FFmpeg
target_dec_fuzzer.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 /* Targeted fuzzer that targets specific codecs depending on two
20  compile-time flags.
21  INSTRUCTIONS:
22 
23  * Get the very fresh clang, e.g. see http://libfuzzer.info#versions
24  * Get and build libFuzzer:
25  svn co http://llvm.org/svn/llvm-project/llvm/trunk/lib/Fuzzer
26  ./Fuzzer/build.sh
27  * build ffmpeg for fuzzing:
28  FLAGS="-fsanitize=address -fsanitize-coverage=trace-pc-guard,trace-cmp -g" CC="clang $FLAGS" CXX="clang++ $FLAGS" ./configure --disable-x86asm
29  make clean && make -j
30  * build the fuzz target.
31  Choose the value of FFMPEG_CODEC (e.g. AV_CODEC_ID_DVD_SUBTITLE) and
32  choose one of FUZZ_FFMPEG_VIDEO, FUZZ_FFMPEG_AUDIO, FUZZ_FFMPEG_SUBTITLE.
33  clang -fsanitize=address -fsanitize-coverage=trace-pc-guard,trace-cmp tools/target_dec_fuzzer.c -o target_dec_fuzzer -I. -DFFMPEG_CODEC=AV_CODEC_ID_MPEG1VIDEO -DFUZZ_FFMPEG_VIDEO ../../libfuzzer/libFuzzer.a -Llibavcodec -Llibavdevice -Llibavfilter -Llibavformat -Llibavresample -Llibavutil -Llibpostproc -Llibswscale -Llibswresample -Wl,--as-needed -Wl,-z,noexecstack -Wl,--warn-common -Wl,-rpath-link=:libpostproc:libswresample:libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample -lavdevice -lavfilter -lavformat -lavcodec -lswresample -lswscale -lavutil -ldl -lxcb -lxcb-shm -lxcb -lxcb-xfixes -lxcb -lxcb-shape -lxcb -lX11 -lasound -lm -lbz2 -lz -pthread
34  * create a corpus directory and put some samples there (empty dir is ok too):
35  mkdir CORPUS && cp some-files CORPUS
36 
37  * Run fuzzing:
38  ./target_dec_fuzzer -max_len=100000 CORPUS
39 
40  More info:
41  http://libfuzzer.info
42  http://tutorial.libfuzzer.info
43  https://github.com/google/oss-fuzz
44  http://lcamtuf.coredump.cx/afl/
45  https://security.googleblog.com/2016/08/guided-in-process-fuzzing-of-chrome.html
46 */
47 
48 #include "config.h"
49 #include "libavutil/avassert.h"
50 #include "libavutil/imgutils.h"
51 #include "libavutil/intreadwrite.h"
52 
53 #include "libavcodec/avcodec.h"
54 #include "libavcodec/bytestream.h"
55 #include "libavformat/avformat.h"
56 
57 //For FF_SANE_NB_CHANNELS, so we dont waste energy testing things that will get instantly rejected
58 #include "libavcodec/internal.h"
59 
60 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
61 
62 extern AVCodec * codec_list[];
63 
64 static void error(const char *err)
65 {
66  fprintf(stderr, "%s", err);
67  exit(1);
68 }
69 
70 static AVCodec *c = NULL;
72 {
73  AVCodec *res;
74 
75  res = avcodec_find_decoder(codec_id);
76  if (!res)
77  error("Failed to find decoder");
78  return res;
79 }
80 
81 static int subtitle_handler(AVCodecContext *avctx, void *frame,
82  int *got_sub_ptr, AVPacket *avpkt)
83 {
85  int ret = avcodec_decode_subtitle2(avctx, &sub, got_sub_ptr, avpkt);
86  if (ret >= 0 && *got_sub_ptr)
87  avsubtitle_free(&sub);
88  return ret;
89 }
90 
92  int *got_frame, const AVPacket *dummy)
93 {
94  int ret = avcodec_receive_frame(avctx, frame);
95  *got_frame = ret >= 0;
96  return ret;
97 }
98 
