1 /* libFLAC - Free Lossless Audio Codec library 2 * Copyright (C) 2000,2001,2002,2003,2004,2005,2006,2007 Josh Coalson 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 * - Neither the name of the Xiph.org Foundation nor the names of its 16 * contributors may be used to endorse or promote products derived from 17 * this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR 23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef FLAC__FORMAT_H 33 #define FLAC__FORMAT_H 34 35 #include "export.h" 36 #include "ordinals.h" 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /** \file include/FLAC/format.h 43 * 44 * \brief 45 * This module contains structure definitions for the representation 46 * of FLAC format components in memory. These are the basic 47 * structures used by the rest of the interfaces. 48 * 49 * See the detailed documentation in the 50 * \link flac_format format \endlink module. 51 */ 52 53 /** \defgroup flac_format FLAC/format.h: format components 54 * \ingroup flac 55 * 56 * \brief 57 * This module contains structure definitions for the representation 58 * of FLAC format components in memory. These are the basic 59 * structures used by the rest of the interfaces. 60 * 61 * First, you should be familiar with the 62 * <A HREF="../format.html">FLAC format</A>. Many of the values here 63 * follow directly from the specification. As a user of libFLAC, the 64 * interesting parts really are the structures that describe the frame 65 * header and metadata blocks. 66 * 67 * The format structures here are very primitive, designed to store 68 * information in an efficient way. Reading information from the 69 * structures is easy but creating or modifying them directly is 70 * more complex. For the most part, as a user of a library, editing 71 * is not necessary; however, for metadata blocks it is, so there are 72 * convenience functions provided in the \link flac_metadata metadata 73 * module \endlink to simplify the manipulation of metadata blocks. 74 * 75 * \note 76 * It's not the best convention, but symbols ending in _LEN are in bits 77 * and _LENGTH are in bytes. _LENGTH symbols are \#defines instead of 78 * global variables because they are usually used when declaring byte 79 * arrays and some compilers require compile-time knowledge of array 80 * sizes when declared on the stack. 81 * 82 * \{ 83 */ 84 85 86 /* 87 Most of the values described in this file are defined by the FLAC 88 format specification. There is nothing to tune here. 89 */ 90 91 /** The largest legal metadata type code. */ 92 #define FLAC__MAX_METADATA_TYPE_CODE (126u) 93 94 /** The minimum block size, in samples, permitted by the format. */ 95 #define FLAC__MIN_BLOCK_SIZE (16u) 96 97 /** The maximum block size, in samples, permitted by the format. */ 98 #define FLAC__MAX_BLOCK_SIZE (65535u) 99 100 /** The maximum block size, in samples, permitted by the FLAC subset for 101 * sample rates up to 48kHz. */ 102 #define FLAC__SUBSET_MAX_BLOCK_SIZE_48000HZ (4608u) 103 104 /** The maximum number of channels permitted by the format. */ 105 #define FLAC__MAX_CHANNELS (8u) 106 107 /** The minimum sample resolution permitted by the format. */ 108 #define FLAC__MIN_BITS_PER_SAMPLE (4u) 109 110 /** The maximum sample resolution permitted by the format. */ 111 #define FLAC__MAX_BITS_PER_SAMPLE (32u) 112 113 /** The maximum sample resolution permitted by libFLAC. 114 * 115 * \warning 116 * FLAC__MAX_BITS_PER_SAMPLE is the limit of the FLAC format. However, 117 * the reference encoder/decoder is currently limited to 24 bits because 118 * of prevalent 32-bit math, so make sure and use this value when 119 * appropriate. 120 */ 121 #define FLAC__REFERENCE_CODEC_MAX_BITS_PER_SAMPLE (24u) 122 123 /** The maximum sample rate permitted by the format. The value is 124 * ((2 ^ 16) - 1) * 10; see <A HREF="../format.html">FLAC format</A> 125 * as to why. 126 */ 127 #define FLAC__MAX_SAMPLE_RATE (655350u) 128 129 /** The maximum LPC order permitted by the format. */ 130 #define FLAC__MAX_LPC_ORDER (32u) 131 132 /** The maximum LPC order permitted by the FLAC subset for sample rates 133 * up to 48kHz. */ 134 #define FLAC__SUBSET_MAX_LPC_ORDER_48000HZ (12u) 135 136 /** The minimum quantized linear predictor coefficient precision 137 * permitted by the format. 