1 /* libFLAC - Free Lossless Audio Codec library 2 * Copyright (C) 2000-2009 Josh Coalson 3 * Copyright (C) 2011-2014 Xiph.Org Foundation 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * - Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 12 * - Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * - Neither the name of the Xiph.org Foundation nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR 24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #ifndef FLAC__STREAM_DECODER_H 34 #define FLAC__STREAM_DECODER_H 35 36 #include <stdio.h> /* for FILE */ 37 #include "export.h" 38 #include "format.h" 39 40 #ifdef __cplusplus 41 extern "C" { 42 #endif 43 44 45 /** \file include/FLAC/stream_decoder.h 46 * 47 * \brief 48 * This module contains the functions which implement the stream 49 * decoder. 50 * 51 * See the detailed documentation in the 52 * \link flac_stream_decoder stream decoder \endlink module. 53 */ 54 55 /** \defgroup flac_decoder FLAC/ \*_decoder.h: decoder interfaces 56 * \ingroup flac 57 * 58 * \brief 59 * This module describes the decoder layers provided by libFLAC. 60 * 61 * The stream decoder can be used to decode complete streams either from 62 * the client via callbacks, or directly from a file, depending on how 63 * it is initialized. When decoding via callbacks, the client provides 64 * callbacks for reading FLAC data and writing decoded samples, and 65 * handling metadata and errors. If the client also supplies seek-related 66 * callback, the decoder function for sample-accurate seeking within the 67 * FLAC input is also available. When decoding from a file, the client 68 * needs only supply a filename or open \c FILE* and write/metadata/error 69 * callbacks; the rest of the callbacks are supplied internally. For more 70 * info see the \link flac_stream_decoder stream decoder \endlink module. 71 */ 72 73 /** \defgroup flac_stream_decoder FLAC/stream_decoder.h: stream decoder interface 74 * \ingroup flac_decoder 75 * 76 * \brief 77 * This module contains the functions which implement the stream 78 * decoder. 79 * 80 * The stream decoder can decode native FLAC, and optionally Ogg FLAC 81 * (check FLAC_API_SUPPORTS_OGG_FLAC) streams and files. 82 * 83 * The basic usage of this decoder is as follows: 84 * - The program creates an instance of a decoder using 85 * FLAC__stream_decoder_new(). 86 * - The program overrides the default settings using 87 * FLAC__stream_decoder_set_*() functions. 88 * - The program initializes the instance to validate the settings and 89 * prepare for decoding using 90 * - FLAC__stream_decoder_init_stream() or FLAC__stream_decoder_init_FILE() 91 * or FLAC__stream_decoder_init_file() for native FLAC, 92 * - FLAC__stream_decoder_init_ogg_stream() or FLAC__stream_decoder_init_ogg_FILE() 93 * or FLAC__stream_decoder_init_ogg_file() for Ogg FLAC 94 * - The program calls the FLAC__stream_decoder_process_*() functions 95 * to decode data, which subsequently calls the callbacks. 96 * - The program finishes the decoding with FLAC__stream_decoder_finish(), 97 * which flushes the input and output and resets the decoder to the 98 * uninitialized state. 99 * - The instance may be used again or deleted with 100 * FLAC__stream_decoder_delete(). 101 * 102 * In more detail, the program will create a new instance by calling 103 * FLAC__stream_decoder_new(), then call FLAC__stream_decoder_set_*() 104 * functions to override the default decoder options, and call 105 * one of the FLAC__stream_decoder_init_*() functions. 106 * 107 * There are three initialization functions for native FLAC, one for 108 * setting up the decoder to decode FLAC data from the client via 109 * callbacks, and two for decoding directly from a FLAC file. 110 * 111 * For decoding via callbacks, use FLAC__stream_decoder_init_stream(). 112 * You must also supply several callbacks for handling I/O. Some (like 113 * seeking) are optional, depending on the capabilities of the input. 114 * 115 * For decoding directly from a file, use FLAC__stream_decoder_init_FILE() 116 * or FLAC__stream_decoder_init_file(). Then you must only supply an open 117 * \c FILE* or filename and fewer callbacks; the decoder will handle 118 * the other callbacks internally. 119 * 120 * There are three similarly-named init functions for decoding from Ogg 121 * FLAC streams. Check \c FLAC_API_SUPPORTS_OGG_FLAC to find out if the 122 * library has been built with Ogg support. 123 * 124 * Once the decoder is initialized, your program will call one of several 125 * functions to start the decoding process: 126 * 127 * - FLAC__stream_decoder_process_single() - Tells the decoder to process at 128 * most one metadata block or audio frame and return, calling either the 129 * metadata callback or write callback, respectively, once. If the decoder 130 * loses sync it will return with only the error callback being called. 131 * - FLAC__stream_decoder_process_until_end_of_metadata() - Tells the decoder 132 * to process the stream from the current location and stop upon reaching 133 * the first audio frame. The client will get one metadata, write, or error 134 * callback per metadata block, audio frame, or sync error, respectively. 135 * - FLAC__stream_decoder_process_until_end_of_stream() - Tells the decoder 136 * to process the stream from the current location until the read callback 137 * returns FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM or 138 * FLAC__STREAM_DECODER_READ_STATUS_ABORT. The client will get one metadata, 139 * write, or error callback per metadata block, audio frame, or sync error, 140 * respectively. 141 * 142 * When the decoder has finished decoding (normally or through an abort), 143 * the instance is finished by calling FLAC__stream_decoder_finish(), which 144 * ensures the decoder is in the correct state and frees memory. Then the 145 * instance may be deleted with FLAC__stream_decoder_delete() or initialized 146 * again to decode another stream. 147 * 148 * Seeking is exposed through the FLAC__stream_decoder_seek_absolute() method. 149 * At any point after the stream decoder has been initialized, the client can 150 * call this function to seek to an exact sample within the stream. 151 * Subsequently, the first time the write callback is called it will be 152 * passed a (possibly partial) block starting at that sample. 153 * 154 * If the client cannot seek via the callback interface provided, but still 155 * has another way of seeking, it can flush the decoder using 156 * FLAC__stream_decoder_flush() and start feeding data from the new position 157 * through the read callback. 158 * 159 * The stream decoder also provides MD5 signature checking. If this is 160 * turned on before initialization, FLAC__stream_decoder_finish() will 161 * report when the decoded MD5 signature does not match the one stored 162 * in the STREAMINFO block. MD5 checking is automatically turned off 163 * (until the next FLAC__stream_decoder_reset()) if there is no signature 164 * in the STREAMINFO block or when a seek is attempted. 165 * 166 * The FLAC__stream_decoder_set_metadata_*() functions deserve special 167 * attention. By default, the decoder only calls the metadata_callback for 168 * the STREAMINFO block. These functions allow you to tell the decoder 169 * explicitly which blocks to parse and return via the metadata_callback 170 * and/or which to skip. Use a FLAC__stream_decoder_set_metadata_respond_all(), 171 * FLAC__stream_decoder_set_metadata_ignore() ... or FLAC__stream_decoder_set_metadata_ignore_all(), 172 * FLAC__stream_decoder_set_metadata_respond() ... sequence to exactly specify 173 * which blocks to return. Remember that metadata blocks can potentially 174 * be big (for example, cover art) so filtering out the ones you don't 175 * use can reduce the memory requirements of the decoder. Also note the 176 * special forms FLAC__stream_decoder_set_metadata_respond_application(id) 177 * and FLAC__stream_decoder_set_metadata_ignore_application(id) for 178 * filtering APPLICATION blocks based on the application ID. 179 * 180 * STREAMINFO and SEEKTABLE blocks are always parsed and used internally, but 181 * they still can legally be filtered from the metadata_callback. 182 * 183 * \note 184 * The "set" functions may only be called when the decoder is in the 185 * state FLAC__STREAM_DECODER_UNINITIALIZED, i.e. after 186 * FLAC__stream_decoder_new() or FLAC__stream_decoder_finish(), but 187 * before FLAC__stream_decoder_init_*(). If this is the case they will 188 * return \c true, otherwise \c false. 