FFmpeg  4.3.8
options.c
Go to the documentation of this file.
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 && avc->codec->name)
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 static const AVClass *codec_child_class_next(const AVClass *prev)
57 {
58  void *iter = NULL;
59  const AVCodec *c = NULL;
60 
61  /* find the codec that corresponds to prev */
62  while (prev && (c = av_codec_iterate(&iter)))
63  if (c->priv_class == prev)
64  break;
65 
66  /* find next codec with priv options */
67  while (c = av_codec_iterate(&iter))
68  if (c->priv_class)
69  return c->priv_class;
70  return NULL;
71 }
72 
73 static AVClassCategory get_category(void *ptr)
74 {
75  AVCodecContext* avctx = ptr;
76  if(avctx->codec && avctx->codec->decode) return AV_CLASS_CATEGORY_DECODER;
77  else return AV_CLASS_CATEGORY_ENCODER;
78 }
79 
81  .class_name = "AVCodecContext",
82  .item_name = context_to_name,
83  .option = avcodec_options,
84  .version = LIBAVUTIL_VERSION_INT,
85  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
86  .child_next = codec_child_next,
87  .child_class_next = codec_child_class_next,
89  .get_category = get_category,
90 };
91 
92 static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
93 {
94  int flags=0;
95  memset(s, 0, sizeof(AVCodecContext));
96 
98 
99  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
100  if (codec) {
101  s->codec = codec;
102  s->codec_id = codec->id;
103  }
104 
107  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
109  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
111  av_opt_set_defaults2(s, flags, flags);
112 
113  s->time_base = (AVRational){0,1};
114  s->framerate = (AVRational){ 0, 1 };
115  s->pkt_timebase = (AVRational){ 0, 1 };
120  s->sample_aspect_ratio = (AVRational){0,1};
124 
126  if(codec && codec->priv_data_size){
127  if(!s->priv_data){
128  s->priv_data= av_mallocz(codec->priv_data_size);
129  if (!s->priv_data) {
130  return AVERROR(ENOMEM);
131  }
132  }
133  if(codec->priv_class){
134  *(const AVClass**)s->priv_data = codec->priv_class;
136  }
137  }
138  if (codec && codec->defaults) {
139  int ret;
140  const AVCodecDefault *d = codec->defaults;
141  while (d->key) {
142  ret = av_opt_set(s, d->key, d->value, 0);
143  av_assert0(ret >= 0);
144  d++;
145  }
146  }
147  return 0;
148 }
149 
150 #if FF_API_GET_CONTEXT_DEFAULTS
152 {
153  return init_context_defaults(s, codec);
154 }
155 #endif
156 
158 {
159  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
160 
161  if (!avctx)
162  return NULL;
163 
164  if (init_context_defaults(avctx, codec) < 0) {
165  av_free(avctx);
166  return NULL;
167  }
168 
169  return avctx;
170 }
171 
173 {
174  AVCodecContext *avctx = *pavctx;
175 
176  if (!avctx)
177  return;
178 
179  avcodec_close(avctx);
180 
181  av_freep(&avctx->extradata);
182  av_freep(&avctx->subtitle_header);
183  av_freep(&avctx->intra_matrix);
184  av_freep(&avctx->inter_matrix);
185  av_freep(&avctx->rc_override);
186 
187  av_freep(pavctx);
188 }
189 
190 #if FF_API_COPY_CONTEXT
192 {
193  int i;
194 
195  av_opt_free(avctx);
196 #if FF_API_CODED_FRAME
198  av_frame_free(&avctx->coded_frame);
200 #endif
201  av_freep(&avctx->rc_override);
202  av_freep(&avctx->intra_matrix);
203  av_freep(&avctx->inter_matrix);
204  av_freep(&avctx->extradata);
205  av_freep(&avctx->subtitle_header);
208  for (i = 0; i < avctx->nb_coded_side_data; i++)
209  av_freep(&avctx->coded_side_data[i].data);
210  av_freep(&avctx->coded_side_data);
211  avctx->subtitle_header_size = 0;
212  avctx->nb_coded_side_data = 0;
213  avctx->extradata_size = 0;
214 }
215 
217 {
218  const AVCodec *orig_codec = dest->codec;
219  uint8_t *orig_priv_data = dest->priv_data;
220 
221  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
222  av_log(dest, AV_LOG_ERROR,
223  "Tried to copy AVCodecContext %p into already-initialized %p\n",
224  src, dest);
225  return AVERROR(EINVAL);