99 // Ensure we don't loop forever
100 const uint32_t maxiteration = 8096;
101 uint64_t maxpixels_per_frame = 4096 * 4096;
102 uint64_t maxpixels;
103 
104 uint64_t maxsamples_per_frame = 256*1024*32;
105 uint64_t maxsamples;
106 
107 static const uint64_t FUZZ_TAG = 0x4741542D5A5A5546ULL;
108 
110  const uint64_t fuzz_tag = FUZZ_TAG;
111  const uint8_t *last = data;
112  const uint8_t *end = data + size;
113  uint32_t it = 0;
114  uint64_t ec_pixels = 0;
115  uint64_t nb_samples = 0;
116  int (*decode_handler)(AVCodecContext *avctx, AVFrame *picture,
117  int *got_picture_ptr,
118  const AVPacket *avpkt) = NULL;
119  AVCodecParserContext *parser = NULL;
120  uint64_t keyframes = 0;
121  uint64_t flushpattern = -1;
123 
124  if (!c) {
125 #ifdef FFMPEG_DECODER
126 #define DECODER_SYMBOL0(CODEC) ff_##CODEC##_decoder
127 #define DECODER_SYMBOL(CODEC) DECODER_SYMBOL0(CODEC)
128  extern AVCodec DECODER_SYMBOL(FFMPEG_DECODER);
129  codec_list[0] = &DECODER_SYMBOL(FFMPEG_DECODER);
130 
131 #if FFMPEG_DECODER == tiff || FFMPEG_DECODER == tdsc
132  extern AVCodec DECODER_SYMBOL(mjpeg);
133  codec_list[1] = &DECODER_SYMBOL(mjpeg);
134 #endif
135 
136  c = &DECODER_SYMBOL(FFMPEG_DECODER);
137 #else
138  c = AVCodecInitialize(FFMPEG_CODEC); // Done once.
139 #endif
141  }
142 
143  switch (c->type) {
144  case AVMEDIA_TYPE_AUDIO :
145  case AVMEDIA_TYPE_VIDEO : decode_handler = audio_video_handler ; break;
146  case AVMEDIA_TYPE_SUBTITLE: decode_handler = subtitle_handler ; break;
147  }
148  switch (c->id) {
149  case AV_CODEC_ID_APE: maxsamples_per_frame /= 256; break;
150  }
153  switch (c->id) {
154  case AV_CODEC_ID_AGM: maxpixels /= 1024; break;
155  case AV_CODEC_ID_BINKVIDEO: maxpixels /= 32; break;
156  case AV_CODEC_ID_CFHD: maxpixels /= 128; break;
157  case AV_CODEC_ID_COOK: maxsamples /= 1<<20; break;
158  case AV_CODEC_ID_DIRAC: maxpixels /= 8192; break;
159  case AV_CODEC_ID_DST: maxsamples /= 1<<20; break;
160  case AV_CODEC_ID_DXV: maxpixels /= 32; break;
161  case AV_CODEC_ID_FFWAVESYNTH: maxsamples /= 16384; break;
162  case AV_CODEC_ID_G2M: maxpixels /= 1024; break;
163  case AV_CODEC_ID_GDV: maxpixels /= 512; break;
164  case AV_CODEC_ID_GIF: maxpixels /= 16; break;
165  case AV_CODEC_ID_HAP: maxpixels /= 128; break;
166  case AV_CODEC_ID_HEVC: maxpixels /= 16384; break;
167  case AV_CODEC_ID_HNM4_VIDEO: maxpixels /= 128; break;
168  case AV_CODEC_ID_IFF_ILBM: maxpixels /= 128; break;
169  case AV_CODEC_ID_INDEO4: maxpixels /= 128; break;
170  case AV_CODEC_ID_INTERPLAY_ACM: maxsamples /= 16384; break;
171  case AV_CODEC_ID_LAGARITH: maxpixels /= 1024; break;
172  case AV_CODEC_ID_LSCR: maxpixels /= 16; break;
173  case AV_CODEC_ID_MOTIONPIXELS:maxpixels /= 256; break;
174  case AV_CODEC_ID_MP4ALS: maxsamples /= 65536; break;
175  case AV_CODEC_ID_MSA1: maxpixels /= 16384; break;
176  case AV_CODEC_ID_MSRLE: maxpixels /= 16; break;
177  case AV_CODEC_ID_MSS2: maxpixels /= 16384; break;
178  case AV_CODEC_ID_MSZH: maxpixels /= 128; break;
179  case AV_CODEC_ID_OPUS: maxsamples /= 16384; break;