189 * 190 * \note 191 * FLAC__stream_decoder_finish() resets all settings to the constructor 192 * defaults, including the callbacks. 193 * 194 * \{ 195 */ 196 197 198 /** State values for a FLAC__StreamDecoder 199 * 200 * The decoder's state can be obtained by calling FLAC__stream_decoder_get_state(). 201 */ 202 typedef enum { 203 204 FLAC__STREAM_DECODER_SEARCH_FOR_METADATA = 0, 205 /**< The decoder is ready to search for metadata. */ 206 207 FLAC__STREAM_DECODER_READ_METADATA, 208 /**< The decoder is ready to or is in the process of reading metadata. */ 209 210 FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC, 211 /**< The decoder is ready to or is in the process of searching for the 212 * frame sync code. 213 */ 214 215 FLAC__STREAM_DECODER_READ_FRAME, 216 /**< The decoder is ready to or is in the process of reading a frame. */ 217 218 FLAC__STREAM_DECODER_END_OF_STREAM, 219 /**< The decoder has reached the end of the stream. */ 220 221 FLAC__STREAM_DECODER_OGG_ERROR, 222 /**< An error occurred in the underlying Ogg layer. */ 223 224 FLAC__STREAM_DECODER_SEEK_ERROR, 225 /**< An error occurred while seeking. The decoder must be flushed 226 * with FLAC__stream_decoder_flush() or reset with 227 * FLAC__stream_decoder_reset() before decoding can continue. 228 */ 229 230 FLAC__STREAM_DECODER_ABORTED, 231 /**< The decoder was aborted by the read callback. */ 232 233 FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR, 234 /**< An error occurred allocating memory. The decoder is in an invalid 235 * state and can no longer be used. 236 */ 237 238 FLAC__STREAM_DECODER_UNINITIALIZED 239 /**< The decoder is in the uninitialized state; one of the 240 * FLAC__stream_decoder_init_*() functions must be called before samples 241 * can be processed. 242 */ 243 244 } FLAC__StreamDecoderState; 245 246 /** Maps a FLAC__StreamDecoderState to a C string. 247 * 248 * Using a FLAC__StreamDecoderState as the index to this array 249 * will give the string equivalent. The contents should not be modified. 250 */ 251 extern FLAC_API const char * const FLAC__StreamDecoderStateString[]; 252 253 254 /** Possible return values for the FLAC__stream_decoder_init_*() functions. 255 */ 256 typedef enum { 257 258 FLAC__STREAM_DECODER_INIT_STATUS_OK = 0, 259 /**< Initialization was successful. */ 260 261 FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER, 262 /**< The library was not compiled with support for the given container 263 * format. 264 */ 265 266 FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS, 267 /**< A required callback was not supplied. */ 268 269 FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR, 270 /**< An error occurred allocating memory. */ 271 272 FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE, 273 /**< fopen() failed in FLAC__stream_decoder_init_file() or 274 * FLAC__stream_decoder_init_ogg_file(). */ 275 276 FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED 277 /**< FLAC__stream_decoder_init_*() was called when the decoder was 278 * already initialized, usually because 279 * FLAC__stream_decoder_finish() was not called. 280 */ 281 282 } FLAC__StreamDecoderInitStatus; 283 284 /** Maps a FLAC__StreamDecoderInitStatus to a C string. 285 * 286 * Using a FLAC__StreamDecoderInitStatus as the index to this array 287 * will give the string equivalent. The contents should not be modified. 288 */ 289 extern FLAC_API const char * const FLAC__StreamDecoderInitStatusString[]; 290 291 292 /** Return values for the FLAC__StreamDecoder read callback. 293 */ 294 typedef enum { 295 296 FLAC__STREAM_DECODER_READ_STATUS_CONTINUE, 297 /**< The read was OK and decoding can continue. */ 298 299 FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM, 300 /**< The read was attempted while at the end of the stream. Note that 301 * the client must only return this value when the read callback was 302 * called when already at the end of the stream. Otherwise, if the read 303 * itself moves to the end of the stream, the client should still return 304 * the data and \c FLAC__STREAM_DECODER_READ_STATUS_CONTINUE, and then on 305 * the next read callback it should return 306 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM with a byte count 307 * of \c 0. 308 */ 309 310 FLAC__STREAM_DECODER_READ_STATUS_ABORT 311 /**< An unrecoverable error occurred. The decoder will return from the process call. */ 312 313 } FLAC__StreamDecoderReadStatus; 314 315 /** Maps a FLAC__StreamDecoderReadStatus to a C string. 316 * 317 * Using a FLAC__StreamDecoderReadStatus as the index to this array 318 * will give the string equivalent. The contents should not be modified. 319 */ 320 extern FLAC_API const char * const FLAC__StreamDecoderReadStatusString[]; 321 322 323 /** Return values for the FLAC__StreamDecoder seek callback. 324 */ 325 typedef enum { 326 327 FLAC__STREAM_DECODER_SEEK_STATUS_OK, 328 /**< The seek was OK and decoding can continue. */ 329 330 FLAC__STREAM_DECODER_SEEK_STATUS_ERROR, 331 /**< An unrecoverable error occurred. The decoder will return from the process call. */ 332 333 FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED 334 /**< Client does not support seeking. */ 335 336 } FLAC__StreamDecoderSeekStatus; 337 338 /** Maps a FLAC__StreamDecoderSeekStatus to a C string. 339 * 340 * Using a FLAC__StreamDecoderSeekStatus as the index to this array 341 * will give the string equivalent. The contents should not be modified. 342 */ 343 extern FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[]; 344 345 346 /** Return values for the FLAC__StreamDecoder tell callback. 347 */ 348 typedef enum { 349 350 FLAC__STREAM_DECODER_TELL_STATUS_OK, 351 /**< The tell was OK and decoding can continue. */ 352 353 FLAC__STREAM_DECODER_TELL_STATUS_ERROR, 354 /**< An unrecoverable error occurred. The decoder will return from the process call. */ 355 356 FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED 357 /**< Client does not support telling the position. */ 358 359 } FLAC__StreamDecoderTellStatus; 360 361 /** Maps a FLAC__StreamDecoderTellStatus to a C string. 362 * 363 * Using a FLAC__StreamDecoderTellStatus as the index to this array 364 * will give the string equivalent. The contents should not be modified. 365 */ 366 extern FLAC_API const char * const FLAC__StreamDecoderTellStatusString[]; 367 368 369 /** Return values for the FLAC__StreamDecoder length callback. 370 */ 371 typedef enum { 372 373 FLAC__STREAM_DECODER_LENGTH_STATUS_OK, 374 /**< The length call was OK and decoding can continue. */ 375 376 FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR, 377 /**< An unrecoverable error occurred. The decoder will return from the process call. */ 378 379 FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED 380 /**< Client does not support reporting the length. */ 381 382 } FLAC__StreamDecoderLengthStatus; 383 384 /** Maps a FLAC__StreamDecoderLengthStatus to a C string. 385 * 386 * Using a FLAC__StreamDecoderLengthStatus as the index to this array 387 * will give the string equivalent. The contents should not be modified. 388 */ 389 extern FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[]; 390 391 392 /** Return values for the FLAC__StreamDecoder write callback. 393 */ 394 typedef enum { 395 396 FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE, 397 /**< The write was OK and decoding can continue. */ 398 399 FLAC__STREAM_DECODER_WRITE_STATUS_ABORT 400 /**< An unrecoverable error occurred. The decoder will return from the process call. */ 401 402 } FLAC__StreamDecoderWriteStatus; 403 404 /** Maps a FLAC__StreamDecoderWriteStatus to a C string. 405 * 406 * Using a FLAC__StreamDecoderWriteStatus as the index to this array 407 * will give the string equivalent. The contents should not be modified. 408 */ 409 extern FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[]; 410 411 412 /** Possible values passed back to the FLAC__StreamDecoder error callback. 413 * \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC is the generic catch- 414 * all. The rest could be caused by bad sync (false synchronization on 415 * data that is not the start of a frame) or corrupted data. The error 416 * itself is the decoder's best guess at what happened assuming a correct 417 * sync. For example \c FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER 418 * could be caused by a correct sync on the start of a frame, but some 419 * data in the frame header was corrupted. Or it could be the result of 420 * syncing on a point the stream that looked like the starting of a frame 421 * but was not. \c FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM 422 * could be because the decoder encountered a valid frame made by a future 423 * version of the encoder which it cannot parse, or because of a false 424 * sync making it appear as though an encountered frame was generated by 425 * a future encoder. 