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 #include <stdlib.h> 27 28 #include "version.h" 29 #include "attributes.h" 30 31 /** 32 * @file 33 * audio channel layout utility functions 34 */ 35 36 /** 37 * @addtogroup lavu_audio 38 * @{ 39 */ 40 41 enum AVChannel { 42 ///< Invalid channel index 43 AV_CHAN_NONE = -1, 44 AV_CHAN_FRONT_LEFT, 45 AV_CHAN_FRONT_RIGHT, 46 AV_CHAN_FRONT_CENTER, 47 AV_CHAN_LOW_FREQUENCY, 48 AV_CHAN_BACK_LEFT, 49 AV_CHAN_BACK_RIGHT, 50 AV_CHAN_FRONT_LEFT_OF_CENTER, 51 AV_CHAN_FRONT_RIGHT_OF_CENTER, 52 AV_CHAN_BACK_CENTER, 53 AV_CHAN_SIDE_LEFT, 54 AV_CHAN_SIDE_RIGHT, 55 AV_CHAN_TOP_CENTER, 56 AV_CHAN_TOP_FRONT_LEFT, 57 AV_CHAN_TOP_FRONT_CENTER, 58 AV_CHAN_TOP_FRONT_RIGHT, 59 AV_CHAN_TOP_BACK_LEFT, 60 AV_CHAN_TOP_BACK_CENTER, 61 AV_CHAN_TOP_BACK_RIGHT, 62 /** Stereo downmix. */ 63 AV_CHAN_STEREO_LEFT = 29, 64 /** See above. */ 65 AV_CHAN_STEREO_RIGHT, 66 AV_CHAN_WIDE_LEFT, 67 AV_CHAN_WIDE_RIGHT, 68 AV_CHAN_SURROUND_DIRECT_LEFT, 69 AV_CHAN_SURROUND_DIRECT_RIGHT, 70 AV_CHAN_LOW_FREQUENCY_2, 71 AV_CHAN_TOP_SIDE_LEFT, 72 AV_CHAN_TOP_SIDE_RIGHT, 73 AV_CHAN_BOTTOM_FRONT_CENTER, 74 AV_CHAN_BOTTOM_FRONT_LEFT, 75 AV_CHAN_BOTTOM_FRONT_RIGHT, 76 77 /** Channel is empty can be safely skipped. */ 78 AV_CHAN_UNUSED = 0x200, 79 80 /** Channel contains data, but its position is unknown. */ 81 AV_CHAN_UNKNOWN = 0x300, 82 83 /** 84 * Range of channels between AV_CHAN_AMBISONIC_BASE and 85 * AV_CHAN_AMBISONIC_END represent Ambisonic components using the ACN system. 86 * 87 * Given a channel id <i> between AV_CHAN_AMBISONIC_BASE and 88 * AV_CHAN_AMBISONIC_END (inclusive), the ACN index of the channel <n> is 89 * <n> = <i> - AV_CHAN_AMBISONIC_BASE. 90 * 91 * @note these values are only used for AV_CHANNEL_ORDER_CUSTOM channel 92 * orderings, the AV_CHANNEL_ORDER_AMBISONIC ordering orders the channels 93 * implicitly by their position in the stream. 94 */ 95 AV_CHAN_AMBISONIC_BASE = 0x400, 96 // leave space for 1024 ids, which correspond to maximum order-32 harmonics, 97 // which should be enough for the foreseeable use cases 98 AV_CHAN_AMBISONIC_END = 0x7ff, 99 }; 100 101 enum AVChannelOrder { 102 /** 103 * Only the channel count is specified, without any further information 104 * about the channel order. 105 */ 106 AV_CHANNEL_ORDER_UNSPEC, 107 /** 108 * The native channel order, i.e. the channels are in the same order in 109 * which they are defined in the AVChannel enum. This supports up to 63 110 * different channels. 111 */ 112 AV_CHANNEL_ORDER_NATIVE, 113 /** 114 * The channel order does not correspond to any other predefined order and 115 * is stored as an explicit map. For example, this could be used to support 116 * layouts with 64 or more channels, or with empty/skipped (AV_CHAN_SILENCE) 117 * channels at arbitrary positions. 118 */ 119 AV_CHANNEL_ORDER_CUSTOM, 120 /** 121 * The audio is represented as the decomposition of the sound field into 122 * spherical harmonics. Each channel corresponds to a single expansion 123 * component. Channels are ordered according to ACN (Ambisonic Channel 124 * Number). 125 * 126 * The channel with the index n in the stream contains the spherical 127 * harmonic of degree l and order m given by 128 * @code{.unparsed} 129 * l = floor(sqrt(n)), 130 * m = n - l * (l + 1). 131 * @endcode 132 * 133 * Conversely given a spherical harmonic of degree l and order m, the 134 * corresponding channel index n is given by 135 * @code{.unparsed} 136 * n = l * (l + 1) + m. 137 * @endcode 138 * 139 * Normalization is assumed to be SN3D (Schmidt Semi-Normalization) 140 * as defined in AmbiX format $ 2.1. 141 */ 142 AV_CHANNEL_ORDER_AMBISONIC, 143 }; 144 145 146 /** 147 * @defgroup channel_masks Audio channel masks 148 * 149 * A channel layout is a 64-bits integer with a bit set for every channel. 