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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
413 
455 
456  /* various PCM "codecs" */
457  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
489 
494 
495  /* various ADPCM codecs */
527 
538 
539  /* AMR */
542 
543  /* RealAudio codecs*/
546 
547  /* various DPCM codecs */
552 
555 
556  /* audio codecs */
557  AV_CODEC_ID_MP2 = 0x15000,
558  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
575  AV_CODEC_ID_GSM, ///< as in Berlin toast format
587  AV_CODEC_ID_GSM_MS, /* as found in WAV */
625 
647 
648  /* subtitle codecs */
649  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
652  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
659 
676 
677  /* other specific kind of codecs (generally used for attachments) */
678  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
679  AV_CODEC_ID_TTF = 0x18000,
680 
681  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
690 
691 
692  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
693 
694  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
695  * stream (only used by libavformat) */
696  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
697  * stream (only used by libavformat) */
698  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
699  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
700 };
701 
702 /**
703  * This struct describes the properties of a single codec described by an
704  * AVCodecID.
705  * @see avcodec_descriptor_get()
706  */
707 typedef struct AVCodecDescriptor {
708  enum AVCodecID id;
710  /**
711  * Name of the codec described by this descriptor. It is non-empty and
712  * unique for each codec descriptor. It should contain alphanumeric
713  * characters and '_' only.
714  */
715  const char *name;
716  /**
717  * A more descriptive name for this codec. May be NULL.
718  */
719  const char *long_name;
720  /**
721  * Codec properties, a combination of AV_CODEC_PROP_* flags.
722  */
723  int props;
724  /**
725  * MIME type(s) associated with the codec.
726  * May be NULL; if not, a NULL-terminated array of MIME types.
727  * The first item is always non-NULL and is the preferred MIME type.
728  */
729  const char *const *mime_types;
730  /**
731  * If non-NULL, an array of profiles recognized for this codec.
732  * Terminated with FF_PROFILE_UNKNOWN.
733  */
734  const struct AVProfile *profiles;
736 
737 /**
738  * Codec uses only intra compression.
739  * Video and audio codecs only.
740  */
741 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
742 /**
743  * Codec supports lossy compression. Audio and video codecs only.
744  * @note a codec may support both lossy and lossless
745  * compression modes
746  */
747 #define AV_CODEC_PROP_LOSSY (1 << 1)
748 /**
749  * Codec supports lossless compression. Audio and video codecs only.
750  */
751 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
752 /**
753  * Codec supports frame reordering. That is, the coded order (the order in which
754  * the encoded packets are output by the encoders / stored / input to the
755  * decoders) may be different from the presentation order of the corresponding
756  * frames.
757  *
758  * For codecs that do not have this property set, PTS and DTS should always be
759  * equal.
760  */
761 #define AV_CODEC_PROP_REORDER (1 << 3)
762 /**
763  * Subtitle codec is bitmap based
764  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
765  */
766 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
767 /**
768  * Subtitle codec is text based.
769  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
770  */
771 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
772 
773 /**
774  * @ingroup lavc_decoding
775  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
776  * This is mainly needed because some optimized bitstream readers read
777  * 32 or 64 bit at once and could read over the end.<br>
778  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
779  * MPEG bitstreams could cause overread and segfault.
780  */
781 #define AV_INPUT_BUFFER_PADDING_SIZE 64
782 
783 /**
784  * @ingroup lavc_encoding
785  * minimum encoding buffer size
786  * Used to avoid some checks during header writing.
787  */
788 #define AV_INPUT_BUFFER_MIN_SIZE 16384
789 
790 /**
791  * @ingroup lavc_decoding
792  */
794  /* We leave some space between them for extensions (drop some
795  * keyframes for intra-only or drop just some bidir frames). */
796  AVDISCARD_NONE =-16, ///< discard nothing
797  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
798  AVDISCARD_NONREF = 8, ///< discard all non reference
799  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
800  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
801  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
802  AVDISCARD_ALL = 48, ///< discard all
803 };
804 
815  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
816 };
817 
818 /**
819  * @ingroup lavc_encoding
820  */
821 typedef struct RcOverride{
824  int qscale; // If this is 0 then quality_factor will be used instead.
826 } RcOverride;
827 
828 /* encoding support
829  These flags can be passed in AVCodecContext.flags before initialization.
830  Note: Not everything is supported yet.
831 */
832 
833 /**
834  * Allow decoders to produce frames with data planes that are not aligned
835  * to CPU requirements (e.g. due to cropping).
836  */
837 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
838 /**
839  * Use fixed qscale.
840  */
841 #define AV_CODEC_FLAG_QSCALE (1 << 1)
842 /**
843  * 4 MV per MB allowed / advanced prediction for H.263.
844  */
845 #define AV_CODEC_FLAG_4MV (1 << 2)
846 /**
847  * Output even those frames that might be corrupted.
848  */
849 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
850 /**
851  * Use qpel MC.
852  */
853 #define AV_CODEC_FLAG_QPEL (1 << 4)
854 /**
855  * Use internal 2pass ratecontrol in first pass mode.
856  */
857 #define AV_CODEC_FLAG_PASS1 (1 << 9)
858 /**
859  * Use internal 2pass ratecontrol in second pass mode.
860  */
861 #define AV_CODEC_FLAG_PASS2 (1 << 10)
862 /**
863  * loop filter.
864  */
865 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
866 /**
867  * Only decode/encode grayscale.
868  */
869 #define AV_CODEC_FLAG_GRAY (1 << 13)
870 /**
871  * error[?] variables will be set during encoding.
872  */
873 #define AV_CODEC_FLAG_PSNR (1 << 15)
874 /**
875  * Input bitstream might be truncated at a random location
876  * instead of only at frame boundaries.
877  */
878 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
879 /**
880  * Use interlaced DCT.
881  */
882 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
883 /**
884  * Force low delay.
885  */
886 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
887 /**
888  * Place global headers in extradata instead of every keyframe.
889  */
890 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
891 /**
892  * Use only bitexact stuff (except (I)DCT).
893  */
894 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
895 /* Fx : Flag for H.263+ extra options */
896 /**
897  * H.263 advanced intra coding / MPEG-4 AC prediction
898  */
899 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
900 /**
901  * interlaced motion estimation
902  */
903 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
904 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
905 
906 /**
907  * Allow non spec compliant speedup tricks.
908  */
909 #define AV_CODEC_FLAG2_FAST (1 << 0)
910 /**
911  * Skip bitstream encoding.
912  */
913 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
914 /**
915  * Place global headers at every keyframe instead of in extradata.
916  */
917 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
918 
919 /**
920  * timecode is in drop frame format. DEPRECATED!!!!
921  */
922 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
923 
924 /**
925  * Input bitstream might be truncated at a packet boundaries
926  * instead of only at frame boundaries.
927  */
928 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
929 /**
930  * Discard cropping information from SPS.
931  */
932 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
933 
934 /**
935  * Show all frames before the first keyframe
936  */
937 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
938 /**
939  * Export motion vectors through frame side data
940  */
941 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
942 /**
943  * Do not skip samples and export skip information as frame side data
944  */
945 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
946 /**
947  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
948  */
949 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
950 
951 /* Unsupported options :
952  * Syntax Arithmetic coding (SAC)
953  * Reference Picture Selection
954  * Independent Segment Decoding */
955 /* /Fx */
956 /* codec capabilities */
957 
958 /**
959  * Decoder can use draw_horiz_band callback.
960  */
961 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
962 /**
963  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
964  * If not set, it might not use get_buffer() at all or use operations that
965  * assume the buffer was allocated by avcodec_default_get_buffer.
966  */
967 #define AV_CODEC_CAP_DR1 (1 << 1)
968 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
969 /**
970  * Encoder or decoder requires flushing with NULL input at the end in order to
971  * give the complete and correct output.
972  *
973  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
974  * with NULL data. The user can still send NULL data to the public encode
975  * or decode function, but libavcodec will not pass it along to the codec
976  * unless this flag is set.
977  *
978  * Decoders:
979  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
980  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
981  * returns frames.
982  *
983  * Encoders:
984  * The encoder needs to be fed with NULL data at the end of encoding until the
985  * encoder no longer returns data.
986  *
987  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
988  * flag also means that the encoder must set the pts and duration for
989  * each output packet. If this flag is not set, the pts and duration will
990  * be determined by libavcodec from the input frame.
991  */
992 #define AV_CODEC_CAP_DELAY (1 << 5)
993 /**
994  * Codec can be fed a final frame with a smaller size.
995  * This can be used to prevent truncation of the last audio samples.
996  */
997 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
998 
999 /**
1000  * Codec can output multiple frames per AVPacket
1001  * Normally demuxers return one frame at a time, demuxers which do not do
1002  * are connected to a parser to split what they return into proper frames.
1003  * This flag is reserved to the very rare category of codecs which have a
1004  * bitstream that cannot be split into frames without timeconsuming
1005  * operations like full decoding. Demuxers carrying such bitstreams thus
1006  * may return multiple frames in a packet. This has many disadvantages like
1007  * prohibiting stream copy in many cases thus it should only be considered
1008  * as a last resort.
1009  */
1010 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1011 /**
1012  * Codec is experimental and is thus avoided in favor of non experimental
1013  * encoders
1014  */
1015 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1016 /**
1017  * Codec should fill in channel configuration and samplerate instead of container
1018  */
1019 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1020 /**
1021  * Codec supports frame-level multithreading.
1022  */
1023 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1024 /**
1025  * Codec supports slice-based (or partition-based) multithreading.
1026  */
1027 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1028 /**
1029  * Codec supports changed parameters at any point.
1030  */
1031 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1032 /**
1033  * Codec supports avctx->thread_count == 0 (auto).
1034  */
1035 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1036 /**
1037  * Audio encoder supports receiving a different number of samples in each call.
1038  */
1039 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1040 /**
1041  * Decoder is not a preferred choice for probing.
1042  * This indicates that the decoder is not a good choice for probing.
1043  * It could for example be an expensive to spin up hardware decoder,
1044  * or it could simply not provide a lot of useful information about
1045  * the stream.
1046  * A decoder marked with this flag should only be used as last resort
1047  * choice for probing.
1048  */
1049 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1050 /**
1051  * Codec is intra only.
1052  */
1053 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1054 /**
1055  * Codec is lossless.
1056  */
1057 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1058 
1059 /**
1060  * Codec is backed by a hardware implementation. Typically used to
1061  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1062  * avcodec_get_hw_config() instead.
1063  */
1064 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1065 
1066 /**
1067  * Codec is potentially backed by a hardware implementation, but not
1068  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1069  * implementation provides some sort of internal fallback.
1070  */
1071 #define AV_CODEC_CAP_HYBRID (1 << 19)
1072 
1073 /**
1074  * Pan Scan area.
1075  * This specifies the area which should be displayed.
1076  * Note there may be multiple such areas for one frame.
1077  */
1078 typedef struct AVPanScan {
1079  /**
1080  * id
1081  * - encoding: Set by user.
1082  * - decoding: Set by libavcodec.
1083  */
1084  int id;
1085 
1086  /**
1087  * width and height in 1/16 pel
1088  * - encoding: Set by user.
1089  * - decoding: Set by libavcodec.
1090  */
1091  int width;
1092  int height;
1093 
1094  /**
1095  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1096  * - encoding: Set by user.
1097  * - decoding: Set by libavcodec.
1098  */
1099  int16_t position[3][2];
1100 } AVPanScan;
1101 
1102 /**
1103  * This structure describes the bitrate properties of an encoded bitstream. It
1104  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1105  * parameters for H.264/HEVC.
1106  */
1107 typedef struct AVCPBProperties {
1108  /**
1109  * Maximum bitrate of the stream, in bits per second.
1110  * Zero if unknown or unspecified.
1111  */
1113  /**
1114  * Minimum bitrate of the stream, in bits per second.
1115  * Zero if unknown or unspecified.
1116  */
1118  /**
1119  * Average bitrate of the stream, in bits per second.
1120  * Zero if unknown or unspecified.
1121  */
1123 
1124  /**
1125  * The size of the buffer to which the ratecontrol is applied, in bits.
1126  * Zero if unknown or unspecified.
1127  */
1129 
1130  /**
1131  * The delay between the time the packet this structure is associated with
1132  * is received and the time when it should be decoded, in periods of a 27MHz
1133  * clock.
1134  *
1135  * UINT64_MAX when unknown or unspecified.
1136  */
1137  uint64_t vbv_delay;
1138 } AVCPBProperties;
1139 
1140 /**
1141  * The decoder will keep a reference to the frame and may reuse it later.
1142  */
1143 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1144 
1145 /**
1146  * @defgroup lavc_packet AVPacket
1147  *
1148  * Types and functions for working with AVPacket.
1149  * @{
1150  */
1152  /**
1153  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1154  * bytes worth of palette. This side data signals that a new palette is
1155  * present.
1156  */
1158 
1159  /**
1160  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1161  * that the extradata buffer was changed and the receiving side should
1162  * act upon it appropriately. The new extradata is embedded in the side
1163  * data buffer and should be immediately used for processing the current
1164  * frame or packet.
1165  */
1167 
1168  /**
1169  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1170  * @code
1171  * u32le param_flags
1172  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1173  * s32le channel_count
1174  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1175  * u64le channel_layout
1176  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1177  * s32le sample_rate
1178  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1179  * s32le width
1180  * s32le height
1181  * @endcode
1182  */
1184 
1185  /**
1186  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1187  * structures with info about macroblocks relevant to splitting the
1188  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1189  * That is, it does not necessarily contain info about all macroblocks,
1190  * as long as the distance between macroblocks in the info is smaller
1191  * than the target payload size.
1192  * Each MB info structure is 12 bytes, and is laid out as follows:
1193  * @code
1194  * u32le bit offset from the start of the packet
1195  * u8 current quantizer at the start of the macroblock
1196  * u8 GOB number
1197  * u16le macroblock address within the GOB
1198  * u8 horizontal MV predictor
1199  * u8 vertical MV predictor
1200  * u8 horizontal MV predictor for block number 3
1201  * u8 vertical MV predictor for block number 3
1202  * @endcode
1203  */
1205 
1206  /**
1207  * This side data should be associated with an audio stream and contains
1208  * ReplayGain information in form of the AVReplayGain struct.
1209  */
1211 
1212  /**
1213  * This side data contains a 3x3 transformation matrix describing an affine
1214  * transformation that needs to be applied to the decoded video frames for
1215  * correct presentation.
1216  *
1217  * See libavutil/display.h for a detailed description of the data.
1218  */
1220 
1221  /**
1222  * This side data should be associated with a video stream and contains
1223  * Stereoscopic 3D information in form of the AVStereo3D struct.
1224  */
1226 
1227  /**
1228  * This side data should be associated with an audio stream and corresponds
1229  * to enum AVAudioServiceType.
1230  */
1232 
1233  /**
1234  * This side data contains quality related information from the encoder.
1235  * @code
1236  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1237  * u8 picture type
1238  * u8 error count
1239  * u16 reserved
1240  * u64le[error count] sum of squared differences between encoder in and output
1241  * @endcode
1242  */
1244 
1245  /**
1246  * This side data contains an integer value representing the stream index
1247  * of a "fallback" track. A fallback track indicates an alternate
1248  * track to use when the current track can not be decoded for some reason.
1249  * e.g. no decoder available for codec.
1250  */
1252 
1253  /**
1254  * This side data corresponds to the AVCPBProperties struct.
1255  */
1257 
1258  /**
1259  * Recommmends skipping the specified number of samples
1260  * @code
1261  * u32le number of samples to skip from start of this packet
1262  * u32le number of samples to skip from end of this packet
1263  * u8 reason for start skip
1264  * u8 reason for end skip (0=padding silence, 1=convergence)
1265  * @endcode
1266  */
1268 
1269  /**
1270  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1271  * the packet may contain "dual mono" audio specific to Japanese DTV
1272  * and if it is true, recommends only the selected channel to be used.
1273  * @code
1274  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1275  * @endcode
1276  */
1278 
1279  /**
1280  * A list of zero terminated key/value strings. There is no end marker for
1281  * the list, so it is required to rely on the side data size to stop.
1282  */
1284 
1285  /**
1286  * Subtitle event position
1287  * @code
1288  * u32le x1
1289  * u32le y1
1290  * u32le x2
1291  * u32le y2
1292  * @endcode
1293  */
1295 
1296  /**
1297  * Data found in BlockAdditional element of matroska container. There is
1298  * no end marker for the data, so it is required to rely on the side data
1299  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1300  * by data.