426 */ 427 typedef enum { 428 429 FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, 430 /**< An error in the stream caused the decoder to lose synchronization. */ 431 432 FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, 433 /**< The decoder encountered a corrupted frame header. */ 434 435 FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH, 436 /**< The frame's data did not match the CRC in the footer. */ 437 438 FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM 439 /**< The decoder encountered reserved fields in use in the stream. */ 440 441 } FLAC__StreamDecoderErrorStatus; 442 443 /** Maps a FLAC__StreamDecoderErrorStatus to a C string. 444 * 445 * Using a FLAC__StreamDecoderErrorStatus as the index to this array 446 * will give the string equivalent. The contents should not be modified. 447 */ 448 extern FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[]; 449 450 451 /*********************************************************************** 452 * 453 * class FLAC__StreamDecoder 454 * 455 ***********************************************************************/ 456 457 struct FLAC__StreamDecoderProtected; 458 struct FLAC__StreamDecoderPrivate; 459 /** The opaque structure definition for the stream decoder type. 460 * See the \link flac_stream_decoder stream decoder module \endlink 461 * for a detailed description. 462 */ 463 typedef struct { 464 struct FLAC__StreamDecoderProtected *protected_; /* avoid the C++ keyword 'protected' */ 465 struct FLAC__StreamDecoderPrivate *private_; /* avoid the C++ keyword 'private' */ 466 } FLAC__StreamDecoder; 467 468 /** Signature for the read callback. 469 * 470 * A function pointer matching this signature must be passed to 471 * FLAC__stream_decoder_init*_stream(). The supplied function will be 472 * called when the decoder needs more input data. The address of the 473 * buffer to be filled is supplied, along with the number of bytes the 474 * buffer can hold. The callback may choose to supply less data and 475 * modify the byte count but must be careful not to overflow the buffer. 476 * The callback then returns a status code chosen from 477 * FLAC__StreamDecoderReadStatus. 478 * 479 * Here is an example of a read callback for stdio streams: 480 * \code 481 * FLAC__StreamDecoderReadStatus read_cb(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data) 482 * { 483 * FILE *file = ((MyClientData*)client_data)->file; 484 * if(*bytes > 0) { 485 * *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, file); 486 * if(ferror(file)) 487 * return FLAC__STREAM_DECODER_READ_STATUS_ABORT; 488 * else if(*bytes == 0) 489 * return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM; 490 * else 491 * return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE; 492 * } 493 * else 494 * return FLAC__STREAM_DECODER_READ_STATUS_ABORT; 495 * } 496 * \endcode 497 * 498 * \note In general, FLAC__StreamDecoder functions which change the 499 * state should not be called on the \a decoder while in the callback. 500 * 501 * \param decoder The decoder instance calling the callback. 502 * \param buffer A pointer to a location for the callee to store 503 * data to be decoded. 504 * \param bytes A pointer to the size of the buffer. On entry 505 * to the callback, it contains the maximum number 506 * of bytes that may be stored in \a buffer. The 507 * callee must set it to the actual number of bytes 508 * stored (0 in case of error or end-of-stream) before 509 * returning. 510 * \param client_data The callee's client data set through 511 * FLAC__stream_decoder_init_*(). 512 * \retval FLAC__StreamDecoderReadStatus 513 * The callee's return status. Note that the callback should return 514 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM if and only if 515 * zero bytes were read and there is no more data to be read. 516 */ 517 typedef FLAC__StreamDecoderReadStatus (*FLAC__StreamDecoderReadCallback)(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data); 518 519 /** Signature for the seek callback. 520 * 521 * A function pointer matching this signature may be passed to 522 * FLAC__stream_decoder_init*_stream(). The supplied function will be 523 * called when the decoder needs to seek the input stream. The decoder 524 * will pass the absolute byte offset to seek to, 0 meaning the 525 * beginning of the stream. 526 * 527 * Here is an example of a seek callback for stdio streams: 528 * \code 529 * FLAC__StreamDecoderSeekStatus seek_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data) 530 * { 531 * FILE *file = ((MyClientData*)client_data)->file; 532 * if(file == stdin) 533 * return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED; 534 * else if(fseeko(file, (off_t)absolute_byte_offset, SEEK_SET) < 0) 535 * return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR; 536 * else 537 * return FLAC__STREAM_DECODER_SEEK_STATUS_OK; 538 * } 539 * \endcode 540 * 541 * \note In general, FLAC__StreamDecoder functions which change the 542 * state should not be called on the \a decoder while in the callback. 543 * 544 * \param decoder The decoder instance calling the callback. 545 * \param absolute_byte_offset The offset from the beginning of the stream 546 * to seek to. 547 * \param client_data The callee's client data set through 548 * FLAC__stream_decoder_init_*(). 549 * \retval FLAC__StreamDecoderSeekStatus 550 * The callee's return status. 551 */ 552 typedef FLAC__StreamDecoderSeekStatus (*FLAC__StreamDecoderSeekCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data); 553 554 /** Signature for the tell callback. 555 * 556 * A function pointer matching this signature may be passed to 557 * FLAC__stream_decoder_init*_stream(). The supplied function will be 558 * called when the decoder wants to know the current position of the 559 * stream. The callback should return the byte offset from the 560 * beginning of the stream. 561 * 562 * Here is an example of a tell callback for stdio streams: 563 * \code 564 * FLAC__StreamDecoderTellStatus tell_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data) 565 * { 566 * FILE *file = ((MyClientData*)client_data)->file; 567 * off_t pos; 568 * if(file == stdin) 569 * return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED; 570 * else if((pos = ftello(file)) < 0) 571 * return FLAC__STREAM_DECODER_TELL_STATUS_ERROR; 572 * else { 573 * *absolute_byte_offset = (FLAC__uint64)pos; 574 * return FLAC__STREAM_DECODER_TELL_STATUS_OK; 575 * } 576 * } 577 * \endcode 578 * 579 * \note In general, FLAC__StreamDecoder functions which change the 580 * state should not be called on the \a decoder while in the callback. 581 * 582 * \param decoder The decoder instance calling the callback. 583 * \param absolute_byte_offset A pointer to storage for the current offset 584 * from the beginning of the stream. 585 * \param client_data The callee's client data set through 586 * FLAC__stream_decoder_init_*(). 587 * \retval FLAC__StreamDecoderTellStatus 588 * The callee's return status. 589 */ 590 typedef FLAC__StreamDecoderTellStatus (*FLAC__StreamDecoderTellCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data); 591 592 /** Signature for the length callback. 593 * 594 * A function pointer matching this signature may be passed to 595 * FLAC__stream_decoder_init*_stream(). The supplied function will be 596 * called when the decoder wants to know the total length of the stream 597 * in bytes. 598 * 599 * Here is an example of a length callback for stdio streams: 600 * \code 601 * FLAC__StreamDecoderLengthStatus length_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data) 602 * { 603 * FILE *file = ((MyClientData*)client_data)->file; 604 * struct stat filestats; 605 * 606 * if(file == stdin) 607 * return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED; 608 * else if(fstat(fileno(file), &filestats) != 0) 609 * return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR; 610 * else { 611 * *stream_length = (FLAC__uint64)filestats.st_size; 612 * return FLAC__STREAM_DECODER_LENGTH_STATUS_OK; 613 * } 614 * } 615 * \endcode 616 * 617 * \note In general, FLAC__StreamDecoder functions which change the 618 * state should not be called on the \a decoder while in the callback. 