150 * The number of bits set must be equal to the number of channels. 151 * The value 0 means that the channel layout is not known. 152 * @note this data structure is not powerful enough to handle channels 153 * combinations that have the same channel multiple times, such as 154 * dual-mono. 155 * 156 * @{ 157 */ 158 #define AV_CH_FRONT_LEFT (1ULL << AV_CHAN_FRONT_LEFT ) 159 #define AV_CH_FRONT_RIGHT (1ULL << AV_CHAN_FRONT_RIGHT ) 160 #define AV_CH_FRONT_CENTER (1ULL << AV_CHAN_FRONT_CENTER ) 161 #define AV_CH_LOW_FREQUENCY (1ULL << AV_CHAN_LOW_FREQUENCY ) 162 #define AV_CH_BACK_LEFT (1ULL << AV_CHAN_BACK_LEFT ) 163 #define AV_CH_BACK_RIGHT (1ULL << AV_CHAN_BACK_RIGHT ) 164 #define AV_CH_FRONT_LEFT_OF_CENTER (1ULL << AV_CHAN_FRONT_LEFT_OF_CENTER ) 165 #define AV_CH_FRONT_RIGHT_OF_CENTER (1ULL << AV_CHAN_FRONT_RIGHT_OF_CENTER) 166 #define AV_CH_BACK_CENTER (1ULL << AV_CHAN_BACK_CENTER ) 167 #define AV_CH_SIDE_LEFT (1ULL << AV_CHAN_SIDE_LEFT ) 168 #define AV_CH_SIDE_RIGHT (1ULL << AV_CHAN_SIDE_RIGHT ) 169 #define AV_CH_TOP_CENTER (1ULL << AV_CHAN_TOP_CENTER ) 170 #define AV_CH_TOP_FRONT_LEFT (1ULL << AV_CHAN_TOP_FRONT_LEFT ) 171 #define AV_CH_TOP_FRONT_CENTER (1ULL << AV_CHAN_TOP_FRONT_CENTER ) 172 #define AV_CH_TOP_FRONT_RIGHT (1ULL << AV_CHAN_TOP_FRONT_RIGHT ) 173 #define AV_CH_TOP_BACK_LEFT (1ULL << AV_CHAN_TOP_BACK_LEFT ) 174 #define AV_CH_TOP_BACK_CENTER (1ULL << AV_CHAN_TOP_BACK_CENTER ) 175 #define AV_CH_TOP_BACK_RIGHT (1ULL << AV_CHAN_TOP_BACK_RIGHT ) 176 #define AV_CH_STEREO_LEFT (1ULL << AV_CHAN_STEREO_LEFT ) 177 #define AV_CH_STEREO_RIGHT (1ULL << AV_CHAN_STEREO_RIGHT ) 178 #define AV_CH_WIDE_LEFT (1ULL << AV_CHAN_WIDE_LEFT ) 179 #define AV_CH_WIDE_RIGHT (1ULL << AV_CHAN_WIDE_RIGHT ) 180 #define AV_CH_SURROUND_DIRECT_LEFT (1ULL << AV_CHAN_SURROUND_DIRECT_LEFT ) 181 #define AV_CH_SURROUND_DIRECT_RIGHT (1ULL << AV_CHAN_SURROUND_DIRECT_RIGHT) 182 #define AV_CH_LOW_FREQUENCY_2 (1ULL << AV_CHAN_LOW_FREQUENCY_2 ) 183 #define AV_CH_TOP_SIDE_LEFT (1ULL << AV_CHAN_TOP_SIDE_LEFT ) 184 #define AV_CH_TOP_SIDE_RIGHT (1ULL << AV_CHAN_TOP_SIDE_RIGHT ) 185 #define AV_CH_BOTTOM_FRONT_CENTER (1ULL << AV_CHAN_BOTTOM_FRONT_CENTER ) 186 #define AV_CH_BOTTOM_FRONT_LEFT (1ULL << AV_CHAN_BOTTOM_FRONT_LEFT ) 187 #define AV_CH_BOTTOM_FRONT_RIGHT (1ULL << AV_CHAN_BOTTOM_FRONT_RIGHT ) 188 189 #if FF_API_OLD_CHANNEL_LAYOUT 190 /** Channel mask value used for AVCodecContext.request_channel_layout 191 to indicate that the user requests the channel order of the decoder output 192 to be the native codec channel order. 193 @deprecated channel order is now indicated in a special field in 194 AVChannelLayout 195 */ 196 #define AV_CH_LAYOUT_NATIVE 0x8000000000000000ULL 197 #endif 198 199 /** 200 * @} 201 * @defgroup channel_mask_c Audio channel layouts 202 * @{ 203 * */ 204 #define AV_CH_LAYOUT_MONO (AV_CH_FRONT_CENTER) 205 #define AV_CH_LAYOUT_STEREO (AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT) 206 #define AV_CH_LAYOUT_2POINT1 (AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY) 207 #define AV_CH_LAYOUT_2_1 (AV_CH_LAYOUT_STEREO|AV_CH_BACK_CENTER) 208 #define AV_CH_LAYOUT_SURROUND (AV_CH_LAYOUT_STEREO|AV_CH_FRONT_CENTER) 209 #define AV_CH_LAYOUT_3POINT1 (AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY) 210 #define AV_CH_LAYOUT_4POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_CENTER) 211 #define AV_CH_LAYOUT_4POINT1 (AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY) 212 #define AV_CH_LAYOUT_2_2 (AV_CH_LAYOUT_STEREO|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT) 213 #define AV_CH_LAYOUT_QUAD (AV_CH_LAYOUT_STEREO|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT) 