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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/mem.h"
31 #include "libavutil/opt.h"
32 #include <float.h> /* FLT_MIN, FLT_MAX */
33 #include <string.h>
34 
35 #include "options_table.h"
36 
37 static const char* context_to_name(void* ptr) {
38  AVCodecContext *avc= ptr;
39 
40  if(avc && avc->codec && avc->codec->name)
41  return avc->codec->name;
42  else
43  return "NULL";
44 }
45 
46 static void *codec_child_next(void *obj, void *prev)
47 {
48  AVCodecContext *s = obj;
49  if (!prev && s->codec && s->codec->priv_class && s->priv_data)
50  return s->priv_data;
51  return NULL;
52 }
53 
54 static const AVClass *codec_child_class_next(const AVClass *prev)
55 {
56  AVCodec *c = NULL;
57 
58  /* find the codec that corresponds to prev */
59  while (prev && (c = av_codec_next(c)))
60  if (c->priv_class == prev)
61  break;
62 
63  /* find next codec with priv options */
64  while (c = av_codec_next(c))
65  if (c->priv_class)
66  return c->priv_class;
67  return NULL;
68 }
69 
70 static AVClassCategory get_category(void *ptr)
71 {
72  AVCodecContext* avctx = ptr;
73  if(avctx->codec && avctx->codec->decode) return AV_CLASS_CATEGORY_DECODER;
74  else return AV_CLASS_CATEGORY_ENCODER;
75 }
76 
78  .class_name = "AVCodecContext",
79  .item_name = context_to_name,
80  .option = avcodec_options,
81  .version = LIBAVUTIL_VERSION_INT,
82  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
83  .child_next = codec_child_next,
84  .child_class_next = codec_child_class_next,
86  .get_category = get_category,
87 };
88 
90 {
91  int flags=0;
92  memset(s, 0, sizeof(AVCodecContext));
93 
95 
96  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
97  if (codec)
98  s->codec_id = codec->id;
99 
102  else if(s->codec_type == AVMEDIA_TYPE_VIDEO)
104  else if(s->codec_type == AVMEDIA_TYPE_SUBTITLE)
106  av_opt_set_defaults2(s, flags, flags);
107 
108  s->time_base = (AVRational){0,1};
113  s->sample_aspect_ratio = (AVRational){0,1};
116  s->timecode_frame_start = -1;
117 
119  if(codec && codec->priv_data_size){
120  if(!s->priv_data){
121  s->priv_data= av_mallocz(codec->priv_data_size);
122  if (!s->priv_data) {
123  return AVERROR(ENOMEM);
124  }
125  }
126  if(codec->priv_class){
127  *(const AVClass**)s->priv_data = codec->priv_class;
129  }
130  }
131  if (codec && codec->defaults) {
132  int ret;
133  const AVCodecDefault *d = codec->defaults;
134  while (d->key) {
135  ret = av_opt_set(s, d->key, d->value, 0);
136  av_assert0(ret >= 0);
137  d++;
138  }
139  }
140  return 0;
141 }
142 
144 {
145  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
146 
147  if(avctx==NULL) return NULL;
148 
149  if(avcodec_get_context_defaults3(avctx, codec) < 0){
150  av_free(avctx);
151  return NULL;
152  }
153 
154  return avctx;
155 }
156 
158 {
159  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
160  av_log(dest, AV_LOG_ERROR,
161  "Tried to copy AVCodecContext %p into already-initialized %p\n",
162  src, dest);
163  return AVERROR(EINVAL);
164  }
165 
166  av_opt_free(dest);
167  av_free(dest->priv_data);
168 
169  memcpy(dest, src, sizeof(*dest));
170 
171  /* set values specific to opened codecs back to their default state */
172  dest->priv_data = NULL;
173  dest->codec = NULL;
174  dest->slice_offset = NULL;
175  dest->hwaccel = NULL;
176  dest->internal = NULL;
177 
178  /* reallocate values that should be allocated separately */
179  dest->rc_eq = NULL;
180  dest->extradata = NULL;
181  dest->intra_matrix = NULL;
182  dest->inter_matrix = NULL;
183  dest->rc_override = NULL;
184  if (src->rc_eq) {
185  dest->rc_eq = av_strdup(src->rc_eq);
186  if (!dest->rc_eq)
187  return AVERROR(ENOMEM);
188  }
189 
190 #define alloc_and_copy_or_fail(obj, size, pad) \
191  if (src->obj && size > 0) { \
192  dest->obj = av_malloc(size + pad); \
193  if (!dest->obj) \
194  goto fail; \
195  memcpy(dest->obj, src->obj, size); \
196  if (pad) \
197  memset(((uint8_t *) dest->obj) + size, 0, pad); \
198  }
199  alloc_and_copy_or_fail(extradata, src->extradata_size,
201  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
202  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
203  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
204  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 1);
205 #undef alloc_and_copy_or_fail
206 
207  return 0;
208 
209 fail:
210  av_freep(&dest->rc_override);
211  av_freep(&dest->intra_matrix);
212  av_freep(&dest->inter_matrix);
213  av_freep(&dest->extradata);
214  av_freep(&dest->rc_eq);
215  return AVERROR(ENOMEM);
216 }
217 
219 {
220  return &av_codec_context_class;
221 }
222 
223 #define FOFFSET(x) offsetof(AVFrame,x)
224 
225 static const AVOption frame_options[]={
226 {"best_effort_timestamp", "", FOFFSET(best_effort_timestamp), AV_OPT_TYPE_INT64, {.i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, 0},
227 {"pkt_pos", "", FOFFSET(pkt_pos), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
228 {"pkt_size", "", FOFFSET(pkt_size), AV_OPT_TYPE_INT64, {.i64 = -1 }, INT64_MIN, INT64_MAX, 0},
229 {"sample_aspect_ratio", "", FOFFSET(sample_aspect_ratio), AV_OPT_TYPE_RATIONAL, {.dbl = 0 }, 0, INT_MAX, 0},
230 {"width", "", FOFFSET(width), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
231 {"height", "", FOFFSET(height), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
232 {"format", "", FOFFSET(format), AV_OPT_TYPE_INT, {.i64 = -1 }, 0, INT_MAX, 0},
233 {"channel_layout", "", FOFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, 0},
234 {"sample_rate", "", FOFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
235 {NULL},
236 };
237 
238 static const AVClass av_frame_class = {
239  .class_name = "AVFrame",
240  .item_name = NULL,
241  .option = frame_options,
242  .version = LIBAVUTIL_VERSION_INT,
243 };
244 
246 {
247  return &av_frame_class;
248 }
249 
250 #define SROFFSET(x) offsetof(AVSubtitleRect,x)
251 
253 {"x", "", SROFFSET(x), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
254 {"y", "", SROFFSET(y), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
255 {"w", "", SROFFSET(w), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
256 {"h", "", SROFFSET(h), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
257 {"type", "", SROFFSET(type), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, 0},
258 {"flags", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0, "flags"},
259 {"forced", "", SROFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, 1, 0},
260 {NULL},
261 };
262 
264  .class_name = "AVSubtitleRect",
265  .item_name = NULL,
266  .option = subtitle_rect_options,
267  .version = LIBAVUTIL_VERSION_INT,
268 };
269 
271 {
272  return &av_subtitle_rect_class;
273 }