1 /* Copyright (c) 2017 Google Inc. 2 Written by Andrew Allen */ 3 /* 4 Redistribution and use in source and binary forms, with or without 5 modification, are permitted provided that the following conditions 6 are met: 7 8 - Redistributions of source code must retain the above copyright 9 notice, this list of conditions and the following disclaimer. 10 11 - Redistributions in binary form must reproduce the above copyright 12 notice, this list of conditions and the following disclaimer in the 13 documentation and/or other materials provided with the distribution. 14 15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 19 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 22 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 23 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 24 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 25 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 /** 29 * @file opus_projection.h 30 * @brief Opus projection reference API 31 */ 32 33 #ifndef OPUS_PROJECTION_H 34 #define OPUS_PROJECTION_H 35 36 #include "opus_multistream.h" 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /** @cond OPUS_INTERNAL_DOC */ 43 44 /** These are the actual encoder and decoder CTL ID numbers. 45 * They should not be used directly by applications.c 46 * In general, SETs should be even and GETs should be odd.*/ 47 /**@{*/ 48 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX_GAIN_REQUEST 6001 49 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX_SIZE_REQUEST 6003 50 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX_REQUEST 6005 51 /**@}*/ 52 53 54 /** @endcond */ 55 56 /** @defgroup opus_projection_ctls Projection specific encoder and decoder CTLs 57 * 58 * These are convenience macros that are specific to the 59 * opus_projection_encoder_ctl() and opus_projection_decoder_ctl() 60 * interface. 61 * The CTLs from @ref opus_genericctls, @ref opus_encoderctls, 62 * @ref opus_decoderctls, and @ref opus_multistream_ctls may be applied to a 63 * projection encoder or decoder as well. 64 */ 65 /**@{*/ 66 67 /** Gets the gain (in dB. S7.8-format) of the demixing matrix from the encoder. 68 * @param[out] x <tt>opus_int32 *</tt>: Returns the gain (in dB. S7.8-format) 69 * of the demixing matrix. 70 * @hideinitializer 71 */ 72 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX_GAIN(x) OPUS_PROJECTION_GET_DEMIXING_MATRIX_GAIN_REQUEST, __opus_check_int_ptr(x) 73 74 75 /** Gets the size in bytes of the demixing matrix from the encoder. 76 * @param[out] x <tt>opus_int32 *</tt>: Returns the size in bytes of the 77 * demixing matrix. 78 * @hideinitializer 79 */ 80 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX_SIZE(x) OPUS_PROJECTION_GET_DEMIXING_MATRIX_SIZE_REQUEST, __opus_check_int_ptr(x) 81 82 83 /** Copies the demixing matrix to the supplied pointer location. 84 * @param[out] x <tt>unsigned char *</tt>: Returns the demixing matrix to the 85 * supplied pointer location. 86 * @param y <tt>opus_int32</tt>: The size in bytes of the reserved memory at the 87 * pointer location. 88 * @hideinitializer 89 */ 90 #define OPUS_PROJECTION_GET_DEMIXING_MATRIX(x,y) OPUS_PROJECTION_GET_DEMIXING_MATRIX_REQUEST, x, __opus_check_int(y) 91 92 93 /**@}*/ 94 95 /** Opus projection encoder state. 96 * This contains the complete state of a projection Opus encoder. 97 * It is position independent and can be freely copied. 98 * @see opus_projection_ambisonics_encoder_create 99 */ 100 typedef struct OpusProjectionEncoder OpusProjectionEncoder; 101 102 103 /** Opus projection decoder state. 104 * This contains the complete state of a projection Opus decoder. 105 * It is position independent and can be freely copied. 