1301  */
1303 
1304  /**
1305  * The optional first identifier line of a WebVTT cue.
1306  */
1308 
1309  /**
1310  * The optional settings (rendering instructions) that immediately
1311  * follow the timestamp specifier of a WebVTT cue.
1312  */
1314 
1315  /**
1316  * A list of zero terminated key/value strings. There is no end marker for
1317  * the list, so it is required to rely on the side data size to stop. This
1318  * side data includes updated metadata which appeared in the stream.
1319  */
1321 
1322  /**
1323  * MPEGTS stream ID, this is required to pass the stream ID
1324  * information from the demuxer to the corresponding muxer.
1325  */
1327 
1328  /**
1329  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1330  * should be associated with a video stream and contains data in the form
1331  * of the AVMasteringDisplayMetadata struct.
1332  */
1334 
1335  /**
1336  * This side data should be associated with a video stream and corresponds
1337  * to the AVSphericalMapping structure.
1338  */
1340 
1341  /**
1342  * Content light level (based on CTA-861.3). This metadata should be
1343  * associated with a video stream and contains data in the form of the
1344  * AVContentLightMetadata struct.
1345  */
1347 
1348  /**
1349  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1350  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1351  * The number of bytes of CC data is AVPacketSideData.size.
1352  */
1354 
1355  /**
1356  * This side data is encryption initialization data.
1357  * The format is not part of ABI, use av_encryption_init_info_* methods to
1358  * access.
1359  */
1361 
1362  /**
1363  * This side data contains encryption info for how to decrypt the packet.
1364  * The format is not part of ABI, use av_encryption_info_* methods to access.
1365  */
1367 
1368  /**
1369  * Active Format Description data consisting of a single byte as specified
1370  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
1371  */
1373 
1374  /**
1375  * The number of side data types.
1376  * This is not part of the public API/ABI in the sense that it may
1377  * change when new side data types are added.
1378  * This must stay the last enum value.
1379  * If its value becomes huge, some code using it
1380  * needs to be updated as it assumes it to be smaller than other limits.
1381  */
1383 };
1384 
1385 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1386 
1387 typedef struct AVPacketSideData {
1389  int size;
1392 
1393 /**
1394  * This structure stores compressed data. It is typically exported by demuxers
1395  * and then passed as input to decoders, or received as output from encoders and
1396  * then passed to muxers.
1397  *
1398  * For video, it should typically contain one compressed frame. For audio it may
1399  * contain several compressed frames. Encoders are allowed to output empty
1400  * packets, with no compressed data, containing only side data
1401  * (e.g. to update some stream parameters at the end of encoding).
1402  *
1403  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1404  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1405  * without libavcodec and libavformat major bump.
1406  *
1407  * The semantics of data ownership depends on the buf field.
1408  * If it is set, the packet data is dynamically allocated and is
1409  * valid indefinitely until a call to av_packet_unref() reduces the
1410  * reference count to 0.
1411  *
1412  * If the buf field is not set av_packet_ref() would make a copy instead
1413  * of increasing the reference count.
1414  *
1415  * The side data is always allocated with av_malloc(), copied by
1416  * av_packet_ref() and freed by av_packet_unref().
1417  *
1418  * @see av_packet_ref
1419  * @see av_packet_unref
1420  */
1421 typedef struct AVPacket {
1422  /**
1423  * A reference to the reference-counted buffer where the packet data is
1424  * stored.
1425  * May be NULL, then the packet data is not reference-counted.
1426  */
1428  /**
1429  * Presentation timestamp in AVStream->time_base units; the time at which
1430  * the decompressed packet will be presented to the user.
1431  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1432  * pts MUST be larger or equal to dts as presentation cannot happen before
1433  * decompression, unless one wants to view hex dumps. Some formats misuse
1434  * the terms dts and pts/cts to mean something different. Such timestamps
1435  * must be converted to true pts/dts before they are stored in AVPacket.
1436  */
1437  int64_t pts;
1438  /**
1439  * Decompression timestamp in AVStream->time_base units; the time at which
1440  * the packet is decompressed.
1441  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1442  */
1443  int64_t dts;
1445  int size;
1447  /**
1448  * A combination of AV_PKT_FLAG values
1449  */
1450  int flags;
1451  /**
1452  * Additional packet data that can be provided by the container.
1453  * Packet can contain several types of side information.
1454  */
1457 
1458  /**
1459  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1460  * Equals next_pts - this_pts in presentation order.
1461  */
1462  int64_t duration;
1463 
1464  int64_t pos; ///< byte position in stream, -1 if unknown
1465 
1466 #if FF_API_CONVERGENCE_DURATION
1467  /**
1468  * @deprecated Same as the duration field, but as int64_t. This was required
1469  * for Matroska subtitles, whose duration values could overflow when the
1470  * duration field was still an int.
1471  */
1474 #endif
1475 } AVPacket;
1476 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1477 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1478 /**
1479  * Flag is used to discard packets which are required to maintain valid
1480  * decoder state but are not required for output and should be dropped
1481  * after decoding.
1482  **/
1483 #define AV_PKT_FLAG_DISCARD 0x0004
1484 /**
1485  * The packet comes from a trusted source.
1486  *
1487  * Otherwise-unsafe constructs such as arbitrary pointers to data
1488  * outside the packet may be followed.
1489  */
1490 #define AV_PKT_FLAG_TRUSTED 0x0008
1491 /**
1492  * Flag is used to indicate packets that contain frames that can
1493  * be discarded by the decoder. I.e. Non-reference frames.
1494  */
1495 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1496 
1497 
1503 };
1504 /**
1505  * @}
1506  */
1507 
1508 struct AVCodecInternal;
1509 
1513  AV_FIELD_TT, //< Top coded_first, top displayed first
1514  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1515  AV_FIELD_TB, //< Top coded first, bottom displayed first
1516  AV_FIELD_BT, //< Bottom coded first, top displayed first
1517 };
1518 
1519 /**
1520  * main external API structure.
1521  * New fields can be added to the end with minor version bumps.
1522  * Removal, reordering and changes to existing fields require a major
1523  * version bump.
1524  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1525  * applications.
1526  * The name string for AVOptions options matches the associated command line
1527  * parameter name and can be found in libavcodec/options_table.h
1528  * The AVOption/command line parameter names differ in some cases from the C
1529  * structure field names for historic reasons or brevity.
1530  * sizeof(AVCodecContext) must not be used outside libav*.
1531  */
1532 typedef struct AVCodecContext {
1533  /**
1534  * information on struct for av_log
1535  * - set by avcodec_alloc_context3
1536  */
1539 
1540  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1541  const struct AVCodec *codec;
1542  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1543 
1544  /**
1545  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1546  * This is used to work around some encoder bugs.
1547  * A demuxer should set this to what is stored in the field used to identify the codec.
1548  * If there are multiple such fields in a container then the demuxer should choose the one
1549  * which maximizes the information about the used codec.
1550  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1551  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1552  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1553  * first.
1554  * - encoding: Set by user, if not then the default based on codec_id will be used.
1555  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1556  */
1557  unsigned int codec_tag;
1558 
1559  void *priv_data;
1560 
1561  /**
1562  * Private context used for internal data.
1563  *
1564  * Unlike priv_data, this is not codec-specific. It is used in general
1565  * libavcodec functions.
1566  */
1567  struct AVCodecInternal *internal;
1568 
1569  /**
1570  * Private data of the user, can be used to carry app specific stuff.
1571  * - encoding: Set by user.
1572  * - decoding: Set by user.
1573  */
1574  void *opaque;
1575 
1576  /**
1577  * the average bitrate
1578  * - encoding: Set by user; unused for constant quantizer encoding.
1579  * - decoding: Set by user, may be overwritten by libavcodec
1580  * if this info is available in the stream
1581  */
1582  int64_t bit_rate;
1583 
1584  /**
1585  * number of bits the bitstream is allowed to diverge from the reference.
1586  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1587  * - encoding: Set by user; unused for constant quantizer encoding.
1588  * - decoding: unused
1589  */
1591 
1592  /**
1593  * Global quality for codecs which cannot change it per frame.
1594  * This should be proportional to MPEG-1/2/4 qscale.
1595  * - encoding: Set by user.
1596  * - decoding: unused
1597  */
1599 
1600  /**
1601  * - encoding: Set by user.
1602  * - decoding: unused
1603  */
1605 #define FF_COMPRESSION_DEFAULT -1
1606 
1607  /**
1608  * AV_CODEC_FLAG_*.
1609  * - encoding: Set by user.
1610  * - decoding: Set by user.
1611  */
1612  int flags;
1613 
1614  /**
1615  * AV_CODEC_FLAG2_*
1616  * - encoding: Set by user.
1617  * - decoding: Set by user.
1618  */
1619  int flags2;
1620 
1621  /**
1622  * some codecs need / can use extradata like Huffman tables.
1623  * MJPEG: Huffman tables
1624  * rv10: additional flags
1625  * MPEG-4: global headers (they can be in the bitstream or here)
1626  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1627  * than extradata_size to avoid problems if it is read with the bitstream reader.
1628  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1629  * Must be allocated with the av_malloc() family of functions.
1630  * - encoding: Set/allocated/freed by libavcodec.
1631  * - decoding: Set/allocated/freed by user.
1632  */
1635 
1636  /**
1637  * This is the fundamental unit of time (in seconds) in terms
1638  * of which frame timestamps are represented. For fixed-fps content,
1639  * timebase should be 1/framerate and timestamp increments should be
1640  * identically 1.
1641  * This often, but not always is the inverse of the frame rate or field rate
1642  * for video. 1/time_base is not the average frame rate if the frame rate is not
1643  * constant.
1644  *
1645  * Like containers, elementary streams also can store timestamps, 1/time_base
1646  * is the unit in which these timestamps are specified.
1647  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1648  * vop_time_increment_resolution and fixed_vop_rate
1649  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1650  *
1651  * - encoding: MUST be set by user.
1652  * - decoding: the use of this field for decoding is deprecated.
1653  * Use framerate instead.
1654  */
1656 
1657  /**
1658  * For some codecs, the time base is closer to the field rate than the frame rate.
1659  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1660  * if no telecine is used ...
1661  *
1662  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1663  */
1665 
1666  /**
1667  * Codec delay.
1668  *
1669  * Encoding: Number of frames delay there will be from the encoder input to
1670  * the decoder output. (we assume the decoder matches the spec)
1671  * Decoding: Number of frames delay in addition to what a standard decoder
1672  * as specified in the spec would produce.
1673  *
1674  * Video:
1675  * Number of frames the decoded output will be delayed relative to the
1676  * encoded input.
1677  *
1678  * Audio:
1679  * For encoding, this field is unused (see initial_padding).
1680  *
1681  * For decoding, this is the number of samples the decoder needs to
1682  * output before the decoder's output is valid. When seeking, you should
1683  * start decoding this many samples prior to your desired seek point.
1684  *
1685  * - encoding: Set by libavcodec.
1686  * - decoding: Set by libavcodec.
1687  */
1688  int delay;
1689 
1690 
1691  /* video only */
1692  /**
1693  * picture width / height.
1694  *
1695  * @note Those fields may not match the values of the last
1696  * AVFrame output by avcodec_decode_video2 due frame
1697  * reordering.
1698  *
1699  * - encoding: MUST be set by user.
1700  * - decoding: May be set by the user before opening the decoder if known e.g.
1701  * from the container. Some decoders will require the dimensions
1702  * to be set by the caller. During decoding, the decoder may
1703  * overwrite those values as required while parsing the data.
1704  */
1706 
1707  /**
1708  * Bitstream width / height, may be different from width/height e.g. when
1709  * the decoded frame is cropped before being output or lowres is enabled.
1710  *
1711  * @note Those field may not match the value of the last
1712  * AVFrame output by avcodec_receive_frame() due frame
1713  * reordering.
1714  *
1715  * - encoding: unused
1716  * - decoding: May be set by the user before opening the decoder if known
1717  * e.g. from the container. During decoding, the decoder may
1718  * overwrite those values as required while parsing the data.
1719  */
1721 
1722  /**
1723  * the number of pictures in a group of pictures, or 0 for intra_only
1724  * - encoding: Set by user.
1725  * - decoding: unused
1726  */
1728 
1729  /**
1730  * Pixel format, see AV_PIX_FMT_xxx.
1731  * May be set by the demuxer if known from headers.
1732  * May be overridden by the decoder if it knows better.
1733  *
1734  * @note This field may not match the value of the last
1735  * AVFrame output by avcodec_receive_frame() due frame
1736  * reordering.
1737  *
1738  * - encoding: Set by user.
1739  * - decoding: Set by user if known, overridden by libavcodec while
1740  * parsing the data.
1741  */
1743 
1744  /**
1745  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1746  * decoder to draw a horizontal band. It improves cache usage. Not
1747  * all codecs can do that. You must check the codec capabilities
1748  * beforehand.
1749  * When multithreading is used, it may be called from multiple threads
1750  * at the same time; threads might draw different parts of the same AVFrame,
1751  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1752  * in order.
1753  * The function is also used by hardware acceleration APIs.
1754  * It is called at least once during frame decoding to pass
1755  * the data needed for hardware render.
1756  * In that mode instead of pixel data, AVFrame points to
1757  * a structure specific to the acceleration API. The application
1758  * reads the structure and can change some fields to indicate progress
1759  * or mark state.
1760  * - encoding: unused
1761  * - decoding: Set by user.
1762  * @param height the height of the slice
1763  * @param y the y position of the slice
1764  * @param type 1->top field, 2->bottom field, 3->frame
1765  * @param offset offset into the AVFrame.data from which the slice should be read
1766  */
1768  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1769  int y, int type, int height);
1770 
1771  /**
1772  * callback to negotiate the pixelFormat
1773  * @param fmt is the list of formats which are supported by the codec,
1774  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1775  * The first is always the native one.
1776  * @note The callback may be called again immediately if initialization for
1777  * the selected (hardware-accelerated) pixel format failed.
1778  * @warning Behavior is undefined if the callback returns a value not
1779  * in the fmt list of formats.
1780  * @return the chosen format
1781  * - encoding: unused
1782  * - decoding: Set by user, if not set the native format will be chosen.
1783  */
1784  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1785 
1786  /**
1787  * maximum number of B-frames between non-B-frames
1788  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1789  * - encoding: Set by user.
1790  * - decoding: unused
1791  */
1793 
1794  /**
1795  * qscale factor between IP and B-frames
1796  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1797  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1798  * - encoding: Set by user.
1799  * - decoding: unused
1800  */
1802 
1803 #if FF_API_PRIVATE_OPT
1804  /** @deprecated use encoder private options instead */
1807 #endif
1808 
1809  /**
1810  * qscale offset between IP and B-frames
1811  * - encoding: Set by user.
1812  * - decoding: unused
1813  */
1815 
1816  /**
1817  * Size of the frame reordering buffer in the decoder.
1818  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1819  * - encoding: Set by libavcodec.
1820  * - decoding: Set by libavcodec.
1821  */
1823 
1824 #if FF_API_PRIVATE_OPT
1825  /** @deprecated use encoder private options instead */
1828 #endif
1829 
1830  /**
1831  * qscale factor between P- and I-frames
1832  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1833  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1834  * - encoding: Set by user.
1835  * - decoding: unused
1836  */
1838 
1839  /**
1840  * qscale offset between P and I-frames
1841  * - encoding: Set by user.
1842  * - decoding: unused
1843  */
1845 
1846  /**
1847  * luminance masking (0-> disabled)
1848  * - encoding: Set by user.
1849  * - decoding: unused
1850  */
1852 
1853  /**
1854  * temporary complexity masking (0-> disabled)
1855  * - encoding: Set by user.
1856  * - decoding: unused
1857  */
1859 
1860  /**
1861  * spatial complexity masking (0-> disabled)
1862  * - encoding: Set by user.
1863  * - decoding: unused
1864  */
1866 
1867  /**
1868  * p block masking (0-> disabled)
1869  * - encoding: Set by user.
1870  * - decoding: unused
1871  */
1872  float p_masking;
1873 
1874  /**
1875  * darkness masking (0-> disabled)
1876  * - encoding: Set by user.
1877  * - decoding: unused
1878  */
1880 
1881  /**
1882  * slice count
1883  * - encoding: Set by libavcodec.
1884  * - decoding: Set by user (or 0).