180  case AV_CODEC_ID_PNG: maxpixels /= 128; break;
181  case AV_CODEC_ID_APNG: maxpixels /= 128; break;
182  case AV_CODEC_ID_QTRLE: maxpixels /= 16; break;
183  case AV_CODEC_ID_RASC: maxpixels /= 16; break;
184  case AV_CODEC_ID_SANM: maxpixels /= 16; break;
185  case AV_CODEC_ID_SCPR: maxpixels /= 32; break;
186  case AV_CODEC_ID_SCREENPRESSO:maxpixels /= 64; break;
187  case AV_CODEC_ID_SMACKVIDEO: maxpixels /= 64; break;
188  case AV_CODEC_ID_SNOW: maxpixels /= 128; break;
189  case AV_CODEC_ID_TGV: maxpixels /= 32; break;
190  case AV_CODEC_ID_THEORA: maxpixels /= 1024; break;
191  case AV_CODEC_ID_TRUEMOTION2: maxpixels /= 1024; break;
192  case AV_CODEC_ID_VC1IMAGE: maxpixels /= 8192; break;
193  case AV_CODEC_ID_VMNC: maxpixels /= 8192; break;
194  case AV_CODEC_ID_VP7: maxpixels /= 256; break;
195  case AV_CODEC_ID_VP9: maxpixels /= 4096; break;
196  case AV_CODEC_ID_WAVPACK: maxsamples /= 1024; break;
197  case AV_CODEC_ID_WMV3IMAGE: maxpixels /= 8192; break;
198  case AV_CODEC_ID_WS_VQA: maxpixels /= 16384; break;
199  case AV_CODEC_ID_WMALOSSLESS: maxsamples /= 1024; break;
200  case AV_CODEC_ID_ZEROCODEC: maxpixels /= 128; break;
201  }
202 
205 
207  AVCodecContext* parser_avctx = avcodec_alloc_context3(NULL);
208  if (!ctx || !parser_avctx)
209  error("Failed memory allocation");
210 
211  if (ctx->max_pixels == 0 || ctx->max_pixels > maxpixels_per_frame)
212  ctx->max_pixels = maxpixels_per_frame; //To reduce false positive OOM and hangs
213 
215 
216  if (size > 1024) {
217  GetByteContext gbc;
218  int extradata_size;
219  int flags;
220  size -= 1024;
221  bytestream2_init(&gbc, data + size, 1024);
222  ctx->width = bytestream2_get_le32(&gbc);
223  ctx->height = bytestream2_get_le32(&gbc);
224  ctx->bit_rate = bytestream2_get_le64(&gbc);
225  ctx->bits_per_coded_sample = bytestream2_get_le32(&gbc);
226  // Try to initialize a parser for this codec, note, this may fail which just means we test without one
227  flags = bytestream2_get_byte(&gbc);
228  if (flags & 1)
229  parser = av_parser_init(c->id);
230  if (flags & 2)
232  if (flags & 4) {
234  if (flags & 8)
236  }
237  if ((flags & 0x10) && c->id != AV_CODEC_ID_H264)
238  ctx->flags2 |= AV_CODEC_FLAG2_FAST;
239 
240  if (flags & 0x40)
242 
243  extradata_size = bytestream2_get_le32(&gbc);
244 
245  ctx->sample_rate = bytestream2_get_le32(&gbc) & 0x7FFFFFFF;
246  ctx->channels = (unsigned)bytestream2_get_le32(&gbc) % FF_SANE_NB_CHANNELS;
247  ctx->block_align = bytestream2_get_le32(&gbc) & 0x7FFFFFFF;
248  ctx->codec_tag = bytestream2_get_le32(&gbc);
249  if (c->codec_tags) {
250  int n;
251  for (n = 0; c->codec_tags[n] != FF_CODEC_TAGS_END; n++);
252  ctx->codec_tag = c->codec_tags[ctx->codec_tag % n];
253  }
254  keyframes = bytestream2_get_le64(&gbc);
255  ctx->request_channel_layout = bytestream2_get_le64(&gbc);
256 
257  ctx->idct_algo = bytestream2_get_byte(&gbc) % 25;
258  flushpattern = bytestream2_get_le64(&gbc);
259 
260  if (flags & 0x20) {
261  switch (ctx->codec_id) {
262  case AV_CODEC_ID_AC3:
263  case AV_CODEC_ID_EAC3:
