FFmpeg  4.4.4
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 #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
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 
112  s->av_class = &av_codec_context_class;
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 
120  if(s->codec_type == AVMEDIA_TYPE_AUDIO)
122  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
124  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
127 
128  s->time_base = (AVRational){0,1};
129  s->framerate = (AVRational){ 0, 1 };
130  s->pkt_timebase = (AVRational){ 0, 1 };
131  s->get_buffer2 = avcodec_default_get_buffer2;
132  s->get_format = avcodec_default_get_format;
133  s->get_encode_buffer = avcodec_default_get_encode_buffer;
134  s->execute = avcodec_default_execute;
135  s->execute2 = avcodec_default_execute2;
136  s->sample_aspect_ratio = (AVRational){0,1};
137  s->pix_fmt = AV_PIX_FMT_NONE;
138  s->sw_pix_fmt = AV_PIX_FMT_NONE;
139  s->sample_fmt = AV_SAMPLE_FMT_NONE;
140 
141  s->reordered_opaque = AV_NOPTS_VALUE;
142  if(codec && codec->priv_data_size){
143  if(!s->priv_data){
144  s->priv_data= av_mallocz(codec->priv_data_size);
145  if (!s->priv_data) {
146  return AVERROR(ENOMEM);
147  }
148  }
149  if(codec->priv_class){
150  *(const AVClass**)s->priv_data = codec->priv_class;
151  av_opt_set_defaults(s->priv_data);
152  }
153  }
154  if (codec && codec->defaults) {
155  int ret;
156  const AVCodecDefault *d = codec->defaults;
157  while (d->key) {
158  ret = av_opt_set(s, d->key, d->value, 0);
159  av_assert0(ret >= 0);
160  d++;
161  }
162  }
163  return 0;
164 }
165 
166 #if FF_API_GET_CONTEXT_DEFAULTS
168 {
169  return init_context_defaults(s, codec);
170 }
171 #endif
172 
174 {
175  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
176 
177  if (!avctx)
178  return NULL;
179 
180  if (init_context_defaults(avctx, codec) < 0) {
181  av_free(avctx);
182  return NULL;
183  }
184 
185  return avctx;
186 }
187 
189 {
190  AVCodecContext *avctx = *pavctx;
191 
192  if (!avctx)
193  return;
194 
195  avcodec_close(avctx);
196 
197  av_freep(&avctx->extradata);
198  av_freep(&avctx->subtitle_header);
199  av_freep(&avctx->intra_matrix);
200  av_freep(&avctx->inter_matrix);
201  av_freep(&avctx->rc_override);
202 
203  av_freep(pavctx);
204 }
205 
206 #if FF_API_COPY_CONTEXT
208 {
209  int i;
210 
211  av_opt_free(avctx);
212 #if FF_API_CODED_FRAME
214  av_frame_free(&avctx->coded_frame);
216 #endif
217  av_freep(&avctx->rc_override);
218  av_freep(&avctx->intra_matrix);
219  av_freep(&avctx->inter_matrix);
220  av_freep(&avctx->extradata);
221  av_freep(&avctx->subtitle_header);
224  for (i = 0; i < avctx->nb_coded_side_data; i++)
225  av_freep(&avctx->coded_side_data[i].data);
226  av_freep(&avctx->coded_side_data);
227  avctx->subtitle_header_size = 0;
228  avctx->nb_coded_side_data = 0;
229  avctx->extradata_size = 0;
230 }
231 
233 {
234  const AVCodec *orig_codec = dest->codec;
235  uint8_t *orig_priv_data = dest->priv_data;
236 
237  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
238  av_log(dest, AV_LOG_ERROR,
239  "Tried to copy AVCodecContext %p into already-initialized %p\n",
240  src, dest);
241  return AVERROR(EINVAL);
242  }
243 
244  copy_context_reset(dest);
245 
246  memcpy(dest, src, sizeof(*dest));
247  av_opt_copy(dest, src);
248 
249  dest->priv_data = orig_priv_data;
250  dest->codec = orig_codec;
251 
252  if (orig_priv_data && src->codec && src->codec->priv_class &&
253  dest->codec && dest->codec->priv_class)
254  av_opt_copy(orig_priv_data, src->priv_data);
255 
256 
257  /* set values specific to opened codecs back to their default state */
258  dest->slice_offset = NULL;
259  dest->hwaccel = NULL;
260  dest->internal = NULL;
261 #if FF_API_CODED_FRAME
263  dest->coded_frame = NULL;
265 #endif
266 
267  /* reallocate values that should be allocated separately */
268  dest->extradata = NULL;
269  dest->coded_side_data = NULL;
270  dest->intra_matrix = NULL;
271  dest->inter_matrix = NULL;
272  dest->rc_override = NULL;
273  dest->subtitle_header = NULL;