619 * 620 * \param decoder The decoder instance calling the callback. 621 * \param stream_length A pointer to storage for the length of the stream 622 * in bytes. 623 * \param client_data The callee's client data set through 624 * FLAC__stream_decoder_init_*(). 625 * \retval FLAC__StreamDecoderLengthStatus 626 * The callee's return status. 627 */ 628 typedef FLAC__StreamDecoderLengthStatus (*FLAC__StreamDecoderLengthCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data); 629 630 /** Signature for the EOF callback. 631 * 632 * A function pointer matching this signature may be passed to 633 * FLAC__stream_decoder_init*_stream(). The supplied function will be 634 * called when the decoder needs to know if the end of the stream has 635 * been reached. 636 * 637 * Here is an example of a EOF callback for stdio streams: 638 * FLAC__bool eof_cb(const FLAC__StreamDecoder *decoder, void *client_data) 639 * \code 640 * { 641 * FILE *file = ((MyClientData*)client_data)->file; 642 * return feof(file)? true : false; 643 * } 644 * \endcode 645 * 646 * \note In general, FLAC__StreamDecoder functions which change the 647 * state should not be called on the \a decoder while in the callback. 648 * 649 * \param decoder The decoder instance calling the callback. 650 * \param client_data The callee's client data set through 651 * FLAC__stream_decoder_init_*(). 652 * \retval FLAC__bool 653 * \c true if the currently at the end of the stream, else \c false. 654 */ 655 typedef FLAC__bool (*FLAC__StreamDecoderEofCallback)(const FLAC__StreamDecoder *decoder, void *client_data); 656 657 /** Signature for the write callback. 658 * 659 * A function pointer matching this signature must be passed to one of 660 * the FLAC__stream_decoder_init_*() functions. 661 * The supplied function will be called when the decoder has decoded a 662 * single audio frame. The decoder will pass the frame metadata as well 663 * as an array of pointers (one for each channel) pointing to the 664 * decoded audio. 665 * 666 * \note In general, FLAC__StreamDecoder functions which change the 667 * state should not be called on the \a decoder while in the callback. 668 * 669 * \param decoder The decoder instance calling the callback. 670 * \param frame The description of the decoded frame. See 671 * FLAC__Frame. 672 * \param buffer An array of pointers to decoded channels of data. 673 * Each pointer will point to an array of signed 674 * samples of length \a frame->header.blocksize. 675 * Channels will be ordered according to the FLAC 676 * specification; see the documentation for the 677 * <A HREF="../format.html#frame_header">frame header</A>. 678 * \param client_data The callee's client data set through 679 * FLAC__stream_decoder_init_*(). 680 * \retval FLAC__StreamDecoderWriteStatus 681 * The callee's return status. 682 */ 683 typedef FLAC__StreamDecoderWriteStatus (*FLAC__StreamDecoderWriteCallback)(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data); 684 685 /** Signature for the metadata callback. 686 * 687 * A function pointer matching this signature must be passed to one of 688 * the FLAC__stream_decoder_init_*() functions. 689 * The supplied function will be called when the decoder has decoded a 690 * metadata block. In a valid FLAC file there will always be one 691 * \c STREAMINFO block, followed by zero or more other metadata blocks. 692 * These will be supplied by the decoder in the same order as they 693 * appear in the stream and always before the first audio frame (i.e. 694 * write callback). The metadata block that is passed in must not be 695 * modified, and it doesn't live beyond the callback, so you should make 696 * a copy of it with FLAC__metadata_object_clone() if you will need it 697 * elsewhere. Since metadata blocks can potentially be large, by 698 * default the decoder only calls the metadata callback for the 699 * \c STREAMINFO block; you can instruct the decoder to pass or filter 700 * other blocks with FLAC__stream_decoder_set_metadata_*() calls. 701 * 702 * \note In general, FLAC__StreamDecoder functions which change the 703 * state should not be called on the \a decoder while in the callback. 704 * 705 * \param decoder The decoder instance calling the callback. 706 * \param metadata The decoded metadata block. 707 * \param client_data The callee's client data set through 708 * FLAC__stream_decoder_init_*(). 709 */ 710 typedef void (*FLAC__StreamDecoderMetadataCallback)(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data); 711 712 /** Signature for the error callback. 713 * 714 * A function pointer matching this signature must be passed to one of 715 * the FLAC__stream_decoder_init_*() functions. 716 * The supplied function will be called whenever an error occurs during 717 * decoding. 718 * 719 * \note In general, FLAC__StreamDecoder functions which change the 720 * state should not be called on the \a decoder while in the callback. 721 * 722 * \param decoder The decoder instance calling the callback. 723 * \param status The error encountered by the decoder. 724 * \param client_data The callee's client data set through 725 * FLAC__stream_decoder_init_*(). 726 */ 727 typedef void (*FLAC__StreamDecoderErrorCallback)(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data); 728 729 730 /*********************************************************************** 731 * 732 * Class constructor/destructor 733 * 734 ***********************************************************************/ 735 736 /** Create a new stream decoder instance. The instance is created with 737 * default settings; see the individual FLAC__stream_decoder_set_*() 738 * functions for each setting's default. 739 * 740 * \retval FLAC__StreamDecoder* 741 * \c NULL if there was an error allocating memory, else the new instance. 742 */ 743 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void); 744 745 /** Free a decoder instance. Deletes the object pointed to by \a decoder. 746 * 747 * \param decoder A pointer to an existing decoder. 748 * \assert 749 * \code decoder != NULL \endcode 750 */ 751 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder); 752 753 754 /*********************************************************************** 755 * 756 * Public class method prototypes 757 * 758 ***********************************************************************/ 759 760 /** Set the serial number for the FLAC stream within the Ogg container. 761 * The default behavior is to use the serial number of the first Ogg 762 * page. Setting a serial number here will explicitly specify which 763 * stream is to be decoded. 764 * 765 * \note 766 * This does not need to be set for native FLAC decoding. 767 * 768 * \default \c use serial number of first page 769 * \param decoder A decoder instance to set. 770 * \param serial_number See above. 771 * \assert 772 * \code decoder != NULL \endcode 773 * \retval FLAC__bool 774 * \c false if the decoder is already initialized, else \c true. 775 */ 776 FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long serial_number); 777 778 /** Set the "MD5 signature checking" flag. If \c true, the decoder will 779 * compute the MD5 signature of the unencoded audio data while decoding 780 * and compare it to the signature from the STREAMINFO block, if it 781 * exists, during FLAC__stream_decoder_finish(). 782 * 783 * MD5 signature checking will be turned off (until the next 784 * FLAC__stream_decoder_reset()) if there is no signature in the 785 * STREAMINFO block or when a seek is attempted. 786 * 787 * Clients that do not use the MD5 check should leave this off to speed 788 * up decoding. 789 * 790 * \default \c false 791 * \param decoder A decoder instance to set. 792 * \param value Flag value (see above). 793 * \assert 794 * \code decoder != NULL \endcode 795 * \retval FLAC__bool 796 * \c false if the decoder is already initialized, else \c true. 797 */ 798 FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value); 799 800 /** Direct the decoder to pass on all metadata blocks of type \a type. 801 * 802 * \default By default, only the \c STREAMINFO block is returned via the 803 * metadata callback. 804 * \param decoder A decoder instance to set. 805 * \param type See above. 