138 */ 139 #define FLAC__MIN_QLP_COEFF_PRECISION (5u) 140 141 /** The maximum quantized linear predictor coefficient precision 142 * permitted by the format. 143 */ 144 #define FLAC__MAX_QLP_COEFF_PRECISION (15u) 145 146 /** The maximum order of the fixed predictors permitted by the format. */ 147 #define FLAC__MAX_FIXED_ORDER (4u) 148 149 /** The maximum Rice partition order permitted by the format. */ 150 #define FLAC__MAX_RICE_PARTITION_ORDER (15u) 151 152 /** The maximum Rice partition order permitted by the FLAC Subset. */ 153 #define FLAC__SUBSET_MAX_RICE_PARTITION_ORDER (8u) 154 155 /** The version string of the release, stamped onto the libraries and binaries. 156 * 157 * \note 158 * This does not correspond to the shared library version number, which 159 * is used to determine binary compatibility. 160 */ 161 extern FLAC_API const char *FLAC__VERSION_STRING; 162 163 /** The vendor string inserted by the encoder into the VORBIS_COMMENT block. 164 * This is a NUL-terminated ASCII string; when inserted into the 165 * VORBIS_COMMENT the trailing null is stripped. 166 */ 167 extern FLAC_API const char *FLAC__VENDOR_STRING; 168 169 /** The byte string representation of the beginning of a FLAC stream. */ 170 extern FLAC_API const FLAC__byte FLAC__STREAM_SYNC_STRING[4]; /* = "fLaC" */ 171 172 /** The 32-bit integer big-endian representation of the beginning of 173 * a FLAC stream. 174 */ 175 extern FLAC_API const unsigned FLAC__STREAM_SYNC; /* = 0x664C6143 */ 176 177 /** The length of the FLAC signature in bits. */ 178 extern FLAC_API const unsigned FLAC__STREAM_SYNC_LEN; /* = 32 bits */ 179 180 /** The length of the FLAC signature in bytes. */ 181 #define FLAC__STREAM_SYNC_LENGTH (4u) 182 183 184 /***************************************************************************** 185 * 186 * Subframe structures 187 * 188 *****************************************************************************/ 189 190 /*****************************************************************************/ 191 192 /** An enumeration of the available entropy coding methods. */ 193 typedef enum { 194 FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE = 0, 195 /**< Residual is coded by partitioning into contexts, each with it's own 196 * 4-bit Rice parameter. */ 197 198 FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2 = 1 199 /**< Residual is coded by partitioning into contexts, each with it's own 200 * 5-bit Rice parameter. */ 201 } FLAC__EntropyCodingMethodType; 202 203 /** Maps a FLAC__EntropyCodingMethodType to a C string. 204 * 205 * Using a FLAC__EntropyCodingMethodType as the index to this array will 206 * give the string equivalent. The contents should not be modified. 207 */ 208 extern FLAC_API const char * const FLAC__EntropyCodingMethodTypeString[]; 209 210 211 /** Contents of a Rice partitioned residual 212 */ 213 typedef struct { 214 215 unsigned *parameters; 216 /**< The Rice parameters for each context. */ 217 218 unsigned *raw_bits; 219 /**< Widths for escape-coded partitions. Will be non-zero for escaped 220 * partitions and zero for unescaped partitions. 221 */ 222 223 unsigned capacity_by_order; 224 /**< The capacity of the \a parameters and \a raw_bits arrays 225 * specified as an order, i.e. the number of array elements 226 * allocated is 2 ^ \a capacity_by_order. 227 */ 228 } FLAC__EntropyCodingMethod_PartitionedRiceContents; 229 230 /** Header for a Rice partitioned residual. (c.f. <A HREF="../format.html#partitioned_rice">format specification</A>) 231 */ 232 typedef struct { 233 234 unsigned order; 235 /**< The partition order, i.e. # of contexts = 2 ^ \a order. */ 236 237 const FLAC__EntropyCodingMethod_PartitionedRiceContents *contents; 238 /**< The context's Rice parameters and/or raw bits. */ 239 240 } FLAC__EntropyCodingMethod_PartitionedRice; 241 242 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN; /**< == 4 (bits) */ 243 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; /**< == 4 (bits) */ 244 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN; /**< == 5 (bits) */ 245 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN; /**< == 5 (bits) */ 246 247 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER; 