FFmpeg
codec_par.c
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1 /*
2  * AVCodecParameters functions for libavcodec
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * AVCodecParameters functions for libavcodec.
24  */
25 
26 #include <string.h>
27 #include "libavutil/mem.h"
28 #include "avcodec.h"
29 #include "codec_par.h"
30 #include "packet.h"
31 
32 static void codec_parameters_reset(AVCodecParameters *par)
33 {
34  av_freep(&par->extradata);
35  av_channel_layout_uninit(&par->ch_layout);
36  av_packet_side_data_free(&par->coded_side_data, &par->nb_coded_side_data);
37 
38  memset(par, 0, sizeof(*par));
39 
40  par->codec_type = AVMEDIA_TYPE_UNKNOWN;
41  par->codec_id = AV_CODEC_ID_NONE;
42  par->format = -1;
43  par->ch_layout.order = AV_CHANNEL_ORDER_UNSPEC;
44  par->field_order = AV_FIELD_UNKNOWN;
45  par->color_range = AVCOL_RANGE_UNSPECIFIED;
46  par->color_primaries = AVCOL_PRI_UNSPECIFIED;
47  par->color_trc = AVCOL_TRC_UNSPECIFIED;
48  par->color_space = AVCOL_SPC_UNSPECIFIED;
49  par->chroma_location = AVCHROMA_LOC_UNSPECIFIED;
50  par->sample_aspect_ratio = (AVRational){ 0, 1 };
51  par->framerate = (AVRational){ 0, 1 };
52  par->profile = AV_PROFILE_UNKNOWN;
53  par->level = AV_LEVEL_UNKNOWN;
54 }
55 
56 AVCodecParameters *avcodec_parameters_alloc(void)
57 {
58  AVCodecParameters *par = av_mallocz(sizeof(*par));
59 
60  if (!par)
61  return NULL;
62  codec_parameters_reset(par);
63  return par;
64 }
65 
66 void avcodec_parameters_free(AVCodecParameters **ppar)
67 {
68  AVCodecParameters *par = *ppar;
69 
70  if (!par)
71  return;
72  codec_parameters_reset(par);
73 
74  av_freep(ppar);
75 }
76 
77 static int codec_parameters_copy_side_data(AVPacketSideData **pdst, int *pnb_dst,
78  const AVPacketSideData *src, int nb_src)
79 {
80  AVPacketSideData *dst;
81  int nb_dst = *pnb_dst;
82 
83  if (!src)
84  return 0;
85 
86  *pdst = dst = av_calloc(nb_src, sizeof(*dst));
87  if (!dst)
88  return AVERROR(ENOMEM);
89 
90  for (int i = 0; i < nb_src; i++) {
91  const AVPacketSideData *src_sd = &src[i];
92  AVPacketSideData *dst_sd = &dst[i];
93 
94  dst_sd->data = av_memdup(src_sd->data, src_sd->size);
95  if (!dst_sd->data)
96  return AVERROR(ENOMEM);
97 
98  dst_sd->type = src_sd->type;
99  dst_sd->size = src_sd->size;
100  *pnb_dst = ++nb_dst;
101  }
102 
103  return 0;
104 }
105 
106 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
107 {
108  int ret;
109 
110  codec_parameters_reset(dst);
111  memcpy(dst, src, sizeof(*dst));
112 
113  dst->ch_layout = (AVChannelLayout){0};
114  dst->extradata = NULL;
115  dst->extradata_size = 0;
116  dst->coded_side_data = NULL;
117  dst->nb_coded_side_data = 0;
118  if (src->extradata) {
119  dst->extradata = av_mallocz(src->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
120  if (!dst->extradata)
121  return AVERROR(ENOMEM);
122  memcpy(dst->extradata, src->extradata, src->extradata_size);
123  dst->extradata_size = src->extradata_size;
124  }
125  ret = codec_parameters_copy_side_data(&dst->coded_side_data, &dst->nb_coded_side_data,
126  src->coded_side_data, src->nb_coded_side_data);
127  if (ret < 0)
128  return ret;
129 
130  ret = av_channel_layout_copy(&dst->ch_layout, &src->ch_layout);
131  if (ret < 0)
132  return ret;
133 
134  return 0;
135 }
136 
137 int avcodec_parameters_from_context(AVCodecParameters *par,
138  const AVCodecContext *codec)
139 {
140  int ret;
141 
142  codec_parameters_reset(par);
143 
144  par->codec_type = codec->codec_type;
145  par->codec_id = codec->codec_id;
146  par->codec_tag = codec->codec_tag;
147 
148  par->bit_rate = codec->bit_rate;
149  par->bits_per_coded_sample = codec->bits_per_coded_sample;
150  par->bits_per_raw_sample = codec->bits_per_raw_sample;
151  par->profile = codec->profile;
152  par->level = codec->level;
153 
154  switch (par->codec_type) {
155  case AVMEDIA_TYPE_VIDEO:
156  par->format = codec->pix_fmt;
157  par->width = codec->width;
158  par->height = codec->height;
159  par->field_order = codec->field_order;
160  par->color_range = codec->color_range;
161  par->color_primaries = codec->color_primaries;
162  par->color_trc = codec->color_trc;
163  par->color_space = codec->colorspace;
164  par->chroma_location = codec->chroma_sample_location;