806 * \assert 807 * \code decoder != NULL \endcode 808 * \a type is valid 809 * \retval FLAC__bool 810 * \c false if the decoder is already initialized, else \c true. 811 */ 812 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type); 813 814 /** Direct the decoder to pass on all APPLICATION metadata blocks of the 815 * given \a id. 816 * 817 * \default By default, only the \c STREAMINFO block is returned via the 818 * metadata callback. 819 * \param decoder A decoder instance to set. 820 * \param id See above. 821 * \assert 822 * \code decoder != NULL \endcode 823 * \code id != NULL \endcode 824 * \retval FLAC__bool 825 * \c false if the decoder is already initialized, else \c true. 826 */ 827 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]); 828 829 /** Direct the decoder to pass on all metadata blocks of any type. 830 * 831 * \default By default, only the \c STREAMINFO block is returned via the 832 * metadata callback. 833 * \param decoder A decoder instance to set. 834 * \assert 835 * \code decoder != NULL \endcode 836 * \retval FLAC__bool 837 * \c false if the decoder is already initialized, else \c true. 838 */ 839 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder); 840 841 /** Direct the decoder to filter out all metadata blocks of type \a type. 842 * 843 * \default By default, only the \c STREAMINFO block is returned via the 844 * metadata callback. 845 * \param decoder A decoder instance to set. 846 * \param type See above. 847 * \assert 848 * \code decoder != NULL \endcode 849 * \a type is valid 850 * \retval FLAC__bool 851 * \c false if the decoder is already initialized, else \c true. 852 */ 853 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type); 854 855 /** Direct the decoder to filter out all APPLICATION metadata blocks of 856 * the given \a id. 857 * 858 * \default By default, only the \c STREAMINFO block is returned via the 859 * metadata callback. 860 * \param decoder A decoder instance to set. 861 * \param id See above. 862 * \assert 863 * \code decoder != NULL \endcode 864 * \code id != NULL \endcode 865 * \retval FLAC__bool 866 * \c false if the decoder is already initialized, else \c true. 867 */ 868 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]); 869 870 /** Direct the decoder to filter out all metadata blocks of any type. 871 * 872 * \default By default, only the \c STREAMINFO block is returned via the 873 * metadata callback. 874 * \param decoder A decoder instance to set. 875 * \assert 876 * \code decoder != NULL \endcode 877 * \retval FLAC__bool 878 * \c false if the decoder is already initialized, else \c true. 879 */ 880 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder); 881 882 /** Get the current decoder state. 883 * 884 * \param decoder A decoder instance to query. 885 * \assert 886 * \code decoder != NULL \endcode 887 * \retval FLAC__StreamDecoderState 888 * The current decoder state. 889 */ 890 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder); 891 892 /** Get the current decoder state as a C string. 893 * 894 * \param decoder A decoder instance to query. 895 * \assert 896 * \code decoder != NULL \endcode 897 * \retval const char * 898 * The decoder state as a C string. Do not modify the contents. 899 */ 900 FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder); 901 902 /** Get the "MD5 signature checking" flag. 903 * This is the value of the setting, not whether or not the decoder is 904 * currently checking the MD5 (remember, it can be turned off automatically 905 * by a seek). When the decoder is reset the flag will be restored to the 906 * value returned by this function. 907 * 908 * \param decoder A decoder instance to query. 909 * \assert 910 * \code decoder != NULL \endcode 911 * \retval FLAC__bool 912 * See above. 913 */ 914 FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder); 915 916 /** Get the total number of samples in the stream being decoded. 917 * Will only be valid after decoding has started and will contain the 918 * value from the \c STREAMINFO block. A value of \c 0 means "unknown". 919 * 920 * \param decoder A decoder instance to query. 921 * \assert 922 * \code decoder != NULL \endcode 923 * \retval unsigned 924 * See above. 925 */ 926 FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder); 927 928 /** Get the current number of channels in the stream being decoded. 929 * Will only be valid after decoding has started and will contain the 930 * value from the most recently decoded frame header. 931 * 932 * \param decoder A decoder instance to query. 933 * \assert 934 * \code decoder != NULL \endcode 935 * \retval unsigned 936 * See above. 937 */ 938 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder); 939 940 /** Get the current channel assignment in the stream being decoded. 941 * Will only be valid after decoding has started and will contain the 942 * value from the most recently decoded frame header. 943 * 944 * \param decoder A decoder instance to query. 945 * \assert 946 * \code decoder != NULL \endcode 947 * \retval FLAC__ChannelAssignment 948 * See above. 949 */ 950 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder); 951 952 /** Get the current sample resolution in the stream being decoded. 953 * Will only be valid after decoding has started and will contain the 954 * value from the most recently decoded frame header. 955 * 956 * \param decoder A decoder instance to query. 957 * \assert 958 * \code decoder != NULL \endcode 959 * \retval unsigned 960 * See above. 961 */ 962 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder); 963 964 /** Get the current sample rate in Hz of the stream being decoded. 965 * Will only be valid after decoding has started and will contain the 966 * value from the most recently decoded frame header. 967 * 968 * \param decoder A decoder instance to query. 969 * \assert 970 * \code decoder != NULL \endcode 971 * \retval unsigned 972 * See above. 973 */ 974 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder); 975 976 /** Get the current blocksize of the stream being decoded. 977 * Will only be valid after decoding has started and will contain the 978 * value from the most recently decoded frame header. 979 * 980 * \param decoder A decoder instance to query. 981 * \assert 982 * \code decoder != NULL \endcode 983 * \retval unsigned 984 * See above. 985 */ 986 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder); 987 988 /** Returns the decoder's current read position within the stream. 989 * The position is the byte offset from the start of the stream. 990 * Bytes before this position have been fully decoded. Note that 991 * there may still be undecoded bytes in the decoder's read FIFO. 992 * The returned position is correct even after a seek. 993 * 994 * \warning This function currently only works for native FLAC, 995 * not Ogg FLAC streams. 996 * 997 * \param decoder A decoder instance to query. 998 * \param position Address at which to return the desired position. 999 * \assert 1000 * \code decoder != NULL \endcode 1001 * \code position != NULL \endcode 1002 * \retval FLAC__bool 1003 * \c true if successful, \c false if the stream is not native FLAC, 1004 * or there was an error from the 'tell' callback or it returned 1005 * \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED. 1006 */ 1007 FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position); 1008 1009 /** Initialize the decoder instance to decode native FLAC streams. 1010 * 1011 * This flavor of initialization sets up the decoder to decode from a 1012 * native FLAC stream. I/O is performed via callbacks to the client. 1013 * For decoding from a plain file via filename or open FILE*, 1014 * FLAC__stream_decoder_init_file() and FLAC__stream_decoder_init_FILE() 1015 * provide a simpler interface. 1016 * 1017 * This function should be called after FLAC__stream_decoder_new() and 1018 * FLAC__stream_decoder_set_*() but before any of the 1019 * FLAC__stream_decoder_process_*() functions. Will set and return the 1020 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1021 * if initialization succeeded. 1022 * 1023 * \param decoder An uninitialized decoder instance. 1024 * \param read_callback See FLAC__StreamDecoderReadCallback. This 1025 * pointer must not be \c NULL. 1026 * \param seek_callback See FLAC__StreamDecoderSeekCallback. This 1027 * pointer may be \c NULL if seeking is not 1028 * supported. If \a seek_callback is not \c NULL then a 1029 * \a tell_callback, \a length_callback, and \a eof_callback must also be supplied. 