248 /**< == (1<<FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN)-1 */ 249 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER; 250 /**< == (1<<FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN)-1 */ 251 252 /** Header for the entropy coding method. (c.f. <A HREF="../format.html#residual">format specification</A>) 253 */ 254 typedef struct { 255 FLAC__EntropyCodingMethodType type; 256 union { 257 FLAC__EntropyCodingMethod_PartitionedRice partitioned_rice; 258 } data; 259 } FLAC__EntropyCodingMethod; 260 261 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_TYPE_LEN; /**< == 2 (bits) */ 262 263 /*****************************************************************************/ 264 265 /** An enumeration of the available subframe types. */ 266 typedef enum { 267 FLAC__SUBFRAME_TYPE_CONSTANT = 0, /**< constant signal */ 268 FLAC__SUBFRAME_TYPE_VERBATIM = 1, /**< uncompressed signal */ 269 FLAC__SUBFRAME_TYPE_FIXED = 2, /**< fixed polynomial prediction */ 270 FLAC__SUBFRAME_TYPE_LPC = 3 /**< linear prediction */ 271 } FLAC__SubframeType; 272 273 /** Maps a FLAC__SubframeType to a C string. 274 * 275 * Using a FLAC__SubframeType as the index to this array will 276 * give the string equivalent. The contents should not be modified. 277 */ 278 extern FLAC_API const char * const FLAC__SubframeTypeString[]; 279 280 281 /** CONSTANT subframe. (c.f. <A HREF="../format.html#subframe_constant">format specification</A>) 282 */ 283 typedef struct { 284 FLAC__int32 value; /**< The constant signal value. */ 285 } FLAC__Subframe_Constant; 286 287 288 /** VERBATIM subframe. (c.f. <A HREF="../format.html#subframe_verbatim">format specification</A>) 289 */ 290 typedef struct { 291 const FLAC__int32 *data; /**< A pointer to verbatim signal. */ 292 } FLAC__Subframe_Verbatim; 293 294 295 /** FIXED subframe. (c.f. <A HREF="../format.html#subframe_fixed">format specification</A>) 296 */ 297 typedef struct { 298 FLAC__EntropyCodingMethod entropy_coding_method; 299 /**< The residual coding method. */ 300 301 unsigned order; 302 /**< The polynomial order. */ 303 304 FLAC__int32 warmup[FLAC__MAX_FIXED_ORDER]; 305 /**< Warmup samples to prime the predictor, length == order. */ 306 307 const FLAC__int32 *residual; 308 /**< The residual signal, length == (blocksize minus order) samples. */ 309 } FLAC__Subframe_Fixed; 310 311 312 /** LPC subframe. (c.f. <A HREF="../format.html#subframe_lpc">format specification</A>) 313 */ 314 typedef struct { 315 FLAC__EntropyCodingMethod entropy_coding_method; 316 /**< The residual coding method. */ 317 318 unsigned order; 319 /**< The FIR order. */ 320 321 unsigned qlp_coeff_precision; 322 /**< Quantized FIR filter coefficient precision in bits. */ 323 324 int quantization_level; 325 /**< The qlp coeff shift needed. */ 326 327 FLAC__int32 qlp_coeff[FLAC__MAX_LPC_ORDER]; 328 /**< FIR filter coefficients. */ 329 330 FLAC__int32 warmup[FLAC__MAX_LPC_ORDER]; 331 /**< Warmup samples to prime the predictor, length == order. */ 332 333 const FLAC__int32 *residual; 334 /**< The residual signal, length == (blocksize minus order) samples. */ 335 } FLAC__Subframe_LPC; 336 337 extern FLAC_API const unsigned FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN; /**< == 4 (bits) */ 338 extern FLAC_API const unsigned FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN; /**< == 5 (bits) */ 339 340 341 /** FLAC subframe structure. (c.f. <A HREF="../format.html#subframe">format specification</A>) 342 */ 343 typedef struct { 344 FLAC__SubframeType type; 345 union { 346 FLAC__Subframe_Constant constant; 347 FLAC__Subframe_Fixed fixed; 348 FLAC__Subframe_LPC lpc; 349 FLAC__Subframe_Verbatim verbatim; 350 } data; 351 unsigned wasted_bits; 352 } FLAC__Subframe; 353 354 /** == 1 (bit) 355 * 356 * This used to be a zero-padding bit (hence the name 357 * FLAC__SUBFRAME_ZERO_PAD_LEN) but is now a reserved bit. It still has a 358 * mandatory value of \c 0 but in the future may take on the value \c 0 or \c 1 359 * to mean something else. 360 */ 361 extern FLAC_API const unsigned FLAC__SUBFRAME_ZERO_PAD_LEN; 362 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_LEN; /**< == 6 (bits) */ 363 extern FLAC_API const unsigned FLAC__SUBFRAME_WASTED_BITS_FLAG_LEN; /**< == 1 (bit) */ 