106 * @see opus_projection_decoder_create 107 * @see opus_projection_decoder_init 108 */ 109 typedef struct OpusProjectionDecoder OpusProjectionDecoder; 110 111 112 /**\name Projection encoder functions */ 113 /**@{*/ 114 115 /** Gets the size of an OpusProjectionEncoder structure. 116 * @param channels <tt>int</tt>: The total number of input channels to encode. 117 * This must be no more than 255. 118 * @param mapping_family <tt>int</tt>: The mapping family to use for selecting 119 * the appropriate projection. 120 * @returns The size in bytes on success, or a negative error code 121 * (see @ref opus_errorcodes) on error. 122 */ 123 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT opus_int32 opus_projection_ambisonics_encoder_get_size( 124 int channels, 125 int mapping_family 126 ); 127 128 129 /** Allocates and initializes a projection encoder state. 130 * Call opus_projection_encoder_destroy() to release 131 * this object when finished. 132 * @param Fs <tt>opus_int32</tt>: Sampling rate of the input signal (in Hz). 133 * This must be one of 8000, 12000, 16000, 134 * 24000, or 48000. 135 * @param channels <tt>int</tt>: Number of channels in the input signal. 136 * This must be at most 255. 137 * It may be greater than the number of 138 * coded channels (<code>streams + 139 * coupled_streams</code>). 140 * @param mapping_family <tt>int</tt>: The mapping family to use for selecting 141 * the appropriate projection. 142 * @param[out] streams <tt>int *</tt>: The total number of streams that will 143 * be encoded from the input. 144 * @param[out] coupled_streams <tt>int *</tt>: Number of coupled (2 channel) 145 * streams that will be encoded from the input. 146 * @param application <tt>int</tt>: The target encoder application. 147 * This must be one of the following: 148 * <dl> 149 * <dt>#OPUS_APPLICATION_VOIP</dt> 150 * <dd>Process signal for improved speech intelligibility.</dd> 151 * <dt>#OPUS_APPLICATION_AUDIO</dt> 152 * <dd>Favor faithfulness to the original input.</dd> 153 * <dt>#OPUS_APPLICATION_RESTRICTED_LOWDELAY</dt> 154 * <dd>Configure the minimum possible coding delay by disabling certain modes 155 * of operation.</dd> 156 * </dl> 157 * @param[out] error <tt>int *</tt>: Returns #OPUS_OK on success, or an error 158 * code (see @ref opus_errorcodes) on 159 * failure. 160 */ 161 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT OpusProjectionEncoder *opus_projection_ambisonics_encoder_create( 162 opus_int32 Fs, 163 int channels, 164 int mapping_family, 165 int *streams, 166 int *coupled_streams, 167 int application, 168 int *error 169 ) OPUS_ARG_NONNULL(4) OPUS_ARG_NONNULL(5); 170 171 172 /** Initialize a previously allocated projection encoder state. 173 * The memory pointed to by \a st must be at least the size returned by 174 * opus_projection_ambisonics_encoder_get_size(). 175 * This is intended for applications which use their own allocator instead of 176 * malloc. 177 * To reset a previously initialized state, use the #OPUS_RESET_STATE CTL. 178 * @see opus_projection_ambisonics_encoder_create 179 * @see opus_projection_ambisonics_encoder_get_size 180 * @param st <tt>OpusProjectionEncoder*</tt>: Projection encoder state to initialize. 181 * @param Fs <tt>opus_int32</tt>: Sampling rate of the input signal (in Hz). 182 * This must be one of 8000, 12000, 16000, 183 * 24000, or 48000. 184 * @param channels <tt>int</tt>: Number of channels in the input signal. 185 * This must be at most 255. 186 * It may be greater than the number of 187 * coded channels (<code>streams + 188 * coupled_streams</code>). 189 * @param streams <tt>int</tt>: The total number of streams to encode from the 190 * input. 191 * This must be no more than the number of channels. 192 * @param coupled_streams <tt>int</tt>: Number of coupled (2 channel) streams 193 * to encode. 194 * This must be no larger than the total 195 * number of streams. 