214 #define AV_CH_LAYOUT_5POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT) 215 #define AV_CH_LAYOUT_5POINT1 (AV_CH_LAYOUT_5POINT0|AV_CH_LOW_FREQUENCY) 216 #define AV_CH_LAYOUT_5POINT0_BACK (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT) 217 #define AV_CH_LAYOUT_5POINT1_BACK (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_LOW_FREQUENCY) 218 #define AV_CH_LAYOUT_6POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_CENTER) 219 #define AV_CH_LAYOUT_6POINT0_FRONT (AV_CH_LAYOUT_2_2|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER) 220 #define AV_CH_LAYOUT_HEXAGONAL (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_BACK_CENTER) 221 #define AV_CH_LAYOUT_6POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_CENTER) 222 #define AV_CH_LAYOUT_6POINT1_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER) 223 #define AV_CH_LAYOUT_6POINT1_FRONT (AV_CH_LAYOUT_6POINT0_FRONT|AV_CH_LOW_FREQUENCY) 224 #define AV_CH_LAYOUT_7POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT) 225 #define AV_CH_LAYOUT_7POINT0_FRONT (AV_CH_LAYOUT_5POINT0|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER) 226 #define AV_CH_LAYOUT_7POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT) 227 #define AV_CH_LAYOUT_7POINT1_WIDE (AV_CH_LAYOUT_5POINT1|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER) 228 #define AV_CH_LAYOUT_7POINT1_WIDE_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER) 229 #define AV_CH_LAYOUT_OCTAGONAL (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_CENTER|AV_CH_BACK_RIGHT) 230 #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) 231 #define AV_CH_LAYOUT_STEREO_DOWNMIX (AV_CH_STEREO_LEFT|AV_CH_STEREO_RIGHT) 232 #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) 233 234 enum AVMatrixEncoding { 235 AV_MATRIX_ENCODING_NONE, 236 AV_MATRIX_ENCODING_DOLBY, 237 AV_MATRIX_ENCODING_DPLII, 238 AV_MATRIX_ENCODING_DPLIIX, 239 AV_MATRIX_ENCODING_DPLIIZ, 240 AV_MATRIX_ENCODING_DOLBYEX, 241 AV_MATRIX_ENCODING_DOLBYHEADPHONE, 242 AV_MATRIX_ENCODING_NB 243 }; 244 245 /** 246 * @} 247 */ 248 249 /** 250 * An AVChannelCustom defines a single channel within a custom order layout 251 * 252 * Unlike most structures in FFmpeg, sizeof(AVChannelCustom) is a part of the 253 * public ABI. 254 * 255 * No new fields may be added to it without a major version bump. 256 */ 257 typedef struct AVChannelCustom { 258 enum AVChannel id; 259 char name[16]; 260 void *opaque; 261 } AVChannelCustom; 262 263 /** 264 * An AVChannelLayout holds information about the channel layout of audio data. 265 * 266 * A channel layout here is defined as a set of channels ordered in a specific 267 * way (unless the channel order is AV_CHANNEL_ORDER_UNSPEC, in which case an 268 * AVChannelLayout carries only the channel count). 269 * 270 * Unlike most structures in Libav, sizeof(AVChannelLayout) is a part of the 271 * public ABI and may be used by the caller. E.g. it may be allocated on stack 272 * or embedded in caller-defined structs. 273 * 274 * AVChannelLayout can be initialized as follows: 275 * - default initialization with {0}, followed by setting all used fields 276 * correctly; 277 * - by assigning one of the predefined AV_CHANNEL_LAYOUT_* initializers; 278 * - with a constructor function, such as av_channel_layout_default(), 279 * av_channel_layout_from_mask() or av_channel_layout_from_string(). 280 * 281 * The channel layout must be unitialized with av_channel_layout_uninit() 282 * 283 * Copying an AVChannelLayout via assigning is forbidden, 284 * av_channel_layout_copy() must be used instead (and its return value should 285 * be checked) 286 * 287 * No new fields may be added to it without a major version bump, except for 288 * new elements of the union fitting in sizeof(uint64_t). 