Libav
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/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 
37 #include "options_table.h"
39 
40 static const char* context_to_name(void* ptr) {
41  AVCodecContext *avc= ptr;
42 
43  if(avc && avc->codec && avc->codec->name)
44  return avc->codec->name;
45  else
46  return "NULL";
47 }
48 
49 static void *codec_child_next(void *obj, void *prev)
50 {
51  AVCodecContext *s = obj;
52  if (!prev && s->codec && s->codec->priv_class && s->priv_data)
53  return s->priv_data;
54  return NULL;
55 }
56 
57 static const AVClass *codec_child_class_next(const AVClass *prev)
58 {
59  AVCodec *c = NULL;
60 
61  /* find the codec that corresponds to prev */
62  while (prev && (c = av_codec_next(c)))
63  if (c->priv_class == prev)
64  break;
65 
66  /* find next codec with priv options */
67  while (c = av_codec_next(c))
68  if (c->priv_class)
69  return c->priv_class;
70  return NULL;
71 }
72 
74  .class_name = "AVCodecContext",
75  .item_name = context_to_name,
76  .option = avcodec_options,
77  .version = LIBAVUTIL_VERSION_INT,
78  .log_level_offset_offset = offsetof(AVCodecContext, log_level_offset),
79  .child_next = codec_child_next,
80  .child_class_next = codec_child_class_next,
81 };
82 
83 static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
84 {
85  memset(s, 0, sizeof(AVCodecContext));
86 
88 
89  s->codec_type = codec ? codec->type : AVMEDIA_TYPE_UNKNOWN;
90  s->codec = codec;
92 
93  s->time_base = (AVRational){0,1};
94  s->framerate = (AVRational){ 0, 1 };
99  s->sample_aspect_ratio = (AVRational){0,1};
103 
105  if(codec && codec->priv_data_size){
106  if(!s->priv_data){
107  s->priv_data= av_mallocz(codec->priv_data_size);
108  if (!s->priv_data) {
109  return AVERROR(ENOMEM);
110  }
111  }
112  if(codec->priv_class){
113  *(const AVClass**)s->priv_data = codec->priv_class;
115  }
116  }
117  if (codec && codec->defaults) {
118  int ret;
119  const AVCodecDefault *d = codec->defaults;
120  while (d->key) {
121  ret = av_opt_set(s, d->key, d->value, 0);
122  av_assert0(ret >= 0);
123  d++;
124  }
125  }
126  return 0;
127 }
128 
129 #if FF_API_GET_CONTEXT_DEFAULTS
131 {
132  return init_context_defaults(s, codec);
133 }
134 #endif
135 
137 {
138  AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
139 
140  if (!avctx)
141  return NULL;
142 
143  if (init_context_defaults(avctx, codec) < 0) {
144  av_free(avctx);
145  return NULL;
146  }
147 
148  return avctx;
149 }
150 
152 {
153  AVCodecContext *avctx = *pavctx;
154 
155  if (!avctx)
156  return;
157 
158  avcodec_close(avctx);
159 
160  av_freep(&avctx->extradata);
161  av_freep(&avctx->subtitle_header);
162 
163  av_freep(pavctx);
164 }
165 
166 #if FF_API_COPY_CONTEXT
168 {
169  const AVCodec *orig_codec = dest->codec;
170  uint8_t *orig_priv_data = dest->priv_data;
171 
172  if (avcodec_is_open(dest)) { // check that the dest context is uninitialized
173  av_log(dest, AV_LOG_ERROR,
174  "Tried to copy AVCodecContext %p into already-initialized %p\n",
175  src, dest);
176  return AVERROR(EINVAL);
177  }
178  memcpy(dest, src, sizeof(*dest));
179 
180  dest->priv_data = orig_priv_data;
181  dest->codec = orig_codec;
182 
183  /* set values specific to opened codecs back to their default state */
184  dest->slice_offset = NULL;
185  dest->hwaccel = NULL;
186  dest->internal = NULL;
187 
188  /* reallocate values that should be allocated separately */
189  dest->extradata = NULL;
190  dest->intra_matrix = NULL;
191  dest->inter_matrix = NULL;
192  dest->rc_override = NULL;
193  dest->subtitle_header = NULL;
194  dest->hw_frames_ctx = NULL;
195 #if FF_API_MPV_OPT
197  dest->rc_eq = NULL;
198  if (src->rc_eq) {
199  dest->rc_eq = av_strdup(src->rc_eq);
200  if (!dest->rc_eq)
201  return AVERROR(ENOMEM);
202  }
204 #endif
205 
206 #define alloc_and_copy_or_fail(obj, size, pad) \
207  if (src->obj && size > 0) { \
208  dest->obj = av_malloc(size + pad); \
209  if (!dest->obj) \
210  goto fail; \
211  memcpy(dest->obj, src->obj, size); \
212  if (pad) \
213  memset(((uint8_t *) dest->obj) + size, 0, pad); \
214  }
215  alloc_and_copy_or_fail(extradata, src->extradata_size,
217  alloc_and_copy_or_fail(intra_matrix, 64 * sizeof(int16_t), 0);
218  alloc_and_copy_or_fail(inter_matrix, 64 * sizeof(int16_t), 0);
219  alloc_and_copy_or_fail(rc_override, src->rc_override_count * sizeof(*src->rc_override), 0);
220  alloc_and_copy_or_fail(subtitle_header, src->subtitle_header_size, 0);
222 #undef alloc_and_copy_or_fail
223 
224  if (src->hw_frames_ctx) {
226  if (!dest->hw_frames_ctx)
227  goto fail;
228  }
229 
230  return 0;
231 
232 fail:
233  av_freep(&dest->subtitle_header);
234  av_freep(&dest->rc_override);
235  av_freep(&dest->intra_matrix);
236  av_freep(&dest->inter_matrix);
237  av_freep(&dest->extradata);
239 #if FF_API_MPV_OPT
241  av_freep(&dest->rc_eq);
243 #endif
244  return AVERROR(ENOMEM);
245 }
246 #endif
247 
249 {
250  return &av_codec_context_class;
251 }
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:1671
const struct AVCodec * codec
Definition: avcodec.h:1418
AVRational framerate
Definition: avcodec.h:3063
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
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:106
int avcodec_default_execute2(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int, int), void *arg, int *ret, int count)
memory handling functions
void av_opt_set_defaults(void *s)
Set the values of all AVOption fields to their default values.
