FFmpeg
options.c
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1 /*
2  * Copyright (c) 2001 Fabrice Bellard
3  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Options definition for AVCodecContext.
25  */
26 
27 #include "avcodec.h"
28 #include "internal.h"
29 #include "libavutil/avassert.h"
30 #include "libavutil/internal.h"
31 #include "libavutil/mem.h"
32 #include "libavutil/opt.h"
33 #include <string.h>
34 
36 #include "options_table.h"
38 
39 static const char* context_to_name(void* ptr) {
40  AVCodecContext *avc= ptr;
41 
42  if (avc && avc->codec)
43  return avc->codec->name;
44  else
45  return "NULL";
46 }
47 
48 static void *codec_child_next(void *obj, void *prev)
49 {
50  AVCodecContext *s = obj;
51  if (!prev && s->codec && s->codec->priv_class && s->priv_data)
52  return s->priv_data;
53  return NULL;
54 }
55 
56 #if FF_API_CHILD_CLASS_NEXT
57 static const AVClass *codec_child_class_next(const AVClass *prev)
58 {
59  void *iter = NULL;
60  const AVCodec *c = NULL;
61 
62  /* find the codec that corresponds to prev */
63  while (prev && (c = av_codec_iterate(&iter)))
64  if (c->priv_class == prev)
65  break;
66 
67  /* find next codec with priv options */
68  while (c = av_codec_iterate(&iter))
69  if (c->priv_class)
70  return c->priv_class;
71  return NULL;
72 }
73 #endif
74 
75 static const AVClass *codec_child_class_iterate(void **iter)
76 {
77  const AVCodec *c;
78  /* find next codec with priv options */
79  while (c = av_codec_iterate(iter))
80  if (c->priv_class)
81  return c->priv_class;
82  return NULL;
83 }
84 
85 static AVClassCategory get_category(void *ptr)
86 {
87  AVCodecContext* avctx = ptr;
88  if(avctx->codec && avctx->codec->decode) return AV_CLASS_CATEGORY_DECODER;
89  else return AV_CLASS_CATEGORY_ENCODER;
90 }
91 
93  .class_name = "AVCodecContext",
94  .item_name = context_to_name,
95  .option = avcodec_options,
96  .version = LIBAVUTIL_VERSION_INT,
97  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
98  .child_next = codec_child_next,
99 #if FF_API_CHILD_CLASS_NEXT
100  .child_class_next = codec_child_class_next,
101 #endif
102  .child_class_iterate = codec_child_class_iterate,
104  .get_category = get_category,
105 };
106 
107 static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
108 {
109  int flags=0;
110  memset(s, 0, sizeof(AVCodecContext));
111 
113 
114  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
115  if (codec) {
116  s->codec = codec;
117  s->codec_id = codec->id;
118  }
119 
122  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
124  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
126  av_opt_set_defaults2(s, flags, flags);
127 
128  s->time_base = (AVRational){0,1};
129  s->framerate = (AVRational){ 0, 1 };
130  s->pkt_timebase = (AVRational){ 0, 1 };
136  s->sample_aspect_ratio = (AVRational){0,1};
140 
142  if(codec && codec->priv_data_size){
143  s->priv_data = av_mallocz(codec->priv_data_size);
144  if (!s->priv_data)
145  return AVERROR(ENOMEM);
146  if(codec->priv_class){
147  *(const AVClass**)s->priv_data = codec->priv_class;
149  }
150  }
151  if (codec && codec->defaults) {
152  int ret;
153  const AVCodecDefault *d = codec->defaults;
154  while (d->key) {
155  ret = av_opt_set(s, d->key, d->value, 0);
156  av_assert0(ret >= 0);
157  d++;
158  }
159  }
160  return 0;
161 }
162 
163 #if FF_API_GET_CONTEXT_DEFAULTS
165 {
166  return init_context_defaults(s, codec);
167 }
168 #endif
169 
171 {
172  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
173 
174  if (!avctx)
175  return NULL;
176 
177  if (init_context_defaults(avctx, codec) < 0) {
178  av_free(avctx);
179  return NULL;
180  }
181 
182  return avctx;
183 }
184 
186 {
187  AVCodecContext *avctx = *pavctx;
188 
189  if (!avctx)
190  return;
191 
192  avcodec_close(avctx);
193 
194  av_freep(&avctx->extradata);
195  av_freep(&avctx->subtitle_header);
196  av_freep(&avctx->intra_matrix);
197  av_freep(&avctx->inter_matrix);
198  av_freep(&avctx->rc_override);
199 
200  av_freep(pavctx);
201 }
202 
203 #if FF_API_COPY_CONTEXT
205 {
206  int i;
207 
208  av_opt_free(avctx);
209 #if FF_API_CODED_FRAME
211  av_frame_free(&avctx->coded_frame);
213 #endif
214  av_freep(&avctx->rc_override);
215  av_freep(&avctx->intra_matrix);
216  av_freep(&avctx->inter_matrix);
217  av_freep(&avctx->extradata);
218  av_freep(&avctx->subtitle_header);
221  for (i = 0; i < avctx->nb_coded_side_data; i++)
222  av_freep(&avctx->coded_side_data[i].data);
223  av_freep(&avctx->coded_side_data);
224  avctx->subtitle_header_size = 0;
225  avctx->nb_coded_side_data = 0;
226  avctx->extradata_size = 0;
227 }
228 
230 {
231  const AVCodec *orig_codec = dest->codec;
232  uint8_t *orig_priv_data = dest->priv_data;
233 
234  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