1885  */
1887 
1888 #if FF_API_PRIVATE_OPT
1889  /** @deprecated use encoder private options instead */
1892 #define FF_PRED_LEFT 0
1893 #define FF_PRED_PLANE 1
1894 #define FF_PRED_MEDIAN 2
1895 #endif
1896 
1897  /**
1898  * slice offsets in the frame in bytes
1899  * - encoding: Set/allocated by libavcodec.
1900  * - decoding: Set/allocated by user (or NULL).
1901  */
1903 
1904  /**
1905  * sample aspect ratio (0 if unknown)
1906  * That is the width of a pixel divided by the height of the pixel.
1907  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1908  * - encoding: Set by user.
1909  * - decoding: Set by libavcodec.
1910  */
1912 
1913  /**
1914  * motion estimation comparison function
1915  * - encoding: Set by user.
1916  * - decoding: unused
1917  */
1918  int me_cmp;
1919  /**
1920  * subpixel motion estimation comparison function
1921  * - encoding: Set by user.
1922  * - decoding: unused
1923  */
1925  /**
1926  * macroblock comparison function (not supported yet)
1927  * - encoding: Set by user.
1928  * - decoding: unused
1929  */
1930  int mb_cmp;
1931  /**
1932  * interlaced DCT comparison function
1933  * - encoding: Set by user.
1934  * - decoding: unused
1935  */
1937 #define FF_CMP_SAD 0
1938 #define FF_CMP_SSE 1
1939 #define FF_CMP_SATD 2
1940 #define FF_CMP_DCT 3
1941 #define FF_CMP_PSNR 4
1942 #define FF_CMP_BIT 5
1943 #define FF_CMP_RD 6
1944 #define FF_CMP_ZERO 7
1945 #define FF_CMP_VSAD 8
1946 #define FF_CMP_VSSE 9
1947 #define FF_CMP_NSSE 10
1948 #define FF_CMP_W53 11
1949 #define FF_CMP_W97 12
1950 #define FF_CMP_DCTMAX 13
1951 #define FF_CMP_DCT264 14
1952 #define FF_CMP_MEDIAN_SAD 15
1953 #define FF_CMP_CHROMA 256
1954 
1955  /**
1956  * ME diamond size & shape
1957  * - encoding: Set by user.
1958  * - decoding: unused
1959  */
1961 
1962  /**
1963  * amount of previous MV predictors (2a+1 x 2a+1 square)
1964  * - encoding: Set by user.
1965  * - decoding: unused
1966  */
1968 
1969 #if FF_API_PRIVATE_OPT
1970  /** @deprecated use encoder private options instead */
1972  int pre_me;
1973 #endif
1974 
1975  /**
1976  * motion estimation prepass comparison function
1977  * - encoding: Set by user.
1978  * - decoding: unused
1979  */
1981 
1982  /**
1983  * ME prepass diamond size & shape
1984  * - encoding: Set by user.
1985  * - decoding: unused
1986  */
1988 
1989  /**
1990  * subpel ME quality
1991  * - encoding: Set by user.
1992  * - decoding: unused
1993  */
1995 
1996  /**
1997  * maximum motion estimation search range in subpel units
1998  * If 0 then no limit.
1999  *
2000  * - encoding: Set by user.
2001  * - decoding: unused
2002  */
2004 
2005  /**
2006  * slice flags
2007  * - encoding: unused
2008  * - decoding: Set by user.
2009  */
2011 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2012 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2013 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2014 
2015  /**
2016  * macroblock decision mode
2017  * - encoding: Set by user.
2018  * - decoding: unused
2019  */
2021 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2022 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2023 #define FF_MB_DECISION_RD 2 ///< rate distortion
2024 
2025  /**
2026  * custom intra quantization matrix
2027  * - encoding: Set by user, can be NULL.
2028  * - decoding: Set by libavcodec.
2029  */
2030  uint16_t *intra_matrix;
2031 
2032  /**
2033  * custom inter quantization matrix
2034  * - encoding: Set by user, can be NULL.
2035  * - decoding: Set by libavcodec.
2036  */
2037  uint16_t *inter_matrix;
2038 
2039 #if FF_API_PRIVATE_OPT
2040  /** @deprecated use encoder private options instead */
2043 
2044  /** @deprecated use encoder private options instead */
2047 #endif
2048 
2049  /**
2050  * precision of the intra DC coefficient - 8
2051  * - encoding: Set by user.
2052  * - decoding: Set by libavcodec
2053  */
2055 
2056  /**
2057  * Number of macroblock rows at the top which are skipped.
2058  * - encoding: unused
2059  * - decoding: Set by user.
2060  */
2062 
2063  /**
2064  * Number of macroblock rows at the bottom which are skipped.
2065  * - encoding: unused
2066  * - decoding: Set by user.
2067  */
2069 
2070  /**
2071  * minimum MB Lagrange multiplier
2072  * - encoding: Set by user.
2073  * - decoding: unused
2074  */
2075  int mb_lmin;
2076 
2077  /**
2078  * maximum MB Lagrange multiplier
2079  * - encoding: Set by user.
2080  * - decoding: unused
2081  */
2082  int mb_lmax;
2083 
2084 #if FF_API_PRIVATE_OPT
2085  /**
2086  * @deprecated use encoder private options instead
2087  */
2090 #endif
2091 
2092  /**
2093  * - encoding: Set by user.
2094  * - decoding: unused
2095  */
2097 
2098 #if FF_API_PRIVATE_OPT
2099  /** @deprecated use encoder private options instead */
2102 #endif
2103 
2104  /**
2105  * minimum GOP size
2106  * - encoding: Set by user.
2107  * - decoding: unused
2108  */
2110 
2111  /**
2112  * number of reference frames
2113  * - encoding: Set by user.
2114  * - decoding: Set by lavc.
2115  */
2116  int refs;
2117 
2118 #if FF_API_PRIVATE_OPT
2119  /** @deprecated use encoder private options instead */
2122 #endif
2123 
2124  /**
2125  * Note: Value depends upon the compare function used for fullpel ME.
2126  * - encoding: Set by user.
2127  * - decoding: unused
2128  */
2130 
2131 #if FF_API_PRIVATE_OPT
2132  /** @deprecated use encoder private options instead */
2135 #endif
2136 
2137  /**
2138  * Chromaticity coordinates of the source primaries.
2139  * - encoding: Set by user
2140  * - decoding: Set by libavcodec
2141  */
2143 
2144  /**
2145  * Color Transfer Characteristic.
2146  * - encoding: Set by user
2147  * - decoding: Set by libavcodec
2148  */
2150 
2151  /**
2152  * YUV colorspace type.
2153  * - encoding: Set by user
2154  * - decoding: Set by libavcodec
2155  */
2157 
2158  /**
2159  * MPEG vs JPEG YUV range.
2160  * - encoding: Set by user
2161  * - decoding: Set by libavcodec
2162  */
2164 
2165  /**
2166  * This defines the location of chroma samples.
2167  * - encoding: Set by user
2168  * - decoding: Set by libavcodec
2169  */
2171 
2172  /**
2173  * Number of slices.
2174  * Indicates number of picture subdivisions. Used for parallelized
2175  * decoding.
2176  * - encoding: Set by user
2177  * - decoding: unused
2178  */
2179  int slices;
2180 
2181  /** Field order
2182  * - encoding: set by libavcodec
2183  * - decoding: Set by user.
2184  */
2186 
2187  /* audio only */
2188  int sample_rate; ///< samples per second
2189  int channels; ///< number of audio channels
2190 
2191  /**
2192  * audio sample format
2193  * - encoding: Set by user.
2194  * - decoding: Set by libavcodec.
2195  */
2196  enum AVSampleFormat sample_fmt; ///< sample format
2197 
2198  /* The following data should not be initialized. */
2199  /**
2200  * Number of samples per channel in an audio frame.
2201  *
2202  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2203  * except the last must contain exactly frame_size samples per channel.
2204  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2205  * frame size is not restricted.
2206  * - decoding: may be set by some decoders to indicate constant frame size
2207  */
2209 
2210  /**
2211  * Frame counter, set by libavcodec.
2212  *
2213  * - decoding: total number of frames returned from the decoder so far.
2214  * - encoding: total number of frames passed to the encoder so far.
2215  *
2216  * @note the counter is not incremented if encoding/decoding resulted in
2217  * an error.
2218  */
2220 
2221  /**
2222  * number of bytes per packet if constant and known or 0
2223  * Used by some WAV based audio codecs.
2224  */
2226 
2227  /**
2228  * Audio cutoff bandwidth (0 means "automatic")
2229  * - encoding: Set by user.
2230  * - decoding: unused
2231  */
2232  int cutoff;
2233 
2234  /**
2235  * Audio channel layout.
2236  * - encoding: set by user.
2237  * - decoding: set by user, may be overwritten by libavcodec.
2238  */
2239  uint64_t channel_layout;
2240 
2241  /**
2242  * Request decoder to use this channel layout if it can (0 for default)
2243  * - encoding: unused
2244  * - decoding: Set by user.
2245  */
2247 
2248  /**
2249  * Type of service that the audio stream conveys.
2250  * - encoding: Set by user.
2251  * - decoding: Set by libavcodec.
2252  */
2254 
2255  /**
2256  * desired sample format
2257  * - encoding: Not used.
2258  * - decoding: Set by user.
2259  * Decoder will decode to this format if it can.
2260  */
2262 
2263  /**
2264  * This callback is called at the beginning of each frame to get data
2265  * buffer(s) for it. There may be one contiguous buffer for all the data or
2266  * there may be a buffer per each data plane or anything in between. What
2267  * this means is, you may set however many entries in buf[] you feel necessary.
2268  * Each buffer must be reference-counted using the AVBuffer API (see description
2269  * of buf[] below).
2270  *
2271  * The following fields will be set in the frame before this callback is
2272  * called:
2273  * - format
2274  * - width, height (video only)
2275  * - sample_rate, channel_layout, nb_samples (audio only)
2276  * Their values may differ from the corresponding values in
2277  * AVCodecContext. This callback must use the frame values, not the codec
2278  * context values, to calculate the required buffer size.
2279  *
2280  * This callback must fill the following fields in the frame:
2281  * - data[]
2282  * - linesize[]
2283  * - extended_data:
2284  * * if the data is planar audio with more than 8 channels, then this
2285  * callback must allocate and fill extended_data to contain all pointers
2286  * to all data planes. data[] must hold as many pointers as it can.
2287  * extended_data must be allocated with av_malloc() and will be freed in
2288  * av_frame_unref().
2289  * * otherwise extended_data must point to data
2290  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2291  * the frame's data and extended_data pointers must be contained in these. That
2292  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2293  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2294  * and av_buffer_ref().
2295  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2296  * this callback and filled with the extra buffers if there are more
2297  * buffers than buf[] can hold. extended_buf will be freed in
2298  * av_frame_unref().
2299  *
2300  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2301  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2302  * some other means.
2303  *
2304  * Each data plane must be aligned to the maximum required by the target
2305  * CPU.
2306  *
2307  * @see avcodec_default_get_buffer2()
2308  *
2309  * Video:
2310  *
2311  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2312  * (read and/or written to if it is writable) later by libavcodec.
2313  *
2314  * avcodec_align_dimensions2() should be used to find the required width and
2315  * height, as they normally need to be rounded up to the next multiple of 16.
2316  *
2317  * Some decoders do not support linesizes changing between frames.
2318  *
2319  * If frame multithreading is used and thread_safe_callbacks is set,
2320  * this callback may be called from a different thread, but not from more
2321  * than one at once. Does not need to be reentrant.
2322  *
2323  * @see avcodec_align_dimensions2()
2324  *
2325  * Audio:
2326  *
2327  * Decoders request a buffer of a particular size by setting
2328  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2329  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2330  * to a smaller value in the output frame.
2331  *
2332  * As a convenience, av_samples_get_buffer_size() and
2333  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2334  * functions to find the required data size and to fill data pointers and
2335  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2336  * since all planes must be the same size.
2337  *
2338  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2339  *
2340  * - encoding: unused
2341  * - decoding: Set by libavcodec, user can override.
2342  */
2344 
2345  /**
2346  * If non-zero, the decoded audio and video frames returned from
2347  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2348  * and are valid indefinitely. The caller must free them with
2349  * av_frame_unref() when they are not needed anymore.
2350  * Otherwise, the decoded frames must not be freed by the caller and are
2351  * only valid until the next decode call.
2352  *
2353  * This is always automatically enabled if avcodec_receive_frame() is used.
2354  *
2355  * - encoding: unused
2356  * - decoding: set by the caller before avcodec_open2().
2357  */
2360 
2361  /* - encoding parameters */
2362  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2363  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2364 
2365  /**
2366  * minimum quantizer
2367  * - encoding: Set by user.
2368  * - decoding: unused
2369  */
2370  int qmin;
2371 
2372  /**
2373  * maximum quantizer
2374  * - encoding: Set by user.
2375  * - decoding: unused
2376  */
2377  int qmax;
2378 
2379  /**
2380  * maximum quantizer difference between frames
2381  * - encoding: Set by user.
2382  * - decoding: unused
2383  */
2385 
2386  /**
2387  * decoder bitstream buffer size
2388  * - encoding: Set by user.
2389  * - decoding: unused
2390  */
2392 
2393  /**
2394  * ratecontrol override, see RcOverride
2395  * - encoding: Allocated/set/freed by user.
2396  * - decoding: unused
2397  */
2400 
2401  /**
2402  * maximum bitrate
2403  * - encoding: Set by user.
2404  * - decoding: Set by user, may be overwritten by libavcodec.
2405  */
2406  int64_t rc_max_rate;
2407 
2408  /**
2409  * minimum bitrate
2410  * - encoding: Set by user.
2411  * - decoding: unused
2412  */
2413  int64_t rc_min_rate;
2414 
2415  /**
2416  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2417  * - encoding: Set by user.
2418  * - decoding: unused.
2419  */
2421 
2422  /**
2423  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2424  * - encoding: Set by user.
2425  * - decoding: unused.
2426  */
2428 
2429  /**
2430  * Number of bits which should be loaded into the rc buffer before decoding starts.
2431  * - encoding: Set by user.
2432  * - decoding: unused
2433  */
2435 
2436 #if FF_API_CODER_TYPE
2437 #define FF_CODER_TYPE_VLC 0
2438 #define FF_CODER_TYPE_AC 1
2439 #define FF_CODER_TYPE_RAW 2
2440 #define FF_CODER_TYPE_RLE 3
2441  /**
2442  * @deprecated use encoder private options instead
2443  */
2446 #endif /* FF_API_CODER_TYPE */
2447 
2448 #if FF_API_PRIVATE_OPT
2449  /** @deprecated use encoder private options instead */
2452 #endif
2453 
2454 #if FF_API_PRIVATE_OPT
2455  /** @deprecated use encoder private options instead */
2458 
2459  /** @deprecated use encoder private options instead */
2462 
2463  /** @deprecated use encoder private options instead */
2466 
2467  /** @deprecated use encoder private options instead */
2470 #endif /* FF_API_PRIVATE_OPT */
2471 
2472  /**
2473  * trellis RD quantization
2474  * - encoding: Set by user.
2475  * - decoding: unused
2476  */
2477  int trellis;
2478 
2479 #if FF_API_PRIVATE_OPT
2480  /** @deprecated use encoder private options instead */
2483 
2484  /** @deprecated use encoder private options instead */
2487 
2488  /** @deprecated use encoder private options instead */
2491 #endif
2492 
2493 #if FF_API_RTP_CALLBACK
2494  /**
2495  * @deprecated unused
2496  */
2497  /* The RTP callback: This function is called */
2498  /* every time the encoder has a packet to send. */
2499  /* It depends on the encoder if the data starts */
2500  /* with a Start Code (it should). H.263 does. */
2501  /* mb_nb contains the number of macroblocks */
2502  /* encoded in the RTP payload. */
2504  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2505 #endif
2506 
2507 #if FF_API_PRIVATE_OPT
2508  /** @deprecated use encoder private options instead */
2510  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2511  /* do its best to deliver a chunk with size */
2512  /* below rtp_payload_size, the chunk will start */
2513  /* with a start code on some codecs like H.263. */
2514  /* This doesn't take account of any particular */
2515  /* headers inside the transmitted RTP payload. */
2516 #endif
2517 
2518 #if FF_API_STAT_BITS
2519  /* statistics, used for 2-pass encoding */
2521  int mv_bits;
2529  int i_count;
2531  int p_count;
2536 
2537  /** @deprecated this field is unused */
2540 #endif
2541 
2542  /**
2543  * pass1 encoding statistics output buffer
2544  * - encoding: Set by libavcodec.