364 365 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_CONSTANT_BYTE_ALIGNED_MASK; /**< = 0x00 */ 366 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_VERBATIM_BYTE_ALIGNED_MASK; /**< = 0x02 */ 367 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_FIXED_BYTE_ALIGNED_MASK; /**< = 0x10 */ 368 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_LPC_BYTE_ALIGNED_MASK; /**< = 0x40 */ 369 370 /*****************************************************************************/ 371 372 373 /***************************************************************************** 374 * 375 * Frame structures 376 * 377 *****************************************************************************/ 378 379 /** An enumeration of the available channel assignments. */ 380 typedef enum { 381 FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT = 0, /**< independent channels */ 382 FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE = 1, /**< left+side stereo */ 383 FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE = 2, /**< right+side stereo */ 384 FLAC__CHANNEL_ASSIGNMENT_MID_SIDE = 3 /**< mid+side stereo */ 385 } FLAC__ChannelAssignment; 386 387 /** Maps a FLAC__ChannelAssignment to a C string. 388 * 389 * Using a FLAC__ChannelAssignment as the index to this array will 390 * give the string equivalent. The contents should not be modified. 391 */ 392 extern FLAC_API const char * const FLAC__ChannelAssignmentString[]; 393 394 /** An enumeration of the possible frame numbering methods. */ 395 typedef enum { 396 FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER, /**< number contains the frame number */ 397 FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER /**< number contains the sample number of first sample in frame */ 398 } FLAC__FrameNumberType; 399 400 /** Maps a FLAC__FrameNumberType to a C string. 401 * 402 * Using a FLAC__FrameNumberType as the index to this array will 403 * give the string equivalent. The contents should not be modified. 404 */ 405 extern FLAC_API const char * const FLAC__FrameNumberTypeString[]; 406 407 408 /** FLAC frame header structure. (c.f. <A HREF="../format.html#frame_header">format specification</A>) 409 */ 410 typedef struct { 411 unsigned blocksize; 412 /**< The number of samples per subframe. */ 413 414 unsigned sample_rate; 415 /**< The sample rate in Hz. */ 416 417 unsigned channels; 418 /**< The number of channels (== number of subframes). */ 419 420 FLAC__ChannelAssignment channel_assignment; 421 /**< The channel assignment for the frame. */ 422 423 unsigned bits_per_sample; 424 /**< The sample resolution. */ 425 426 FLAC__FrameNumberType number_type; 427 /**< The numbering scheme used for the frame. As a convenience, the 428 * decoder will always convert a frame number to a sample number because 429 * the rules are complex. */ 430 431 union { 432 FLAC__uint32 frame_number; 433 FLAC__uint64 sample_number; 434 } number; 435 /**< The frame number or sample number of first sample in frame; 436 * use the \a number_type value to determine which to use. */ 437 438 FLAC__uint8 crc; 439 /**< CRC-8 (polynomial = x^8 + x^2 + x^1 + x^0, initialized with 0) 440 * of the raw frame header bytes, meaning everything before the CRC byte 441 * including the sync code. 442 */ 443 } FLAC__FrameHeader; 444 445 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SYNC; /**< == 0x3ffe; the frame header sync code */ 446 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SYNC_LEN; /**< == 14 (bits) */ 447 extern FLAC_API const unsigned FLAC__FRAME_HEADER_RESERVED_LEN; /**< == 1 (bits) */ 448 extern FLAC_API const unsigned FLAC__FRAME_HEADER_BLOCKING_STRATEGY_LEN; /**< == 1 (bits) */ 449 extern FLAC_API const unsigned FLAC__FRAME_HEADER_BLOCK_SIZE_LEN; /**< == 4 (bits) */ 450 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SAMPLE_RATE_LEN; /**< == 4 (bits) */ 451 extern FLAC_API const unsigned FLAC__FRAME_HEADER_CHANNEL_ASSIGNMENT_LEN; /**< == 4 (bits) */ 452 extern FLAC_API const unsigned FLAC__FRAME_HEADER_BITS_PER_SAMPLE_LEN; /**< == 3 (bits) */ 453 extern FLAC_API const unsigned FLAC__FRAME_HEADER_ZERO_PAD_LEN; /**< == 1 (bit) */ 454 extern FLAC_API const unsigned FLAC__FRAME_HEADER_CRC_LEN; /**< == 8 (bits) */ 455 456 457 /** FLAC frame