196 * Additionally, The total number of 197 * encoded channels (<code>streams + 198 * coupled_streams</code>) must be no 199 * more than the number of input channels. 200 * @param application <tt>int</tt>: The target encoder application. 201 * This must be one of the following: 202 * <dl> 203 * <dt>#OPUS_APPLICATION_VOIP</dt> 204 * <dd>Process signal for improved speech intelligibility.</dd> 205 * <dt>#OPUS_APPLICATION_AUDIO</dt> 206 * <dd>Favor faithfulness to the original input.</dd> 207 * <dt>#OPUS_APPLICATION_RESTRICTED_LOWDELAY</dt> 208 * <dd>Configure the minimum possible coding delay by disabling certain modes 209 * of operation.</dd> 210 * </dl> 211 * @returns #OPUS_OK on success, or an error code (see @ref opus_errorcodes) 212 * on failure. 213 */ 214 OPUS_EXPORT int opus_projection_ambisonics_encoder_init( 215 OpusProjectionEncoder *st, 216 opus_int32 Fs, 217 int channels, 218 int mapping_family, 219 int *streams, 220 int *coupled_streams, 221 int application 222 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(5) OPUS_ARG_NONNULL(6); 223 224 225 /** Encodes a projection Opus frame. 226 * @param st <tt>OpusProjectionEncoder*</tt>: Projection encoder state. 227 * @param[in] pcm <tt>const opus_int16*</tt>: The input signal as interleaved 228 * samples. 229 * This must contain 230 * <code>frame_size*channels</code> 231 * samples. 232 * @param frame_size <tt>int</tt>: Number of samples per channel in the input 233 * signal. 234 * This must be an Opus frame size for the 235 * encoder's sampling rate. 236 * For example, at 48 kHz the permitted values 237 * are 120, 240, 480, 960, 1920, and 2880. 238 * Passing in a duration of less than 10 ms 239 * (480 samples at 48 kHz) will prevent the 240 * encoder from using the LPC or hybrid modes. 241 * @param[out] data <tt>unsigned char*</tt>: Output payload. 242 * This must contain storage for at 243 * least \a max_data_bytes. 244 * @param [in] max_data_bytes <tt>opus_int32</tt>: Size of the allocated 245 * memory for the output 246 * payload. This may be 247 * used to impose an upper limit on 248 * the instant bitrate, but should 249 * not be used as the only bitrate 250 * control. Use #OPUS_SET_BITRATE to 251 * control the bitrate. 252 * @returns The length of the encoded packet (in bytes) on success or a 253 * negative error code (see @ref opus_errorcodes) on failure. 254 */ 255 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT int opus_projection_encode( 256 OpusProjectionEncoder *st, 257 const opus_int16 *pcm, 258 int frame_size, 259 unsigned char *data, 260 opus_int32 max_data_bytes 261 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(2) OPUS_ARG_NONNULL(4); 262 263 264 /** Encodes a projection Opus frame from floating point input. 265 * @param st <tt>OpusProjectionEncoder*</tt>: Projection encoder state. 266 * @param[in] pcm <tt>const float*</tt>: The input signal as interleaved 267 * samples with a normal range of 268 * +/-1.0. 269 * Samples with a range beyond +/-1.0 270 * are supported but will be clipped by 271 * decoders using the integer API and 272 * should only be used if it is known 273 * that the far end supports extended 274 * dynamic range. 275 * This must contain 276 * <code>frame_size*channels</code> 277 * samples. 278 * @param frame_size <tt>int</tt>: Number of samples per channel in the input 279 * signal. 280 * This must be an Opus frame size for the 281 * encoder's sampling rate. 282 * For example, at 48 kHz the permitted values 283 * are 120, 240, 480, 960, 1920, and 2880. 284 * Passing in a duration of less than 10 ms 285 * (480 samples at 48 kHz) will prevent the 286 * encoder from using the LPC or hybrid modes. 287 * @param[out] data <tt>unsigned char*</tt>: Output payload. 