274  dest->hw_frames_ctx = NULL;
275  dest->hw_device_ctx = NULL;
276  dest->nb_coded_side_data = 0;
277 
278 #define alloc_and_copy_or_fail(obj, size, pad) \
279  if (src->obj && size > 0) { \
280  dest->obj = av_malloc(size + pad); \
281  if (!dest->obj) \
282  goto fail; \
283  memcpy(dest->obj, src->obj, size); \
284  if (pad) \
285  memset(((uint8_t *) dest->obj) + size, 0, pad); \
286  }
287  alloc_and_copy_or_fail(extradata, src->extradata_size,
289  dest->extradata_size = src->extradata_size;
290  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
291  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
292  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
293  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
294  av_assert0(dest->subtitle_header_size == src->subtitle_header_size);
295 #undef alloc_and_copy_or_fail
296 
297  if (src->hw_frames_ctx) {
298  dest->hw_frames_ctx = av_buffer_ref(src->hw_frames_ctx);
299  if (!dest->hw_frames_ctx)
300  goto fail;
301  }
302 
303  return 0;
304 
305 fail:
306  copy_context_reset(dest);
307  return AVERROR(ENOMEM);
308 }
309 #endif
310 
312 {
313  return &av_codec_context_class;
314 }
315 
316 #if FF_API_GET_FRAME_CLASS
317 #define FOFFSET(x) offsetof(AVFrame,x)
318 
319 static const AVOption frame_options[]={
320 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
321 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
322 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
323 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
324 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
325 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
326 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
327 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
328 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
329 {NULL},
330 };
331 
332 static const AVClass av_frame_class = {
333  .class_name = "AVFrame",
334  .item_name = NULL,
335  .option = frame_options,
336  .version = LIBAVUTIL_VERSION_INT,
337 };
338 
340 {
341  return &av_frame_class;
342 }
343 #endif
344 
345 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
346 
348 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
349 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
350 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
351 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
352 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
353 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
354 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
355 {NULL},
356 };
357 
359  .class_name = "AVSubtitleRect",
360  .item_name = NULL,
361  .option = subtitle_rect_options,
362  .version = LIBAVUTIL_VERSION_INT,
363 };
364 
366 {
367  return &av_subtitle_rect_class;
368 }
static const char *const format[]
Definition: af_aiir.c:456
uint8_t
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
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:80
Libavcodec external API header.
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define fail()
Definition: checkasm.h:133
#define NULL
Definition: coverity.c:32
sample_rate
int av_opt_copy(void *dst, const void *src)
Copy options from src object into dest object.
Definition: opt.c:1789
void av_opt_free(void *obj)
Free all allocated objects in obj.
Definition: opt.c:1611
void av_opt_set_defaults(void *s)
Set the values of all AVOption fields to their default values.
Definition: opt.c:1358
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
@ AV_OPT_TYPE_RATIONAL
Definition: opt.h:230
@ AV_OPT_TYPE_FLAGS
Definition: opt.h:224
@ AV_OPT_TYPE_INT64
Definition: opt.h:226
@ AV_OPT_TYPE_INT
Definition: opt.h:225
const AVClass * avcodec_get_frame_class(void)
Definition: options.c:339
int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:167
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:365
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
Definition: allcodecs.c:859
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
Copy the settings of the source AVCodecContext into the destination AVCodecContext.