264  av_dict_set_int(&opts, "cons_noisegen", bytestream2_get_byte(&gbc) & 1, 0);
265  av_dict_set_int(&opts, "heavy_compr", bytestream2_get_byte(&gbc) & 1, 0);
266  av_dict_set_int(&opts, "target_level", (int)(bytestream2_get_byte(&gbc) % 32) - 31, 0);
267  av_dict_set_int(&opts, "dmix_mode", (int)(bytestream2_get_byte(&gbc) % 4) - 1, 0);
268  break;
269  }
270  }
271 
272 
273  if (extradata_size < size) {
274  ctx->extradata = av_mallocz(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
275  if (ctx->extradata) {
276  ctx->extradata_size = extradata_size;
277  size -= ctx->extradata_size;
278  memcpy(ctx->extradata, data + size, ctx->extradata_size);
279  }
280  }
281  if (av_image_check_size(ctx->width, ctx->height, 0, ctx))
282  ctx->width = ctx->height = 0;
283  }
284 
285  int res = avcodec_open2(ctx, c, &opts);
286  if (res < 0) {
287  avcodec_free_context(&ctx);
288  av_free(parser_avctx);
289  av_parser_close(parser);
290  av_dict_free(&opts);
291  return 0; // Failure of avcodec_open2() does not imply that a issue was found
292  }
293  parser_avctx->codec_id = ctx->codec_id;
294 
295  int got_frame;
297  if (!frame)
298  error("Failed memory allocation");
299 
300  // Read very simple container
301  AVPacket avpkt, parsepkt;
302  av_init_packet(&avpkt);
303  av_init_packet(&parsepkt);
304  while (data < end && it < maxiteration) {
305  // Search for the TAG
306  while (data + sizeof(fuzz_tag) < end) {
307  if (data[0] == (fuzz_tag & 0xFF) && AV_RN64(data) == fuzz_tag)
308  break;
309  data++;
310  }
311  if (data + sizeof(fuzz_tag) > end)
312  data = end;
313 
314  res = av_new_packet(&parsepkt, data - last);
315  if (res < 0)
316  error("Failed memory allocation");
317  memcpy(parsepkt.data, last, data - last);
318  parsepkt.flags = (keyframes & 1) * AV_PKT_FLAG_DISCARD + (!!(keyframes & 2)) * AV_PKT_FLAG_KEY;
319  keyframes = (keyframes >> 2) + (keyframes<<62);
320  data += sizeof(fuzz_tag);
321  last = data;
322 
323  while (parsepkt.size > 0) {
324  int decode_more;
325 
326  if (parser) {
327  av_init_packet(&avpkt);
328  int ret = av_parser_parse2(parser, parser_avctx, &avpkt.data, &avpkt.size,
329  parsepkt.data, parsepkt.size,
330  parsepkt.pts, parsepkt.dts, parsepkt.pos);
331  if (avpkt.data == parsepkt.data) {
332  avpkt.buf = av_buffer_ref(parsepkt.buf);
333  if (!avpkt.buf)
334  error("Failed memory allocation");
335  } else {
336  if (av_packet_make_refcounted(&avpkt) < 0)
337  error("Failed memory allocation");
338  }
339  parsepkt.data += ret;
340  parsepkt.size -= ret;
341  parsepkt.pos += ret;
342  avpkt.pts = parser->pts;
343  avpkt.dts = parser->dts;
344  avpkt.pos = parser->pos;
345  if ( parser->key_frame == 1 ||
346  (parser->key_frame == -1 && parser->pict_type == AV_PICTURE_TYPE_I))
347  avpkt.flags |= AV_PKT_FLAG_KEY;
348  avpkt.flags |= parsepkt.flags & AV_PKT_FLAG_DISCARD;
349  } else {
350  av_packet_move_ref(&avpkt, &parsepkt);
351  }
352 
353  if (!(flushpattern & 7))
355  flushpattern = (flushpattern >> 3) + (flushpattern << 61);
356 
357  if (ctx->codec_type != AVMEDIA_TYPE_SUBTITLE) {