footer structure. (c.f. <A HREF="../format.html#frame_footer">format specification</A>) 458 */ 459 typedef struct { 460 FLAC__uint16 crc; 461 /**< CRC-16 (polynomial = x^16 + x^15 + x^2 + x^0, initialized with 462 * 0) of the bytes before the crc, back to and including the frame header 463 * sync code. 464 */ 465 } FLAC__FrameFooter; 466 467 extern FLAC_API const unsigned FLAC__FRAME_FOOTER_CRC_LEN; /**< == 16 (bits) */ 468 469 470 /** FLAC frame structure. (c.f. <A HREF="../format.html#frame">format specification</A>) 471 */ 472 typedef struct { 473 FLAC__FrameHeader header; 474 FLAC__Subframe subframes[FLAC__MAX_CHANNELS]; 475 FLAC__FrameFooter footer; 476 } FLAC__Frame; 477 478 /*****************************************************************************/ 479 480 481 /***************************************************************************** 482 * 483 * Meta-data structures 484 * 485 *****************************************************************************/ 486 487 /** An enumeration of the available metadata block types. */ 488 typedef enum { 489 490 FLAC__METADATA_TYPE_STREAMINFO = 0, 491 /**< <A HREF="../format.html#metadata_block_streaminfo">STREAMINFO</A> block */ 492 493 FLAC__METADATA_TYPE_PADDING = 1, 494 /**< <A HREF="../format.html#metadata_block_padding">PADDING</A> block */ 495 496 FLAC__METADATA_TYPE_APPLICATION = 2, 497 /**< <A HREF="../format.html#metadata_block_application">APPLICATION</A> block */ 498 499 FLAC__METADATA_TYPE_SEEKTABLE = 3, 500 /**< <A HREF="../format.html#metadata_block_seektable">SEEKTABLE</A> block */ 501 502 FLAC__METADATA_TYPE_VORBIS_COMMENT = 4, 503 /**< <A HREF="../format.html#metadata_block_vorbis_comment">VORBISCOMMENT</A> block (a.k.a. FLAC tags) */ 504 505 FLAC__METADATA_TYPE_CUESHEET = 5, 506 /**< <A HREF="../format.html#metadata_block_cuesheet">CUESHEET</A> block */ 507 508 FLAC__METADATA_TYPE_PICTURE = 6, 509 /**< <A HREF="../format.html#metadata_block_picture">PICTURE</A> block */ 510 511 FLAC__METADATA_TYPE_UNDEFINED = 7 512 /**< marker to denote beginning of undefined type range; this number will increase as new metadata types are added */ 513 514 } FLAC__MetadataType; 515 516 /** Maps a FLAC__MetadataType to a C string. 517 * 518 * Using a FLAC__MetadataType as the index to this array will 519 * give the string equivalent. The contents should not be modified. 520 */ 521 extern FLAC_API const char * const FLAC__MetadataTypeString[]; 522 523 524 /** FLAC STREAMINFO structure. (c.f. <A HREF="../format.html#metadata_block_streaminfo">format specification</A>) 525 */ 526 typedef struct { 527 unsigned min_blocksize, max_blocksize; 528 unsigned min_framesize, max_framesize; 529 unsigned sample_rate; 530 unsigned channels; 531 unsigned bits_per_sample; 532 FLAC__uint64 total_samples; 533 FLAC__byte md5sum[16]; 534 } FLAC__StreamMetadata_StreamInfo; 535 536 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN; /**< == 16 (bits) */ 537 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN; /**< == 16 (bits) */ 538 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN; /**< == 24 (bits) */ 539 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN; /**< == 24 (bits) */ 540 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN; /**< == 20 (bits) */ 541 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN; /**< == 3 (bits) */ 542 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN; /**< == 5 (bits) */ 543 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN; /**< == 36 (bits) */ 544 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MD5SUM_LEN; /**< == 128 (bits) */ 545 546 /** The total stream length of the STREAMINFO block in bytes. */ 547 #define FLAC__STREAM_METADATA_STREAMINFO_LENGTH (34u) 548 549 /** FLAC PADDING structure. (c.f. <A HREF="../format.html#metadata_block_padding">format specification</A>) 550 */ 551 typedef struct { 552 int dummy; 553 /**< Conceptually this is an empty struct since we don't store the 554 * padding bytes. Empty structs are not allowed by some C compilers, 555 * hence the dummy. 