288 * This must contain storage for at 289 * least \a max_data_bytes. 290 * @param [in] max_data_bytes <tt>opus_int32</tt>: Size of the allocated 291 * memory for the output 292 * payload. This may be 293 * used to impose an upper limit on 294 * the instant bitrate, but should 295 * not be used as the only bitrate 296 * control. Use #OPUS_SET_BITRATE to 297 * control the bitrate. 298 * @returns The length of the encoded packet (in bytes) on success or a 299 * negative error code (see @ref opus_errorcodes) on failure. 300 */ 301 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT int opus_projection_encode_float( 302 OpusProjectionEncoder *st, 303 const float *pcm, 304 int frame_size, 305 unsigned char *data, 306 opus_int32 max_data_bytes 307 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(2) OPUS_ARG_NONNULL(4); 308 309 310 /** Frees an <code>OpusProjectionEncoder</code> allocated by 311 * opus_projection_ambisonics_encoder_create(). 312 * @param st <tt>OpusProjectionEncoder*</tt>: Projection encoder state to be freed. 313 */ 314 OPUS_EXPORT void opus_projection_encoder_destroy(OpusProjectionEncoder *st); 315 316 317 /** Perform a CTL function on a projection Opus encoder. 318 * 319 * Generally the request and subsequent arguments are generated by a 320 * convenience macro. 321 * @param st <tt>OpusProjectionEncoder*</tt>: Projection encoder state. 322 * @param request This and all remaining parameters should be replaced by one 323 * of the convenience macros in @ref opus_genericctls, 324 * @ref opus_encoderctls, @ref opus_multistream_ctls, or 325 * @ref opus_projection_ctls 326 * @see opus_genericctls 327 * @see opus_encoderctls 328 * @see opus_multistream_ctls 329 * @see opus_projection_ctls 330 */ 331 OPUS_EXPORT int opus_projection_encoder_ctl(OpusProjectionEncoder *st, int request, ...) OPUS_ARG_NONNULL(1); 332 333 334 /**@}*/ 335 336 /**\name Projection decoder functions */ 337 /**@{*/ 338 339 /** Gets the size of an <code>OpusProjectionDecoder</code> structure. 340 * @param channels <tt>int</tt>: The total number of output channels. 341 * This must be no more than 255. 342 * @param streams <tt>int</tt>: The total number of streams coded in the 343 * input. 344 * This must be no more than 255. 345 * @param coupled_streams <tt>int</tt>: Number streams to decode as coupled 346 * (2 channel) streams. 347 * This must be no larger than the total 348 * number of streams. 349 * Additionally, The total number of 350 * coded channels (<code>streams + 351 * coupled_streams</code>) must be no 352 * more than 255. 353 * @returns The size in bytes on success, or a negative error code 354 * (see @ref opus_errorcodes) on error. 355 */ 356 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT opus_int32 opus_projection_decoder_get_size( 357 int channels, 358 int streams, 359 int coupled_streams 360 ); 361 362 363 /** Allocates and initializes a projection decoder state. 364 * Call opus_projection_decoder_destroy() to release 365 * this object when finished. 366 * @param Fs <tt>opus_int32</tt>: Sampling rate to decode at (in Hz). 367 * This must be one of 8000, 12000, 16000, 368 * 24000, or 48000. 369 * @param channels <tt>int</tt>: Number of channels to output. 370 * This must be at most 255. 371 * It may be different from the number of coded 372 * channels (<code>streams + 373 * coupled_streams</code>). 374 * @param streams <tt>int</tt>: The total number of streams coded in the 375 * input. 376 * This must be no more than 255. 377 * @param coupled_streams <tt>int</tt>: Number of streams to decode as coupled 378 * (2 channel) streams. 379 * This must be no larger than the total 380 * number of streams. 381 * Additionally, The total number of 382 * coded channels (<code>streams + 383 * coupled_streams</code>) must be no 384 * more than 255. 