FFmpeg
codec_par.h
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1 /*
2  * Codec parameters public API
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 #ifndef AVCODEC_CODEC_PAR_H
22 #define AVCODEC_CODEC_PAR_H
23 
24 #include <stdint.h>
25 
26 #include "libavutil/avutil.h"
28 #include "libavutil/rational.h"
29 #include "libavutil/pixfmt.h"
30 
31 #include "codec_id.h"
32 
33 /**
34  * @addtogroup lavc_core
35  * @{
36  */
37 
41  AV_FIELD_TT, ///< Top coded_first, top displayed first
42  AV_FIELD_BB, ///< Bottom coded first, bottom displayed first
43  AV_FIELD_TB, ///< Top coded first, bottom displayed first
44  AV_FIELD_BT, ///< Bottom coded first, top displayed first
45 };
46 
47 /**
48  * This struct describes the properties of an encoded stream.
49  *
50  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
51  * be allocated with avcodec_parameters_alloc() and freed with
52  * avcodec_parameters_free().
53  */
54 typedef struct AVCodecParameters {
55  /**
56  * General type of the encoded data.
57  */
59  /**
60  * Specific type of the encoded data (the codec used).
61  */
63  /**
64  * Additional information about the codec (corresponds to the AVI FOURCC).
65  */
66  uint32_t codec_tag;
67 
68  /**
69  * Extra binary data needed for initializing the decoder, codec-dependent.
70  *
71  * Must be allocated with av_malloc() and will be freed by
72  * avcodec_parameters_free(). The allocated size of extradata must be at
73  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
74  * bytes zeroed.
75  */
76  uint8_t *extradata;
77  /**
78  * Size of the extradata content in bytes.
79  */
81 
82  /**
83  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
84  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
85  */
86  int format;
87 
88  /**
89  * The average bitrate of the encoded data (in bits per second).
90  */
91  int64_t bit_rate;
92 
93  /**
94  * The number of bits per sample in the codedwords.
95  *
96  * This is basically the bitrate per sample. It is mandatory for a bunch of
97  * formats to actually decode them. It's the number of bits for one sample in
98  * the actual coded bitstream.
99  *
100  * This could be for example 4 for ADPCM
101  * For PCM formats this matches bits_per_raw_sample
102  * Can be 0
103  */
105 
106  /**
107  * This is the number of valid bits in each output sample. If the
108  * sample format has more bits, the least significant bits are additional
109  * padding bits, which are always 0. Use right shifts to reduce the sample
110  * to its actual size. For example, audio formats with 24 bit samples will
111  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
112  * To get the original sample use "(int32_t)sample >> 8"."
113  *
114  * For ADPCM this might be 12 or 16 or similar
115  * Can be 0
116  */
118 
119  /**
120  * Codec-specific bitstream restrictions that the stream conforms to.
121  */
122  int profile;
123  int level;
124 
125  /**
126  * Video only. The dimensions of the video frame in pixels.
127  */
128  int width;
129  int height;
130 
131  /**
132  * Video only. The aspect ratio (width / height) which a single pixel
133  * should have when displayed.
134  *
135  * When the aspect ratio is unknown / undefined, the numerator should be
136  * set to 0 (the denominator may have any value).
137  */
139 
140  /**
141  * Video only. The order of the fields in interlaced video.
142  */
144 
145  /**
146  * Video only. Additional colorspace characteristics.
147  */
153 
154  /**
155  * Video only. Number of delayed frames.
156  */
158 
159 #if FF_API_OLD_CHANNEL_LAYOUT
160  /**
161  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
162  * unknown or unspecified, otherwise the number of bits set must be equal to
163  * the channels field.
164  * @deprecated use ch_layout
165  */
167  uint64_t channel_layout;
168  /**
169  * Audio only. The number of audio channels.
170  * @deprecated use ch_layout.nb_channels
171  */
173  int channels;
174 #endif
175  /**
176  * Audio only. The number of audio samples per second.
177  */
179  /**
180  * Audio only. The number of bytes per coded audio frame, required by some
181  * formats.
182  *
183  * Corresponds to nBlockAlign in WAVEFORMATEX.
184  */
186  /**
187  * Audio only. Audio frame size, if known. Required by some formats to be static.
188  */
190 
191  /**
192  * Audio only. The amount of padding (in samples) inserted by the encoder at
193  * the beginning of the audio. I.e. this number of leading decoded samples
194  * must be discarded by the caller to get the original audio without leading
195  * padding.