289 */ 290 typedef struct AVChannelLayout { 291 /** 292 * Channel order used in this layout. 293 * This is a mandatory field. 294 */ 295 enum AVChannelOrder order; 296 297 /** 298 * Number of channels in this layout. Mandatory field. 299 */ 300 int nb_channels; 301 302 /** 303 * Details about which channels are present in this layout. 304 * For AV_CHANNEL_ORDER_UNSPEC, this field is undefined and must not be 305 * used. 306 */ 307 union { 308 /** 309 * This member must be used for AV_CHANNEL_ORDER_NATIVE, and may be used 310 * for AV_CHANNEL_ORDER_AMBISONIC to signal non-diegetic channels. 311 * It is a bitmask, where the position of each set bit means that the 312 * AVChannel with the corresponding value is present. 313 * 314 * I.e. when (mask & (1 << AV_CHAN_FOO)) is non-zero, then AV_CHAN_FOO 315 * is present in the layout. Otherwise it is not present. 316 * 317 * @note when a channel layout using a bitmask is constructed or 318 * modified manually (i.e. not using any of the av_channel_layout_* 319 * functions), the code doing it must ensure that the number of set bits 320 * is equal to nb_channels. 321 */ 322 uint64_t mask; 323 /** 324 * This member must be used when the channel order is 325 * AV_CHANNEL_ORDER_CUSTOM. It is a nb_channels-sized array, with each 326 * element signalling the presence of the AVChannel with the 327 * corresponding value in map[i].id. 328 * 329 * I.e. when map[i].id is equal to AV_CHAN_FOO, then AV_CH_FOO is the 330 * i-th channel in the audio data. 331 * 332 * When map[i].id is in the range between AV_CHAN_AMBISONIC_BASE and 333 * AV_CHAN_AMBISONIC_END (inclusive), the channel contains an ambisonic 334 * component with ACN index (as defined above) 335 * n = map[i].id - AV_CHAN_AMBISONIC_BASE. 336 * 337 * map[i].name may be filled with a 0-terminated string, in which case 338 * it will be used for the purpose of identifying the channel with the 339 * convenience functions below. Otherise it must be zeroed. 340 */ 341 AVChannelCustom *map; 342 } u; 343 344 /** 345 * For some private data of the user. 346 */ 347 void *opaque; 348 } AVChannelLayout; 349 350 #define AV_CHANNEL_LAYOUT_MASK(nb, m) \ 351 { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = (nb), .u = { .mask = (m) }} 352 353 #define AV_CHANNEL_LAYOUT_MONO AV_CHANNEL_LAYOUT_MASK(1, AV_CH_LAYOUT_MONO) 354 #define AV_CHANNEL_LAYOUT_STEREO AV_CHANNEL_LAYOUT_MASK(2, AV_CH_LAYOUT_STEREO) 355 #define AV_CHANNEL_LAYOUT_2POINT1 AV_CHANNEL_LAYOUT_MASK(3, AV_CH_LAYOUT_2POINT1) 356 #define AV_CHANNEL_LAYOUT_2_1 AV_CHANNEL_LAYOUT_MASK(3, AV_CH_LAYOUT_2_1) 357 #define AV_CHANNEL_LAYOUT_SURROUND AV_CHANNEL_LAYOUT_MASK(3, AV_CH_LAYOUT_SURROUND) 358 #define AV_CHANNEL_LAYOUT_3POINT1 AV_CHANNEL_LAYOUT_MASK(4, AV_CH_LAYOUT_3POINT1) 359 #define AV_CHANNEL_LAYOUT_4POINT0 AV_CHANNEL_LAYOUT_MASK(4, AV_CH_LAYOUT_4POINT0) 360 #define AV_CHANNEL_LAYOUT_4POINT1 AV_CHANNEL_LAYOUT_MASK(5, AV_CH_LAYOUT_4POINT1) 361 #define AV_CHANNEL_LAYOUT_2_2 AV_CHANNEL_LAYOUT_MASK(4, AV_CH_LAYOUT_2_2) 362 #define AV_CHANNEL_LAYOUT_QUAD AV_CHANNEL_LAYOUT_MASK(4, AV_CH_LAYOUT_QUAD) 363 #define AV_CHANNEL_LAYOUT_5POINT0 AV_CHANNEL_LAYOUT_MASK(5, AV_CH_LAYOUT_5POINT0) 364 #define AV_CHANNEL_LAYOUT_5POINT1 AV_CHANNEL_LAYOUT_MASK(6, AV_CH_LAYOUT_5POINT1) 365 #define AV_CHANNEL_LAYOUT_5POINT0_BACK AV_CHANNEL_LAYOUT_MASK(5, AV_CH_LAYOUT_5POINT0_BACK) 366 #define AV_CHANNEL_LAYOUT_5POINT1_BACK AV_CHANNEL_LAYOUT_MASK(6, AV_CH_LAYOUT_5POINT1_BACK) 367 #define AV_CHANNEL_LAYOUT_6POINT0 AV_CHANNEL_LAYOUT_MASK(6, AV_CH_LAYOUT_6POINT0) 368 #define AV_CHANNEL_LAYOUT_6POINT0_FRONT AV_CHANNEL_LAYOUT_MASK(6, AV_CH_LAYOUT_6POINT0_FRONT) 369 #define AV_CHANNEL_LAYOUT_HEXAGONAL