1030 * Alternatively, a dummy seek callback that just 1031 * returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED 1032 * may also be supplied, all though this is slightly 1033 * less efficient for the decoder. 1034 * \param tell_callback See FLAC__StreamDecoderTellCallback. This 1035 * pointer may be \c NULL if not supported by the client. If 1036 * \a seek_callback is not \c NULL then a 1037 * \a tell_callback must also be supplied. 1038 * Alternatively, a dummy tell callback that just 1039 * returns \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED 1040 * may also be supplied, all though this is slightly 1041 * less efficient for the decoder. 1042 * \param length_callback See FLAC__StreamDecoderLengthCallback. This 1043 * pointer may be \c NULL if not supported by the client. If 1044 * \a seek_callback is not \c NULL then a 1045 * \a length_callback must also be supplied. 1046 * Alternatively, a dummy length callback that just 1047 * returns \c FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED 1048 * may also be supplied, all though this is slightly 1049 * less efficient for the decoder. 1050 * \param eof_callback See FLAC__StreamDecoderEofCallback. This 1051 * pointer may be \c NULL if not supported by the client. If 1052 * \a seek_callback is not \c NULL then a 1053 * \a eof_callback must also be supplied. 1054 * Alternatively, a dummy length callback that just 1055 * returns \c false 1056 * may also be supplied, all though this is slightly 1057 * less efficient for the decoder. 1058 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1059 * pointer must not be \c NULL. 1060 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1061 * pointer may be \c NULL if the callback is not 1062 * desired. 1063 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1064 * pointer must not be \c NULL. 1065 * \param client_data This value will be supplied to callbacks in their 1066 * \a client_data argument. 1067 * \assert 1068 * \code decoder != NULL \endcode 1069 * \retval FLAC__StreamDecoderInitStatus 1070 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1071 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1072 */ 1073 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream( 1074 FLAC__StreamDecoder *decoder, 1075 FLAC__StreamDecoderReadCallback read_callback, 1076 FLAC__StreamDecoderSeekCallback seek_callback, 1077 FLAC__StreamDecoderTellCallback tell_callback, 1078 FLAC__StreamDecoderLengthCallback length_callback, 1079 FLAC__StreamDecoderEofCallback eof_callback, 1080 FLAC__StreamDecoderWriteCallback write_callback, 1081 FLAC__StreamDecoderMetadataCallback metadata_callback, 1082 FLAC__StreamDecoderErrorCallback error_callback, 1083 void *client_data 1084 ); 1085 1086 /** Initialize the decoder instance to decode Ogg FLAC streams. 1087 * 1088 * This flavor of initialization sets up the decoder to decode from a 1089 * FLAC stream in an Ogg container. I/O is performed via callbacks to the 1090 * client. For decoding from a plain file via filename or open FILE*, 1091 * FLAC__stream_decoder_init_ogg_file() and FLAC__stream_decoder_init_ogg_FILE() 1092 * provide a simpler interface. 1093 * 1094 * This function should be called after FLAC__stream_decoder_new() and 1095 * FLAC__stream_decoder_set_*() but before any of the 1096 * FLAC__stream_decoder_process_*() functions. Will set and return the 1097 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1098 * if initialization succeeded. 1099 * 1100 * \note Support for Ogg FLAC in the library is optional. If this 1101 * library has been built without support for Ogg FLAC, this function 1102 * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. 1103 * 1104 * \param decoder An uninitialized decoder instance. 1105 * \param read_callback See FLAC__StreamDecoderReadCallback. This 1106 * pointer must not be \c NULL. 1107 * \param seek_callback See FLAC__StreamDecoderSeekCallback. This 1108 * pointer may be \c NULL if seeking is not 1109 * supported. If \a seek_callback is not \c NULL then a 1110 * \a tell_callback, \a length_callback, and \a eof_callback must also be supplied. 1111 * Alternatively, a dummy seek callback that just 1112 * returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED 1113 * may also be supplied, all though this is slightly 1114 * less efficient for the decoder. 1115 * \param tell_callback See FLAC__StreamDecoderTellCallback. This 1116 * pointer may be \c NULL if not supported by the client. If 1117 * \a seek_callback is not \c NULL then a 1118 * \a tell_callback must also be supplied. 1119 * Alternatively, a dummy tell callback that just 1120 * returns \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED 1121 * may also be supplied, all though this is slightly 1122 * less efficient for the decoder. 1123 * \param length_callback See FLAC__StreamDecoderLengthCallback. This 1124 * pointer may be \c NULL if not supported by the client. If 1125 * \a seek_callback is not \c NULL then a 1126 * \a length_callback must also be supplied. 1127 * Alternatively, a dummy length callback that just 1128 * returns \c FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED 1129 * may also be supplied, all though this is slightly 1130 * less efficient for the decoder. 1131 * \param eof_callback See FLAC__StreamDecoderEofCallback. This 1132 * pointer may be \c NULL if not supported by the client. If 1133 * \a seek_callback is not \c NULL then a 1134 * \a eof_callback must also be supplied. 1135 * Alternatively, a dummy length callback that just 1136 * returns \c false 1137 * may also be supplied, all though this is slightly 1138 * less efficient for the decoder. 1139 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1140 * pointer must not be \c NULL. 1141 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1142 * pointer may be \c NULL if the callback is not 1143 * desired. 1144 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1145 * pointer must not be \c NULL. 1146 * \param client_data This value will be supplied to callbacks in their 1147 * \a client_data argument. 1148 * \assert 1149 * \code decoder != NULL \endcode 1150 * \retval FLAC__StreamDecoderInitStatus 1151 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1152 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1153 */ 1154 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream( 1155 FLAC__StreamDecoder *decoder, 1156 FLAC__StreamDecoderReadCallback read_callback, 1157 FLAC__StreamDecoderSeekCallback seek_callback, 1158 FLAC__StreamDecoderTellCallback tell_callback, 1159 FLAC__StreamDecoderLengthCallback length_callback, 1160 FLAC__StreamDecoderEofCallback eof_callback, 1161 FLAC__StreamDecoderWriteCallback write_callback, 1162 FLAC__StreamDecoderMetadataCallback metadata_callback, 1163 FLAC__StreamDecoderErrorCallback error_callback, 1164 void *client_data 1165 ); 1166 1167 /** Initialize the decoder instance to decode native FLAC files. 1168 * 1169 * This flavor of initialization sets up the decoder to decode from a 1170 * plain native FLAC file. For non-stdio streams, you must use 1171 * FLAC__stream_decoder_init_stream() and provide callbacks for the I/O. 1172 * 1173 * This function should be called after FLAC__stream_decoder_new() and 1174 * FLAC__stream_decoder_set_*() but before any of the 1175 * FLAC__stream_decoder_process_*() functions. Will set and return the 1176 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1177 * if initialization succeeded. 1178 * 1179 * \param decoder An uninitialized decoder instance. 1180 * \param file An open FLAC file. The file should have been 1181 * opened with mode \c "rb" and rewound. The file 1182 * becomes owned by the decoder and should not be 1183 * manipulated by the client while decoding. 1184 * Unless \a file is \c stdin, it will be closed 1185 * when FLAC__stream_decoder_finish() is called. 1186 * Note however that seeking will not work when 1187 * decoding from \c stdout since it is not seekable. 1188 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1189 * pointer must not be \c NULL. 1190 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1191 * pointer may be \c NULL if the callback is not 1192 * desired. 1193 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1194 * pointer must not be \c NULL. 1195 * \param client_data This value will be supplied to callbacks in their 1196 * \a client_data argument. 