Definition: opt.c:599
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel...
Definition: avcodec.h:1804
static const AVOption avcodec_options[]
Definition: options_table.h:42
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
enum AVMediaType type
Definition: avcodec.h:3133
AVCodec.
Definition: avcodec.h:3120
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1535
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:202
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:248
static const AVClass av_codec_context_class
Definition: options.c:73
struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:2696
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:39
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static int init_context_defaults(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:83
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: utils.c:733
attribute_deprecated const char * rc_eq
Definition: avcodec.h:2379
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2160
uint8_t
AVOptions.
int subtitle_header_size
Definition: avcodec.h:3000
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1523
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:1414
#define src
Definition: vp8dsp.c:254
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: utils.c:1943
const AVCodecDefault * defaults
Private codec-specific defaults.
Definition: avcodec.h:3183
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:190
#define AVERROR(e)
Definition: error.h:43
AVCodec * av_codec_next(const AVCodec *c)
If c is NULL, returns the first registered codec, if c is non-NULL, returns the next registered codec...
Definition: utils.c:76
int avcodec_is_open(AVCodecContext *s)
Definition: utils.c:2702
static void * codec_child_next(void *obj, void *prev)
Definition: options.c:49
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
#define fail()
Definition: checkasm.h:80
common internal API header
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:2371
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
Copy the settings of the source AVCodecContext into the destination AVCodecContext.
Definition: options.c:167
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:136
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:3102
int priv_data_size
Definition: avcodec.h:3158
static const AVClass * codec_child_class_next(const AVClass *prev)
Definition: options.c:57
int64_t reordered_opaque
opaque 64-bit number (generally a PTS) that will be reordered and output in AVFrame.reordered_opaque
Definition: avcodec.h:2689
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:193
LIBAVUTIL_VERSION_INT
Definition: eval.c:55
RcOverride * rc_override
Definition: avcodec.h:2372
int(* execute2)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count)
The codec may call this to execute several independent things.
Definition: avcodec.h:2866
NULL
Definition: eval.c:55
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: utils.c:514
Libavcodec external API header.
enum AVMediaType codec_type
Definition: avcodec.h:1417
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:151
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:219
main external API structure.
Definition: avcodec.h:1409
int extradata_size
Definition: avcodec.h:1524
uint16_t * intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1963
Describe the class of an AVClass context structure.
Definition: log.h:34
int(* get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags)
This callback is called at the beginning of each frame to get data buffer(s) for it.
Definition: avcodec.h:2304
rational number numerator/denominator
Definition: rational.h:43
uint16_t * inter_matrix
custom inter quantization matrix
Definition: avcodec.h:1970
const AVClass * priv_class
AVClass for the private context.
Definition: avcodec.h:3148
const uint8_t * key
Definition: internal.h:159
const uint8_t * value
Definition: internal.h:160
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:77
common internal api header.
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:92
int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec)
Definition: options.c:130
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:638
void * priv_data
Definition: avcodec.h:1451
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:78
#define alloc_and_copy_or_fail(obj, size, pad)
struct AVCodecInternal * internal
Private context used for internal data.
Definition: avcodec.h:1459
FF_DISABLE_DEPRECATION_WARNINGS static FF_ENABLE_DEPRECATION_WARNINGS const char * context_to_name(void *ptr)
Definition: options.c:40
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:1795
int(* execute)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size)
The codec may call this to execute several independent things.
Definition: avcodec.h:2846
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:247
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:211
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:3070
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:235
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: utils.c:703
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:2999