ffmpeg.libavcodec.codec_par source code

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 module ffmpeg.libavcodec.codec_par;
21 
22 import ffmpeg.libavcodec;
23 import ffmpeg.libavutil;
24 
25 extern (C) @nogc nothrow:
26 
27 /**
28  * @addtogroup lavc_core
29  */
30 
31 enum AVFieldOrder
32 {
33     AV_FIELD_UNKNOWN = 0,
34     AV_FIELD_PROGRESSIVE = 1,
35     AV_FIELD_TT = 2, //< Top coded_first, top displayed first
36     AV_FIELD_BB = 3, //< Bottom coded first, bottom displayed first
37     AV_FIELD_TB = 4, //< Top coded first, bottom displayed first
38     AV_FIELD_BT = 5 //< Bottom coded first, top displayed first
39 }
40 
41 /**
42  * This struct describes the properties of an encoded stream.
43  *
44  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
45  * be allocated with avcodec_parameters_alloc() and freed with
46  * avcodec_parameters_free().
47  */
48 struct AVCodecParameters
49 {
50     /**
51      * General type of the encoded data.
52      */
53     AVMediaType codec_type;
54     /**
55      * Specific type of the encoded data (the codec used).
56      */
57     AVCodecID codec_id;
58     /**
59      * Additional information about the codec (corresponds to the AVI FOURCC).
60      */
61     uint codec_tag;
62 
63     /**
64      * Extra binary data needed for initializing the decoder, codec-dependent.
65      *
66      * Must be allocated with av_malloc() and will be freed by
67      * avcodec_parameters_free(). The allocated size of extradata must be at
68      * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
69      * bytes zeroed.
70      */
71     ubyte* extradata;
72     /**
73      * Size of the extradata content in bytes.
74      */
75     int extradata_size;
76 
77     /**
78      * - video: the pixel format, the value corresponds to enum AVPixelFormat.
79      * - audio: the sample format, the value corresponds to enum AVSampleFormat.
80      */
81     int format;
82 
83     /**
84      * The average bitrate of the encoded data (in bits per second).
85      */
86     long bit_rate;
87 
88     /**
89      * The number of bits per sample in the codedwords.
90      *
91      * This is basically the bitrate per sample. It is mandatory for a bunch of
92      * formats to actually decode them. It's the number of bits for one sample in
93      * the actual coded bitstream.
94      *
95      * This could be for example 4 for ADPCM
96      * For PCM formats this matches bits_per_raw_sample
97      * Can be 0
98      */
99     int bits_per_coded_sample;
100 
101     /**
102      * This is the number of valid bits in each output sample. If the
103      * sample format has more bits, the least significant bits are additional
104      * padding bits, which are always 0. Use right shifts to reduce the sample
105      * to its actual size. For example, audio formats with 24 bit samples will
106      * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
107      * To get the original sample use "(int32_t)sample >> 8"."
108      *
109      * For ADPCM this might be 12 or 16 or similar
110      * Can be 0
111      */
112     int bits_per_raw_sample;
113 
114     /**
115      * Codec-specific bitstream restrictions that the stream conforms to.
116      */
117     int profile;
118     int level;
119 
120     /**
121      * Video only. The dimensions of the video frame in pixels.
122      */
123     int width;
124     int height;
125 
126     /**
127      * Video only. The aspect ratio (width / height) which a single pixel
128      * should have when displayed.
129      *
130      * When the aspect ratio is unknown / undefined, the numerator should be
131      * set to 0 (the denominator may have any value).
132      */
133     AVRational sample_aspect_ratio;
134 
135     /**
136      * Video only. The order of the fields in interlaced video.
137      */
138     AVFieldOrder field_order;
139 
140     /**
141      * Video only. Additional colorspace characteristics.
142      */
143     AVColorRange color_range;
144     AVColorPrimaries color_primaries;
145     AVColorTransferCharacteristic color_trc;
146     AVColorSpace color_space;
147     AVChromaLocation chroma_location;
148 
149     /**
150      * Video only. Number of delayed frames.
151      */
152     int video_delay;
153 
154     /**
155      * Audio only. The channel layout bitmask. May be 0 if the channel layout is
156      * unknown or unspecified, otherwise the number of bits set must be equal to
157      * the channels field.
158      */
159     ulong channel_layout;
160     /**
161      * Audio only. The number of audio channels.
162      */
163     int channels;
164     /**
165      * Audio only. The number of audio samples per second.
166      */
167     int sample_rate;
168     /**
169      * Audio only. The number of bytes per coded audio frame, required by some
170      * formats.
171      *
172      * Corresponds to nBlockAlign in WAVEFORMATEX.
173      */
174     int block_align;
175     /**
176      * Audio only. Audio frame size, if known. Required by some formats to be static.
177      */
178     int frame_size;
179 
180     /**
181      * Audio only. The amount of padding (in samples) inserted by the encoder at
182      * the beginning of the audio. I.e. this number of leading decoded samples
183      * must be discarded by the caller to get the original audio without leading
184      * padding.
185      */
186     int initial_padding;
187     /**
188      * Audio only. The amount of padding (in samples) appended by the encoder to
189      * the end of the audio. I.e. this number of decoded samples must be
190      * discarded by the caller from the end of the stream to get the original
191      * audio without any trailing padding.
192      */
193     int trailing_padding;
194     /**
195      * Audio only. Number of samples to skip after a discontinuity.
196      */
197     int seek_preroll;
198 }
199 
200 /**
201  * Allocate a new AVCodecParameters and set its fields to default values
202  * (unknown/invalid/0). The returned struct must be freed with
203  * avcodec_parameters_free().
204  */
205 AVCodecParameters* avcodec_parameters_alloc ();
206 
207 /**
208  * Free an AVCodecParameters instance and everything associated with it and
209  * write NULL to the supplied pointer.
210  */
211 void avcodec_parameters_free (AVCodecParameters** par);
212 
213 /**
214  * Copy the contents of src to dst. Any allocated fields in dst are freed and
215  * replaced with newly allocated duplicates of the corresponding fields in src.
216  *
217  * @return >= 0 on success, a negative AVERROR code on failure.
218  */
219 int avcodec_parameters_copy (AVCodecParameters* dst, const(AVCodecParameters)* src);
220 
221 /**
222  * @}
223  */
224 
225 // AVCODEC_CODEC_PAR_H