AV_CHANNEL_LAYOUT_MASK(6, AV_CH_LAYOUT_HEXAGONAL) 370 #define AV_CHANNEL_LAYOUT_6POINT1 AV_CHANNEL_LAYOUT_MASK(7, AV_CH_LAYOUT_6POINT1) 371 #define AV_CHANNEL_LAYOUT_6POINT1_BACK AV_CHANNEL_LAYOUT_MASK(7, AV_CH_LAYOUT_6POINT1_BACK) 372 #define AV_CHANNEL_LAYOUT_6POINT1_FRONT AV_CHANNEL_LAYOUT_MASK(7, AV_CH_LAYOUT_6POINT1_FRONT) 373 #define AV_CHANNEL_LAYOUT_7POINT0 AV_CHANNEL_LAYOUT_MASK(7, AV_CH_LAYOUT_7POINT0) 374 #define AV_CHANNEL_LAYOUT_7POINT0_FRONT AV_CHANNEL_LAYOUT_MASK(7, AV_CH_LAYOUT_7POINT0_FRONT) 375 #define AV_CHANNEL_LAYOUT_7POINT1 AV_CHANNEL_LAYOUT_MASK(8, AV_CH_LAYOUT_7POINT1) 376 #define AV_CHANNEL_LAYOUT_7POINT1_WIDE AV_CHANNEL_LAYOUT_MASK(8, AV_CH_LAYOUT_7POINT1_WIDE) 377 #define AV_CHANNEL_LAYOUT_7POINT1_WIDE_BACK AV_CHANNEL_LAYOUT_MASK(8, AV_CH_LAYOUT_7POINT1_WIDE_BACK) 378 #define AV_CHANNEL_LAYOUT_OCTAGONAL AV_CHANNEL_LAYOUT_MASK(8, AV_CH_LAYOUT_OCTAGONAL) 379 #define AV_CHANNEL_LAYOUT_HEXADECAGONAL AV_CHANNEL_LAYOUT_MASK(16, AV_CH_LAYOUT_HEXADECAGONAL) 380 #define AV_CHANNEL_LAYOUT_STEREO_DOWNMIX AV_CHANNEL_LAYOUT_MASK(2, AV_CH_LAYOUT_STEREO_DOWNMIX) 381 #define AV_CHANNEL_LAYOUT_22POINT2 AV_CHANNEL_LAYOUT_MASK(24, AV_CH_LAYOUT_22POINT2) 382 #define AV_CHANNEL_LAYOUT_AMBISONIC_FIRST_ORDER \ 383 { .order = AV_CHANNEL_ORDER_AMBISONIC, .nb_channels = 4, .u = { .mask = 0 }} 384 385 struct AVBPrint; 386 387 #if FF_API_OLD_CHANNEL_LAYOUT 388 /** 389 * Return a channel layout id that matches name, or 0 if no match is found. 390 * 391 * name can be one or several of the following notations, 392 * separated by '+' or '|': 393 * - the name of an usual channel layout (mono, stereo, 4.0, quad, 5.0, 394 * 5.0(side), 5.1, 5.1(side), 7.1, 7.1(wide), downmix); 395 * - the name of a single channel (FL, FR, FC, LFE, BL, BR, FLC, FRC, BC, 396 * SL, SR, TC, TFL, TFC, TFR, TBL, TBC, TBR, DL, DR); 397 * - a number of channels, in decimal, followed by 'c', yielding 398 * the default channel layout for that number of channels (@see 399 * av_get_default_channel_layout); 400 * - a channel layout mask, in hexadecimal starting with "0x" (see the 401 * AV_CH_* macros). 402 * 403 * Example: "stereo+FC" = "2c+FC" = "2c+1c" = "0x7" 404 * 405 * @deprecated use av_channel_layout_from_string() 406 */ 407 attribute_deprecated 408 uint64_t av_get_channel_layout(const char *name); 409 410 /** 411 * Return a channel layout and the number of channels based on the specified name. 412 * 413 * This function is similar to (@see av_get_channel_layout), but can also parse 414 * unknown channel layout specifications. 415 * 416 * @param[in] name channel layout specification string 417 * @param[out] channel_layout parsed channel layout (0 if unknown) 418 * @param[out] nb_channels number of channels 419 * 420 * @return 0 on success, AVERROR(EINVAL) if the parsing fails. 421 * @deprecated use av_channel_layout_from_string() 422 */ 423 attribute_deprecated 424 int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels); 425 426 /** 427 * Return a description of a channel layout. 428 * If nb_channels is <= 0, it is guessed from the channel_layout. 429 * 430 * @param buf put here the string containing the channel layout 431 * @param buf_size size in bytes of the buffer 432 * @deprecated use av_channel_layout_describe() 433 */ 434 attribute_deprecated 435 void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout); 436 437 /** 438 * Append a description of a channel layout to a bprint buffer. 439 * @deprecated use av_channel_layout_describe() 440 */ 441 attribute_deprecated 442 void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout); 443 444 /** 445 * Return the number of channels in the channel layout. 