385 * @param[in] demixing_matrix <tt>const unsigned char[demixing_matrix_size]</tt>: Demixing matrix 386 * that mapping from coded channels to output channels, 387 * as described in @ref opus_projection and 388 * @ref opus_projection_ctls. 389 * @param demixing_matrix_size <tt>opus_int32</tt>: The size in bytes of the 390 * demixing matrix, as 391 * described in @ref 392 * opus_projection_ctls. 393 * @param[out] error <tt>int *</tt>: Returns #OPUS_OK on success, or an error 394 * code (see @ref opus_errorcodes) on 395 * failure. 396 */ 397 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT OpusProjectionDecoder *opus_projection_decoder_create( 398 opus_int32 Fs, 399 int channels, 400 int streams, 401 int coupled_streams, 402 unsigned char *demixing_matrix, 403 opus_int32 demixing_matrix_size, 404 int *error 405 ) OPUS_ARG_NONNULL(5); 406 407 408 /** Intialize a previously allocated projection decoder state object. 409 * The memory pointed to by \a st must be at least the size returned by 410 * opus_projection_decoder_get_size(). 411 * This is intended for applications which use their own allocator instead of 412 * malloc. 413 * To reset a previously initialized state, use the #OPUS_RESET_STATE CTL. 414 * @see opus_projection_decoder_create 415 * @see opus_projection_deocder_get_size 416 * @param st <tt>OpusProjectionDecoder*</tt>: Projection encoder state to initialize. 417 * @param Fs <tt>opus_int32</tt>: Sampling rate to decode at (in Hz). 418 * This must be one of 8000, 12000, 16000, 419 * 24000, or 48000. 420 * @param channels <tt>int</tt>: Number of channels to output. 421 * This must be at most 255. 422 * It may be different from the number of coded 423 * channels (<code>streams + 424 * coupled_streams</code>). 425 * @param streams <tt>int</tt>: The total number of streams coded in the 426 * input. 427 * This must be no more than 255. 428 * @param coupled_streams <tt>int</tt>: Number of streams to decode as coupled 429 * (2 channel) streams. 430 * This must be no larger than the total 431 * number of streams. 432 * Additionally, The total number of 433 * coded channels (<code>streams + 434 * coupled_streams</code>) must be no 435 * more than 255. 436 * @param[in] demixing_matrix <tt>const unsigned char[demixing_matrix_size]</tt>: Demixing matrix 437 * that mapping from coded channels to output channels, 438 * as described in @ref opus_projection and 439 * @ref opus_projection_ctls. 440 * @param demixing_matrix_size <tt>opus_int32</tt>: The size in bytes of the 441 * demixing matrix, as 442 * described in @ref 443 * opus_projection_ctls. 444 * @returns #OPUS_OK on success, or an error code (see @ref opus_errorcodes) 445 * on failure. 446 */ 447 OPUS_EXPORT int opus_projection_decoder_init( 448 OpusProjectionDecoder *st, 449 opus_int32 Fs, 450 int channels, 451 int streams, 452 int coupled_streams, 453 unsigned char *demixing_matrix, 454 opus_int32 demixing_matrix_size 455 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(6); 456 457 458 /** Decode a projection Opus packet. 459 * @param st <tt>OpusProjectionDecoder*</tt>: Projection decoder state. 460 * @param[in] data <tt>const unsigned char*</tt>: Input payload. 461 * Use a <code>NULL</code> 462 * pointer to indicate packet 463 * loss. 464 * @param len <tt>opus_int32</tt>: Number of bytes in payload. 465 * @param[out] pcm <tt>opus_int16*</tt>: Output signal, with interleaved 466 * samples. 467 * This must contain room for 468 * <code>frame_size*channels</code> 469 * samples. 