165  par->sample_aspect_ratio = codec->sample_aspect_ratio;
166  par->video_delay = codec->has_b_frames;
167  par->framerate = codec->framerate;
168  break;
169  case AVMEDIA_TYPE_AUDIO:
170  par->format = codec->sample_fmt;
171  ret = av_channel_layout_copy(&par->ch_layout, &codec->ch_layout);
172  if (ret < 0)
173  return ret;
174  par->sample_rate = codec->sample_rate;
175  par->block_align = codec->block_align;
176  par->frame_size = codec->frame_size;
177  par->initial_padding = codec->initial_padding;
178  par->trailing_padding = codec->trailing_padding;
179  par->seek_preroll = codec->seek_preroll;
180  break;
181  case AVMEDIA_TYPE_SUBTITLE:
182  par->width = codec->width;
183  par->height = codec->height;
184  break;
185  }
186 
187  if (codec->extradata) {
188  par->extradata = av_mallocz(codec->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
189  if (!par->extradata)
190  return AVERROR(ENOMEM);
191  memcpy(par->extradata, codec->extradata, codec->extradata_size);
192  par->extradata_size = codec->extradata_size;
193  }
194 
195  ret = codec_parameters_copy_side_data(&par->coded_side_data, &par->nb_coded_side_data,
196  codec->coded_side_data, codec->nb_coded_side_data);
197  if (ret < 0)
198  return ret;
199 
200  return 0;
201 }
202 
203 int avcodec_parameters_to_context(AVCodecContext *codec,
204  const AVCodecParameters *par)
205 {
206  int ret;
207 
208  codec->codec_type = par->codec_type;
209  codec->codec_id = par->codec_id;
210  codec->codec_tag = par->codec_tag;
211 
212  codec->bit_rate = par->bit_rate;
213  codec->bits_per_coded_sample = par->bits_per_coded_sample;
214  codec->bits_per_raw_sample = par->bits_per_raw_sample;
215  codec->profile = par->profile;
216  codec->level = par->level;
217 
218  switch (par->codec_type) {
219  case AVMEDIA_TYPE_VIDEO:
220  codec->pix_fmt = par->format;
221  codec->width = par->width;
222  codec->height = par->height;
223  codec->field_order = par->field_order;
224  codec->color_range = par->color_range;
225  codec->color_primaries = par->color_primaries;
226  codec->color_trc = par->color_trc;
227  codec->colorspace = par->color_space;
228  codec->chroma_sample_location = par->chroma_location;
229  codec->sample_aspect_ratio = par->sample_aspect_ratio;
230  codec->has_b_frames = par->video_delay;
231  codec->framerate = par->framerate;
232  break;
233  case AVMEDIA_TYPE_AUDIO:
234  codec->sample_fmt = par->format;
235  ret = av_channel_layout_copy(&codec->ch_layout, &par->ch_layout);
236  if (ret < 0)
237  return ret;
238  codec->sample_rate = par->sample_rate;
239  codec->block_align = par->block_align;
240  codec->frame_size = par->frame_size;
241  codec->delay =
242  codec->initial_padding = par->initial_padding;
243  codec->trailing_padding = par->trailing_padding;
244  codec->seek_preroll = par->seek_preroll;
245  break;
246  case AVMEDIA_TYPE_SUBTITLE:
247  codec->width = par->width;
248  codec->height = par->height;
249  break;
250  }
251 
252  av_freep(&codec->extradata);
253  codec->extradata_size = 0;
254  if (par->extradata) {
255  codec->extradata = av_mallocz(par->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
256  if (!codec->extradata)
257  return AVERROR(ENOMEM);
258  memcpy(codec->extradata, par->extradata, par->extradata_size);
259  codec->extradata_size = par->extradata_size;
260  }
261 
262  av_packet_side_data_free(&codec->coded_side_data, &codec->nb_coded_side_data);
263  ret = codec_parameters_copy_side_data(&codec->coded_side_data, &codec->nb_coded_side_data,
264  par->coded_side_data, par->nb_coded_side_data);
265  if (ret < 0)
266  return ret;
267 
268  return 0;
269 }
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:203
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
AVCodecParameters::color_space
enum AVColorSpace color_space
Definition: codec_par.h:169
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Definition: codec_par.c:203
AVPacketSideData
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition: packet.h:403
AVCodecParameters::seek_preroll
int seek_preroll
Audio only.
Definition: codec_par.h:214
AVCOL_TRC_UNSPECIFIED
@ AVCOL_TRC_UNSPECIFIED
Definition: pixfmt.h:664
AVCodecParameters::framerate
AVRational framerate
Video only.