Definition: options.c:232
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:173
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:311
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:570
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:188
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: decode.c:1695
#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
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:59
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:1114
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:848
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:67
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
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
#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
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
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
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
@ AVMEDIA_TYPE_UNKNOWN
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:200
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:465
cl_device_type type
int i
Definition: input.c:407
#define SROFFSET(x)
Definition: options.c:345
static const AVClass av_subtitle_rect_class
Definition: options.c:358
static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:107
FF_DISABLE_DEPRECATION_WARNINGS static FF_ENABLE_DEPRECATION_WARNINGS const char * context_to_name(void *ptr)
Definition: options.c:39
static const AVClass * codec_child_class_iterate(void **iter)
Definition: options.c:75
static const AVClass * codec_child_class_next(const AVClass *prev)
Definition: options.c:57
static const AVOption frame_options[]
Definition: options.c:319
#define alloc_and_copy_or_fail(obj, size, pad)
static void * codec_child_next(void *obj, void *prev)
Definition: options.c:48
static const AVClass av_codec_context_class
Definition: options.c:92
static AVClassCategory get_category(void *ptr)
Definition: options.c:85
static void copy_context_reset(AVCodecContext *avctx)
Definition: options.c:207
#define FOFFSET(x)
Definition: options.c:317
static const AVOption subtitle_rect_options[]
Definition: options.c:347
static const AVClass av_frame_class
Definition: options.c:332
static const AVOption avcodec_options[]
Definition: options_table.h:45
common internal API header
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:83
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
uint8_t w
Definition: llviddspenc.c:39
AVClassCategory
Definition: log.h:29
@ AV_CLASS_CATEGORY_ENCODER
Definition: log.h:35
@ AV_CLASS_CATEGORY_DECODER
Definition: log.h:36
Memory handling functions.
AVOptions.
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:280
#define AV_OPT_FLAG_VIDEO_PARAM
Definition: opt.h:281
#define AV_OPT_FLAG_SUBTITLE_PARAM
Definition: opt.h:282
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
Describe the class of an AVClass context structure.
Definition: log.h:67
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:133
const struct AVClass *(* child_class_iterate)(void **iter)
Iterate over the AVClasses corresponding to potential AVOptions-enabled children.
Definition: log.h:160
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
main external API structure.
Definition: avcodec.h:536
int subtitle_header_size
Definition: avcodec.h:2017
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:2193
int nb_coded_side_data
Definition: avcodec.h:2194
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames.
Definition: avcodec.h:2218
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:1764
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:1045
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1680
const struct AVCodec * codec
Definition: avcodec.h:545
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:1036
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:2016
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:637
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
RcOverride * rc_override
Definition: avcodec.h:1409
int extradata_size
Definition: avcodec.h:638
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:906
struct AVCodecInternal * internal
Private context used for internal data.
Definition: avcodec.h:571
void * priv_data
Definition: avcodec.h:563
const uint8_t * key
Definition: internal.h:223
const uint8_t * value
Definition: internal.h:224
AVCodec.
Definition: codec.h:197
enum AVCodecID id
Definition: codec.h:211
const AVCodecDefault * defaults
Private codec-specific defaults.
Definition: codec.h:266
const AVClass * priv_class
AVClass for the private context.
Definition: codec.h:223
int(* decode)(struct AVCodecContext *avctx, void *outdata, int *got_frame_ptr, struct AVPacket *avpkt)
Decode picture or subtitle data.
Definition: codec.h:303
int priv_data_size
Definition: codec.h:245
enum AVMediaType type
Definition: codec.h:210
const char * name
Name of the codec implementation.
Definition: codec.h:204
AVOption.
Definition: opt.h:248
uint8_t * data
Definition: packet.h:307
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define av_free(p)
#define av_freep(p)
#define av_malloc(s)
#define av_log(a,...)
#define src
Definition: vp8dsp.c:255
#define height
#define width
static double c[64]