2545  * - decoding: unused
2546  */
2547  char *stats_out;
2548 
2549  /**
2550  * pass2 encoding statistics input buffer
2551  * Concatenated stuff from stats_out of pass1 should be placed here.
2552  * - encoding: Allocated/set/freed by user.
2553  * - decoding: unused
2554  */
2555  char *stats_in;
2556 
2557  /**
2558  * Work around bugs in encoders which sometimes cannot be detected automatically.
2559  * - encoding: Set by user
2560  * - decoding: Set by user
2561  */
2563 #define FF_BUG_AUTODETECT 1 ///< autodetection
2564 #define FF_BUG_XVID_ILACE 4
2565 #define FF_BUG_UMP4 8
2566 #define FF_BUG_NO_PADDING 16
2567 #define FF_BUG_AMV 32
2568 #define FF_BUG_QPEL_CHROMA 64
2569 #define FF_BUG_STD_QPEL 128
2570 #define FF_BUG_QPEL_CHROMA2 256
2571 #define FF_BUG_DIRECT_BLOCKSIZE 512
2572 #define FF_BUG_EDGE 1024
2573 #define FF_BUG_HPEL_CHROMA 2048
2574 #define FF_BUG_DC_CLIP 4096
2575 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2576 #define FF_BUG_TRUNCATED 16384
2577 #define FF_BUG_IEDGE 32768
2578 
2579  /**
2580  * strictly follow the standard (MPEG-4, ...).
2581  * - encoding: Set by user.
2582  * - decoding: Set by user.
2583  * Setting this to STRICT or higher means the encoder and decoder will
2584  * generally do stupid things, whereas setting it to unofficial or lower
2585  * will mean the encoder might produce output that is not supported by all
2586  * spec-compliant decoders. Decoders don't differentiate between normal,
2587  * unofficial and experimental (that is, they always try to decode things
2588  * when they can) unless they are explicitly asked to behave stupidly
2589  * (=strictly conform to the specs)
2590  */
2592 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2593 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2594 #define FF_COMPLIANCE_NORMAL 0
2595 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2596 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2597 
2598  /**
2599  * error concealment flags
2600  * - encoding: unused
2601  * - decoding: Set by user.
2602  */
2604 #define FF_EC_GUESS_MVS 1
2605 #define FF_EC_DEBLOCK 2
2606 #define FF_EC_FAVOR_INTER 256
2607 
2608  /**
2609  * debug
2610  * - encoding: Set by user.
2611  * - decoding: Set by user.
2612  */
2613  int debug;
2614 #define FF_DEBUG_PICT_INFO 1
2615 #define FF_DEBUG_RC 2
2616 #define FF_DEBUG_BITSTREAM 4
2617 #define FF_DEBUG_MB_TYPE 8
2618 #define FF_DEBUG_QP 16
2619 #if FF_API_DEBUG_MV
2620 /**
2621  * @deprecated this option does nothing
2622  */
2623 #define FF_DEBUG_MV 32
2624 #endif
2625 #define FF_DEBUG_DCT_COEFF 0x00000040
2626 #define FF_DEBUG_SKIP 0x00000080
2627 #define FF_DEBUG_STARTCODE 0x00000100
2628 #define FF_DEBUG_ER 0x00000400
2629 #define FF_DEBUG_MMCO 0x00000800
2630 #define FF_DEBUG_BUGS 0x00001000
2631 #if FF_API_DEBUG_MV
2632 #define FF_DEBUG_VIS_QP 0x00002000
2633 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2634 #endif
2635 #define FF_DEBUG_BUFFERS 0x00008000
2636 #define FF_DEBUG_THREADS 0x00010000
2637 #define FF_DEBUG_GREEN_MD 0x00800000
2638 #define FF_DEBUG_NOMC 0x01000000
2639 
2640 #if FF_API_DEBUG_MV
2641  /**
2642  * debug
2643  * - encoding: Set by user.
2644  * - decoding: Set by user.
2645  */
2646  int debug_mv;
2647 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2648 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2649 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2650 #endif
2651 
2652  /**
2653  * Error recognition; may misdetect some more or less valid parts as errors.
2654  * - encoding: unused
2655  * - decoding: Set by user.
2656  */
2658 
2659 /**
2660  * Verify checksums embedded in the bitstream (could be of either encoded or
2661  * decoded data, depending on the codec) and print an error message on mismatch.
2662  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2663  * decoder returning an error.
2664  */
2665 #define AV_EF_CRCCHECK (1<<0)
2666 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2667 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2668 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2669 
2670 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2671 #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
2672 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2673 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2674 
2675 
2676  /**
2677  * opaque 64-bit number (generally a PTS) that will be reordered and
2678  * output in AVFrame.reordered_opaque
2679  * - encoding: unused
2680  * - decoding: Set by user.
2681  */
2683 
2684  /**
2685  * Hardware accelerator in use
2686  * - encoding: unused.
2687  * - decoding: Set by libavcodec
2688  */
2689  const struct AVHWAccel *hwaccel;
2690 
2691  /**
2692  * Hardware accelerator context.
2693  * For some hardware accelerators, a global context needs to be
2694  * provided by the user. In that case, this holds display-dependent
2695  * data FFmpeg cannot instantiate itself. Please refer to the
2696  * FFmpeg HW accelerator documentation to know how to fill this
2697  * is. e.g. for VA API, this is a struct vaapi_context.
2698  * - encoding: unused
2699  * - decoding: Set by user
2700  */
2702 
2703  /**
2704  * error
2705  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2706  * - decoding: unused
2707  */
2709 
2710  /**
2711  * DCT algorithm, see FF_DCT_* below
2712  * - encoding: Set by user.
2713  * - decoding: unused
2714  */
2716 #define FF_DCT_AUTO 0
2717 #define FF_DCT_FASTINT 1
2718 #define FF_DCT_INT 2
2719 #define FF_DCT_MMX 3
2720 #define FF_DCT_ALTIVEC 5
2721 #define FF_DCT_FAAN 6
2722 
2723  /**
2724  * IDCT algorithm, see FF_IDCT_* below.
2725  * - encoding: Set by user.
2726  * - decoding: Set by user.
2727  */
2729 #define FF_IDCT_AUTO 0
2730 #define FF_IDCT_INT 1
2731 #define FF_IDCT_SIMPLE 2
2732 #define FF_IDCT_SIMPLEMMX 3
2733 #define FF_IDCT_ARM 7
2734 #define FF_IDCT_ALTIVEC 8
2735 #define FF_IDCT_SIMPLEARM 10
2736 #define FF_IDCT_XVID 14
2737 #define FF_IDCT_SIMPLEARMV5TE 16
2738 #define FF_IDCT_SIMPLEARMV6 17
2739 #define FF_IDCT_FAAN 20
2740 #define FF_IDCT_SIMPLENEON 22
2741 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2742 #define FF_IDCT_SIMPLEAUTO 128
2743 
2744  /**
2745  * bits per sample/pixel from the demuxer (needed for huffyuv).
2746  * - encoding: Set by libavcodec.
2747  * - decoding: Set by user.
2748  */
2750 
2751  /**
2752  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2753  * - encoding: set by user.
2754  * - decoding: set by libavcodec.
2755  */
2757 
2758 #if FF_API_LOWRES
2759  /**
2760  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2761  * - encoding: unused
2762  * - decoding: Set by user.
2763  */
2764  int lowres;
2765 #endif
2766 
2767 #if FF_API_CODED_FRAME
2768  /**
2769  * the picture in the bitstream
2770  * - encoding: Set by libavcodec.
2771  * - decoding: unused
2772  *
2773  * @deprecated use the quality factor packet side data instead
2774  */
2776 #endif
2777 
2778  /**
2779  * thread count
2780  * is used to decide how many independent tasks should be passed to execute()
2781  * - encoding: Set by user.
2782  * - decoding: Set by user.
2783  */
2785 
2786  /**
2787  * Which multithreading methods to use.
2788  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2789  * so clients which cannot provide future frames should not use it.
2790  *
2791  * - encoding: Set by user, otherwise the default is used.
2792  * - decoding: Set by user, otherwise the default is used.
2793  */
2795 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2796 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2797 
2798  /**
2799  * Which multithreading methods are in use by the codec.
2800  * - encoding: Set by libavcodec.
2801  * - decoding: Set by libavcodec.
2802  */
2804 
2805  /**
2806  * Set by the client if its custom get_buffer() callback can be called
2807  * synchronously from another thread, which allows faster multithreaded decoding.
2808  * draw_horiz_band() will be called from other threads regardless of this setting.
2809  * Ignored if the default get_buffer() is used.
2810  * - encoding: Set by user.
2811  * - decoding: Set by user.
2812  */
2814 
2815  /**
2816  * The codec may call this to execute several independent things.
2817  * It will return only after finishing all tasks.
2818  * The user may replace this with some multithreaded implementation,
2819  * the default implementation will execute the parts serially.
2820  * @param count the number of things to execute
2821  * - encoding: Set by libavcodec, user can override.
2822  * - decoding: Set by libavcodec, user can override.
2823  */
2824  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2825 
2826  /**
2827  * The codec may call this to execute several independent things.
2828  * It will return only after finishing all tasks.
2829  * The user may replace this with some multithreaded implementation,
2830  * the default implementation will execute the parts serially.
2831  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2832  * @param c context passed also to func
2833  * @param count the number of things to execute
2834  * @param arg2 argument passed unchanged to func
2835  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2836  * @param func function that will be called count times, with jobnr from 0 to count-1.
2837  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2838  * two instances of func executing at the same time will have the same threadnr.
2839  * @return always 0 currently, but code should handle a future improvement where when any call to func
2840  * returns < 0 no further calls to func may be done and < 0 is returned.
2841  * - encoding: Set by libavcodec, user can override.
2842  * - decoding: Set by libavcodec, user can override.
2843  */
2844  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2845 
2846  /**
2847  * noise vs. sse weight for the nsse comparison function
2848  * - encoding: Set by user.
2849  * - decoding: unused
2850  */
2852 
2853  /**
2854  * profile
2855  * - encoding: Set by user.
2856  * - decoding: Set by libavcodec.
2857  */
2858  int profile;
2859 #define FF_PROFILE_UNKNOWN -99
2860 #define FF_PROFILE_RESERVED -100
2861 
2862 #define FF_PROFILE_AAC_MAIN 0
2863 #define FF_PROFILE_AAC_LOW 1
2864 #define FF_PROFILE_AAC_SSR 2
2865 #define FF_PROFILE_AAC_LTP 3
2866 #define FF_PROFILE_AAC_HE 4
2867 #define FF_PROFILE_AAC_HE_V2 28
2868 #define FF_PROFILE_AAC_LD 22
2869 #define FF_PROFILE_AAC_ELD 38
2870 #define FF_PROFILE_MPEG2_AAC_LOW 128
2871 #define FF_PROFILE_MPEG2_AAC_HE 131
2872 
2873 #define FF_PROFILE_DNXHD 0
2874 #define FF_PROFILE_DNXHR_LB 1
2875 #define FF_PROFILE_DNXHR_SQ 2
2876 #define FF_PROFILE_DNXHR_HQ 3
2877 #define FF_PROFILE_DNXHR_HQX 4
2878 #define FF_PROFILE_DNXHR_444 5
2879 
2880 #define FF_PROFILE_DTS 20
2881 #define FF_PROFILE_DTS_ES 30
2882 #define FF_PROFILE_DTS_96_24 40
2883 #define FF_PROFILE_DTS_HD_HRA 50
2884 #define FF_PROFILE_DTS_HD_MA 60
2885 #define FF_PROFILE_DTS_EXPRESS 70
2886 
2887 #define FF_PROFILE_MPEG2_422 0
2888 #define FF_PROFILE_MPEG2_HIGH 1
2889 #define FF_PROFILE_MPEG2_SS 2
2890 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2891 #define FF_PROFILE_MPEG2_MAIN 4
2892 #define FF_PROFILE_MPEG2_SIMPLE 5
2893 
2894 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2895 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2896 
2897 #define FF_PROFILE_H264_BASELINE 66
2898 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2899 #define FF_PROFILE_H264_MAIN 77
2900 #define FF_PROFILE_H264_EXTENDED 88
2901 #define FF_PROFILE_H264_HIGH 100
2902 #define FF_PROFILE_H264_HIGH_10 110
2903 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2904 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2905 #define FF_PROFILE_H264_HIGH_422 122
2906 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2907 #define FF_PROFILE_H264_STEREO_HIGH 128
2908 #define FF_PROFILE_H264_HIGH_444 144
2909 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2910 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2911 #define FF_PROFILE_H264_CAVLC_444 44
2912 
2913 #define FF_PROFILE_VC1_SIMPLE 0
2914 #define FF_PROFILE_VC1_MAIN 1
2915 #define FF_PROFILE_VC1_COMPLEX 2
2916 #define FF_PROFILE_VC1_ADVANCED 3
2917 
2918 #define FF_PROFILE_MPEG4_SIMPLE 0
2919 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2920 #define FF_PROFILE_MPEG4_CORE 2
2921 #define FF_PROFILE_MPEG4_MAIN 3
2922 #define FF_PROFILE_MPEG4_N_BIT 4
2923 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2924 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2925 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2926 #define FF_PROFILE_MPEG4_HYBRID 8
2927 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2928 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2929 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2930 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2931 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2932 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2933 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2934 
2935 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2936 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2937 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2938 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2939 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2940 
2941 #define FF_PROFILE_VP9_0 0
2942 #define FF_PROFILE_VP9_1 1
2943 #define FF_PROFILE_VP9_2 2
2944 #define FF_PROFILE_VP9_3 3
2945 
2946 #define FF_PROFILE_HEVC_MAIN 1
2947 #define FF_PROFILE_HEVC_MAIN_10 2
2948 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2949 #define FF_PROFILE_HEVC_REXT 4
2950 
2951 #define FF_PROFILE_AV1_MAIN 0
2952 #define FF_PROFILE_AV1_HIGH 1
2953 #define FF_PROFILE_AV1_PROFESSIONAL 2
2954 
2955 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2956 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
2957 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
2958 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
2959 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
2960 
2961 #define FF_PROFILE_SBC_MSBC 1
2962 
2963  /**
2964  * level
2965  * - encoding: Set by user.
2966  * - decoding: Set by libavcodec.
2967  */
2968  int level;
2969 #define FF_LEVEL_UNKNOWN -99
2970 
2971  /**
2972  * Skip loop filtering for selected frames.
2973  * - encoding: unused
2974  * - decoding: Set by user.
2975  */
2977 
2978  /**
2979  * Skip IDCT/dequantization for selected frames.
2980  * - encoding: unused
2981  * - decoding: Set by user.
2982  */
2984 
2985  /**
2986  * Skip decoding for selected frames.
2987  * - encoding: unused
2988  * - decoding: Set by user.
2989  */
2991 
2992  /**
2993  * Header containing style information for text subtitles.
2994  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2995  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2996  * the Format line following. It shouldn't include any Dialogue line.
2997  * - encoding: Set/allocated/freed by user (before avcodec_open2())
2998  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2999  */
3002 
3003 #if FF_API_VBV_DELAY
3004  /**
3005  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3006  * Used for compliant TS muxing.
3007  * - encoding: Set by libavcodec.
3008  * - decoding: unused.
3009  * @deprecated this value is now exported as a part of
3010  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3011  */
3013  uint64_t vbv_delay;
3014 #endif
3015 
3016 #if FF_API_SIDEDATA_ONLY_PKT
3017  /**
3018  * Encoding only and set by default. Allow encoders to output packets
3019  * that do not contain any encoded data, only side data.
3020  *
3021  * Some encoders need to output such packets, e.g. to update some stream
3022  * parameters at the end of encoding.
3023  *
3024  * @deprecated this field disables the default behaviour and
3025  * it is kept only for compatibility.
3026  */
3029 #endif
3030 
3031  /**
3032  * Audio only. The number of "priming" samples (padding) inserted by the
3033  * encoder at the beginning of the audio. I.e. this number of leading
3034  * decoded samples must be discarded by the caller to get the original audio
3035  * without leading padding.