1197 * \assert 1198 * \code decoder != NULL \endcode 1199 * \code file != NULL \endcode 1200 * \retval FLAC__StreamDecoderInitStatus 1201 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1202 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1203 */ 1204 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE( 1205 FLAC__StreamDecoder *decoder, 1206 FILE *file, 1207 FLAC__StreamDecoderWriteCallback write_callback, 1208 FLAC__StreamDecoderMetadataCallback metadata_callback, 1209 FLAC__StreamDecoderErrorCallback error_callback, 1210 void *client_data 1211 ); 1212 1213 /** Initialize the decoder instance to decode Ogg FLAC files. 1214 * 1215 * This flavor of initialization sets up the decoder to decode from a 1216 * plain Ogg FLAC file. For non-stdio streams, you must use 1217 * FLAC__stream_decoder_init_ogg_stream() and provide callbacks for the I/O. 1218 * 1219 * This function should be called after FLAC__stream_decoder_new() and 1220 * FLAC__stream_decoder_set_*() but before any of the 1221 * FLAC__stream_decoder_process_*() functions. Will set and return the 1222 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1223 * if initialization succeeded. 1224 * 1225 * \note Support for Ogg FLAC in the library is optional. If this 1226 * library has been built without support for Ogg FLAC, this function 1227 * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. 1228 * 1229 * \param decoder An uninitialized decoder instance. 1230 * \param file An open FLAC file. The file should have been 1231 * opened with mode \c "rb" and rewound. The file 1232 * becomes owned by the decoder and should not be 1233 * manipulated by the client while decoding. 1234 * Unless \a file is \c stdin, it will be closed 1235 * when FLAC__stream_decoder_finish() is called. 1236 * Note however that seeking will not work when 1237 * decoding from \c stdout since it is not seekable. 1238 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1239 * pointer must not be \c NULL. 1240 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1241 * pointer may be \c NULL if the callback is not 1242 * desired. 1243 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1244 * pointer must not be \c NULL. 1245 * \param client_data This value will be supplied to callbacks in their 1246 * \a client_data argument. 1247 * \assert 1248 * \code decoder != NULL \endcode 1249 * \code file != NULL \endcode 1250 * \retval FLAC__StreamDecoderInitStatus 1251 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1252 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1253 */ 1254 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE( 1255 FLAC__StreamDecoder *decoder, 1256 FILE *file, 1257 FLAC__StreamDecoderWriteCallback write_callback, 1258 FLAC__StreamDecoderMetadataCallback metadata_callback, 1259 FLAC__StreamDecoderErrorCallback error_callback, 1260 void *client_data 1261 ); 1262 1263 /** Initialize the decoder instance to decode native FLAC files. 1264 * 1265 * This flavor of initialization sets up the decoder to decode from a plain 1266 * native FLAC file. If POSIX fopen() semantics are not sufficient, (for 1267 * example, with Unicode filenames on Windows), you must use 1268 * FLAC__stream_decoder_init_FILE(), or FLAC__stream_decoder_init_stream() 1269 * and provide callbacks for the I/O. 1270 * 1271 * This function should be called after FLAC__stream_decoder_new() and 1272 * FLAC__stream_decoder_set_*() but before any of the 1273 * FLAC__stream_decoder_process_*() functions. Will set and return the 1274 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1275 * if initialization succeeded. 1276 * 1277 * \param decoder An uninitialized decoder instance. 1278 * \param filename The name of the file to decode from. The file will 1279 * be opened with fopen(). Use \c NULL to decode from 1280 * \c stdin. Note that \c stdin is not seekable. 1281 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1282 * pointer must not be \c NULL. 1283 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1284 * pointer may be \c NULL if the callback is not 1285 * desired. 1286 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1287 * pointer must not be \c NULL. 1288 * \param client_data This value will be supplied to callbacks in their 1289 * \a client_data argument. 1290 * \assert 1291 * \code decoder != NULL \endcode 1292 * \retval FLAC__StreamDecoderInitStatus 1293 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1294 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1295 */ 1296 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file( 1297 FLAC__StreamDecoder *decoder, 1298 const char *filename, 1299 FLAC__StreamDecoderWriteCallback write_callback, 1300 FLAC__StreamDecoderMetadataCallback metadata_callback, 1301 FLAC__StreamDecoderErrorCallback error_callback, 1302 void *client_data 1303 ); 1304 1305 /** Initialize the decoder instance to decode Ogg FLAC files. 1306 * 1307 * This flavor of initialization sets up the decoder to decode from a plain 1308 * Ogg FLAC file. If POSIX fopen() semantics are not sufficient, (for 1309 * example, with Unicode filenames on Windows), you must use 1310 * FLAC__stream_decoder_init_ogg_FILE(), or FLAC__stream_decoder_init_ogg_stream() 1311 * and provide callbacks for the I/O. 1312 * 1313 * This function should be called after FLAC__stream_decoder_new() and 1314 * FLAC__stream_decoder_set_*() but before any of the 1315 * FLAC__stream_decoder_process_*() functions. Will set and return the 1316 * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA 1317 * if initialization succeeded. 1318 * 1319 * \note Support for Ogg FLAC in the library is optional. If this 1320 * library has been built without support for Ogg FLAC, this function 1321 * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. 1322 * 1323 * \param decoder An uninitialized decoder instance. 1324 * \param filename The name of the file to decode from. The file will 1325 * be opened with fopen(). Use \c NULL to decode from 1326 * \c stdin. Note that \c stdin is not seekable. 1327 * \param write_callback See FLAC__StreamDecoderWriteCallback. This 1328 * pointer must not be \c NULL. 1329 * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This 1330 * pointer may be \c NULL if the callback is not 1331 * desired. 1332 * \param error_callback See FLAC__StreamDecoderErrorCallback. This 1333 * pointer must not be \c NULL. 1334 * \param client_data This value will be supplied to callbacks in their 1335 * \a client_data argument. 1336 * \assert 1337 * \code decoder != NULL \endcode 1338 * \retval FLAC__StreamDecoderInitStatus 1339 * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; 1340 * see FLAC__StreamDecoderInitStatus for the meanings of other return values. 1341 */ 1342 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file( 1343 FLAC__StreamDecoder *decoder, 1344 const char *filename, 1345 FLAC__StreamDecoderWriteCallback write_callback, 1346 FLAC__StreamDecoderMetadataCallback metadata_callback, 1347 FLAC__StreamDecoderErrorCallback error_callback, 1348 void *client_data 1349 ); 1350 1351 /** Finish the decoding process. 1352 * Flushes the decoding buffer, releases resources, resets the decoder 1353 * settings to their defaults, and returns the decoder state to 1354 * FLAC__STREAM_DECODER_UNINITIALIZED. 1355 * 1356 * In the event of a prematurely-terminated decode, it is not strictly 1357 * necessary to call this immediately before FLAC__stream_decoder_delete() 1358 * but it is good practice to match every FLAC__stream_decoder_init_*() 1359 * with a FLAC__stream_decoder_finish(). 1360 * 1361 * \param decoder An uninitialized decoder instance. 1362 * \assert 1363 * \code decoder != NULL \endcode 1364 * \retval FLAC__bool 1365 * \c false if MD5 checking is on AND a STREAMINFO block was available 1366 * AND the MD5 signature in the STREAMINFO block was non-zero AND the 1367 * signature does not match the one computed by the decoder; else 1368 * \c true. 1369 */ 1370 FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder); 1371 1372 /** Flush the stream input. 1373 * The decoder's input buffer will be cleared and the state set to 1374 * \c FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC. This will also turn 1375 * off MD5 checking. 1376 * 1377 * \param decoder A decoder instance. 1378 * \assert 1379 * \code decoder != NULL \endcode 1380 * \retval FLAC__bool 1381 * \c true if successful, else \c false if a memory allocation 1382 * error occurs (in which case the state will be set to 1383 * \c FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR). 