556 */ 557 } FLAC__StreamMetadata_Padding; 558 559 560 /** FLAC APPLICATION structure. (c.f. <A HREF="../format.html#metadata_block_application">format specification</A>) 561 */ 562 typedef struct { 563 FLAC__byte id[4]; 564 FLAC__byte *data; 565 } FLAC__StreamMetadata_Application; 566 567 extern FLAC_API const unsigned FLAC__STREAM_METADATA_APPLICATION_ID_LEN; /**< == 32 (bits) */ 568 569 /** SeekPoint structure used in SEEKTABLE blocks. (c.f. <A HREF="../format.html#seekpoint">format specification</A>) 570 */ 571 typedef struct { 572 FLAC__uint64 sample_number; 573 /**< The sample number of the target frame. */ 574 575 FLAC__uint64 stream_offset; 576 /**< The offset, in bytes, of the target frame with respect to 577 * beginning of the first frame. */ 578 579 unsigned frame_samples; 580 /**< The number of samples in the target frame. */ 581 } FLAC__StreamMetadata_SeekPoint; 582 583 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN; /**< == 64 (bits) */ 584 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN; /**< == 64 (bits) */ 585 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN; /**< == 16 (bits) */ 586 587 /** The total stream length of a seek point in bytes. */ 588 #define FLAC__STREAM_METADATA_SEEKPOINT_LENGTH (18u) 589 590 /** The value used in the \a sample_number field of 591 * FLAC__StreamMetadataSeekPoint used to indicate a placeholder 592 * point (== 0xffffffffffffffff). 593 */ 594 extern FLAC_API const FLAC__uint64 FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER; 595 596 597 /** FLAC SEEKTABLE structure. (c.f. <A HREF="../format.html#metadata_block_seektable">format specification</A>) 598 * 599 * \note From the format specification: 600 * - The seek points must be sorted by ascending sample number. 601 * - Each seek point's sample number must be the first sample of the 602 * target frame. 603 * - Each seek point's sample number must be unique within the table. 604 * - Existence of a SEEKTABLE block implies a correct setting of 605 * total_samples in the stream_info block. 606 * - Behavior is undefined when more than one SEEKTABLE block is 607 * present in a stream. 608 */ 609 typedef struct { 610 unsigned num_points; 611 FLAC__StreamMetadata_SeekPoint *points; 612 } FLAC__StreamMetadata_SeekTable; 613 614 615 /** Vorbis comment entry structure used in VORBIS_COMMENT blocks. (c.f. <A HREF="../format.html#metadata_block_vorbis_comment">format specification</A>) 616 * 617 * For convenience, the APIs maintain a trailing NUL character at the end of 618 * \a entry which is not counted toward \a length, i.e. 619 * \code strlen(entry) == length \endcode 620 */ 621 typedef struct { 622 FLAC__uint32 length; 623 FLAC__byte *entry; 624 } FLAC__StreamMetadata_VorbisComment_Entry; 625 626 extern FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN; /**< == 32 (bits) */ 627 628 629 /** FLAC VORBIS_COMMENT structure. (c.f. <A HREF="../format.html#metadata_block_vorbis_comment">format specification</A>) 630 */ 631 typedef struct { 632 FLAC__StreamMetadata_VorbisComment_Entry vendor_string; 633 FLAC__uint32 num_comments; 634 FLAC__StreamMetadata_VorbisComment_Entry *comments; 635 } FLAC__StreamMetadata_VorbisComment; 636 637 extern FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN; /**< == 32 (bits) */ 638 639 640 /** FLAC CUESHEET track index structure. (See the 641 * <A HREF="../format.html#cuesheet_track_index">format specification</A> for 642 * the full description of each field.) 643 */ 644 typedef struct { 645 FLAC__uint64 offset; 646 /**< Offset in samples, relative to the track offset, of the index 647 * point. 648 */ 649 650 FLAC__byte number; 651 /**< The index point number. */ 652 } FLAC__StreamMetadata_CueSheet_Index; 653 654 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN; /**< == 64 (bits) */ 655 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN; /**< == 8 (bits) */ 656 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN; /**< == 3*8 (bits) */ 657 658 659 /** FLAC CUESHEET track structure. (See the 660 * <A HREF="../format.html#cuesheet_track">format specification</A> for 661 * the full description of each field.) 