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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 = codec;
100  s->codec_id = codec->id;
101  }
102 
105  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
107  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
109  av_opt_set_defaults2(s, flags, flags);
110 
111  s->time_base = (AVRational){0,1};
112  s->framerate = (AVRational){ 0, 1 };
113  s->pkt_timebase = (AVRational){ 0, 1 };
118  s->sample_aspect_ratio = (AVRational){0,1};
121 
123  if(codec && codec->priv_data_size){
124  if(!s->priv_data){
125  s->priv_data= av_mallocz(codec->priv_data_size);
126  if (!s->priv_data) {
127  return AVERROR(ENOMEM);
128  }
129  }
130  if(codec->priv_class){
131  *(const AVClass**)s->priv_data = codec->priv_class;
133  }
134  }
135  if (codec && codec->defaults) {
136  int ret;
137  const AVCodecDefault *d = codec->defaults;
138  while (d->key) {
139  ret = av_opt_set(s, d->key, d->value, 0);
140  av_assert0(ret >= 0);
141  d++;
142  }
143  }
144  return 0;
145 }
146 
148 {
149  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
150 
151  if (!avctx)
152  return NULL;
153 
154  if(avcodec_get_context_defaults3(avctx, codec) < 0){
155  av_free(avctx);
156  return NULL;
157  }
158 
159  return avctx;
160 }
161 
163 {
164  AVCodecContext *avctx = *pavctx;
165 
166  if (!avctx)
167  return;
168 
169  avcodec_close(avctx);
170 
171  av_freep(&avctx->extradata);
172  av_freep(&avctx->subtitle_header);
173 
174  av_freep(pavctx);
175 }
176 
178 {
179  const AVCodec *orig_codec = dest->codec;
180  uint8_t *orig_priv_data = dest->priv_data;
181 
182  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
183  av_log(dest, AV_LOG_ERROR,
184  "Tried to copy AVCodecContext %p into already-initialized %p\n",
185  src, dest);
186  return AVERROR(EINVAL);
187  }
188 
189  av_opt_free(dest);
190 
191  memcpy(dest, src, sizeof(*dest));
192  av_opt_copy(dest, src);
193 
194  dest->priv_data = orig_priv_data;
195 
196  if (orig_priv_data)
197  av_opt_copy(orig_priv_data, src->priv_data);
198 
199  dest->codec = orig_codec;
200 
201  /* set values specific to opened codecs back to their default state */
202  dest->slice_offset = NULL;
203  dest->hwaccel = NULL;
204  dest->internal = NULL;
205 
206  /* reallocate values that should be allocated separately */
207  dest->extradata = NULL;
208  dest->intra_matrix = NULL;
209  dest->inter_matrix = NULL;
210  dest->rc_override = NULL;
211  dest->subtitle_header = NULL;
212 #if FF_API_MPV_OPT
214  dest->rc_eq = NULL;
215  if (src->rc_eq) {
216  dest->rc_eq = av_strdup(src->rc_eq);
217  if (!dest->rc_eq)
218  return AVERROR(ENOMEM);
219  }
221 #endif
222 
223 #define alloc_and_copy_or_fail(obj, size, pad) \
224  if (src->obj && size > 0) { \
225  dest->obj = av_malloc(size + pad); \
226  if (!dest->obj) \
227  goto fail; \
228  memcpy(dest->obj, src->obj, size); \
229  if (pad) \
230  memset(((uint8_t *) dest->obj) + size, 0, pad); \
231  }
232  alloc_and_copy_or_fail(extradata, src->extradata_size,
234  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
235  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
236  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
237  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
239 #undef alloc_and_copy_or_fail
240 
241  return 0;
242 
243 fail:
244  av_freep(&dest->rc_override);
245  av_freep(&dest->intra_matrix);
246  av_freep(&dest->inter_matrix);
247  av_freep(&dest->extradata);
248 #if FF_API_MPV_OPT
250  av_freep(&dest->rc_eq);
252 #endif
253  return AVERROR(ENOMEM);
254 }
255 
257 {
258  return &av_codec_context_class;
259 }
260 
261 #define FOFFSET(x) offsetof(AVFrame,x)
262 
263 static const AVOption frame_options[]={
264 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
265 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
266 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
267 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
268 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
269 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
270 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
271 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
272 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
273 {NULL},
274 };
275 
276 static const AVClass av_frame_class = {
277  .class_name = "AVFrame",
278  .item_name = NULL,
279  .option = frame_options,
280  .version = LIBAVUTIL_VERSION_INT,
281 };
282 
284 {
285  return &av_frame_class;
286 }
287 
288 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
289 
291 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
292 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
293 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
294 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
295 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
296 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
297 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
298 {NULL},
299 };
300 
302  .class_name = "AVSubtitleRect",
303  .item_name = NULL,
304  .option = subtitle_rect_options,
305  .version = LIBAVUTIL_VERSION_INT,
306 };
307 
309 {
310  return &av_subtitle_rect_class;
311 }