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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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 
71  .class_name = "AVCodecContext",
72  .item_name = context_to_name,
73  .option = options,
74  .version = LIBAVUTIL_VERSION_INT,
75  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
76  .child_next = codec_child_next,
77  .child_class_next = codec_child_class_next,
78 };
79 
81 {
82  memset(s, 0, sizeof(AVCodecContext));
83 
85 
86  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
87  s->codec = codec;
89 
90  s->time_base = (AVRational){0,1};
96  s->sample_aspect_ratio = (AVRational){0,1};
99 
102  if(codec && codec->priv_data_size){
103  if(!s->priv_data){
104  s->priv_data= av_mallocz(codec->priv_data_size);
105  if (!s->priv_data) {
106  return AVERROR(ENOMEM);
107  }
108  }
109  if(codec->priv_class){
110  *(const AVClass**)s->priv_data = codec->priv_class;
112  }
113  }
114  if (codec && codec->defaults) {
115  int ret;
116  const AVCodecDefault *d = codec->defaults;
117  while (d->key) {
118  ret = av_opt_set(s, d->key, d->value, 0);
119  av_assert0(ret >= 0);
120  d++;
121  }
122  }
123  return 0;
124 }
125 
127 {
128  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
129 
130  if(avctx==NULL) return NULL;
131 
132  if(avcodec_get_context_defaults3(avctx, codec) < 0){
133  av_free(avctx);
134  return NULL;
135  }
136 
137  return avctx;
138 }
139 
141 {
142  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
143  av_log(dest, AV_LOG_ERROR,
144  "Tried to copy AVCodecContext %p into already-initialized %p\n",
145  src, dest);
146  return AVERROR(EINVAL);
147  }
148  memcpy(dest, src, sizeof(*dest));
149 
150  /* set values specific to opened codecs back to their default state */
151  dest->priv_data = NULL;
152  dest->codec = NULL;
153  dest->slice_offset = NULL;
154  dest->hwaccel = NULL;
155  dest->thread_opaque = NULL;
156  dest->internal = NULL;
157 
158  /* reallocate values that should be allocated separately */
159  dest->rc_eq = NULL;
160  dest->extradata = NULL;
161  dest->intra_matrix = NULL;
162  dest->inter_matrix = NULL;
163  dest->rc_override = NULL;
164  if (src->rc_eq) {
165  dest->rc_eq = av_strdup(src->rc_eq);
166  if (!dest->rc_eq)
167  return AVERROR(ENOMEM);
168  }
169 
170 #define alloc_and_copy_or_fail(obj, size, pad) \
171  if (src->obj && size > 0) { \
172  dest->obj = av_malloc(size + pad); \
173  if (!dest->obj) \
174  goto fail; \
175  memcpy(dest->obj, src->obj, size); \
176  if (pad) \
177  memset(((uint8_t *) dest->obj) + size, 0, pad); \
178  }
179  alloc_and_copy_or_fail(extradata, src->extradata_size,
181  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
182  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
183  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
184 #undef alloc_and_copy_or_fail
185 
186  return 0;
187 
188 fail:
189  av_freep(&dest->rc_override);
190  av_freep(&dest->intra_matrix);
191  av_freep(&dest->inter_matrix);
192  av_freep(&dest->extradata);
193  av_freep(&dest->rc_eq);
194  return AVERROR(ENOMEM);
195 }
196 
198 {
199  return &av_codec_context_class;
200 }