662 */ 663 typedef struct { 664 FLAC__uint64 offset; 665 /**< Track offset in samples, relative to the beginning of the FLAC audio stream. */ 666 667 FLAC__byte number; 668 /**< The track number. */ 669 670 char isrc[13]; 671 /**< Track ISRC. This is a 12-digit alphanumeric code plus a trailing \c NUL byte */ 672 673 unsigned type:1; 674 /**< The track type: 0 for audio, 1 for non-audio. */ 675 676 unsigned pre_emphasis:1; 677 /**< The pre-emphasis flag: 0 for no pre-emphasis, 1 for pre-emphasis. */ 678 679 FLAC__byte num_indices; 680 /**< The number of track index points. */ 681 682 FLAC__StreamMetadata_CueSheet_Index *indices; 683 /**< NULL if num_indices == 0, else pointer to array of index points. */ 684 685 } FLAC__StreamMetadata_CueSheet_Track; 686 687 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN; /**< == 64 (bits) */ 688 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN; /**< == 8 (bits) */ 689 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN; /**< == 12*8 (bits) */ 690 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN; /**< == 1 (bit) */ 691 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN; /**< == 1 (bit) */ 692 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN; /**< == 6+13*8 (bits) */ 693 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN; /**< == 8 (bits) */ 694 695 696 /** FLAC CUESHEET structure. (See the 697 * <A HREF="../format.html#metadata_block_cuesheet">format specification</A> 698 * for the full description of each field.) 699 */ 700 typedef struct { 701 char media_catalog_number[129]; 702 /**< Media catalog number, in ASCII printable characters 0x20-0x7e. In 703 * general, the media catalog number may be 0 to 128 bytes long; any 704 * unused characters should be right-padded with NUL characters. 705 */ 706 707 FLAC__uint64 lead_in; 708 /**< The number of lead-in samples. */ 709 710 FLAC__bool is_cd; 711 /**< \c true if CUESHEET corresponds to a Compact Disc, else \c false. */ 712 713 unsigned num_tracks; 714 /**< The number of tracks. */ 715 716 FLAC__StreamMetadata_CueSheet_Track *tracks; 717 /**< NULL if num_tracks == 0, else pointer to array of tracks. */ 718 719 } FLAC__StreamMetadata_CueSheet; 720 721 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN; /**< == 128*8 (bits) */ 722 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN; /**< == 64 (bits) */ 723 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN; /**< == 1 (bit) */ 724 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN; /**< == 7+258*8 (bits) */ 725 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN; /**< == 8 (bits) */ 726 727 728 /** An enumeration of the PICTURE types (see FLAC__StreamMetadataPicture and id3 v2.4 APIC tag). */ 729 typedef enum { 730 FLAC__STREAM_METADATA_PICTURE_TYPE_OTHER = 0, /**< Other */ 731 FLAC__STREAM_METADATA_PICTURE_TYPE_FILE_ICON_STANDARD = 1, /**< 32x32 pixels 'file icon' (PNG only) */ 732 FLAC__STREAM_METADATA_PICTURE_TYPE_FILE_ICON = 2, /**< Other file icon */ 733 FLAC__STREAM_METADATA_PICTURE_TYPE_FRONT_COVER = 3, /**< Cover (front) */ 734 FLAC__STREAM_METADATA_PICTURE_TYPE_BACK_COVER = 4, /**< Cover (back) */ 735 FLAC__STREAM_METADATA_PICTURE_TYPE_LEAFLET_PAGE = 5, /**< Leaflet page */ 736 FLAC__STREAM_METADATA_PICTURE_TYPE_MEDIA = 6, /**< Media (e.g. label side of CD) */ 737 FLAC__STREAM_METADATA_PICTURE_TYPE_LEAD_ARTIST = 7, /**< Lead artist/lead performer/soloist */ 738 FLAC__STREAM_METADATA_PICTURE_TYPE_ARTIST = 8, /**< Artist/performer */ 739 FLAC__STREAM_METADATA_PICTURE_TYPE_CONDUCTOR = 9, /**< Conductor */ 740 FLAC__STREAM_METADATA_PICTURE_TYPE_BAND = 10, /**< Band/Orchestra */ 741 FLAC__STREAM_METADATA_PICTURE_TYPE_COMPOSER = 11, /**< Composer */ 742 FLAC__STREAM_METADATA_PICTURE_TYPE_LYRICIST = 12, /**< Lyricist/text writer */ 743 FLAC__STREAM_METADATA_PICTURE_TYPE_RECORDING_LOCATION = 13, /**< Recording Location */ 744 FLAC__STREAM_METADATA_PICTURE_TYPE_DURING_RECORDING = 14, /**< During recording */ 745 FLAC__STREAM_METADATA_PICTURE_TYPE_DURING_PERFORMANCE = 15, /**< During performance */ 746 FLAC__STREAM_METADATA_PICTURE_TYPE_VIDEO_SCREEN_CAPTURE = 16, /**< Movie/video screen capture */ 747 FLAC__STREAM_METADATA_PICTURE_TYPE_FISH = 17, /**< A bright coloured fish */ 748 FLAC__STREAM_METADATA_PICTURE_TYPE_ILLUSTRATION = 18, /**< Illustration */ 749 FLAC__STREAM_METADATA_PICTURE_TYPE_BAND_LOGOTYPE = 19, /**< Band/artist logotype */ 750 FLAC__STREAM_METADATA_PICTURE_TYPE_PUBLISHER_LOGOTYPE = 20, /**< Publisher/Studio logotype */ 751 FLAC__STREAM_METADATA_PICTURE_TYPE_UNDEFINED 752 } FLAC__StreamMetadata_Picture_Type; 753 754 /** Maps a FLAC__StreamMetadata_Picture_Type to a C string. 