226  }
227 
228  copy_context_reset(dest);
229 
230  memcpy(dest, src, sizeof(*dest));
231  av_opt_copy(dest, src);
232 
233  dest->priv_data = orig_priv_data;
234  dest->codec = orig_codec;
235 
236  if (orig_priv_data && src->codec && src->codec->priv_class &&
237  dest->codec && dest->codec->priv_class)
238  av_opt_copy(orig_priv_data, src->priv_data);
239 
240 
241  /* set values specific to opened codecs back to their default state */
242  dest->slice_offset = NULL;
243  dest->hwaccel = NULL;
244  dest->internal = NULL;
245 #if FF_API_CODED_FRAME
247  dest->coded_frame = NULL;
249 #endif
250 
251  /* reallocate values that should be allocated separately */
252  dest->extradata = NULL;
253  dest->coded_side_data = NULL;
254  dest->intra_matrix = NULL;
255  dest->inter_matrix = NULL;
256  dest->rc_override = NULL;
257  dest->subtitle_header = NULL;
258  dest->hw_frames_ctx = NULL;
259  dest->hw_device_ctx = NULL;
260  dest->nb_coded_side_data = 0;
261 
262 #define alloc_and_copy_or_fail(obj, size, pad) \
263  if (src->obj && size > 0) { \
264  dest->obj = av_malloc(size + pad); \
265  if (!dest->obj) \
266  goto fail; \
267  memcpy(dest->obj, src->obj, size); \
268  if (pad) \
269  memset(((uint8_t *) dest->obj) + size, 0, pad); \
270  }
271  alloc_and_copy_or_fail(extradata, src->extradata_size,
273  dest->extradata_size = src->extradata_size;
274  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
275  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
276  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
277  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
279 #undef alloc_and_copy_or_fail
280 
281  if (src->hw_frames_ctx) {
283  if (!dest->hw_frames_ctx)
284  goto fail;
285  }
286 
287  return 0;
288 
289 fail:
290  copy_context_reset(dest);
291  return AVERROR(ENOMEM);
292 }
293 #endif
294 
296 {
297  return &av_codec_context_class;
298 }
299 
300 #define FOFFSET(x) offsetof(AVFrame,x)
301 
302 static const AVOption frame_options[]={
303 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
304 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
305 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
306 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
307 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
308 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
309 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
310 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
311 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
312 {NULL},
313 };
314 
315 static const AVClass av_frame_class = {
316  .class_name = "AVFrame",
317  .item_name = NULL,
318  .option = frame_options,
319  .version = LIBAVUTIL_VERSION_INT,
320 };
321 
323 {
324  return &av_frame_class;
325 }
326 
327 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
328 
330 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
331 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
332 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
333 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
334 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
335 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
336 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
337 {NULL},
338 };
339 
341  .class_name = "AVSubtitleRect",
342  .item_name = NULL,
343  .option = subtitle_rect_options,
344  .version = LIBAVUTIL_VERSION_INT,
345 };
346 
348 {
349  return &av_subtitle_rect_class;
350 }
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:778
#define NULL
Definition: coverity.c:32
const struct AVCodec * codec
Definition: avcodec.h:535
AVRational framerate
Definition: avcodec.h:2069
static const char * format[]
Definition: af_aiir.c:339
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
int avcodec_default_execute2(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int, int), void *arg, int *ret, int count)
AVOption.