446 * @deprecated use AVChannelLayout.nb_channels 447 */ 448 attribute_deprecated 449 int av_get_channel_layout_nb_channels(uint64_t channel_layout); 450 451 /** 452 * Return default channel layout for a given number of channels. 453 * 454 * @deprecated use av_channel_layout_default() 455 */ 456 attribute_deprecated 457 int64_t av_get_default_channel_layout(int nb_channels); 458 459 /** 460 * Get the index of a channel in channel_layout. 461 * 462 * @param channel a channel layout describing exactly one channel which must be 463 * present in channel_layout. 464 * 465 * @return index of channel in channel_layout on success, a negative AVERROR 466 * on error. 467 * 468 * @deprecated use av_channel_layout_index_from_channel() 469 */ 470 attribute_deprecated 471 int av_get_channel_layout_channel_index(uint64_t channel_layout, 472 uint64_t channel); 473 474 /** 475 * Get the channel with the given index in channel_layout. 476 * @deprecated use av_channel_layout_channel_from_index() 477 */ 478 attribute_deprecated 479 uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index); 480 481 /** 482 * Get the name of a given channel. 483 * 484 * @return channel name on success, NULL on error. 485 * 486 * @deprecated use av_channel_name() 487 */ 488 attribute_deprecated 489 const char *av_get_channel_name(uint64_t channel); 490 491 /** 492 * Get the description of a given channel. 493 * 494 * @param channel a channel layout with a single channel 495 * @return channel description on success, NULL on error 496 * @deprecated use av_channel_description() 497 */ 498 attribute_deprecated 499 const char *av_get_channel_description(uint64_t channel); 500 501 /** 502 * Get the value and name of a standard channel layout. 503 * 504 * @param[in] index index in an internal list, starting at 0 505 * @param[out] layout channel layout mask 506 * @param[out] name name of the layout 507 * @return 0 if the layout exists, 508 * <0 if index is beyond the limits 509 * @deprecated use av_channel_layout_standard() 510 */ 511 attribute_deprecated 512 int av_get_standard_channel_layout(unsigned index, uint64_t *layout, 513 const char **name); 514 #endif 515 516 /** 517 * Get a human readable string in an abbreviated form describing a given channel. 518 * This is the inverse function of @ref av_channel_from_string(). 519 * 520 * @param buf pre-allocated buffer where to put the generated string 521 * @param buf_size size in bytes of the buffer. 522 * @return amount of bytes needed to hold the output string, or a negative AVERROR 523 * on failure. If the returned value is bigger than buf_size, then the 524 * string was truncated. 525 */ 526 int av_channel_name(char *buf, size_t buf_size, enum AVChannel channel); 527 528 /** 529 * bprint variant of av_channel_name(). 530 * 531 * @note the string will be appended to the bprint buffer. 532 */ 533 void av_channel_name_bprint(struct AVBPrint *bp, enum AVChannel channel_id); 534 535 /** 536 * Get a human readable string describing a given channel. 537 * 538 * @param buf pre-allocated buffer where to put the generated string 539 * @param buf_size size in bytes of the buffer. 540 * @return amount of bytes needed to hold the output string, or a negative AVERROR 541 * on failure. If the returned value is bigger than buf_size, then the 542 * string was truncated. 543 */ 544 int av_channel_description(char *buf, size_t buf_size, enum AVChannel channel); 545 546 /** 547 * bprint variant of av_channel_description(). 548 * 549 * @note the string will be appended to the bprint buffer. 550 */ 551 void av_channel_description_bprint(struct AVBPrint *bp, enum AVChannel channel_id); 552 553 /** 554 * This is the inverse function of @ref av_channel_name(). 