Definition: codec_par.h:156
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:59
AVChannelLayout::order
enum AVChannelOrder order
Channel order used in this layout.
Definition: channel_layout.h:324
av_memdup
void * av_memdup(const void *p, size_t size)
Duplicate a buffer with av_malloc().
Definition: mem.c:304
AVCodecParameters::color_primaries
enum AVColorPrimaries color_primaries
Definition: codec_par.h:167
AVPacketSideData::size
size_t size
Definition: packet.h:405
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:440
AVCodecParameters::bits_per_raw_sample
int bits_per_raw_sample
This is the number of valid bits in each output sample.
Definition: codec_par.h:123
AVCodecParameters::color_trc
enum AVColorTransferCharacteristic color_trc
Definition: codec_par.h:168
AV_PROFILE_UNKNOWN
#define AV_PROFILE_UNKNOWN
Definition: defs.h:65
AV_FIELD_UNKNOWN
@ AV_FIELD_UNKNOWN
Definition: defs.h:212
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:195
AVCodecParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only.
Definition: codec_par.h:144
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:201
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
AV_CHANNEL_ORDER_UNSPEC
@ AV_CHANNEL_ORDER_UNSPEC
Only the channel count is specified, without any further information about the channel order.
Definition: channel_layout.h:119
AVPacketSideData::data
uint8_t * data
Definition: packet.h:404
AVCodecParameters::nb_coded_side_data
int nb_coded_side_data
Amount of entries in coded_side_data.
Definition: codec_par.h:86
AVCOL_PRI_UNSPECIFIED
@ AVCOL_PRI_UNSPECIFIED
Definition: pixfmt.h:639
av_packet_side_data_free
void av_packet_side_data_free(AVPacketSideData **psd, int *pnb_sd)
Convenience function to free all the side data stored in an array, and the array itself.
Definition: packet.c:747
NULL
#define NULL
Definition: coverity.c:32
avcodec_parameters_free
void avcodec_parameters_free(AVCodecParameters **ppar)
Free an AVCodecParameters instance and everything associated with it and write NULL to the supplied p...
Definition: codec_par.c:66
AV_LEVEL_UNKNOWN
#define AV_LEVEL_UNKNOWN
Definition: defs.h:209
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVPacketSideData::type
enum AVPacketSideDataType type
Definition: packet.h:406
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCOL_RANGE_UNSPECIFIED
@ AVCOL_RANGE_UNSPECIFIED
Definition: pixfmt.h:733
AVCodecParameters::level
int level
Definition: codec_par.h:129
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:319
dst
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
Definition: dsp.h:87
AVCodecParameters::profile
int profile
Codec-specific bitstream restrictions that the stream conforms to.
Definition: codec_par.h:128
AVCHROMA_LOC_UNSPECIFIED
@ AVCHROMA_LOC_UNSPECIFIED
Definition: pixfmt.h:787
AVMEDIA_TYPE_UNKNOWN
@ AVMEDIA_TYPE_UNKNOWN
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:199
codec_parameters_reset
static void codec_parameters_reset(AVCodecParameters *par)
Definition: codec_par.c:32
avcodec_parameters_alloc
AVCodecParameters * avcodec_parameters_alloc(void)
Allocate a new AVCodecParameters and set its fields to default values (unknown/invalid/0).
Definition: codec_par.c:56
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
codec_parameters_copy_side_data
static int codec_parameters_copy_side_data(AVPacketSideData **pdst, int *pnb_dst, const AVPacketSideData *src, int nb_src)
Definition: codec_par.c:77
packet.h
AVCodecParameters::height
int height
Definition: codec_par.h:135
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:256
AVCodecParameters::color_range
enum AVColorRange color_range
Video only.
Definition: codec_par.h:166
AVCOL_SPC_UNSPECIFIED
@ AVCOL_SPC_UNSPECIFIED
Definition: pixfmt.h:693
AVCodecParameters::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire stream.
Definition: codec_par.h:81
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:264
AVCodecParameters::field_order
enum AVFieldOrder field_order
Video only.
Definition: codec_par.h:161
avcodec.h
ret
ret
Definition: filter_design.txt:187
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
AVCodecParameters::chroma_location
enum AVChromaLocation chroma_location
Definition: codec_par.h:170
AVCodecParameters::trailing_padding
int trailing_padding
Audio only.
Definition: codec_par.h:210
AVCodecContext
main external API structure.
Definition: avcodec.h:431
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:442
av_channel_layout_copy
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
Make a copy of a channel layout.
Definition: channel_layout.c:449
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:200
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
mem.h
AVCodecParameters::video_delay
int video_delay
Video only.
Definition: codec_par.h:175
avcodec_parameters_from_context
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:137
AVCodecParameters::format
int format
Definition: codec_par.h:92
codec_par.h
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:203
src
#define src
Definition: vp8dsp.c:248
avcodec_parameters_copy
int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
Copy the contents of src to dst.
Definition: codec_par.c:106
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