FFmpeg  4.4.1
channel_layout.h
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1 /*
2  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  * Copyright (c) 2008 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVUTIL_CHANNEL_LAYOUT_H
23 #define AVUTIL_CHANNEL_LAYOUT_H
24 
25 #include <stdint.h>
26 
27 /**
28  * @file
29  * audio channel layout utility functions
30  */
31 
32 /**
33  * @addtogroup lavu_audio
34  * @{
35  */
36 
37 /**
38  * @defgroup channel_masks Audio channel masks
39  *
40  * A channel layout is a 64-bits integer with a bit set for every channel.
41  * The number of bits set must be equal to the number of channels.
42  * The value 0 means that the channel layout is not known.
43  * @note this data structure is not powerful enough to handle channels
44  * combinations that have the same channel multiple times, such as
45  * dual-mono.
46  *
47  * @{
48  */
49 #define AV_CH_FRONT_LEFT 0x00000001
50 #define AV_CH_FRONT_RIGHT 0x00000002
51 #define AV_CH_FRONT_CENTER 0x00000004
52 #define AV_CH_LOW_FREQUENCY 0x00000008
53 #define AV_CH_BACK_LEFT 0x00000010
54 #define AV_CH_BACK_RIGHT 0x00000020
55 #define AV_CH_FRONT_LEFT_OF_CENTER 0x00000040
56 #define AV_CH_FRONT_RIGHT_OF_CENTER 0x00000080
57 #define AV_CH_BACK_CENTER 0x00000100
58 #define AV_CH_SIDE_LEFT 0x00000200
59 #define AV_CH_SIDE_RIGHT 0x00000400
60 #define AV_CH_TOP_CENTER 0x00000800
61 #define AV_CH_TOP_FRONT_LEFT 0x00001000
62 #define AV_CH_TOP_FRONT_CENTER 0x00002000
63 #define AV_CH_TOP_FRONT_RIGHT 0x00004000
64 #define AV_CH_TOP_BACK_LEFT 0x00008000
65 #define AV_CH_TOP_BACK_CENTER 0x00010000
66 #define AV_CH_TOP_BACK_RIGHT 0x00020000
67 #define AV_CH_STEREO_LEFT 0x20000000 ///< Stereo downmix.
68 #define AV_CH_STEREO_RIGHT 0x40000000 ///< See AV_CH_STEREO_LEFT.
69 #define AV_CH_WIDE_LEFT 0x0000000080000000ULL
70 #define AV_CH_WIDE_RIGHT 0x0000000100000000ULL
71 #define AV_CH_SURROUND_DIRECT_LEFT 0x0000000200000000ULL
72 #define AV_CH_SURROUND_DIRECT_RIGHT 0x0000000400000000ULL
73 #define AV_CH_LOW_FREQUENCY_2 0x0000000800000000ULL
74 #define AV_CH_TOP_SIDE_LEFT 0x0000001000000000ULL
75 #define AV_CH_TOP_SIDE_RIGHT 0x0000002000000000ULL
76 #define AV_CH_BOTTOM_FRONT_CENTER 0x0000004000000000ULL
77 #define AV_CH_BOTTOM_FRONT_LEFT 0x0000008000000000ULL
78 #define AV_CH_BOTTOM_FRONT_RIGHT 0x0000010000000000ULL
79 
80 /** Channel mask value used for AVCodecContext.request_channel_layout
81  to indicate that the user requests the channel order of the decoder output
82  to be the native codec channel order. */
83 #define AV_CH_LAYOUT_NATIVE 0x8000000000000000ULL
84 
85 /**
86  * @}
87  * @defgroup channel_mask_c Audio channel layouts
88  * @{
89  * */
90 #define AV_CH_LAYOUT_MONO (AV_CH_FRONT_CENTER)
91 #define AV_CH_LAYOUT_STEREO (AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT)
92 #define AV_CH_LAYOUT_2POINT1 (AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY)
93 #define AV_CH_LAYOUT_2_1 (AV_CH_LAYOUT_STEREO|AV_CH_BACK_CENTER)
94 #define AV_CH_LAYOUT_SURROUND (AV_CH_LAYOUT_STEREO|AV_CH_FRONT_CENTER)
95 #define AV_CH_LAYOUT_3POINT1 (AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY)
96 #define AV_CH_LAYOUT_4POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_CENTER)
97 #define AV_CH_LAYOUT_4POINT1 (AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY)