3036  *
3037  * - decoding: unused
3038  * - encoding: Set by libavcodec. The timestamps on the output packets are
3039  * adjusted by the encoder so that they always refer to the
3040  * first sample of the data actually contained in the packet,
3041  * including any added padding. E.g. if the timebase is
3042  * 1/samplerate and the timestamp of the first input sample is
3043  * 0, the timestamp of the first output packet will be
3044  * -initial_padding.
3045  */
3047 
3048  /**
3049  * - decoding: For codecs that store a framerate value in the compressed
3050  * bitstream, the decoder may export it here. { 0, 1} when
3051  * unknown.
3052  * - encoding: May be used to signal the framerate of CFR content to an
3053  * encoder.
3054  */
3056 
3057  /**
3058  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3059  * - encoding: unused.
3060  * - decoding: Set by libavcodec before calling get_format()
3061  */
3063 
3064  /**
3065  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3066  * - encoding unused.
3067  * - decoding set by user.
3068  */
3070 
3071  /**
3072  * AVCodecDescriptor
3073  * - encoding: unused.
3074  * - decoding: set by libavcodec.
3075  */
3077 
3078 #if !FF_API_LOWRES
3079  /**
3080  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3081  * - encoding: unused
3082  * - decoding: Set by user.
3083  */
3084  int lowres;
3085 #endif
3086 
3087  /**
3088  * Current statistics for PTS correction.
3089  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3090  * - encoding: unused
3091  */
3092  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3093  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3094  int64_t pts_correction_last_pts; /// PTS of the last frame
3095  int64_t pts_correction_last_dts; /// DTS of the last frame
3096 
3097  /**
3098  * Character encoding of the input subtitles file.
3099  * - decoding: set by user
3100  * - encoding: unused
3101  */
3103 
3104  /**
3105  * Subtitles character encoding mode. Formats or codecs might be adjusting
3106  * this setting (if they are doing the conversion themselves for instance).
3107  * - decoding: set by libavcodec
3108  * - encoding: unused
3109  */
3111 #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)
3112 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3113 #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
3114 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
3115 
3116  /**
3117  * Skip processing alpha if supported by codec.
3118  * Note that if the format uses pre-multiplied alpha (common with VP6,
3119  * and recommended due to better video quality/compression)
3120  * the image will look as if alpha-blended onto a black background.
3121  * However for formats that do not use pre-multiplied alpha
3122  * there might be serious artefacts (though e.g. libswscale currently
3123  * assumes pre-multiplied alpha anyway).
3124  *
3125  * - decoding: set by user
3126  * - encoding: unused
3127  */
3129 
3130  /**
3131  * Number of samples to skip after a discontinuity
3132  * - decoding: unused
3133  * - encoding: set by libavcodec
3134  */
3136 
3137 #if !FF_API_DEBUG_MV
3138  /**
3139  * debug motion vectors
3140  * - encoding: Set by user.
3141  * - decoding: Set by user.
3142  */
3144 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3145 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3146 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3147 #endif
3148 
3149  /**
3150  * custom intra quantization matrix
3151  * - encoding: Set by user, can be NULL.
3152  * - decoding: unused.
3153  */
3155 
3156  /**
3157  * dump format separator.
3158  * can be ", " or "\n " or anything else
3159  * - encoding: Set by user.
3160  * - decoding: Set by user.
3161  */
3163 
3164  /**
3165  * ',' separated list of allowed decoders.
3166  * If NULL then all are allowed
3167  * - encoding: unused
3168  * - decoding: set by user
3169  */
3171 
3172  /**
3173  * Properties of the stream that gets decoded
3174  * - encoding: unused
3175  * - decoding: set by libavcodec
3176  */
3177  unsigned properties;
3178 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3179 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3180 
3181  /**
3182  * Additional data associated with the entire coded stream.
3183  *
3184  * - decoding: unused
3185  * - encoding: may be set by libavcodec after avcodec_open2().
3186  */
3189 
3190  /**
3191  * A reference to the AVHWFramesContext describing the input (for encoding)
3192  * or output (decoding) frames. The reference is set by the caller and
3193  * afterwards owned (and freed) by libavcodec - it should never be read by
3194  * the caller after being set.
3195  *
3196  * - decoding: This field should be set by the caller from the get_format()
3197  * callback. The previous reference (if any) will always be
3198  * unreffed by libavcodec before the get_format() call.
3199  *
3200  * If the default get_buffer2() is used with a hwaccel pixel
3201  * format, then this AVHWFramesContext will be used for
3202  * allocating the frame buffers.
3203  *
3204  * - encoding: For hardware encoders configured to use a hwaccel pixel
3205  * format, this field should be set by the caller to a reference
3206  * to the AVHWFramesContext describing input frames.
3207  * AVHWFramesContext.format must be equal to
3208  * AVCodecContext.pix_fmt.
3209  *
3210  * This field should be set before avcodec_open2() is called.
3211  */
3213 
3214  /**
3215  * Control the form of AVSubtitle.rects[N]->ass
3216  * - decoding: set by user
3217  * - encoding: unused
3218  */
3220 #define FF_SUB_TEXT_FMT_ASS 0
3221 #if FF_API_ASS_TIMING
3222 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3223 #endif
3224 
3225  /**
3226  * Audio only. The amount of padding (in samples) appended by the encoder to
3227  * the end of the audio. I.e. this number of decoded samples must be
3228  * discarded by the caller from the end of the stream to get the original
3229  * audio without any trailing padding.
3230  *
3231  * - decoding: unused
3232  * - encoding: unused
3233  */
3235 
3236  /**
3237  * The number of pixels per image to maximally accept.
3238  *
3239  * - decoding: set by user
3240  * - encoding: set by user
3241  */
3242  int64_t max_pixels;
3243 
3244  /**
3245  * A reference to the AVHWDeviceContext describing the device which will
3246  * be used by a hardware encoder/decoder. The reference is set by the
3247  * caller and afterwards owned (and freed) by libavcodec.
3248  *
3249  * This should be used if either the codec device does not require
3250  * hardware frames or any that are used are to be allocated internally by
3251  * libavcodec. If the user wishes to supply any of the frames used as
3252  * encoder input or decoder output then hw_frames_ctx should be used
3253  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3254  * field will be ignored while decoding the associated stream segment, but
3255  * may again be used on a following one after another get_format() call.
3256  *
3257  * For both encoders and decoders this field should be set before
3258  * avcodec_open2() is called and must not be written to thereafter.
3259  *
3260  * Note that some decoders may require this field to be set initially in
3261  * order to support hw_frames_ctx at all - in that case, all frames
3262  * contexts used must be created on the same device.
3263  */
3265 
3266  /**
3267  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3268  * decoding (if active).
3269  * - encoding: unused
3270  * - decoding: Set by user (either before avcodec_open2(), or in the
3271  * AVCodecContext.get_format callback)
3272  */
3274 
3275  /**
3276  * Video decoding only. Certain video codecs support cropping, meaning that
3277  * only a sub-rectangle of the decoded frame is intended for display. This
3278  * option controls how cropping is handled by libavcodec.
3279  *
3280  * When set to 1 (the default), libavcodec will apply cropping internally.
3281  * I.e. it will modify the output frame width/height fields and offset the
3282  * data pointers (only by as much as possible while preserving alignment, or
3283  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3284  * the frames output by the decoder refer only to the cropped area. The
3285  * crop_* fields of the output frames will be zero.
3286  *
3287  * When set to 0, the width/height fields of the output frames will be set
3288  * to the coded dimensions and the crop_* fields will describe the cropping
3289  * rectangle. Applying the cropping is left to the caller.
3290  *
3291  * @warning When hardware acceleration with opaque output frames is used,
3292  * libavcodec is unable to apply cropping from the top/left border.
3293  *
3294  * @note when this option is set to zero, the width/height fields of the
3295  * AVCodecContext and output AVFrames have different meanings. The codec
3296  * context fields store display dimensions (with the coded dimensions in
3297  * coded_width/height), while the frame fields store the coded dimensions
3298  * (with the display dimensions being determined by the crop_* fields).
3299  */
3301 
3302  /*
3303  * Video decoding only. Sets the number of extra hardware frames which
3304  * the decoder will allocate for use by the caller. This must be set
3305  * before avcodec_open2() is called.
3306  *
3307  * Some hardware decoders require all frames that they will use for
3308  * output to be defined in advance before decoding starts. For such
3309  * decoders, the hardware frame pool must therefore be of a fixed size.
3310  * The extra frames set here are on top of any number that the decoder
3311  * needs internally in order to operate normally (for example, frames
3312  * used as reference pictures).
3313  */
3315 } AVCodecContext;
3316 
3317 #if FF_API_CODEC_GET_SET
3318 /**
3319  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3320  * compatibility, and do not need to be used anymore.
3321  */
3326 
3331 
3333 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3334 
3335 #if FF_API_LOWRES
3337 int av_codec_get_lowres(const AVCodecContext *avctx);
3339 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3340 #endif
3341 
3343 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3345 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3346 
3348 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3350 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3351 #endif
3352 
3353 /**
3354  * AVProfile.
3355  */
3356 typedef struct AVProfile {
3357  int profile;
3358  const char *name; ///< short name for the profile
3359 } AVProfile;
3360 
3361 enum {
3362  /**
3363  * The codec supports this format via the hw_device_ctx interface.
3364  *
3365  * When selecting this format, AVCodecContext.hw_device_ctx should
3366  * have been set to a device of the specified type before calling
3367  * avcodec_open2().
3368  */
3370  /**
3371  * The codec supports this format via the hw_frames_ctx interface.
3372  *
3373  * When selecting this format for a decoder,
3374  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3375  * context inside the get_format() callback. The frames context
3376  * must have been created on a device of the specified type.
3377  */
3379  /**
3380  * The codec supports this format by some internal method.
3381  *
3382  * This format can be selected without any additional configuration -
3383  * no device or frames context is required.
3384  */
3386  /**
3387  * The codec supports this format by some ad-hoc method.
3388  *
3389  * Additional settings and/or function calls are required. See the
3390  * codec-specific documentation for details. (Methods requiring
3391  * this sort of configuration are deprecated and others should be
3392  * used in preference.)
3393  */
3395 };
3396 
3397 typedef struct AVCodecHWConfig {
3398  /**
3399  * A hardware pixel format which the codec can use.
3400  */
3402  /**
3403  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3404  * setup methods which can be used with this configuration.
3405  */
3406  int methods;
3407  /**
3408  * The device type associated with the configuration.
3409  *
3410  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3411  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3412  */
3414 } AVCodecHWConfig;
3415 
3416 typedef struct AVCodecDefault AVCodecDefault;
3417 
3418 struct AVSubtitle;
3419 
3420 /**
3421  * AVCodec.
3422  */
3423 typedef struct AVCodec {
3424  /**
3425  * Name of the codec implementation.
3426  * The name is globally unique among encoders and among decoders (but an
3427  * encoder and a decoder can share the same name).
3428  * This is the primary way to find a codec from the user perspective.
3429  */
3430  const char *name;
3431  /**
3432  * Descriptive name for the codec, meant to be more human readable than name.
3433  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3434  */
3435  const char *long_name;
3438  /**
3439  * Codec capabilities.
3440  * see AV_CODEC_CAP_*
3441  */
3443  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3444  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3445  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3446  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3447  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3448  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3449  const AVClass *priv_class; ///< AVClass for the private context
3450  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3451 
3452  /**
3453  * Group name of the codec implementation.
3454  * This is a short symbolic name of the wrapper backing this codec. A
3455  * wrapper uses some kind of external implementation for the codec, such
3456  * as an external library, or a codec implementation provided by the OS or
3457  * the hardware.
3458  * If this field is NULL, this is a builtin, libavcodec native codec.
3459  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3460  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3461  */
3462  const char *wrapper_name;
3463 
3464  /*****************************************************************
3465  * No fields below this line are part of the public API. They
3466  * may not be used outside of libavcodec and can be changed and
3467  * removed at will.
3468  * New public fields should be added right above.
3469  *****************************************************************
3470  */
3472  struct AVCodec *next;
3473  /**
3474  * @name Frame-level threading support functions
3475  * @{
3476  */
3477  /**
3478  * If defined, called on thread contexts when they are created.
3479  * If the codec allocates writable tables in init(), re-allocate them here.
3480  * priv_data will be set to a copy of the original.
3481  */
3483  /**
3484  * Copy necessary context variables from a previous thread context to the current one.
3485  * If not defined, the next thread will start automatically; otherwise, the codec
3486  * must call ff_thread_finish_setup().
3487  *
3488  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3489  */
3491  /** @} */
3492 
3493  /**
3494  * Private codec-specific defaults.
3495  */
3497 
3498  /**
3499  * Initialize codec static data, called from avcodec_register().
3500  *
3501  * This is not intended for time consuming operations as it is
3502  * run for every codec regardless of that codec being used.
3503  */
3504  void (*init_static_data)(struct AVCodec *codec);
3505 
3507  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3508  const struct AVSubtitle *sub);
3509  /**
3510  * Encode data to an AVPacket.
3511  *
3512  * @param avctx codec context
3513  * @param avpkt output AVPacket (may contain a user-provided buffer)
3514  * @param[in] frame AVFrame containing the raw data to be encoded
3515  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3516  * non-empty packet was returned in avpkt.
3517  * @return 0 on success, negative error code on failure
3518  */
3519  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3520  int *got_packet_ptr);
3521  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3523  /**
3524  * Encode API with decoupled packet/frame dataflow. The API is the
3525  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3526  * that:
3527  * - never called if the codec is closed or the wrong type,
3528  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3529  * - only one drain frame is ever passed down,
3530  */
3533 
3534  /**
3535  * Decode API with decoupled packet/frame dataflow. This function is called
3536  * to get one output frame. It should call ff_decode_get_packet() to obtain
3537  * input data.
3538  */
3540  /**
3541  * Flush buffers.
3542  * Will be called when seeking
3543  */
3545  /**
3546  * Internal codec capabilities.
3547  * See FF_CODEC_CAP_* in internal.h
3548  */
3550 
3551  /**
3552  * Decoding only, a comma-separated list of bitstream filters to apply to
3553  * packets before decoding.
3554  */
3555  const char *bsfs;
3556 
3557  /**
3558  * Array of pointers to hardware configurations supported by the codec,
3559  * or NULL if no hardware supported. The array is terminated by a NULL
3560  * pointer.
3561  *
3562  * The user can only access this field via avcodec_get_hw_config().
3563  */
3565 } AVCodec;
3566 
3567 #if FF_API_CODEC_GET_SET
3569 int av_codec_get_max_lowres(const AVCodec *codec);
3570 #endif
3571 
3572 struct MpegEncContext;
3573 
3574 /**
3575  * Retrieve supported hardware configurations for a codec.
3576  *
3577  * Values of index from zero to some maximum return the indexed configuration
3578  * descriptor; all other values return NULL. If the codec does not support
3579  * any hardware configurations then it will always return NULL.
3580  */
3581 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3582 
3583 /**
3584  * @defgroup lavc_hwaccel AVHWAccel
3585  *
3586  * @note Nothing in this structure should be accessed by the user. At some
3587  * point in future it will not be externally visible at all.
3588  *
3589  * @{
3590  */
3591 typedef struct AVHWAccel {
3592  /**
3593  * Name of the hardware accelerated codec.
3594  * The name is globally unique among encoders and among decoders (but an
3595  * encoder and a decoder can share the same name).
3596  */
3597  const char *name;
3598 
3599  /**
3600  * Type of codec implemented by the hardware accelerator.
3601  *
3602  * See AVMEDIA_TYPE_xxx
3603  */
3605 
3606  /**
3607  * Codec implemented by the hardware accelerator.
3608  *
3609  * See AV_CODEC_ID_xxx
3610  */
3612 
3613  /**
3614  * Supported pixel format.
3615  *
3616  * Only hardware accelerated formats are supported here.
3617  */
3619 
3620  /**
3621  * Hardware accelerated codec capabilities.
3622  * see AV_HWACCEL_CODEC_CAP_*
3623  */
3625 
3626  /*****************************************************************
3627  * No fields below this line are part of the public API. They
3628  * may not be used outside of libavcodec and can be changed and
3629  * removed at will.
3630  * New public fields should be added right above.
3631  *****************************************************************
3632  */
3633 
3634  /**
3635  * Allocate a custom buffer
3636  */
3638 
3639  /**
3640  * Called at the beginning of each frame or field picture.
3641  *
3642  * Meaningful frame information (codec specific) is guaranteed to
3643  * be parsed at this point. This function is mandatory.