555 * 556 * @return the channel with the given name 557 * AV_CHAN_NONE when name does not identify a known channel 558 */ 559 enum AVChannel av_channel_from_string(const char *name); 560 561 /** 562 * Initialize a native channel layout from a bitmask indicating which channels 563 * are present. 564 * 565 * @param channel_layout the layout structure to be initialized 566 * @param mask bitmask describing the channel layout 567 * 568 * @return 0 on success 569 * AVERROR(EINVAL) for invalid mask values 570 */ 571 int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask); 572 573 /** 574 * Initialize a channel layout from a given string description. 575 * The input string can be represented by: 576 * - the formal channel layout name (returned by av_channel_layout_describe()) 577 * - single or multiple channel names (returned by av_channel_name(), eg. "FL", 578 * or concatenated with "+", each optionally containing a custom name after 579 * a "@", eg. "FL@Left+FR@Right+LFE") 580 * - a decimal or hexadecimal value of a native channel layout (eg. "4" or "0x4") 581 * - the number of channels with default layout (eg. "4c") 582 * - the number of unordered channels (eg. "4C" or "4 channels") 583 * - the ambisonic order followed by optional non-diegetic channels (eg. 584 * "ambisonic 2+stereo") 585 * 586 * @param channel_layout input channel layout 587 * @param str string describing the channel layout 588 * @return 0 channel layout was detected, AVERROR_INVALIDATATA otherwise 589 */ 590 int av_channel_layout_from_string(AVChannelLayout *channel_layout, 591 const char *str); 592 593 /** 594 * Get the default channel layout for a given number of channels. 595 * 596 * @param channel_layout the layout structure to be initialized 597 * @param nb_channels number of channels 598 */ 599 void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels); 600 601 /** 602 * Iterate over all standard channel layouts. 603 * 604 * @param opaque a pointer where libavutil will store the iteration state. Must 605 * point to NULL to start the iteration. 606 * 607 * @return the standard channel layout or NULL when the iteration is 608 * finished 609 */ 610 const AVChannelLayout *av_channel_layout_standard(void **opaque); 611 612 /** 613 * Free any allocated data in the channel layout and reset the channel 614 * count to 0. 615 * 616 * @param channel_layout the layout structure to be uninitialized 617 */ 618 void av_channel_layout_uninit(AVChannelLayout *channel_layout); 619 620 /** 621 * Make a copy of a channel layout. This differs from just assigning src to dst 622 * in that it allocates and copies the map for AV_CHANNEL_ORDER_CUSTOM. 623 * 624 * @note the destination channel_layout will be always uninitialized before copy. 625 * 626 * @param dst destination channel layout 627 * @param src source channel layout 628 * @return 0 on success, a negative AVERROR on error. 629 */ 630 int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src); 631 632 /** 633 * Get a human-readable string describing the channel layout properties. 634 * The string will be in the same format that is accepted by 635 * @ref av_channel_layout_from_string(), allowing to rebuild the same 636 * channel layout, except for opaque pointers. 637 * 638 * @param channel_layout channel layout to be described 639 * @param buf pre-allocated buffer where to put the generated string 640 * @param buf_size size in bytes of the buffer. 641 * @return amount of bytes needed to hold the output string, or a negative AVERROR 642 * on failure. If the returned value is bigger than buf_size, then the 643 * string was truncated. 644 */ 645 int av_channel_layout_describe(const AVChannelLayout *channel_layout, 646 char *buf, size_t buf_size); 647 648 /** 649 * bprint variant of av_channel_layout_describe(). 