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 
40  AV_FIELD_TT, //< Top coded_first, top displayed first
41  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
42  AV_FIELD_TB, //< Top coded first, bottom displayed first
43  AV_FIELD_BT, //< Bottom coded first, top displayed first
44 };
45 
46 /**
47  * This struct describes the properties of an encoded stream.
48  *
49  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
50  * be allocated with avcodec_parameters_alloc() and freed with
51  * avcodec_parameters_free().
52  */
53 typedef struct AVCodecParameters {
54  /**
55  * General type of the encoded data.
56  */
58  /**
59  * Specific type of the encoded data (the codec used).
60  */
62  /**
63  * Additional information about the codec (corresponds to the AVI FOURCC).
64  */
65  uint32_t codec_tag;
66 
67  /**
68  * Extra binary data needed for initializing the decoder, codec-dependent.
69  *
70  * Must be allocated with av_malloc() and will be freed by
71  * avcodec_parameters_free(). The allocated size of extradata must be at
72  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
73  * bytes zeroed.
74  */
75  uint8_t *extradata;
76  /**
77  * Size of the extradata content in bytes.
78  */
80 
81  /**
82  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
83  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
84  */
85  int format;
86 
87  /**
88  * The average bitrate of the encoded data (in bits per second).
89  */
90  int64_t bit_rate;
91 
92  /**
93  * The number of bits per sample in the codedwords.
94  *
95  * This is basically the bitrate per sample. It is mandatory for a bunch of
96  * formats to actually decode them. It's the number of bits for one sample in
97  * the actual coded bitstream.
98  *
99  * This could be for example 4 for ADPCM
100  * For PCM formats this matches bits_per_raw_sample
101  * Can be 0
102  */
104 
105  /**
106  * This is the number of valid bits in each output sample. If the
107  * sample format has more bits, the least significant bits are additional
108  * padding bits, which are always 0. Use right shifts to reduce the sample
109  * to its actual size. For example, audio formats with 24 bit samples will
110  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
111  * To get the original sample use "(int32_t)sample >> 8"."
112  *
113  * For ADPCM this might be 12 or 16 or similar
114  * Can be 0
115  */
117 
118  /**
119  * Codec-specific bitstream restrictions that the stream conforms to.
120  */
121  int profile;
122  int level;
123 
124  /**
125  * Video only. The dimensions of the video frame in pixels.
126  */
127  int width;
128  int height;
129 
130  /**
131  * Video only. The aspect ratio (width / height) which a single pixel
132  * should have when displayed.
133  *
134  * When the aspect ratio is unknown / undefined, the numerator should be
135  * set to 0 (the denominator may have any value).
136  */
138 
139  /**
140  * Video only. The order of the fields in interlaced video.
141  */
143 
144  /**
145  * Video only. Additional colorspace characteristics.
146  */
152 
153  /**
154  * Video only. Number of delayed frames.
155  */
157 
158 #if FF_API_OLD_CHANNEL_LAYOUT
159  /**
160  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
161  * unknown or unspecified, otherwise the number of bits set must be equal to
162  * the channels field.
163  * @deprecated use ch_layout
164  */
166  uint64_t channel_layout;
167  /**
168  * Audio only. The number of audio channels.
169  * @deprecated use ch_layout.nb_channels
170  */
172  int channels;
173 #endif
174  /**
175  * Audio only. The number of audio samples per second.
176  */
178  /**
179  * Audio only. The number of bytes per coded audio frame, required by some
180  * formats.
181  *
182  * Corresponds to nBlockAlign in WAVEFORMATEX.
183  */
185  /**
186  * Audio only. Audio frame size, if known. Required by some formats to be static.
187  */
189 
190  /**
191  * Audio only. The amount of padding (in samples) inserted by the encoder at
192  * the beginning of the audio. I.e. this number of leading decoded samples
193  * must be discarded by the caller to get the original audio without leading
194  * padding.
195  */
197  /**
198  * Audio only. The amount of padding (in samples) appended by the encoder to
199  * the end of the audio. I.e. this number of decoded samples must be
200  * discarded by the caller from the end of the stream to get the original
201  * audio without any trailing padding.
202  */
204  /**
205  * Audio only. Number of samples to skip after a discontinuity.
206  */
208 
209  /**
210  * Audio only. The channel layout and number of channels.
211  */
214 
215 /**
216  * Allocate a new AVCodecParameters and set its fields to default values
217  * (unknown/invalid/0). The returned struct must be freed with
218  * avcodec_parameters_free().
219  */
221 
222 /**
223  * Free an AVCodecParameters instance and everything associated with it and
224  * write NULL to the supplied pointer.
225  */
227 
228 /**
229  * Copy the contents of src to dst. Any allocated fields in dst are freed and
230  * replaced with newly allocated duplicates of the corresponding fields in src.
231  *
232  * @return >= 0 on success, a negative AVERROR code on failure.
233  */
235 
236 /**
237  * This function is the same as av_get_audio_frame_duration(), except it works
238  * with AVCodecParameters instead of an AVCodecContext.
239  */
240 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
241 
242 /**
243  * @}
244  */
245 
246 #endif // AVCODEC_CODEC_PAR_H
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:75
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:496
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:53
AVCodecParameters::color_space
enum AVColorSpace color_space
Definition: codec_par.h:150
rational.h
AVCodecParameters::seek_preroll
int seek_preroll
Audio only.
Definition: codec_par.h:207
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:471
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::color_primaries
enum AVColorPrimaries color_primaries
Definition: codec_par.h:148
AV_FIELD_TT
@ AV_FIELD_TT
Definition: codec_par.h:40
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
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:116
AV_FIELD_TB
@ AV_FIELD_TB
Definition: codec_par.h:42
AVCodecParameters::color_trc
enum AVColorTransferCharacteristic color_trc
Definition: codec_par.h:149
codec_id.h
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:188
AVCodecParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only.
Definition: codec_par.h:137
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:127
AV_FIELD_UNKNOWN
@ AV_FIELD_UNKNOWN
Definition: codec_par.h:38
channels
channels
Definition: aptx.h:32
AV_FIELD_BT
@ AV_FIELD_BT
Definition: codec_par.h:43
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::level
int level
Definition: codec_par.h:122
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:47
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:79
AVMediaType
AVMediaType
Definition: avutil.h:199
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:290
AVCodecParameters::profile
int profile
Codec-specific bitstream restrictions that the stream conforms to.
Definition: codec_par.h:121
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:618
AV_FIELD_BB
@ AV_FIELD_BB
Definition: codec_par.h:41
AVCodecParameters::height
int height
Definition: codec_par.h:128
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:184
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:525
AVCodecParameters::color_range
enum AVColorRange color_range
Video only.
Definition: codec_par.h:147
AVCodecParameters::field_order
enum AVFieldOrder field_order
Video only.
Definition: codec_par.h:142
pixfmt.h
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::chroma_location
enum AVChromaLocation chroma_location
Definition: codec_par.h:151
AVCodecParameters::trailing_padding
int trailing_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:74
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:103
AVCodecParameters::video_delay
int video_delay
Video only.
Definition: codec_par.h:156
AV_FIELD_PROGRESSIVE
@ AV_FIELD_PROGRESSIVE
Definition: codec_par.h:39
AVCodecParameters::format
int format
Definition: codec_par.h:85
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:37
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
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:90
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:564
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:196