470 * @param frame_size <tt>int</tt>: The number of samples per channel of 471 * available space in \a pcm. 472 * If this is less than the maximum packet duration 473 * (120 ms; 5760 for 48kHz), this function will not be capable 474 * of decoding some packets. In the case of PLC (data==NULL) 475 * or FEC (decode_fec=1), then frame_size needs to be exactly 476 * the duration of audio that is missing, otherwise the 477 * decoder will not be in the optimal state to decode the 478 * next incoming packet. For the PLC and FEC cases, frame_size 479 * <b>must</b> be a multiple of 2.5 ms. 480 * @param decode_fec <tt>int</tt>: Flag (0 or 1) to request that any in-band 481 * forward error correction data be decoded. 482 * If no such data is available, the frame is 483 * decoded as if it were lost. 484 * @returns Number of samples decoded on success or a negative error code 485 * (see @ref opus_errorcodes) on failure. 486 */ 487 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT int opus_projection_decode( 488 OpusProjectionDecoder *st, 489 const unsigned char *data, 490 opus_int32 len, 491 opus_int16 *pcm, 492 int frame_size, 493 int decode_fec 494 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(4); 495 496 497 /** Decode a projection Opus packet with floating point output. 498 * @param st <tt>OpusProjectionDecoder*</tt>: Projection decoder state. 499 * @param[in] data <tt>const unsigned char*</tt>: Input payload. 500 * Use a <code>NULL</code> 501 * pointer to indicate packet 502 * loss. 503 * @param len <tt>opus_int32</tt>: Number of bytes in payload. 504 * @param[out] pcm <tt>opus_int16*</tt>: Output signal, with interleaved 505 * samples. 506 * This must contain room for 507 * <code>frame_size*channels</code> 508 * samples. 509 * @param frame_size <tt>int</tt>: The number of samples per channel of 510 * available space in \a pcm. 511 * If this is less than the maximum packet duration 512 * (120 ms; 5760 for 48kHz), this function will not be capable 513 * of decoding some packets. In the case of PLC (data==NULL) 514 * or FEC (decode_fec=1), then frame_size needs to be exactly 515 * the duration of audio that is missing, otherwise the 516 * decoder will not be in the optimal state to decode the 517 * next incoming packet. For the PLC and FEC cases, frame_size 518 * <b>must</b> be a multiple of 2.5 ms. 519 * @param decode_fec <tt>int</tt>: Flag (0 or 1) to request that any in-band 520 * forward error correction data be decoded. 521 * If no such data is available, the frame is 522 * decoded as if it were lost. 523 * @returns Number of samples decoded on success or a negative error code 524 * (see @ref opus_errorcodes) on failure. 525 */ 526 OPUS_EXPORT OPUS_WARN_UNUSED_RESULT int opus_projection_decode_float( 527 OpusProjectionDecoder *st, 528 const unsigned char *data, 529 opus_int32 len, 530 float *pcm, 531 int frame_size, 532 int decode_fec 533 ) OPUS_ARG_NONNULL(1) OPUS_ARG_NONNULL(4); 534 535 536 /** Perform a CTL function on a projection Opus decoder. 537 * 538 * Generally the request and subsequent arguments are generated by a 539 * convenience macro. 540 * @param st <tt>OpusProjectionDecoder*</tt>: Projection decoder state. 541 * @param request This and all remaining parameters should be replaced by one 542 * of the convenience macros in @ref opus_genericctls, 543 * @ref opus_decoderctls, @ref opus_multistream_ctls, or 544 * @ref opus_projection_ctls. 545 * @see opus_genericctls 546 * @see opus_decoderctls 547 * @see opus_multistream_ctls 548 * @see opus_projection_ctls 549 */ 550 OPUS_EXPORT int opus_projection_decoder_ctl(OpusProjectionDecoder *st, int request, ...) OPUS_ARG_NONNULL(1); 551 552 553 /** Frees an <code>OpusProjectionDecoder</code> allocated by 554 * opus_projection_decoder_create(). 555 * @param st <tt>OpusProjectionDecoder</tt>: Projection decoder state to be freed. 556 */ 557 OPUS_EXPORT void opus_projection_decoder_destroy(OpusProjectionDecoder *st); 558 559 560 /**@}*/ 561 562 /**@}*/ 563 564 #ifdef __cplusplus 565 } 566 #endif 567 568 #endif /* OPUS_PROJECTION_H */ 569