650 * 651 * @note the string will be appended to the bprint buffer. 652 * @return 0 on success, or a negative AVERROR value on failure. 653 */ 654 int av_channel_layout_describe_bprint(const AVChannelLayout *channel_layout, 655 struct AVBPrint *bp); 656 657 /** 658 * Get the channel with the given index in a channel layout. 659 * 660 * @param channel_layout input channel layout 661 * @return channel with the index idx in channel_layout on success or 662 * AV_CHAN_NONE on failure (if idx is not valid or the channel order is 663 * unspecified) 664 */ 665 enum AVChannel 666 av_channel_layout_channel_from_index(const AVChannelLayout *channel_layout, unsigned int idx); 667 668 /** 669 * Get the index of a given channel in a channel layout. In case multiple 670 * channels are found, only the first match will be returned. 671 * 672 * @param channel_layout input channel layout 673 * @return index of channel in channel_layout on success or a negative number if 674 * channel is not present in channel_layout. 675 */ 676 int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout, 677 enum AVChannel channel); 678 679 /** 680 * Get the index in a channel layout of a channel described by the given string. 681 * In case multiple channels are found, only the first match will be returned. 682 * 683 * This function accepts channel names in the same format as 684 * @ref av_channel_from_string(). 685 * 686 * @param channel_layout input channel layout 687 * @return a channel index described by the given string, or a negative AVERROR 688 * value. 689 */ 690 int av_channel_layout_index_from_string(const AVChannelLayout *channel_layout, 691 const char *name); 692 693 /** 694 * Get a channel described by the given string. 695 * 696 * This function accepts channel names in the same format as 697 * @ref av_channel_from_string(). 698 * 699 * @param channel_layout input channel layout 700 * @return a channel described by the given string in channel_layout on success 701 * or AV_CHAN_NONE on failure (if the string is not valid or the channel 702 * order is unspecified) 703 */ 704 enum AVChannel 705 av_channel_layout_channel_from_string(const AVChannelLayout *channel_layout, 706 const char *name); 707 708 /** 709 * Find out what channels from a given set are present in a channel layout, 710 * without regard for their positions. 711 * 712 * @param channel_layout input channel layout 713 * @param mask a combination of AV_CH_* representing a set of channels 714 * @return a bitfield representing all the channels from mask that are present 715 * in channel_layout 716 */ 717 uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout, 718 uint64_t mask); 719 720 /** 721 * Check whether a channel layout is valid, i.e. can possibly describe audio 722 * data. 723 * 724 * @param channel_layout input channel layout 725 * @return 1 if channel_layout is valid, 0 otherwise. 726 */ 727 int av_channel_layout_check(const AVChannelLayout *channel_layout); 728 729 /** 730 * Check whether two channel layouts are semantically the same, i.e. the same 731 * channels are present on the same positions in both. 732 * 733 * If one of the channel layouts is AV_CHANNEL_ORDER_UNSPEC, while the other is 734 * not, they are considered to be unequal. If both are AV_CHANNEL_ORDER_UNSPEC, 735 * they are considered equal iff the channel counts are the same in both. 736 * 737 * @param chl input channel layout 738 * @param chl1 input channel layout 739 * @return 0 if chl and chl1 are equal, 1 if they are not equal. A negative 740 * AVERROR code if one or both are invalid. 741 */ 742 int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1); 743 744 /** 745 * @} 746 * @} 747 */ 748 749 #endif /* AVUTIL_CHANNEL_LAYOUT_H */ 750