98 #define AV_CH_LAYOUT_2_2 (AV_CH_LAYOUT_STEREO|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
99 #define AV_CH_LAYOUT_QUAD (AV_CH_LAYOUT_STEREO|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
100 #define AV_CH_LAYOUT_5POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
101 #define AV_CH_LAYOUT_5POINT1 (AV_CH_LAYOUT_5POINT0|AV_CH_LOW_FREQUENCY)
102 #define AV_CH_LAYOUT_5POINT0_BACK (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
103 #define AV_CH_LAYOUT_5POINT1_BACK (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_LOW_FREQUENCY)
104 #define AV_CH_LAYOUT_6POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_CENTER)
105 #define AV_CH_LAYOUT_6POINT0_FRONT (AV_CH_LAYOUT_2_2|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
106 #define AV_CH_LAYOUT_HEXAGONAL (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_BACK_CENTER)
107 #define AV_CH_LAYOUT_6POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_CENTER)
108 #define AV_CH_LAYOUT_6POINT1_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER)
109 #define AV_CH_LAYOUT_6POINT1_FRONT (AV_CH_LAYOUT_6POINT0_FRONT|AV_CH_LOW_FREQUENCY)
110 #define AV_CH_LAYOUT_7POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
111 #define AV_CH_LAYOUT_7POINT0_FRONT (AV_CH_LAYOUT_5POINT0|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
112 #define AV_CH_LAYOUT_7POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
113 #define AV_CH_LAYOUT_7POINT1_WIDE (AV_CH_LAYOUT_5POINT1|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
114 #define AV_CH_LAYOUT_7POINT1_WIDE_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
115 #define AV_CH_LAYOUT_OCTAGONAL (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_CENTER|AV_CH_BACK_RIGHT)
116 #define AV_CH_LAYOUT_HEXADECAGONAL (AV_CH_LAYOUT_OCTAGONAL|AV_CH_WIDE_LEFT|AV_CH_WIDE_RIGHT|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT|AV_CH_TOP_BACK_CENTER|AV_CH_TOP_FRONT_CENTER|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT)
117 #define AV_CH_LAYOUT_STEREO_DOWNMIX (AV_CH_STEREO_LEFT|AV_CH_STEREO_RIGHT)
118 #define AV_CH_LAYOUT_22POINT2 (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER|AV_CH_BACK_CENTER|AV_CH_LOW_FREQUENCY_2|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT|AV_CH_TOP_FRONT_CENTER|AV_CH_TOP_CENTER|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT|AV_CH_TOP_SIDE_LEFT|AV_CH_TOP_SIDE_RIGHT|AV_CH_TOP_BACK_CENTER|AV_CH_BOTTOM_FRONT_CENTER|AV_CH_BOTTOM_FRONT_LEFT|AV_CH_BOTTOM_FRONT_RIGHT)
119 
129 };
130 
131 /**
132  * Return a channel layout id that matches name, or 0 if no match is found.
133  *
134  * name can be one or several of the following notations,
135  * separated by '+' or '|':
136  * - the name of an usual channel layout (mono, stereo, 4.0, quad, 5.0,
137  * 5.0(side), 5.1, 5.1(side), 7.1, 7.1(wide), downmix);
138  * - the name of a single channel (FL, FR, FC, LFE, BL, BR, FLC, FRC, BC,
139  * SL, SR, TC, TFL, TFC, TFR, TBL, TBC, TBR, DL, DR);
140  * - a number of channels, in decimal, followed by 'c', yielding
141  * the default channel layout for that number of channels (@see
142  * av_get_default_channel_layout);
143  * - a channel layout mask, in hexadecimal starting with "0x" (see the
144  * AV_CH_* macros).
