
5315 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
5316  enum AVPixelFormat pix_fmt, int width, int height);
5317 
5318 /**
5319  * @deprecated use av_image_copy_to_buffer() instead.
5320  */
5323  int width, int height,
5324  unsigned char *dest, int dest_size);
5325 
5326 /**
5327  * @deprecated use av_image_get_buffer_size() instead.
5328  */
5331 
5332 /**
5333  * @deprecated av_image_copy() instead.
5334  */
5335 at