3644  *
3645  * Note that buf can be NULL along with buf_size set to 0.
3646  * Otherwise, this means the whole frame is available at this point.
3647  *
3648  * @param avctx the codec context
3649  * @param buf the frame data buffer base
3650  * @param buf_size the size of the frame in bytes
3651  * @return zero if successful, a negative value otherwise
3652  */
3653  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3654 
3655  /**
3656  * Callback for parameter data (SPS/PPS/VPS etc).
3657  *
3658  * Useful for hardware decoders which keep persistent state about the
3659  * video parameters, and need to receive any changes to update that state.
3660  *
3661  * @param avctx the codec context
3662  * @param type the nal unit type
3663  * @param buf the nal unit data buffer
3664  * @param buf_size the size of the nal unit in bytes
3665  * @return zero if successful, a negative value otherwise
3666  */
3667  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3668 
3669  /**
3670  * Callback for each slice.
3671  *
3672  * Meaningful slice information (codec specific) is guaranteed to
3673  * be parsed at this point. This function is mandatory.
3674  * The only exception is XvMC, that works on MB level.
3675  *
3676  * @param avctx the codec context
3677  * @param buf the slice data buffer base
3678  * @param buf_size the size of the slice in bytes
3679  * @return zero if successful, a negative value otherwise
3680  */
3681  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3682 
3683  /**
3684  * Called at the end of each frame or field picture.
3685  *
3686  * The whole picture is parsed at this point and can now be sent
3687  * to the hardware accelerator. This function is mandatory.
3688  *
3689  * @param avctx the codec context
3690  * @return zero if successful, a negative value otherwise
3691  */
3693 
3694  /**
3695  * Size of per-frame hardware accelerator private data.
3696  *
3697  * Private data is allocated with av_mallocz() before
3698  * AVCodecContext.get_buffer() and deallocated after
3699  * AVCodecContext.release_buffer().
3700  */
3702 
3703  /**
3704  * Called for every Macroblock in a slice.
3705  *
3706  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3707  * Instead of decoding to raw picture, MB parameters are
3708  * stored in an array provided by the video driver.
3709  *
3710  * @param s the mpeg context
3711  */
3713 
3714  /**
3715  * Initialize the hwaccel private data.
3716  *
3717  * This will be called from ff_get_format(), after hwaccel and
3718  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3719  * is allocated.
3720  */
3722 
3723  /**
3724  * Uninitialize the hwaccel private data.
3725  *
3726  * This will be called from get_format() or avcodec_close(), after hwaccel
3727  * and hwaccel_context are already uninitialized.
3728  */
3730 
3731  /**
3732  * Size of the private data to allocate in
3733  * AVCodecInternal.hwaccel_priv_data.
3734  */
3736 
3737  /**
3738  * Internal hwaccel capabilities.
3739  */
3741 
3742  /**
3743  * Fill the given hw_frames context with current codec parameters. Called
3744  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3745  * details.
3746  *
3747  * This CAN be called before AVHWAccel.init is called, and you must assume
3748  * that avctx->hwaccel_priv_data is invalid.
3749  */
3751 } AVHWAccel;
3752 
3753 /**
3754  * HWAccel is experimental and is thus avoided in favor of non experimental
3755  * codecs
3756  */
3757 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3758 
3759 /**
3760  * Hardware acceleration should be used for decoding even if the codec level
3761  * used is unknown or higher than the maximum supported level reported by the
3762  * hardware driver.
3763  *
3764  * It's generally a good idea to pass this flag unless you have a specific
3765  * reason not to, as hardware tends to under-report supported levels.
3766  */
3767 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3768 
3769 /**
3770  * Hardware acceleration can output YUV pixel formats with a different chroma
3771  * sampling than 4:2:0 and/or other than 8 bits per component.
3772  */
3773 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3774 
3775 /**
3776  * Hardware acceleration should still be attempted for decoding when the
3777  * codec profile does not match the reported capabilities of the hardware.
3778  *
3779  * For example, this can be used to try to decode baseline profile H.264
3780  * streams in hardware - it will often succeed, because many streams marked
3781  * as baseline profile actually conform to constrained baseline profile.
3782  *
3783  * @warning If the stream is actually not supported then the behaviour is
3784  * undefined, and may include returning entirely incorrect output
3785  * while indicating success.
3786  */
3787 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3788 
3789 /**
3790  * @}
3791  */
3792 
3793 #if FF_API_AVPICTURE
3794 /**
3795  * @defgroup lavc_picture AVPicture
3796  *
3797  * Functions for working with AVPicture
3798  * @{
3799  */
3800 
3801 /**
3802  * Picture data structure.
3803  *
3804  * Up to four components can be stored into it, the last component is
3805  * alpha.
3806  * @deprecated use AVFrame or imgutils functions instead
3807  */
3808 typedef struct AVPicture {
3810  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3812  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3813 } AVPicture;
3814 
3815 /**
3816  * @}
3817  */
3818 #endif
3819 
3822 
3823  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3824 
3825  /**
3826  * Plain text, the text field must be set by the decoder and is
3827  * authoritative. ass and pict fields may contain approximations.
3828  */
3830 
3831  /**
3832  * Formatted text, the ass field must be set by the decoder and is
3833  * authoritative. pict and text fields may contain approximations.
3834  */
3836 };
3837 
3838 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3839 
3840 typedef struct AVSubtitleRect {
3841  int x; ///< top left corner of pict, undefined when pict is not set
3842  int y; ///< top left corner of pict, undefined when pict is not set
3843  int w; ///< width of pict, undefined when pict is not set
3844  int h; ///< height of pict, undefined when pict is not set
3845  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3846 
3847 #if FF_API_AVPICTURE
3848  /**
3849  * @deprecated unused
3850  */
3853 #endif
3854  /**
3855  * data+linesize for the bitmap of this subtitle.
3856  * Can be set for text/ass as well once they are rendered.
3857  */
3859  int linesize[4];
3860 
3862 
3863  char *text; ///< 0 terminated plain UTF-8 text
3864 
3865  /**
3866  * 0 terminated ASS/SSA compatible event line.
3867  * The presentation of this is unaffected by the other values in this
3868  * struct.
3869  */
3870  char *ass;
3871 
3872  int flags;
3873 } AVSubtitleRect;
3874 
3875 typedef struct AVSubtitle {
3876  uint16_t format; /* 0 = graphics */
3877  uint32_t start_display_time; /* relative to packet pts, in ms */
3878  uint32_t end_display_time; /* relative to packet pts, in ms */
3879  unsigned num_rects;
3881  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3882 } AVSubtitle;
3883 
3884 /**
3885  * This struct describes the properties of an encoded stream.
3886  *
3887  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3888  * be allocated with avcodec_parameters_alloc() and freed with
3889  * avcodec_parameters_free().
3890  */
3891 typedef struct AVCodecParameters {
3892  /**
3893  * General type of the encoded data.
3894  */
3896  /**
3897  * Specific type of the encoded data (the codec used).
3898  */
3900  /**
3901  * Additional information about the codec (corresponds to the AVI FOURCC).
3902  */
3903  uint32_t codec_tag;
3904 
3905  /**
3906  * Extra binary data needed for initializing the decoder, codec-dependent.
3907  *
3908  * Must be allocated with av_malloc() and will be freed by
3909  * avcodec_parameters_free(). The allocated size of extradata must be at
3910  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3911  * bytes zeroed.
3912  */
3914  /**
3915  * Size of the extradata content in bytes.
3916  */
3918 
3919  /**
3920  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3921  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3922  */
3923  int format;
3924 
3925  /**
3926  * The average bitrate of the encoded data (in bits per second).
3927  */
3928  int64_t bit_rate;
3929 
3930  /**
3931  * The number of bits per sample in the codedwords.
3932  *
3933  * This is basically the bitrate per sample. It is mandatory for a bunch of
3934  * formats to actually decode them. It's the number of bits for one sample in
3935  * the actual coded bitstream.
3936  *
3937  * This could be for example 4 for ADPCM
3938  * For PCM formats this matches bits_per_raw_sample
3939  * Can be 0
3940  */
3942 
3943  /**
3944  * This is the number of valid bits in each output sample. If the
3945  * sample format has more bits, the least significant bits are additional
3946  * padding bits, which are always 0. Use right shifts to reduce the sample
3947  * to its actual size. For example, audio formats with 24 bit samples will
3948  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3949  * To get the original sample use "(int32_t)sample >> 8"."
3950  *
3951  * For ADPCM this might be 12 or 16 or similar
3952  * Can be 0
3953  */
3955 
3956  /**
3957  * Codec-specific bitstream restrictions that the stream conforms to.
3958  */
3959  int profile;
3960  int level;
3961 
3962  /**
3963  * Video only. The dimensions of the video frame in pixels.
3964  */
3965  int width;
3966  int height;
3967 
3968  /**
3969  * Video only. The aspect ratio (width / height) which a single pixel
3970  * should have when displayed.
3971  *
3972  * When the aspect ratio is unknown / undefined, the numerator should be
3973  * set to 0 (the denominator may have any value).
3974  */
3976 
3977  /**
3978  * Video only. The order of the fields in interlaced video.
3979  */
3981 
3982  /**
3983  * Video only. Additional colorspace characteristics.
3984  */
3990 
3991  /**
3992  * Video only. Number of delayed frames.
3993  */
3995 
3996  /**
3997  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3998  * unknown or unspecified, otherwise the number of bits set must be equal to
3999  * the channels field.
4000  */
4001  uint64_t channel_layout;
4002  /**
4003  * Audio only. The number of audio channels.
4004  */
4006  /**
4007  * Audio only. The number of audio samples per second.
4008  */
4010  /**
4011  * Audio only. The number of bytes per coded audio frame, required by some
4012  * formats.
4013  *
4014  * Corresponds to nBlockAlign in WAVEFORMATEX.
4015  */
4017  /**
4018  * Audio only. Audio frame size, if known. Required by some formats to be static.
4019  */
4021 
4022  /**
4023  * Audio only. The amount of padding (in samples) inserted by the encoder at
4024  * the beginning of the audio. I.e. this number of leading decoded samples
4025  * must be discarded by the caller to get the original audio without leading
4026  * padding.
4027  */
4029  /**
4030  * Audio only. The amount of padding (in samples) appended by the encoder to
4031  * the end of the audio. I.e. this number of decoded samples must be
4032  * discarded by the caller from the end of the stream to get the original
4033  * audio without any trailing padding.
4034  */
4036  /**
4037  * Audio only. Number of samples to skip after a discontinuity.
4038  */
4041 
4042 /**
4043  * Iterate over all registered codecs.
4044  *
4045  * @param opaque a pointer where libavcodec will store the iteration state. Must
4046  * point to NULL to start the iteration.
4047  *
4048  * @return the next registered codec or NULL when the iteration is
4049  * finished
4050  */
4051 const AVCodec *av_codec_iterate(void **opaque);
4052 
4053 #if FF_API_NEXT
4054 /**
4055  * If c is NULL, returns the first registered codec,
4056  * if c is non-NULL, returns the next registered codec after c,
4057  * or NULL if c is the last one.
4058  */
4060 AVCodec *av_codec_next(const AVCodec *c);
4061 #endif
4062 
4063 /**
4064  * Return the LIBAVCODEC_VERSION_INT constant.
4065  */
4066 unsigned avcodec_version(void);
4067 
4068 /**
4069  * Return the libavcodec build-time configuration.
4070  */
4071 const char *avcodec_configuration(void);
4072 
4073 /**
4074  * Return the libavcodec license.
4075  */
4076 const char *avcodec_license(void);
4077 
4078 #if FF_API_NEXT
4079 /**
4080  * Register the codec codec and initialize libavcodec.
4081  *
4082  * @warning either this function or avcodec_register_all() must be called
4083  * before any other libavcodec functions.
4084  *
4085  * @see avcodec_register_all()
4086  */
4088 void avcodec_register(AVCodec *codec);
4089 
4090 /**
4091  * Register all the codecs, parsers and bitstream filters which were enabled at
4092  * configuration time. If you do not call this function you can select exactly
4093  * which formats you want to support, by using the individual registration
4094  * functions.
4095  *
4096  * @see avcodec_register
4097  * @see av_register_codec_parser
4098  * @see av_register_bitstream_filter
4099  */
4101 void avcodec_register_all(void);
4102 #endif
4103 
4104 /**
4105  * Allocate an AVCodecContext and set its fields to default values. The
4106  * resulting struct should be freed with avcodec_free_context().
4107  *
4108  * @param codec if non-NULL, allocate private data and initialize defaults
4109  * for the given codec. It is illegal to then call avcodec_open2()
4110  * with a different codec.
4111  * If NULL, then the codec-specific defaults won't be initialized,
4112  * which may result in suboptimal default settings (this is
4113  * important mainly for encoders, e.g. libx264).
4114  *
4115  * @return An AVCodecContext filled with default values or NULL on failure.
4116  */
4118 
4119 /**
4120  * Free the codec context and everything associated with it and write NULL to
4121  * the provided pointer.
4122  */
4123 void avcodec_free_context(AVCodecContext **avctx);
4124 
4125 #if FF_API_GET_CONTEXT_DEFAULTS
4126 /**
4127  * @deprecated This function should not be used, as closing and opening a codec
4128  * context multiple time is not supported. A new codec context should be
4129  * allocated for each new use.
4130  */
4132 #endif
4133 
4134 /**
4135  * Get the AVClass for AVCodecContext. It can be used in combination with
4136  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4137  *
4138  * @see av_opt_find().
4139  */
4140 const AVClass *avcodec_get_class(void);
4141 
4142 #if FF_API_COPY_CONTEXT
4143 /**
4144  * Get the AVClass for AVFrame. It can be used in combination with
4145  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4146  *
4147  * @see av_opt_find().
4148  */
4149 const AVClass *avcodec_get_frame_class(void);
4150 
4151 /**
4152  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4153  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4154  *
4155  * @see av_opt_find().
4156  */
4158 
4159 /**
4160  * Copy the settings of the source AVCodecContext into the destination
4161  * AVCodecContext. The resulting destination codec context will be
4162  * unopened, i.e. you are required to call avcodec_open2() before you
4163  * can use this AVCodecContext to decode/encode video/audio data.
4164  *
4165  * @param dest target codec context, should be initialized with
4166  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4167  * @param src source codec context
4168  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4169  *
4170  * @deprecated The semantics of this function are ill-defined and it should not
4171  * be used. If you need to transfer the stream parameters from one codec context
4172  * to another, use an intermediate AVCodecParameters instance and the
4173  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4174  * functions.
4175  */
4178 #endif
4179 
4180 /**
4181  * Allocate a new AVCodecParameters and set its fields to default values
4182  * (unknown/invalid/0). The returned struct must be freed with
4183  * avcodec_parameters_free().
4184  */
4186 
4187 /**
4188  * Free an AVCodecParameters instance and everything associated with it and
4189  * write NULL to the supplied pointer.
4190  */
4192 
4193 /**
4194  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4195  * replaced with newly allocated duplicates of the corresponding fields in src.
4196  *
4197  * @return >= 0 on success, a negative AVERROR code on failure.
4198  */
4200 
4201 /**
4202  * Fill the parameters struct based on the values from the supplied codec
4203  * context. Any allocated fields in par are freed and replaced with duplicates
4204  * of the corresponding fields in codec.
4205  *
4206  * @return >= 0 on success, a negative AVERROR code on failure
4207  */
4209  const AVCodecContext *codec);
4210 
4211 /**
4212  * Fill the codec context based on the values from the supplied codec
4213  * parameters. Any allocated fields in codec that have a corresponding field in
4214  * par are freed and replaced with duplicates of the corresponding field in par.
4215  * Fields in codec that do not have a counterpart in par are not touched.
4216  *
4217  * @return >= 0 on success, a negative AVERROR code on failure.
4218  */
4220  const AVCodecParameters *par);
4221 
4222 /**
4223  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4224  * function the context has to be allocated with avcodec_alloc_context3().
4225  *
4226  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4227  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4228  * retrieving a codec.
4229  *
4230  * @warning This function is not thread safe!
4231  *
4232  * @note Always call this function before using decoding routines (such as
4233  * @ref avcodec_receive_frame()).
4234  *
4235  * @code
4236  * avcodec_register_all();
4237  * av_dict_set(&opts, "b", "2.5M", 0);
4238  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4239  * if (!codec)
4240  * exit(1);
4241  *
4242  * context = avcodec_alloc_context3(codec);
4243  *
4244  * if (avcodec_open2(context, codec, opts) < 0)
4245  * exit(1);
4246  * @endcode
4247  *
4248  * @param avctx The context to initialize.