145  *
146  * Example: "stereo+FC" = "2c+FC" = "2c+1c" = "0x7"
147  */
148 uint64_t av_get_channel_layout(const char *name);
149 
150 /**
151  * Return a channel layout and the number of channels based on the specified name.
152  *
153  * This function is similar to (@see av_get_channel_layout), but can also parse
154  * unknown channel layout specifications.
155  *
156  * @param[in] name channel layout specification string
157  * @param[out] channel_layout parsed channel layout (0 if unknown)
158  * @param[out] nb_channels number of channels
159  *
160  * @return 0 on success, AVERROR(EINVAL) if the parsing fails.
161  */
162 int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels);
163 
164 /**
165  * Return a description of a channel layout.
166  * If nb_channels is <= 0, it is guessed from the channel_layout.
167  *
168  * @param buf put here the string containing the channel layout
169  * @param buf_size size in bytes of the buffer
170  */
171 void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout);
172 
173 struct AVBPrint;
174 /**
175  * Append a description of a channel layout to a bprint buffer.
176  */
177 void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout);
178 
179 /**
180  * Return the number of channels in the channel layout.
181  */
182 int av_get_channel_layout_nb_channels(uint64_t channel_layout);
183 
184 /**
185  * Return default channel layout for a given number of channels.
186  */
187 int64_t av_get_default_channel_layout(int nb_channels);
188 
189 /**
190  * Get the index of a channel in channel_layout.
191  *
192  * @param channel a channel layout describing exactly one channel which must be
193  * present in channel_layout.
194  *
195  * @return index of channel in channel_layout on success, a negative AVERROR
196  * on error.
197  */
198 int av_get_channel_layout_channel_index(uint64_t channel_layout,
199  uint64_t channel);
200 
201 /**
202  * Get the channel with the given index in channel_layout.
203  */
204 uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
205 
206 /**
207  * Get the name of a given channel.
208  *
209  * @return channel name on success, NULL on error.
210  */
211 const char *av_get_channel_name(uint64_t channel);
212 
213 /**
214  * Get the description of a given channel.
215  *
216  * @param channel a channel layout with a single channel
217  * @return channel description on success, NULL on error
218  */
219 const char *av_get_channel_description(uint64_t channel);
220 
221 /**
222  * Get the value and name of a standard channel layout.
223  *
224  * @param[in] index index in an internal list, starting at 0
225  * @param[out] layout channel layout mask
226  * @param[out] name name of the layout
227  * @return 0 if the layout exists,
228  * <0 if index is beyond the limits
229  */
230 int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
231  const char **name);
232 
233 /**
234  * @}
235  * @}
236  */
237 
238 #endif /* AVUTIL_CHANNEL_LAYOUT_H */
int av_get_standard_channel_layout(unsigned index, uint64_t *layout, const char **name)
Get the value and name of a standard channel layout.
int av_get_channel_layout_channel_index(uint64_t channel_layout, uint64_t channel)
Get the index of a channel in channel_layout.
uint64_t av_get_channel_layout(const char *name)
Return a channel layout id that matches name, or 0 if no match is found.
void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout)
Append a description of a channel layout to a bprint buffer.
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
AVMatrixEncoding
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
int64_t av_get_default_channel_layout(int nb_channels)
Return default channel layout for a given number of channels.
int av_get_extended_channel_layout(const char *name, uint64_t *channel_layout, int *nb_channels)
Return a channel layout and the number of channels based on the specified name.
const char * av_get_channel_description(uint64_t channel)
Get the description of a given channel.
uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
Get the channel with the given index in channel_layout.
const char * av_get_channel_name(uint64_t channel)
Get the name of a given channel.
@ AV_MATRIX_ENCODING_DPLIIX
@ AV_MATRIX_ENCODING_NONE
@ AV_MATRIX_ENCODING_DOLBY
@ AV_MATRIX_ENCODING_DPLII
@ AV_MATRIX_ENCODING_NB
@ AV_MATRIX_ENCODING_DPLIIZ
@ AV_MATRIX_ENCODING_DOLBYEX
@ AV_MATRIX_ENCODING_DOLBYHEADPHONE