196  */
198  /**
199  * Audio only. The amount of padding (in samples) appended by the encoder to
200  * the end of the audio. I.e. this number of decoded samples must be
201  * discarded by the caller from the end of the stream to get the original
202  * audio without any trailing padding.
203  */
205  /**
206  * Audio only. Number of samples to skip after a discontinuity.
207  */
209 
210  /**
211  * Audio only. The channel layout and number of channels.
212  */
215 
216 /**
217  * Allocate a new AVCodecParameters and set its fields to default values
218  * (unknown/invalid/0). The returned struct must be freed with
219  * avcodec_parameters_free().
220  */
222 
223 /**
224  * Free an AVCodecParameters instance and everything associated with it and
225  * write NULL to the supplied pointer.
226  */
228 
229 /**
230  * Copy the contents of src to dst. Any allocated fields in dst are freed and
231  * replaced with newly allocated duplicates of the corresponding fields in src.
232  *
233  * @return >= 0 on success, a negative AVERROR code on failure.
234  */
236 
237 /**
238  * This function is the same as av_get_audio_frame_duration(), except it works
239  * with AVCodecParameters instead of an AVCodecContext.
240  */
241 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
242 
243 /**
244  * @}
245  */
246 
247 #endif // AVCODEC_CODEC_PAR_H
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:76
AV_FIELD_PROGRESSIVE
@ AV_FIELD_PROGRESSIVE
Definition: codec_par.h:40
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:558
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
AVCodecParameters::color_space
enum AVColorSpace color_space
Definition: codec_par.h:151
rational.h
AVCodecParameters::seek_preroll
int seek_preroll
Audio only.
Definition: codec_par.h:208
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:66
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:533
AVCodecParameters::color_primaries
enum AVColorPrimaries color_primaries
Definition: codec_par.h:149
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:117
AV_FIELD_UNKNOWN
@ AV_FIELD_UNKNOWN
Definition: codec_par.h:39
AVCodecParameters::color_trc
enum AVColorTransferCharacteristic color_trc
Definition: codec_par.h:150
codec_id.h
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:189
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:38
AVCodecParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only.
Definition: codec_par.h:138
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
channels
channels
Definition: aptx.h:31
avcodec_parameters_free
void avcodec_parameters_free(AVCodecParameters **par)
Free an AVCodecParameters instance and everything associated with it and write NULL to the supplied p...
Definition: codec_par.c:63
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::level
int level
Definition: codec_par.h:123
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:80
AVMediaType
AVMediaType
Definition: avutil.h:199
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
av_get_audio_frame_duration2
int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes)
This function is the same as av_get_audio_frame_duration(), except it works with AVCodecParameters in...
Definition: utils.c:830
AVCodecParameters::profile
int profile
Codec-specific bitstream restrictions that the stream conforms to.
Definition: codec_par.h:122
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
AV_FIELD_TT
@ AV_FIELD_TT
Top coded_first, top displayed first.
Definition: codec_par.h:41
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:680
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:53
AVCodecParameters::height
int height
Definition: codec_par.h:129
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:185
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:587
AVCodecParameters::color_range
enum AVColorRange color_range
Video only.
Definition: codec_par.h:148
AVCodecParameters::field_order
enum AVFieldOrder field_order
Video only.
Definition: codec_par.h:143
pixfmt.h
AVCodecParameters::chroma_location
enum AVChromaLocation chroma_location
Definition: codec_par.h:152
AVCodecParameters::trailing_padding
int trailing_padding
Audio only.
Definition: codec_par.h:204
channel_layout.h
avutil.h
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:104
AVCodecParameters::video_delay
int video_delay
Video only.
Definition: codec_par.h:157
AVCodecParameters::format
int format
Definition: codec_par.h:86
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AV_FIELD_TB
@ AV_FIELD_TB
Top coded first, bottom displayed first.
Definition: codec_par.h:43
AV_FIELD_BB
@ AV_FIELD_BB
Bottom coded first, bottom displayed first.
Definition: codec_par.h:42
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:91
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:626
AV_FIELD_BT
@ AV_FIELD_BT
Bottom coded first, top displayed first.
Definition: codec_par.h:44
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:197
avcodec_parameters_copy
int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
Copy the contents of src to dst.
Definition: codec_par.c:74