235  av_log(dest, AV_LOG_ERROR,
236  "Tried to copy AVCodecContext %p into already-initialized %p\n",
237  src, dest);
238  return AVERROR(EINVAL);
239  }
240 
241  copy_context_reset(dest);
242 
243  memcpy(dest, src, sizeof(*dest));
244  av_opt_copy(dest, src);
245 
246  dest->priv_data = orig_priv_data;
247  dest->codec = orig_codec;
248 
249  if (orig_priv_data && src->codec && src->codec->priv_class &&
250  dest->codec && dest->codec->priv_class)
251  av_opt_copy(orig_priv_data, src->priv_data);
252 
253 
254  /* set values specific to opened codecs back to their default state */
255  dest->slice_offset = NULL;
256  dest->hwaccel = NULL;
257  dest->internal = NULL;
258 #if FF_API_CODED_FRAME
260  dest->coded_frame = NULL;
262 #endif
263 
264  /* reallocate values that should be allocated separately */
265  dest->extradata = NULL;
266  dest->coded_side_data = NULL;
267  dest->intra_matrix = NULL;
268  dest->inter_matrix = NULL;
269  dest->rc_override = NULL;
270  dest->subtitle_header = NULL;
271  dest->hw_frames_ctx = NULL;
272  dest->hw_device_ctx = NULL;
273  dest->nb_coded_side_data = 0;
274 
275 #define alloc_and_copy_or_fail(obj, size, pad) \
276  if (src->obj && size > 0) { \
277  dest->obj = av_malloc(size + pad); \
278  if (!dest->obj) \
279  goto fail; \
280  memcpy(dest->obj, src->obj, size); \
281  if (pad) \
282  memset(((uint8_t *) dest->obj) + size, 0, pad); \
283  }
284  alloc_and_copy_or_fail(extradata, src->extradata_size,
286  dest->extradata_size = src->extradata_size;
287  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
288  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
289  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
290  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
292 #undef alloc_and_copy_or_fail
293 
294  if (src->hw_frames_ctx) {
296  if (!dest->hw_frames_ctx)
297  goto fail;
298  }
299 
300  return 0;
301 
302 fail:
303  copy_context_reset(dest);
304  return AVERROR(ENOMEM);
305 }
306 #endif
307 
309 {
310  return &av_codec_context_class;
311 }
312 
313 #if FF_API_GET_FRAME_CLASS
314 #define FOFFSET(x) offsetof(AVFrame,x)
315 
316 static const AVOption frame_options[]={
317 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
318 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
319 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
320 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
321 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
322 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
323 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
324 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
325 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
326 {NULL},
327 };
328 
329 static const AVClass av_frame_class = {
330  .class_name = "AVFrame",
331  .item_name = NULL,
332  .option = frame_options,
333  .version = LIBAVUTIL_VERSION_INT,
334 };
335 
337 {
338  return &av_frame_class;
339 }
340 #endif
341 
342 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
343 
345 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
346 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
347 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
348 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
349 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
350 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
351 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
352 {NULL},
353 };
354 
356  .class_name = "AVSubtitleRect",
357  .item_name = NULL,
358  .option = subtitle_rect_options,
359  .version = LIBAVUTIL_VERSION_INT,
360 };
361 
363 {
364  return &av_subtitle_rect_class;
365 }
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:788
fg outputs[0] format
#define NULL
Definition: coverity.c:32
const struct AVCodec * codec
Definition: avcodec.h:545
AVRational framerate
Definition: avcodec.h:2071
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it...
Definition: buffer.c:125
AVOption.
Definition: opt.h:248
#define AV_OPT_FLAG_SUBTITLE_PARAM
Definition: opt.h:282
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
Memory handling functions.
void av_opt_set_defaults(void *s)
Set the values of all AVOption fields to their default values.
Definition: opt.c:1358
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:280
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel...
Definition: avcodec.h:915
static const AVOption avcodec_options[]
Definition: options_table.h:45
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
GLint GLenum type
Definition: opengl_enc.c:104
enum AVMediaType type
Definition: codec.h:210
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
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1680
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
Definition: allcodecs.c:859
AVCodec.