358  int ret = avcodec_send_packet(ctx, &avpkt);
359  decode_more = ret >= 0;
360  if(!decode_more) {
361  ec_pixels += (ctx->width + 32LL) * (ctx->height + 32LL);
362  if (it > 20 || ec_pixels > 4 * ctx->max_pixels)
363  ctx->error_concealment = 0;
364  if (ec_pixels > maxpixels)
365  goto maximums_reached;
366  }
367  } else
368  decode_more = 1;
369 
370  // Iterate through all data
371  while (decode_more && it++ < maxiteration) {
372  av_frame_unref(frame);
373  int ret = decode_handler(ctx, frame, &got_frame, &avpkt);
374 
375  ec_pixels += (ctx->width + 32LL) * (ctx->height + 32LL);
376  if (it > 20 || ec_pixels > 4 * ctx->max_pixels)
377  ctx->error_concealment = 0;
378  if (ec_pixels > maxpixels)
379  goto maximums_reached;
380 
381  if (ctx->codec_type == AVMEDIA_TYPE_AUDIO &&
382  frame->nb_samples == 0 && !got_frame &&
383  (avpkt.flags & AV_PKT_FLAG_DISCARD))
384  nb_samples += ctx->max_samples;
385 
386  nb_samples += frame->nb_samples;
387  if (nb_samples > maxsamples)
388  goto maximums_reached;
389 
390  if (ret <= 0 || ret > avpkt.size)
391  break;
392 
393  if (ctx->codec_type == AVMEDIA_TYPE_SUBTITLE) {
394  avpkt.data += ret;
395  avpkt.size -= ret;
396  decode_more = avpkt.size > 0;
397  } else
398  decode_more = ret >= 0;
399  }
400  av_packet_unref(&avpkt);
401  }
402  av_packet_unref(&parsepkt);
403  }
404 maximums_reached:
405 
406  av_packet_unref(&avpkt);
407 
408  if (ctx->codec_type != AVMEDIA_TYPE_SUBTITLE)
410 
411  do {
412  got_frame = 0;
413  av_frame_unref(frame);
414  decode_handler(ctx, frame, &got_frame, &avpkt);
415  } while (got_frame == 1 && it++ < maxiteration);
416 
417  fprintf(stderr, "pixels decoded: %"PRId64", samples decoded: %"PRId64", iterations: %d\n", ec_pixels, nb_samples, it);
418 
419  av_frame_free(&frame);
420  avcodec_free_context(&ctx);
421  avcodec_free_context(&parser_avctx);
422  av_parser_close(parser);
423  av_packet_unref(&parsepkt);
424  av_dict_free(&opts);
425  return 0;
426 }
#define FF_SANE_NB_CHANNELS
Definition: internal.h:97
#define FF_COMPLIANCE_EXPERIMENTAL
Allow nonstandardized experimental things.
Definition: avcodec.h:1601
const uint32_t maxiteration
#define AV_EF_AGGRESSIVE
consider things that a sane encoder should not do as an error
Definition: avcodec.h:1656
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
uint64_t maxsamples
misc image utilities
int64_t bit_rate
the average bitrate
Definition: avcodec.h:581
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:383
void av_log_set_level(int level)
Set the log level.
Definition: log.c:440
int size
Definition: packet.h:364
#define AV_EF_COMPLIANT
consider all spec non compliances as errors
Definition: avcodec.h:1655
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
enum AVMediaType type
Definition: codec.h:203
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:1003
AVCodec.
Definition: codec.h:190
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1228
uint8_t
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
#define AV_LOG_PANIC
Something went really wrong and we will crash now.