4249  * @param codec The codec to open this context for. If a non-NULL codec has been
4250  * previously passed to avcodec_alloc_context3() or
4251  * for this context, then this parameter MUST be either NULL or
4252  * equal to the previously passed codec.
4253  * @param options A dictionary filled with AVCodecContext and codec-private options.
4254  * On return this object will be filled with options that were not found.
4255  *
4256  * @return zero on success, a negative value on error
4257  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4258  * av_dict_set(), av_opt_find().
4259  */
4260 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4261 
4262 /**
4263  * Close a given AVCodecContext and free all the data associated with it
4264  * (but not the AVCodecContext itself).
4265  *
4266  * Calling this function on an AVCodecContext that hasn't been opened will free
4267  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4268  * codec. Subsequent calls will do nothing.
4269  *
4270  * @note Do not use this function. Use avcodec_free_context() to destroy a
4271  * codec context (either open or closed). Opening and closing a codec context
4272  * multiple times is not supported anymore -- use multiple codec contexts
4273  * instead.
4274  */
4275 int avcodec_close(AVCodecContext *avctx);
4276 
4277 /**
4278  * Free all allocated data in the given subtitle struct.
4279  *
4280  * @param sub AVSubtitle to free.
4281  */
4282 void avsubtitle_free(AVSubtitle *sub);
4283 
4284 /**
4285  * @}
4286  */
4287 
4288 /**
4289  * @addtogroup lavc_packet
4290  * @{
4291  */
4292 
4293 /**
4294  * Allocate an AVPacket and set its fields to default values. The resulting
4295  * struct must be freed using av_packet_free().
4296  *
4297  * @return An AVPacket filled with default values or NULL on failure.
4298  *
4299  * @note this only allocates the AVPacket itself, not the data buffers. Those
4300  * must be allocated through other means such as av_new_packet.
4301  *
4302  * @see av_new_packet
4303  */
4304 AVPacket *av_packet_alloc(void);
4305 
4306 /**
4307  * Create a new packet that references the same data as src.
4308  *
4309  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4310  *
4311  * @return newly created AVPacket on success, NULL on error.
4312  *
4313  * @see av_packet_alloc
4314  * @see av_packet_ref
4315  */
4317 
4318 /**
4319  * Free the packet, if the packet is reference counted, it will be
4320  * unreferenced first.
4321  *
4322  * @param pkt packet to be freed. The pointer will be set to NULL.
4323  * @note passing NULL is a no-op.
4324  */
4325 void av_packet_free(AVPacket **pkt);
4326 
4327 /**
4328  * Initialize optional fields of a packet with default values.
4329  *
4330  * Note, this does not touch the data and size members, which have to be
4331  * initialized separately.
4332  *
4333  * @param pkt packet
4334  */
4335 void av_init_packet(AVPacket *pkt);
4336 
4337 /**
4338  * Allocate the payload of a packet and initialize its fields with
4339  * default values.
4340  *
4341  * @param pkt packet
4342  * @param size wanted payload size
4343  * @return 0 if OK, AVERROR_xxx otherwise
4344  */
4345 int av_new_packet(AVPacket *pkt, int size);
4346 
4347 /**
4348  * Reduce packet size, correctly zeroing padding
4349  *
4350  * @param pkt packet
4351  * @param size new size
4352  */
4353 void av_shrink_packet(AVPacket *pkt, int size);
4354 
4355 /**
4356  * Increase packet size, correctly zeroing padding
4357  *
4358  * @param pkt packet
4359  * @param grow_by number of bytes by which to increase the size of the packet
4360  */
4361 int av_grow_packet(AVPacket *pkt, int grow_by);
4362 
4363 /**
4364  * Initialize a reference-counted packet from av_malloc()ed data.
4365  *
4366  * @param pkt packet to be initialized. This function will set the data, size,
4367  * buf and destruct fields, all others are left untouched.
4368  * @param data Data allocated by av_malloc() to be used as packet data. If this
4369  * function returns successfully, the data is owned by the underlying AVBuffer.
4370  * The caller may not access the data through other means.
4371  * @param size size of data in bytes, without the padding. I.e. the full buffer
4372  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4373  *
4374  * @return 0 on success, a negative AVERROR on error
4375  */
4377 
4378 #if FF_API_AVPACKET_OLD_API
4379 /**
4380  * @warning This is a hack - the packet memory allocation stuff is broken. The
4381  * packet is allocated if it was not really allocated.
4382  *
4383  * @deprecated Use av_packet_ref or av_packet_make_refcounted
4384  */
4386 int av_dup_packet(AVPacket *pkt);
4387 /**
4388  * Copy packet, including contents
4389  *
4390  * @return 0 on success, negative AVERROR on fail
4391  *
4392  * @deprecated Use av_packet_ref
4393  */
4395 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4396 
4397 /**
4398  * Copy packet side data
4399  *
4400  * @return 0 on success, negative AVERROR on fail
4401  *
4402  * @deprecated Use av_packet_copy_props
4403  */
4405 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4406 
4407 /**
4408  * Free a packet.
4409  *
4410  * @deprecated Use av_packet_unref
4411  *
4412  * @param pkt packet to free
4413  */
4415 void av_free_packet(AVPacket *pkt);
4416 #endif
4417 /**
4418  * Allocate new information of a packet.
4419  *
4420  * @param pkt packet
4421  * @param type side information type
4422  * @param size side information size
4423  * @return pointer to fresh allocated data or NULL otherwise
4424  */
4426  int size);
4427 
4428 /**
4429  * Wrap an existing array as a packet side data.
4430  *
4431  * @param pkt packet
4432  * @param type side information type
4433  * @param data the side data array. It must be allocated with the av_malloc()
4434  * family of functions. The ownership of the data is transferred to
4435  * pkt.
4436  * @param size side information size
4437  * @return a non-negative number on success, a negative AVERROR code on
4438  * failure. On failure, the packet is unchanged and the data remains
4439  * owned by the caller.
4440  */
4442  uint8_t *data, size_t size);
4443 
4444 /**
4445  * Shrink the already allocated side data buffer
4446  *
4447  * @param pkt packet
4448  * @param type side information type
4449  * @param size new side information size
4450  * @return 0 on success, < 0 on failure
4451  */
4453  int size);
4454 
4455 /**
4456  * Get side information from packet.
4457  *
4458  * @param pkt packet
4459  * @param type desired side information type
4460  * @param size pointer for side information size to store (optional)
4461  * @return pointer to data if present or NULL otherwise
4462  */
4464  int *size);
4465 
4466 #if FF_API_MERGE_SD_API
4469 
4472 #endif
4473 
4475 
4476 /**
4477  * Pack a dictionary for use in side_data.
4478  *
4479  * @param dict The dictionary to pack.
4480  * @param size pointer to store the size of the returned data
4481  * @return pointer to data if successful, NULL otherwise
4482  */
4484 /**
4485  * Unpack a dictionary from side_data.
4486  *
4487  * @param data data from side_data
4488  * @param size size of the data
4489  * @param dict the metadata storage dictionary
4490  * @return 0 on success, < 0 on failure
4491  */
4492 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4493 
4494 
4495 /**
4496  * Convenience function to free all the side data stored.
4497  * All the other fields stay untouched.
4498  *
4499  * @param pkt packet
4500  */
4502 
4503 /**
4504  * Setup a new reference to the data described by a given packet
4505  *
4506  * If src is reference-counted, setup dst as a new reference to the
4507  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4508  * data from src into it.
4509  *
4510  * All the other fields are copied from src.
4511  *
4512  * @see av_packet_unref
4513  *
4514  * @param dst Destination packet
4515  * @param src Source packet
4516  *
4517  * @return 0 on success, a negative AVERROR on error.
4518  */
4519 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4520 
4521 /**
4522  * Wipe the packet.
4523  *
4524  * Unreference the buffer referenced by the packet and reset the
4525  * remaining packet fields to their default values.
4526  *
4527  * @param pkt The packet to be unreferenced.
4528  */
4530 
4531 /**
4532  * Move every field in src to dst and reset src.
4533  *
4534  * @see av_packet_unref
4535  *
4536  * @param src Source packet, will be reset
4537  * @param dst Destination packet
4538  */
4540 
4541 /**
4542  * Copy only "properties" fields from src to dst.
4543  *
4544  * Properties for the purpose of this function are all the fields
4545  * beside those related to the packet data (buf, data, size)
4546  *
4547  * @param dst Destination packet
4548  * @param src Source packet
4549  *
4550  * @return 0 on success AVERROR on failure.
4551  */
4552 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4553 
4554 /**
4555  * Ensure the data described by a given packet is reference counted.
4556  *
4557  * @note This function does not ensure that the reference will be writable.
4558  * Use av_packet_make_writable instead for that purpose.
4559  *
4560  * @see av_packet_ref
4561  * @see av_packet_make_writable
4562  *
4563  * @param pkt packet whose data should be made reference counted.
4564  *
4565  * @return 0 on success, a negative AVERROR on error. On failure, the
4566  * packet is unchanged.
4567  */
4569 
4570 /**
4571  * Create a writable reference for the data described by a given packet,
4572  * avoiding data copy if possible.
4573  *
4574  * @param pkt Packet whose data should be made writable.
4575  *
4576  * @return 0 on success, a negative AVERROR on failure. On failure, the
4577  * packet is unchanged.
4578  */
4580 
4581 /**
4582  * Convert valid timing fields (timestamps / durations) in a packet from one
4583  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4584  * ignored.
4585  *
4586  * @param pkt packet on which the conversion will be performed
4587  * @param tb_src source timebase, in which the timing fields in pkt are
4588  * expressed
4589  * @param tb_dst destination timebase, to which the timing fields will be
4590  * converted
4591  */
4592 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4593 
4594 /**
4595  * @}
4596  */
4597 
4598 /**
4599  * @addtogroup lavc_decoding
4600  * @{
4601  */
4602 
4603 /**
4604  * Find a registered decoder with a matching codec ID.
4605  *
4606  * @param id AVCodecID of the requested decoder
4607  * @return A decoder if one was found, NULL otherwise.
4608  */
4610 
4611 /**
4612  * Find a registered decoder with the specified name.
4613  *
4614  * @param name name of the requested decoder
4615  * @return A decoder if one was found, NULL otherwise.
4616  */
4618 
4619 /**
4620  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4621  * it can be called by custom get_buffer2() implementations for decoders without
4622  * AV_CODEC_CAP_DR1 set.
4623  */
4625 
4626 /**
4627  * Modify width and height values so that they will result in a memory
4628  * buffer that is acceptable for the codec if you do not use any horizontal
4629  * padding.
4630  *
4631  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4632  */
4634 
4635 /**
4636  * Modify width and height values so that they will result in a memory
4637  * buffer that is acceptable for the codec if you also ensure that all
4638  * line sizes are a multiple of the respective linesize_align[i].
4639  *
4640  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4641  */
4643  int linesize_align[AV_NUM_DATA_POINTERS]);
4644 
4645 /**
4646  * Converts AVChromaLocation to swscale x/y chroma position.
4647  *
4648  * The positions represent the chroma (0,0) position in a coordinates system
4649  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4650  *
4651  * @param xpos horizontal chroma sample position
4652  * @param ypos vertical chroma sample position
4653  */
4654 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4655 
4656 /**
4657  * Converts swscale x/y chroma position to AVChromaLocation.
4658  *
4659  * The positions represent the chroma (0,0) position in a coordinates system
4660  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4661  *
4662  * @param xpos horizontal chroma sample position
4663  * @param ypos vertical chroma sample position
4664  */
4665 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4666 
4667 /**
4668  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4669  *
4670  * Some decoders may support multiple frames in a single AVPacket. Such
4671  * decoders would then just decode the first frame and the return value would be
4672  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4673  * called again with an AVPacket containing the remaining data in order to
4674  * decode the second frame, etc... Even if no frames are returned, the packet
4675  * needs to be fed to the decoder with remaining data until it is completely
4676  * consumed or an error occurs.
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 samples. It is safe to flush even those decoders that are not
4684  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4685  *
4686  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4687  * larger than the actual read bytes because some optimized bitstream
4688  * readers read 32 or 64 bits at once and could read over the end.
4689  *
4690  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4691  * before packets may be fed to the decoder.
4692  *
4693  * @param avctx the codec context
4694  * @param[out] frame The AVFrame in which to store decoded audio samples.
4695  * The decoder will allocate a buffer for the decoded frame by
4696  * calling the AVCodecContext.get_buffer2() callback.
4697  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4698  * reference counted and the returned reference belongs to the
4699  * caller. The caller must release the frame using av_frame_unref()
4700  * when the frame is no longer needed. The caller may safely write
4701  * to the frame if av_frame_is_writable() returns 1.
4702  * When AVCodecContext.refcounted_frames is set to 0, the returned
4703  * reference belongs to the decoder and is valid only until the
4704  * next call to this function or until closing or flushing the
4705  * decoder. The caller may not write to it.
4706  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4707  * non-zero. Note that this field being set to zero
4708  * does not mean that an error has occurred. For
4709  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4710  * call is guaranteed to produce a frame.
4711  * @param[in] avpkt The input AVPacket containing the input buffer.
4712  * At least avpkt->data and avpkt->size should be set. Some
4713  * decoders might also require additional fields to be set.
4714  * @return A negative error code is returned if an error occurred during
4715  * decoding, otherwise the number of bytes consumed from the input
4716  * AVPacket is returned.
4717  *
4718 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4719  */
4722  int *got_frame_ptr, const AVPacket *avpkt);
4723 
4724 /**
4725  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4726  * Some decoders may support multiple frames in a single AVPacket, such
4727  * decoders would then just decode the first frame.
4728  *
4729  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4730  * the actual read bytes because some optimized bitstream readers read 32 or 64
4731  * bits at once and could read over the end.
4732  *
4733  * @warning The end of the input buffer buf should be set to 0 to ensure that
4734  * no overreading happens for damaged MPEG streams.
4735  *
4736  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4737  * between input and output, these need to be fed with avpkt->data=NULL,
4738  * avpkt->size=0 at the end to return the remaining frames.
4739  *
4740  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4741  * before packets may be fed to the decoder.
4742  *
4743  * @param avctx the codec context
4744  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4745  * Use av_frame_alloc() to get an AVFrame. The codec will
4746  * allocate memory for the actual bitmap by calling the
4747  * AVCodecContext.get_buffer2() callback.
4748  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4749  * reference counted and the returned reference belongs to the
4750  * caller. The caller must release the frame using av_frame_unref()
4751  * when the frame is no longer needed. The caller may safely write
4752  * to the frame if av_frame_is_writable() returns 1.
4753  * When AVCodecContext.refcounted_frames is set to 0, the returned
4754  * reference belongs to the decoder and is valid only until the
4755  * next call to this function or until closing or flushing the
4756  * decoder. The caller may not write to it.
4757  *
4758  * @param[in] avpkt The input AVPacket containing the input buffer.
4759  * You can create such packet with av_init_packet() and by then setting
4760  * data and size, some decoders might in addition need other fields like
4761  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4762  * fields possible.
4763  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4764  * @return On error a negative value is returned, otherwise the number of bytes
4765  * used or zero if no frame could be decompressed.
4766  *
4767  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4768  */
4770 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4771  int *got_picture_ptr,
4772  const AVPacket *avpkt);
4773 
4774 /**
4775  * Decode a subtitle message.
4776  * Return a negative value on error, otherwise return the number of bytes used.
4777  * If no subtitle could be decompressed, got_sub_ptr is zero.
4778  * Otherwise, the subtitle is stored in *sub.
4779  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4780  * simplicity, because the performance difference is expect to be negligible
4781  * and reusing a get_buffer written for video codecs would probably perform badly
4782  * due to a potentially very different allocation pattern.
4783  *
4784  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4785  * and output. This means that for some packets they will not immediately
4786  * produce decoded output and need to be flushed at the end of decoding to get
4787  * all the decoded data. Flushing is done by calling this function with packets
4788  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4789  * returning subtitles. It is safe to flush even those decoders that are not
4790  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4791  *
4792  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4793  * before packets may be fed to the decoder.
4794  *
4795  * @param avctx the codec context
4796  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4797  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4798  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4799  * @param[in] avpkt The input AVPacket containing the input buffer.