Definition: codec.h:197
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:659
static void copy_context_reset(AVCodecContext *avctx)
Definition: options.c:204
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:308
static const AVClass av_codec_context_class
Definition: options.c:92
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:107
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:1105
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1204
uint8_t
#define av_malloc(s)
static const AVOption subtitle_rect_options[]
Definition: options.c:344
AVOptions.
int subtitle_header_size
Definition: avcodec.h:2017
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:637
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:541
static const AVClass av_subtitle_rect_class
Definition: options.c:355
#define height
uint8_t * data
Definition: packet.h:307
#define av_log(a,...)
const AVClass * avcodec_get_frame_class(void)
Definition: options.c:336
#define src
Definition: vp8dsp.c:255
av_cold int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: avcodec.c:523
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:2085
enum AVCodecID id
Definition: codec.h:211
const AVCodecDefault * defaults
Private codec-specific defaults.
Definition: codec.h:266
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:204
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:796
static void * codec_child_next(void *obj, void *prev)
Definition: options.c:48
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
Definition: codec.h:204
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:133
#define fail()
Definition: checkasm.h:133
common internal API header
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1408
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:2193
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
Copy the settings of the source AVCodecContext into the destination AVCodecContext.
Definition: options.c:229
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:170
static const AVClass * codec_child_class_iterate(void **iter)
Definition: options.c:75
#define width
uint8_t w
Definition: llviddspenc.c:39
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:2218
int priv_data_size
Definition: codec.h:245
int avcodec_default_execute2(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int jobnr, int threadnr), void *arg, int *ret, int count)
Definition: avcodec.c:78
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:362
#define s(width, name)
Definition: cbs_vp9.c:257
void av_opt_set_defaults2(void *s, int mask, int flags)
Set the values of all AVOption fields to their default values.
Definition: opt.c:1363
int64_t reordered_opaque
opaque 64-bit number (generally a PTS) that will be reordered and output in AVFrame.reordered_opaque
Definition: avcodec.h:1673
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:200
RcOverride * rc_override
Definition: avcodec.h:1409
int(* decode)(struct AVCodecContext *avctx, void *outdata, int *got_frame_ptr, struct AVPacket *avpkt)
Decode picture or subtitle data.
Definition: codec.h:303
int(* execute2)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count)
The codec may call this to execute several independent things.
Definition: avcodec.h:1844
sample_rate
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: decode.c:1686
#define SROFFSET(x)
Definition: options.c:342
Libavcodec external API header.
enum AVMediaType codec_type
Definition: avcodec.h:544
void avcodec_free_context(AVCodecContext **pavctx)
Free the codec context and everything associated with it and write NULL to the provided pointer...
Definition: options.c:185
enum AVCodecID codec_id
Definition: avcodec.h:546
#define AV_OPT_FLAG_VIDEO_PARAM
Definition: opt.h:281
main external API structure.
Definition: avcodec.h:536
int extradata_size
Definition: avcodec.h:638
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions...
Definition: avcodec.h:1036
int nb_coded_side_data
Definition: avcodec.h:2194
Describe the class of an AVClass context structure.
Definition: log.h:67
int(* get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags)
This callback is called at the beginning of each frame to get data buffer(s) for it.
Definition: avcodec.h:1351
Rational number (pair of numerator and denominator).
Definition: rational.h:58
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions...
Definition: avcodec.h:1045
#define flags(name, subs,...)
Definition: cbs_av1.c:561
const AVClass * priv_class
AVClass for the private context.
Definition: codec.h:223
const uint8_t * key
Definition: internal.h:218
const uint8_t * value
Definition: internal.h:219
void av_opt_free(void *obj)
Free all allocated objects in obj.
Definition: opt.c:1611
static const AVOption frame_options[]
Definition: options.c:316
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:83
common internal api header.
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
int av_opt_copy(void *dst, const void *src)
Copy options from src object into dest object.
Definition: opt.c:1789
static AVClassCategory get_category(void *ptr)
Definition: options.c:85
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:1764
static const AVClass av_frame_class
Definition: options.c:329
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:59
int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:164
#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
void * priv_data
Definition: avcodec.h:563
#define av_free(p)
AVClassCategory
Definition: log.h:29
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
#define alloc_and_copy_or_fail(obj, size, pad)
struct AVCodecInternal * internal
Private context used for internal data.
Definition: avcodec.h:571
FF_DISABLE_DEPRECATION_WARNINGS static FF_ENABLE_DEPRECATION_WARNINGS const char * context_to_name(void *ptr)
Definition: options.c:39
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:906
#define av_freep(p)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:2270
int(* execute)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size)
The codec may call this to execute several independent things.
Definition: avcodec.h:1824
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:465
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:2078
int(* get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags)
This callback is called at the beginning of each packet to get a data buffer for it.
Definition: avcodec.h:2384
int i
Definition: input.c:407
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
#define FOFFSET(x)
Definition: options.c:314
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:65
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:2016