Definition: opt.h:246
#define AV_OPT_FLAG_SUBTITLE_PARAM
Definition: opt.h:280
#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:1357
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:278
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:905
static const AVOption avcodec_options[]
Definition: options_table.h:45
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
enum AVMediaType type
Definition: codec.h:203
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1690
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
Definition: allcodecs.c:832
AVCodec.
Definition: codec.h:190
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:649
static void copy_context_reset(AVCodecContext *avctx)
Definition: options.c:191
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:295
static const AVClass av_codec_context_class
Definition: options.c:80
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:92
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:1067
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1194
uint8_t
#define av_malloc(s)
static const AVOption subtitle_rect_options[]
Definition: options.c:329
AVOptions.
int subtitle_header_size
Definition: avcodec.h:2015
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:627
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:531
static const AVClass av_subtitle_rect_class
Definition: options.c:340
#define height
uint8_t * data
Definition: packet.h:299
const AVClass * avcodec_get_frame_class(void)
Get the AVClass for AVFrame.
Definition: options.c:322
#define av_log(a,...)
#define src
Definition: vp8dsp.c:254
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: utils.c:1152
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:2083
enum AVCodecID id
Definition: codec.h:204
const AVCodecDefault * defaults
Private codec-specific defaults.
Definition: codec.h:257
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
int avcodec_is_open(AVCodecContext *s)
Definition: utils.c:1971
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().
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 char * name
Name of the codec implementation.
Definition: codec.h:197
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:130
#define fail()
Definition: checkasm.h:123
common internal API header
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1396
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:2201
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
Copy the settings of the source AVCodecContext into the destination AVCodecContext.
Definition: options.c:216
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:157
#define width
uint8_t w
Definition: llviddspenc.c:38
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:2226
int priv_data_size
Definition: codec.h:238
static const AVClass * codec_child_class_next(const AVClass *prev)
Definition: options.c:56
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:347
#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:1362
int64_t reordered_opaque
opaque 64-bit number (generally a PTS) that will be reordered and output in AVFrame.reordered_opaque
Definition: avcodec.h:1683
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:200
RcOverride * rc_override
Definition: avcodec.h:1397
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:1845
int(* decode)(struct AVCodecContext *, void *outdata, int *outdata_size, struct AVPacket *avpkt)
Definition: codec.h:282
sample_rate
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: decode.c:1649
#define SROFFSET(x)
Definition: options.c:327
Libavcodec external API header.
enum AVMediaType codec_type
Definition: avcodec.h:534
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:172
enum AVCodecID codec_id
Definition: avcodec.h:536
#define AV_OPT_FLAG_VIDEO_PARAM
Definition: opt.h:279
main external API structure.
Definition: avcodec.h:526
int extradata_size
Definition: avcodec.h:628
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions...
Definition: avcodec.h:1026
int nb_coded_side_data
Definition: avcodec.h:2202
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:1341
Rational number (pair of numerator and denominator).
Definition: rational.h:58
cl_device_type type
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions...
Definition: avcodec.h:1035
#define flags(name, subs,...)
Definition: cbs_av1.c:576
const AVClass * priv_class
AVClass for the private context.
Definition: codec.h:216
const uint8_t * key
Definition: internal.h:202
const uint8_t * value
Definition: internal.h:203
void av_opt_free(void *obj)
Free all allocated objects in obj.
Definition: opt.c:1610
static const AVOption frame_options[]
Definition: options.c:302
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
common internal api header.
static double c[64]
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:1768
static AVClassCategory get_category(void *ptr)
Definition: options.c:73
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:1776
static const AVClass av_frame_class
Definition: options.c:315
int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:151
#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:553
#define av_free(p)
AVClassCategory
Definition: log.h:29
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:85
#define alloc_and_copy_or_fail(obj, size, pad)
struct AVCodecInternal * internal
Private context used for internal data.
Definition: avcodec.h:561
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:896
#define av_freep(p)
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:2278
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:1825
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:2076
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
#define FOFFSET(x)
Definition: options.c:300
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: utils.c:460
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:2014