4800  */
4802  int *got_sub_ptr,
4803  AVPacket *avpkt);
4804 
4805 /**
4806  * Supply raw packet data as input to a decoder.
4807  *
4808  * Internally, this call will copy relevant AVCodecContext fields, which can
4809  * influence decoding per-packet, and apply them when the packet is actually
4810  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4811  * decoder to drop the frame contained by the packet sent with this function.)
4812  *
4813  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4814  * larger than the actual read bytes because some optimized bitstream
4815  * readers read 32 or 64 bits at once and could read over the end.
4816  *
4817  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4818  * on the same AVCodecContext. It will return unexpected results now
4819  * or in future libavcodec versions.
4820  *
4821  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4822  * before packets may be fed to the decoder.
4823  *
4824  * @param avctx codec context
4825  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4826  * frame, or several complete audio frames.
4827  * Ownership of the packet remains with the caller, and the
4828  * decoder will not write to the packet. The decoder may create
4829  * a reference to the packet data (or copy it if the packet is
4830  * not reference-counted).
4831  * Unlike with older APIs, the packet is always fully consumed,
4832  * and if it contains multiple frames (e.g. some audio codecs),
4833  * will require you to call avcodec_receive_frame() multiple
4834  * times afterwards before you can send a new packet.
4835  * It can be NULL (or an AVPacket with data set to NULL and
4836  * size set to 0); in this case, it is considered a flush
4837  * packet, which signals the end of the stream. Sending the
4838  * first flush packet will return success. Subsequent ones are
4839  * unnecessary and will return AVERROR_EOF. If the decoder
4840  * still has frames buffered, it will return them after sending
4841  * a flush packet.
4842  *
4843  * @return 0 on success, otherwise negative error code:
4844  * AVERROR(EAGAIN): input is not accepted in the current state - user
4845  * must read output with avcodec_receive_frame() (once
4846  * all output is read, the packet should be resent, and
4847  * the call will not fail with EAGAIN).
4848  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4849  * be sent to it (also returned if more than 1 flush
4850  * packet is sent)
4851  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4852  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4853  * other errors: legitimate decoding errors
4854  */
4855 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4856 
4857 /**
4858  * Return decoded output data from a decoder.
4859  *
4860  * @param avctx codec context
4861  * @param frame This will be set to a reference-counted video or audio
4862  * frame (depending on the decoder type) allocated by the
4863  * decoder. Note that the function will always call
4864  * av_frame_unref(frame) before doing anything else.
4865  *
4866  * @return
4867  * 0: success, a frame was returned
4868  * AVERROR(EAGAIN): output is not available in this state - user must try
4869  * to send new input
4870  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4871  * no more output frames
4872  * AVERROR(EINVAL): codec not opened, or it is an encoder
4873  * other negative values: legitimate decoding errors
4874  */
4876 
4877 /**
4878  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4879  * to retrieve buffered output packets.
4880  *
4881  * @param avctx codec context
4882  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4883  * Ownership of the frame remains with the caller, and the
4884  * encoder will not write to the frame. The encoder may create
4885  * a reference to the frame data (or copy it if the frame is
4886  * not reference-counted).
4887  * It can be NULL, in which case it is considered a flush
4888  * packet. This signals the end of the stream. If the encoder
4889  * still has packets buffered, it will return them after this
4890  * call. Once flushing mode has been entered, additional flush
4891  * packets are ignored, and sending frames will return
4892  * AVERROR_EOF.
4893  *
4894  * For audio:
4895  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4896  * can have any number of samples.
4897  * If it is not set, frame->nb_samples must be equal to
4898  * avctx->frame_size for all frames except the last.
4899  * The final frame may be smaller than avctx->frame_size.
4900  * @return 0 on success, otherwise negative error code:
4901  * AVERROR(EAGAIN): input is not accepted in the current state - user
4902  * must read output with avcodec_receive_packet() (once
4903  * all output is read, the packet should be resent, and
4904  * the call will not fail with EAGAIN).
4905  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4906  * be sent to it
4907  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4908  * decoder, or requires flush
4909  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4910  * other errors: legitimate decoding errors
4911  */
4912 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4913 
4914 /**
4915  * Read encoded data from the encoder.
4916  *
4917  * @param avctx codec context
4918  * @param avpkt This will be set to a reference-counted packet allocated by the
4919  * encoder. Note that the function will always call
4920  * av_frame_unref(frame) before doing anything else.
4921  * @return 0 on success, otherwise negative error code:
4922  * AVERROR(EAGAIN): output is not available in the current state - user
4923  * must try to send input
4924  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4925  * no more output packets
4926  * AVERROR(EINVAL): codec not opened, or it is an encoder
4927  * other errors: legitimate decoding errors
4928  */
4929 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4930 
4931 /**
4932  * Create and return a AVHWFramesContext with values adequate for hardware
4933  * decoding. This is meant to get called from the get_format callback, and is
4934  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4935  * This API is for decoding with certain hardware acceleration modes/APIs only.
4936  *
4937  * The returned AVHWFramesContext is not initialized. The caller must do this
4938  * with av_hwframe_ctx_init().
4939  *
4940  * Calling this function is not a requirement, but makes it simpler to avoid
4941  * codec or hardware API specific details when manually allocating frames.
4942  *
4943  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
4944  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
4945  * it unnecessary to call this function or having to care about
4946  * AVHWFramesContext initialization at all.
4947  *
4948  * There are a number of requirements for calling this function:
4949  *
4950  * - It must be called from get_format with the same avctx parameter that was
4951  * passed to get_format. Calling it outside of get_format is not allowed, and
4952  * can trigger undefined behavior.
4953  * - The function is not always supported (see description of return values).
4954  * Even if this function returns successfully, hwaccel initialization could
4955  * fail later. (The degree to which implementations check whether the stream
4956  * is actually supported varies. Some do this check only after the user's
4957  * get_format callback returns.)
4958  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
4959  * user decides to use a AVHWFramesContext prepared with this API function,
4960  * the user must return the same hw_pix_fmt from get_format.
4961  * - The device_ref passed to this function must support the given hw_pix_fmt.
4962  * - After calling this API function, it is the user's responsibility to
4963  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
4964  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
4965  * before returning from get_format (this is implied by the normal
4966  * AVCodecContext.hw_frames_ctx API rules).
4967  * - The AVHWFramesContext parameters may change every time time get_format is
4968  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
4969  * you are inherently required to go through this process again on every
4970  * get_format call.
4971  * - It is perfectly possible to call this function without actually using
4972  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
4973  * previously initialized AVHWFramesContext, and calling this API function
4974  * only to test whether the required frame parameters have changed.
4975  * - Fields that use dynamically allocated values of any kind must not be set
4976  * by the user unless setting them is explicitly allowed by the documentation.
4977  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
4978  * the new free callback must call the potentially set previous free callback.
4979  * This API call may set any dynamically allocated fields, including the free
4980  * callback.
4981  *
4982  * The function will set at least the following fields on AVHWFramesContext
4983  * (potentially more, depending on hwaccel API):
4984  *
4985  * - All fields set by av_hwframe_ctx_alloc().
4986  * - Set the format field to hw_pix_fmt.
4987  * - Set the sw_format field to the most suited and most versatile format. (An
4988  * implication is that this will prefer generic formats over opaque formats
4989  * with arbitrary restrictions, if possible.)
4990  * - Set the width/height fields to the coded frame size, rounded up to the
4991  * API-specific minimum alignment.
4992  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
4993  * field to the number of maximum reference surfaces possible with the codec,
4994  * plus 1 surface for the user to work (meaning the user can safely reference
4995  * at most 1 decoded surface at a time), plus additional buffering introduced
4996  * by frame threading. If the hwaccel does not require pre-allocation, the
4997  * field is left to 0, and the decoder will allocate new surfaces on demand
4998  * during decoding.
4999  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
5000  * hardware API.
5001  *
5002  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
5003  * with basic frame parameters set.
5004  *
5005  * The function is stateless, and does not change the AVCodecContext or the
5006  * device_ref AVHWDeviceContext.
5007  *
5008  * @param avctx The context which is currently calling get_format, and which
5009  * implicitly contains all state needed for filling the returned
5010  * AVHWFramesContext properly.
5011  * @param device_ref A reference to the AVHWDeviceContext describing the device
5012  * which will be used by the hardware decoder.
5013  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
5014  * @param out_frames_ref On success, set to a reference to an _uninitialized_
5015  * AVHWFramesContext, created from the given device_ref.
5016  * Fields will be set to values required for decoding.
5017  * Not changed if an error is returned.
5018  * @return zero on success, a negative value on error. The following error codes
5019  * have special semantics:
5020  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
5021  * is always manual, or it is a decoder which does not
5022  * support setting AVCodecContext.hw_frames_ctx at all,
5023  * or it is a software format.
5024  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
5025  * this configuration, or the device_ref is not supported
5026  * for the hwaccel referenced by hw_pix_fmt.
5027  */
5029  AVBufferRef *device_ref,
5031  AVBufferRef **out_frames_ref);
5032 
5033 
5034 
5035 /**
5036  * @defgroup lavc_parsing Frame parsing
5037  * @{
5038  */
5039 
5042  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5043  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5044  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5045 };
5046 
5047 typedef struct AVCodecParserContext {
5048  void *priv_data;
5050  int64_t frame_offset; /* offset of the current frame */
5051  int64_t cur_offset; /* current offset
5052  (incremented by each av_parser_parse()) */
5053  int64_t next_frame_offset; /* offset of the next frame */
5054  /* video info */
5055  int pict_type; /* XXX: Put it back in AVCodecContext. */
5056  /**
5057  * This field is used for proper frame duration computation in lavf.
5058  * It signals, how much longer the frame duration of the current frame
5059  * is compared to normal frame duration.
5060  *
5061  * frame_duration = (1 + repeat_pict) * time_base
5062  *
5063  * It is used by codecs like H.264 to display telecined material.
5064  */
5065  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5066  int64_t pts; /* pts of the current frame */
5067  int64_t dts; /* dts of the current frame */
5068 
5069  /* private data */
5070  int64_t last_pts;
5071  int64_t last_dts;
5073 
5074 #define AV_PARSER_PTS_NB 4
5079 
5080  int flags;
5081 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5082 #define PARSER_FLAG_ONCE 0x0002
5083 /// Set if the parser has a valid file offset
5084 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5085 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5086 
5087  int64_t offset; ///< byte offset from starting packet start
5089 
5090  /**
5091  * Set by parser to 1 for key frames and 0 for non-key frames.
5092  * It is initialized to -1, so if the parser doesn't set this flag,
5093  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5094  * will be used.
5095  */
5097 
5098 #if FF_API_CONVERGENCE_DURATION
5099  /**
5100  * @deprecated unused
5101  */
5104 #endif
5105 
5106  // Timestamp generation support:
5107  /**
5108  * Synchronization point for start of timestamp generation.
5109  *
5110  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5111  * (default).
5112  *
5113  * For example, this corresponds to presence of H.264 buffering period
5114  * SEI message.
5115  */
5117 
5118  /**
5119  * Offset of the current timestamp against last timestamp sync point in
5120  * units of AVCodecContext.time_base.
5121  *
5122  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5123  * contain a valid timestamp offset.
5124  *
5125  * Note that the timestamp of sync point has usually a nonzero
5126  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5127  * the next frame after timestamp sync point will be usually 1.
5128  *
5129  * For example, this corresponds to H.264 cpb_removal_delay.
5130  */
5132 
5133  /**
5134  * Presentation delay of current frame in units of AVCodecContext.time_base.
5135  *
5136  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5137  * contain valid non-negative timestamp delta (presentation time of a frame
5138  * must not lie in the past).
5139  *
5140  * This delay represents the difference between decoding and presentation
5141  * time of the frame.
5142  *
5143  * For example, this corresponds to H.264 dpb_output_delay.
5144  */
5146 
5147  /**
5148  * Position of the packet in file.
5149  *
5150  * Analogous to cur_frame_pts/dts
5151  */
5153 
5154  /**
5155  * Byte position of currently parsed frame in stream.
5156  */
5157  int64_t pos;
5158 
5159  /**
5160  * Previous frame byte position.
5161  */
5162  int64_t last_pos;
5163 
5164  /**
5165  * Duration of the current frame.
5166  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5167  * For all other types, this is in units of AVCodecContext.time_base.
5168  */
5170 
5172 
5173  /**
5174  * Indicate whether a picture is coded as a frame, top field or bottom field.
5175  *
5176  * For example, H.264 field_pic_flag equal to 0 corresponds to
5177  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5178  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5179  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5180  */
5182 
5183  /**
5184  * Picture number incremented in presentation or output order.
5185  * This field may be reinitialized at the first picture of a new sequence.
5186  *
5187  * For example, this corresponds to H.264 PicOrderCnt.
5188  */
5190 
5191  /**
5192  * Dimensions of the decoded video intended for presentation.
5193  */
5194  int width;
5195  int height;
5196 
5197  /**
5198  * Dimensions of the coded video.
5199  */
5202 
5203  /**
5204  * The format of the coded data, corresponds to enum AVPixelFormat for video
5205  * and for enum AVSampleFormat for audio.
5206  *
5207  * Note that a decoder can have considerable freedom in how exactly it
5208  * decodes the data, so the format reported here might be different from the
5209  * one returned by a decoder.
5210  */
5211  int format;
5213 
5214 typedef struct AVCodecParser {
5215  int codec_ids[5]; /* several codec IDs are permitted */
5218  /* This callback never returns an error, a negative value means that
5219  * the frame start was in a previous packet. */
5221  AVCodecContext *avctx,
5222  const uint8_t **poutbuf, int *poutbuf_size,
5223  const uint8_t *buf, int buf_size);
5225  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5227 } AVCodecParser;
5228 
5229 /**
5230  * Iterate over all registered codec parsers.
5231  *
5232  * @param opaque a pointer where libavcodec will store the iteration state. Must
5233  * point to NULL to start the iteration.
5234  *
5235  * @return the next registered codec parser or NULL when the iteration is
5236  * finished
5237  */
5238 const AVCodecParser *av_parser_iterate(void **opaque);
5239 
5242 
5246 
5247 /**
5248  * Parse a packet.
5249  *
5250  * @param s parser context.
5251  * @param avctx codec context.
5252  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5253  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5254  * @param buf input buffer.
5255  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5256  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5257  To signal EOF, this should be 0 (so that the last frame
5258  can be output).
5259  * @param pts input presentation timestamp.
5260  * @param dts input decoding timestamp.
5261  * @param pos input byte position in stream.
5262  * @return the number of bytes of the input bitstream used.
5263  *
5264  * Example:
5265  * @code
5266  * while(in_len){
5267  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5268  * in_data, in_len,
5269  * pts, dts, pos);
5270  * in_data += len;
5271  * in_len -= len;
5272  *
5273  * if(size)
5274  * decode_frame(data, size);
5275  * }
5276  * @endcode
5277  */
5279  AVCodecContext *avctx,
5280  uint8_t **poutbuf, int *poutbuf_size,
5281  const uint8_t *buf, int buf_size,
5282  int64_t pts, int64_t dts,
5283  int64_t pos);
5284 
5285 /**
5286  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5287  * @deprecated use AVBitStreamFilter
5288  */
5290  AVCodecContext *avctx,
5291  uint8_t **poutbuf, int *poutbuf_size,
5292  const uint8_t *buf, int buf_size, int keyframe);
5294 
5295 /**
5296  * @}
5297  * @}
5298  */
5299 
5300 /**
5301  * @addtogroup lavc_encoding
5302  * @{
5303  */
5304 
5305 /**
5306  * Find a registered encoder with a matching codec ID.
5307  *
5308  * @param id AVCodecID of the requested encoder
5309  * @return An encoder if one was found, NULL otherwise.
5310  */
5312 
5313 /**
5314  * Find a registered encoder with the specified name.
5315  *
5316  * @param name name of the requested encoder
5317  * @return An encoder if one was found, NULL otherwise.
5318  */
5320 
5321 /**
5322  * Encode a frame of audio.
5323  *
5324  * Takes input samples from frame and writes the next output packet, if
5325  * available, to avpkt. The output packet does not necessarily contain data for
5326  * the most recent frame, as encoders can delay, split, and combine input frames
5327  * internally as needed.
5328  *
5329  * @param avctx codec context
5330  * @param avpkt output AVPacket.
5331  * The user can supply an output buffer by setting
5332  * avpkt->data and avpkt->size prior to calling the
5333  * function, but if the size of the user-provided data is not
5334  *