Definition: log.h:181
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:632
uint8_t * data
Definition: packet.h:363
s EdgeDetect Foobar g libavfilter vf_edgedetect c libavfilter vf_foobar c edit libavfilter and add an entry for foobar following the pattern of the other filters edit libavfilter allfilters and add an entry for foobar following the pattern of the other filters configure make j< whatever > ffmpeg ffmpeg i you should get a foobar png with Lena edge detected That s it
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:664
ptrdiff_t size
Definition: opengl_enc.c:100
const uint32_t * codec_tags
List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
Definition: codec.h:328
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1735
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
static AVCodec * c
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:88
enum AVCodecID id
Definition: codec.h:204
static const uint64_t FUZZ_TAG
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:3446
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
int error_concealment
error concealment flags
Definition: avcodec.h:1608
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:624
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: packet.h:346
simple assert() macros that are a bit more flexible than ISO C assert().
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:2239
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:369
AVDictionary * opts
Definition: movenc.c:50
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:317
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1640
#define FFMIN(a, b)
Definition: common.h:105
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:172
int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int64_t pts, int64_t dts, int64_t pos)
Parse a packet.
Definition: parser.c:120
static AVCodec * AVCodecInitialize(enum AVCodecID codec_id)
int width
picture width / height.
Definition: avcodec.h:704
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1714
int av_packet_make_refcounted(AVPacket *pkt)
Ensure the data described by a given packet is reference counted.
Definition: avpacket.c:672
AVFormatContext * ctx
Definition: movenc.c:48
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:224
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:1651
int dummy
Definition: motion.c:64
enum AVCodecID codec_id
Definition: vaapi_decode.c:369
static void error(const char *err)
static int subtitle_handler(AVCodecContext *avctx, void *frame, int *got_sub_ptr, AVPacket *avpkt)
if(ret)
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: utils.c:1093
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:561
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:34
Libavcodec external API header.
enum AVMediaType codec_type
Definition: avcodec.h:539
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer...
Definition: options.c:187
enum AVCodecID codec_id
Definition: avcodec.h:541
int sample_rate
samples per second
Definition: avcodec.h:1191
#define AV_CODEC_FLAG2_FAST
Allow non spec compliant speedup tricks.
Definition: avcodec.h:348
main external API structure.
Definition: avcodec.h:531
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:606
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: utils.c:1148
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> (&#39;D&#39;<<24) + (&#39;C&#39;<<16) + (&#39;B&#39;<<8) + &#39;A&#39;).
Definition: avcodec.h:556
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:2327
uint64_t maxpixels_per_frame
int extradata_size
Definition: avcodec.h:633
#define AV_EF_CAREFUL
consider things that violate the spec, are fast to calculate and have not been seen in the wild as er...
Definition: avcodec.h:1654
static int audio_video_handler(AVCodecContext *avctx, AVFrame *frame, int *got_frame, const AVPacket *dummy)
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:545
AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
Definition: allcodecs.c:943
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
#define flags(name, subs,...)
Definition: cbs_av1.c:561
Main libavformat public API header.
int
#define AV_PKT_FLAG_DISCARD
Flag is used to discard packets which are required to maintain valid decoder state but are not requir...
Definition: packet.h:408
common internal api header.
int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags)
Convenience wrapper for av_dict_set that converts the value to a string and stores it...
Definition: dict.c:147
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:35
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:215
#define av_free(p)
uint64_t maxpixels
int channels
number of audio channels
Definition: avcodec.h:1192
#define AV_RN64(p)
Definition: intreadwrite.h:368
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:618
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: packet.h:362
static float sub(float src0, float src1)
#define FF_CODEC_TAGS_END
AVCodec.codec_tags termination value.
Definition: internal.h:80
void av_force_cpu_flags(int arg)
Disables cpu detection and forces the specified flags.
Definition: cpu.c:67
uint64_t maxsamples_per_frame
uint64_t request_channel_layout
Request decoder to use this channel layout if it can (0 for default)
Definition: avcodec.h:1249
This structure stores compressed data.
Definition: packet.h:340
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:3385
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:380
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1596
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:356
AVCodec * codec_list[]