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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 <float.h> /* FLT_MIN, FLT_MAX */
34 #include <string.h>
35 
36 #include "options_table.h"
37 
38 static const char* context_to_name(void* ptr) {
39  AVCodecContext *avc= ptr;
40 
41  if(avc && avc->codec && avc->codec->name)
42  return avc->codec->name;
43  else
44  return "NULL";
45 }
46 
47 static void *codec_child_next(void *obj, void *prev)
48 {
49  AVCodecContext *s = obj;
50  if (!prev && s->codec && s->codec->priv_class && s->priv_data)
51  return s->priv_data;
52  return NULL;
53 }
54 
55 static const AVClass *codec_child_class_next(const AVClass *prev)
56 {
57  AVCodec *c = NULL;
58 
59  /* find the codec that corresponds to prev */
60  while (prev && (c = av_codec_next(c)))
61  if (c->priv_class == prev)
62  break;
63 
64  /* find next codec with priv options */
65  while (c = av_codec_next(c))
66  if (c->priv_class)
67  return c->priv_class;
68  return NULL;
69 }
70 
71 static AVClassCategory get_category(void *ptr)
72 {
73  AVCodecContext* avctx = ptr;
74  if(avctx->codec && avctx->codec->decode) return AV_CLASS_CATEGORY_DECODER;
75  else return AV_CLASS_CATEGORY_ENCODER;
76 }
77 
79  .class_name = "AVCodecContext",
80  .item_name = context_to_name,
81  .option = avcodec_options,
82  .version = LIBAVUTIL_VERSION_INT,
83  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
84  .child_next = codec_child_next,
85  .child_class_next = codec_child_class_next,
87  .get_category = get_category,
88 };
89 
91 {
92  int flags=0;
93  memset(s, 0, sizeof(AVCodecContext));
94 
96 
97  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
98  if (codec)
99  s->codec_id = codec->id;
100 
103  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
105  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
107  av_opt_set_defaults2(s, flags, flags);
108 
109  s->time_base = (AVRational){0,1};
110  s->framerate = (AVRational){ 0, 1 };
115  s->sample_aspect_ratio = (AVRational){0,1};
118  s->timecode_frame_start = -1;
119 
121  if(codec && codec->priv_data_size){
122  if(!s->priv_data){
123  s->priv_data= av_mallocz(codec->priv_data_size);
124  if (!s->priv_data) {
125  return AVERROR(ENOMEM);
126  }
127  }
128  if(codec->priv_class){
129  *(const AVClass**)s->priv_data = codec->priv_class;
131  }
132  }
133  if (codec && codec->defaults) {
134  int ret;
135  const AVCodecDefault *d = codec->defaults;
136  while (d->key) {
137  ret = av_opt_set(s, d->key, d->value, 0);
138  av_assert0(ret >= 0);
139  d++;
140  }
141  }
142  return 0;
143 }
144 
146 {
147  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
148 
149  if (!avctx)
150  return NULL;
151 
152  if(avcodec_get_context_defaults3(avctx, codec) < 0){
153  av_free(avctx);
154  return NULL;
155  }
156 
157  return avctx;
158 }
159 
161 {
162  AVCodecContext *avctx = *pavctx;
163 
164  if (!avctx)
165  return;
166 
167  avcodec_close(avctx);
168 
169  av_freep(&avctx->extradata);
170  av_freep(&avctx->subtitle_header);
171 
172  av_freep(pavctx);
173 }
174 
176 {
177  const AVCodec *orig_codec = dest->codec;
178  uint8_t *orig_priv_data = dest->priv_data;
179 
180  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
181  av_log(dest, AV_LOG_ERROR,
182  "Tried to copy AVCodecContext %p into already-initialized %p\n",
183  src, dest);
184  return AVERROR(EINVAL);
185  }
186 
187  av_opt_free(dest);
188 
189  memcpy(dest, src, sizeof(*dest));
190 
191  dest->priv_data = orig_priv_data;
192 
193  if (orig_priv_data)
194  av_opt_copy(orig_priv_data, src->priv_data);
195 
196  dest->codec = orig_codec;
197 
198  /* set values specific to opened codecs back to their default state */
199  dest->slice_offset = NULL;
200  dest->hwaccel = NULL;
201  dest->internal = NULL;
202 
203  /* reallocate values that should be allocated separately */
204  dest->extradata = NULL;
205  dest->intra_matrix = NULL;
206  dest->inter_matrix = NULL;
207  dest->rc_override = NULL;
208  dest->subtitle_header = NULL;
209 #if FF_API_MPV_OPT
211  dest->rc_eq = NULL;
212  if (src->rc_eq) {
213  dest->rc_eq = av_strdup(src->rc_eq);
214  if (!dest->rc_eq)
215  return AVERROR(ENOMEM);
216  }
218 #endif
219 
220 #define alloc_and_copy_or_fail(obj, size, pad) \
221  if (src->obj && size > 0) { \
222  dest->obj = av_malloc(size + pad); \
223  if (!dest->obj) \
224  goto fail; \
225  memcpy(dest->obj, src->obj, size); \
226  if (pad) \
227  memset(((uint8_t *) dest->obj) + size, 0, pad); \
228  }
229  alloc_and_copy_or_fail(extradata, src->extradata_size,
231  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
232  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
233  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
234  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
236 #undef alloc_and_copy_or_fail
237 
238  return 0;
239 
240 fail:
241  av_freep(&dest->rc_override);
242  av_freep(&dest->intra_matrix);
243  av_freep(&dest->inter_matrix);
244  av_freep(&dest->extradata);
245 #if FF_API_MPV_OPT
247  av_freep(&dest->rc_eq);
249 #endif
250  return AVERROR(ENOMEM);
251 }
252 
254 {
255  return &av_codec_context_class;
256 }
257 
258 #define FOFFSET(x) offsetof(AVFrame,x)
259 
260 static const AVOption frame_options[]={
261 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
262 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
263 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
264 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
265 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
266 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
267 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
268 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
269 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
270 {NULL},
271 };
272 
273 static const AVClass av_frame_class = {
274  .class_name = "AVFrame",
275  .item_name = NULL,
276  .option = frame_options,
277  .version = LIBAVUTIL_VERSION_INT,
278 };
279 
281 {
282  return &av_frame_class;
283 }
284 
285 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
286 
288 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
289 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
290 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
291 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
292 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
293 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
294 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
295 {NULL},
296 };
297 
299  .class_name = "AVSubtitleRect",
300  .item_name = NULL,
301  .option = subtitle_rect_options,
302  .version = LIBAVUTIL_VERSION_INT,
303 };
304 
306 {
307  return &av_subtitle_rect_class;
308 }