1384 */ 1385 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder); 1386 1387 /** Reset the decoding process. 1388 * The decoder's input buffer will be cleared and the state set to 1389 * \c FLAC__STREAM_DECODER_SEARCH_FOR_METADATA. This is similar to 1390 * FLAC__stream_decoder_finish() except that the settings are 1391 * preserved; there is no need to call FLAC__stream_decoder_init_*() 1392 * before decoding again. MD5 checking will be restored to its original 1393 * setting. 1394 * 1395 * If the decoder is seekable, or was initialized with 1396 * FLAC__stream_decoder_init*_FILE() or FLAC__stream_decoder_init*_file(), 1397 * the decoder will also attempt to seek to the beginning of the file. 1398 * If this rewind fails, this function will return \c false. It follows 1399 * that FLAC__stream_decoder_reset() cannot be used when decoding from 1400 * \c stdin. 1401 * 1402 * If the decoder was initialized with FLAC__stream_encoder_init*_stream() 1403 * and is not seekable (i.e. no seek callback was provided or the seek 1404 * callback returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED), it 1405 * is the duty of the client to start feeding data from the beginning of 1406 * the stream on the next FLAC__stream_decoder_process() or 1407 * FLAC__stream_decoder_process_interleaved() call. 1408 * 1409 * \param decoder A decoder instance. 1410 * \assert 1411 * \code decoder != NULL \endcode 1412 * \retval FLAC__bool 1413 * \c true if successful, else \c false if a memory allocation occurs 1414 * (in which case the state will be set to 1415 * \c FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR) or a seek error 1416 * occurs (the state will be unchanged). 1417 */ 1418 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder); 1419 1420 /** Decode one metadata block or audio frame. 1421 * This version instructs the decoder to decode a either a single metadata 1422 * block or a single frame and stop, unless the callbacks return a fatal 1423 * error or the read callback returns 1424 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. 1425 * 1426 * As the decoder needs more input it will call the read callback. 1427 * Depending on what was decoded, the metadata or write callback will be 1428 * called with the decoded metadata block or audio frame. 1429 * 1430 * Unless there is a fatal read error or end of stream, this function 1431 * will return once one whole frame is decoded. In other words, if the 1432 * stream is not synchronized or points to a corrupt frame header, the 1433 * decoder will continue to try and resync until it gets to a valid 1434 * frame, then decode one frame, then return. If the decoder points to 1435 * a frame whose frame CRC in the frame footer does not match the 1436 * computed frame CRC, this function will issue a 1437 * FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH error to the 1438 * error callback, and return, having decoded one complete, although 1439 * corrupt, frame. (Such corrupted frames are sent as silence of the 1440 * correct length to the write callback.) 1441 * 1442 * \param decoder An initialized decoder instance. 1443 * \assert 1444 * \code decoder != NULL \endcode 1445 * \retval FLAC__bool 1446 * \c false if any fatal read, write, or memory allocation error 1447 * occurred (meaning decoding must stop), else \c true; for more 1448 * information about the decoder, check the decoder state with 1449 * FLAC__stream_decoder_get_state(). 1450 */ 1451 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder); 1452 1453 /** Decode until the end of the metadata. 1454 * This version instructs the decoder to decode from the current position 1455 * and continue until all the metadata has been read, or until the 1456 * callbacks return a fatal error or the read callback returns 1457 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. 1458 * 1459 * As the decoder needs more input it will call the read callback. 1460 * As each metadata block is decoded, the metadata callback will be called 1461 * with the decoded metadata. 1462 * 1463 * \param decoder An initialized decoder instance. 1464 * \assert 1465 * \code decoder != NULL \endcode 1466 * \retval FLAC__bool 1467 * \c false if any fatal read, write, or memory allocation error 1468 * occurred (meaning decoding must stop), else \c true; for more 1469 * information about the decoder, check the decoder state with 1470 * FLAC__stream_decoder_get_state(). 1471 */ 1472 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder); 1473 1474 /** Decode until the end of the stream. 1475 * This version instructs the decoder to decode from the current position 1476 * and continue until the end of stream (the read callback returns 1477 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM), or until the 1478 * callbacks return a fatal error. 1479 * 1480 * As the decoder needs more input it will call the read callback. 1481 * As each metadata block and frame is decoded, the metadata or write 1482 * callback will be called with the decoded metadata or frame. 1483 * 1484 * \param decoder An initialized decoder instance. 1485 * \assert 1486 * \code decoder != NULL \endcode 1487 * \retval FLAC__bool 1488 * \c false if any fatal read, write, or memory allocation error 1489 * occurred (meaning decoding must stop), else \c true; for more 1490 * information about the decoder, check the decoder state with 1491 * FLAC__stream_decoder_get_state(). 1492 */ 1493 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder); 1494 1495 /** Skip one audio frame. 1496 * This version instructs the decoder to 'skip' a single frame and stop, 1497 * unless the callbacks return a fatal error or the read callback returns 1498 * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. 1499 * 1500 * The decoding flow is the same as what occurs when 1501 * FLAC__stream_decoder_process_single() is called to process an audio 1502 * frame, except that this function does not decode the parsed data into 1503 * PCM or call the write callback. The integrity of the frame is still 1504 * checked the same way as in the other process functions. 1505 * 1506 * This function will return once one whole frame is skipped, in the 1507 * same way that FLAC__stream_decoder_process_single() will return once 1508 * one whole frame is decoded. 1509 * 1510 * This function can be used in more quickly determining FLAC frame 1511 * boundaries when decoding of the actual data is not needed, for 1512 * example when an application is separating a FLAC stream into frames 1513 * for editing or storing in a container. To do this, the application 1514 * can use FLAC__stream_decoder_skip_single_frame() to quickly advance 1515 * to the next frame, then use 1516 * FLAC__stream_decoder_get_decode_position() to find the new frame 1517 * boundary. 1518 * 1519 * This function should only be called when the stream has advanced 1520 * past all the metadata, otherwise it will return \c false. 1521 * 1522 * \param decoder An initialized decoder instance not in a metadata 1523 * state. 1524 * \assert 1525 * \code decoder != NULL \endcode 1526 * \retval FLAC__bool 1527 * \c false if any fatal read, write, or memory allocation error 1528 * occurred (meaning decoding must stop), or if the decoder 1529 * is in the FLAC__STREAM_DECODER_SEARCH_FOR_METADATA or 1530 * FLAC__STREAM_DECODER_READ_METADATA state, else \c true; for more 1531 * information about the decoder, check the decoder state with 1532 * FLAC__stream_decoder_get_state(). 1533 */ 1534 FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder); 1535 1536 /** Flush the input and seek to an absolute sample. 1537 * Decoding will resume at the given sample. Note that because of 1538 * this, the next write callback may contain a partial block. The 1539 * client must support seeking the input or this function will fail 1540 * and return \c false. Furthermore, if the decoder state is 1541 * \c FLAC__STREAM_DECODER_SEEK_ERROR, then the decoder must be flushed 1542 * with FLAC__stream_decoder_flush() or reset with 1543 * FLAC__stream_decoder_reset() before decoding can continue. 1544 * 1545 * \param decoder A decoder instance. 1546 * \param sample The target sample number to seek to. 1547 * \assert 1548 * \code decoder != NULL \endcode 1549 * \retval FLAC__bool 1550 * \c true if successful, else \c false. 1551 */ 1552 FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample); 1553 1554 /* \} */ 1555 1556 #ifdef __cplusplus 1557 } 1558 #endif 1559 1560 #endif 1561