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 #include "defs.h"
33 #include "packet.h"
34 
35 /**
36  * @addtogroup lavc_core
37  * @{
38  */
39 
40 /**
41  * This struct describes the properties of an encoded stream.
42  *
43  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
44  * be allocated with avcodec_parameters_alloc() and freed with
45  * avcodec_parameters_free().
46  */
47 typedef struct AVCodecParameters {
48  /**
49  * General type of the encoded data.
50  */
52  /**
53  * Specific type of the encoded data (the codec used).
54  */
56  /**
57  * Additional information about the codec (corresponds to the AVI FOURCC).
58  */
59  uint32_t codec_tag;
60 
61  /**
62  * Extra binary data needed for initializing the decoder, codec-dependent.
63  *
64  * Must be allocated with av_malloc() and will be freed by
65  * avcodec_parameters_free(). The allocated size of extradata must be at
66  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
67  * bytes zeroed.
68  */
69  uint8_t *extradata;
70  /**
71  * Size of the extradata content in bytes.
72  */
74 
75  /**
76  * Additional data associated with the entire stream.
77  *
78  * Should be allocated with av_packet_side_data_new() or
79  * av_packet_side_data_add(), and will be freed by avcodec_parameters_free().
80  */
82 
83  /**
84  * Amount of entries in @ref coded_side_data.
85  */
87 
88  /**
89  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
90  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
91  */
92  int format;
93 
94  /**
95  * The average bitrate of the encoded data (in bits per second).
96  */
97  int64_t bit_rate;
98 
99  /**
100  * The number of bits per sample in the codedwords.
101  *
102  * This is basically the bitrate per sample. It is mandatory for a bunch of
103  * formats to actually decode them. It's the number of bits for one sample in
104  * the actual coded bitstream.
105  *
106  * This could be for example 4 for ADPCM
107  * For PCM formats this matches bits_per_raw_sample
108  * Can be 0
109  */
111 
112  /**
113  * This is the number of valid bits in each output sample. If the
114  * sample format has more bits, the least significant bits are additional
115  * padding bits, which are always 0. Use right shifts to reduce the sample
116  * to its actual size. For example, audio formats with 24 bit samples will
117  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
118  * To get the original sample use "(int32_t)sample >> 8"."
119  *
120  * For ADPCM this might be 12 or 16 or similar
121  * Can be 0
122  */
124 
125  /**
126  * Codec-specific bitstream restrictions that the stream conforms to.
127  */
128  int profile;
129  int level;
130 
131  /**
132  * Video only. The dimensions of the video frame in pixels.
133  */
134  int width;
135  int height;
136 
137  /**
138  * Video only. The aspect ratio (width / height) which a single pixel
139  * should have when displayed.
140  *
141  * When the aspect ratio is unknown / undefined, the numerator should be
142  * set to 0 (the denominator may have any value).
143  */
145 
146  /**
147  * Video only. Number of frames per second, for streams with constant frame
148  * durations. Should be set to { 0, 1 } when some frames have differing
149  * durations or if the value is not known.
150  *
151  * @note This field correponds to values that are stored in codec-level
152  * headers and is typically overridden by container/transport-layer
153  * timestamps, when available. It should thus be used only as a last resort,
154  * when no higher-level timing information is available.
155  */
157 
158  /**
159  * Video only. The order of the fields in interlaced video.
160  */
162 
163  /**
164  * Video only. Additional colorspace characteristics.
165  */
171 
172  /**
173  * Video only. Number of delayed frames.
174  */
176 
177  /**
178  * Audio only. The channel layout and number of channels.
179  */
181  /**
182  * Audio only. The number of audio samples per second.
183  */
185  /**
186  * Audio only. The number of bytes per coded audio frame, required by some
187  * formats.
188  *
189  * Corresponds to nBlockAlign in WAVEFORMATEX.
190  */
192  /**
193  * Audio only. Audio frame size, if known. Required by some formats to be static.
194  */
196 
197  /**
198  * Audio only. The amount of padding (in samples) inserted by the encoder at
199  * the beginning of the audio. I.e. this number of leading decoded samples
200  * must be discarded by the caller to get the original audio without leading
201  * padding.
202  */
204  /**
205  * Audio only. The amount of padding (in samples) appended by the encoder to
206  * the end of the audio. I.e. this number of decoded samples must be
207  * discarded by the caller from the end of the stream to get the original
208  * audio without any trailing padding.
209  */
211  /**
212  * Audio only. Number of samples to skip after a discontinuity.
213  */
216 
217 /**
218  * Allocate a new AVCodecParameters and set its fields to default values
219  * (unknown/invalid/0). The returned struct must be freed with
220  * avcodec_parameters_free().
221  */
223 
224 /**
225  * Free an AVCodecParameters instance and everything associated with it and
226  * write NULL to the supplied pointer.
227  */
229 
230 /**
231  * Copy the contents of src to dst. Any allocated fields in dst are freed and
232  * replaced with newly allocated duplicates of the corresponding fields in src.
233  *
234  * @return >= 0 on success, a negative AVERROR code on failure.
235  */
237 
238 /**
239  * This function is the same as av_get_audio_frame_duration(), except it works
240  * with AVCodecParameters instead of an AVCodecContext.
241  */
242 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
243 
244 /**
245  * @}
246  */
247 
248 #endif // AVCODEC_CODEC_PAR_H
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:580
AVFieldOrder
AVFieldOrder
Definition: defs.h:198
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
rational.h
AVPacketSideData
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition: packet.h:373
AVCodecParameters::seek_preroll
int seek_preroll
Audio only.
Definition: codec_par.h:214
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
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:555
AVCodecParameters::color_primaries
enum AVColorPrimaries color_primaries
Definition: codec_par.h:167
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
codec_id.h
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
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
AVCodecParameters::nb_coded_side_data
int nb_coded_side_data
Amount of entries in coded_side_data.
Definition: codec_par.h:86
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:66
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::level
int level
Definition: codec_par.h:129
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
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:73
AVMediaType
AVMediaType
Definition: avutil.h:199
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
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:796
AVCodecParameters::profile
int profile
Codec-specific bitstream restrictions that the stream conforms to.
Definition: codec_par.h:128
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:702
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
packet.h
AVCodecParameters::height
int height
Definition: codec_par.h:135
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:609
AVCodecParameters::color_range
enum AVColorRange color_range
Video only.
Definition: codec_par.h:166
AVCodecParameters::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire stream.
Definition: codec_par.h:81
AVCodecParameters::field_order
enum AVFieldOrder field_order
Video only.
Definition: codec_par.h:161
pixfmt.h
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
channel_layout.h
defs.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:110
AVCodecParameters::video_delay
int video_delay
Video only.
Definition: codec_par.h:175
AVCodecParameters::format
int format
Definition: codec_par.h:92
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:648
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:203
avcodec_parameters_copy
int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
Copy the contents of src to dst.
Definition: codec_par.c:106