755 * 756 * Using a FLAC__StreamMetadata_Picture_Type as the index to this array 757 * will give the string equivalent. The contents should not be 758 * modified. 759 */ 760 extern FLAC_API const char * const FLAC__StreamMetadata_Picture_TypeString[]; 761 762 /** FLAC PICTURE structure. (See the 763 * <A HREF="../format.html#metadata_block_picture">format specification</A> 764 * for the full description of each field.) 765 */ 766 typedef struct { 767 FLAC__StreamMetadata_Picture_Type type; 768 /**< The kind of picture stored. */ 769 770 char *mime_type; 771 /**< Picture data's MIME type, in ASCII printable characters 772 * 0x20-0x7e, NUL terminated. For best compatibility with players, 773 * use picture data of MIME type \c image/jpeg or \c image/png. A 774 * MIME type of '-->' is also allowed, in which case the picture 775 * data should be a complete URL. In file storage, the MIME type is 776 * stored as a 32-bit length followed by the ASCII string with no NUL 777 * terminator, but is converted to a plain C string in this structure 778 * for convenience. 779 */ 780 781 FLAC__byte *description; 782 /**< Picture's description in UTF-8, NUL terminated. In file storage, 783 * the description is stored as a 32-bit length followed by the UTF-8 784 * string with no NUL terminator, but is converted to a plain C string 785 * in this structure for convenience. 786 */ 787 788 FLAC__uint32 width; 789 /**< Picture's width in pixels. */ 790 791 FLAC__uint32 height; 792 /**< Picture's height in pixels. */ 793 794 FLAC__uint32 depth; 795 /**< Picture's color depth in bits-per-pixel. */ 796 797 FLAC__uint32 colors; 798 /**< For indexed palettes (like GIF), picture's number of colors (the 799 * number of palette entries), or \c 0 for non-indexed (i.e. 2^depth). 800 */ 801 802 FLAC__uint32 data_length; 803 /**< Length of binary picture data in bytes. */ 804 805 FLAC__byte *data; 806 /**< Binary picture data. */ 807 808 } FLAC__StreamMetadata_Picture; 809 810 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_TYPE_LEN; /**< == 32 (bits) */ 811 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN; /**< == 32 (bits) */ 812 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN; /**< == 32 (bits) */ 813 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN; /**< == 32 (bits) */ 814 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN; /**< == 32 (bits) */ 815 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN; /**< == 32 (bits) */ 816 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_COLORS_LEN; /**< == 32 (bits) */ 817 extern FLAC_API const unsigned FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN; /**< == 32 (bits) */ 818 819 820 /** Structure that is used when a metadata block of unknown type is loaded. 821 * The contents are opaque. The structure is used only internally to 822 * correctly handle unknown metadata. 823 */ 824 typedef struct { 825 FLAC__byte *data; 826 } FLAC__StreamMetadata_Unknown; 827 828 829 /** FLAC metadata block structure. (c.f. <A HREF="../format.html#metadata_block">format specification</A>) 830 */ 831 typedef struct { 832 FLAC__MetadataType type; 833 /**< The type of the metadata block; used determine which member of the 834 * \a data union to dereference. If type >= FLAC__METADATA_TYPE_UNDEFINED 835 * then \a data.unknown must be used. */ 836 837 FLAC__bool is_last; 838 /**< \c true if this metadata block is the last, else \a false */ 839 840 unsigned length; 841 /**< Length, in bytes, of the block data as it appears in the stream. */ 842 843 union { 844 FLAC__StreamMetadata_StreamInfo stream_info; 845 FLAC__StreamMetadata_Padding padding; 846 FLAC__StreamMetadata_Application application; 847 FLAC__StreamMetadata_SeekTable seek_table; 848 FLAC__StreamMetadata_VorbisComment vorbis_comment; 849 FLAC__StreamMetadata_CueSheet cue_sheet; 850 FLAC__StreamMetadata_Picture picture; 851 FLAC__StreamMetadata_Unknown unknown; 852 } data; 853 /**< Polymorphic block data; use the \a type value to determine which 854 * to use. */ 855 } FLAC__StreamMetadata; 856 857 extern FLAC_API const unsigned FLAC__STREAM_METADATA_IS_LAST_LEN; /**< == 1 (bit) */ 858 extern FLAC_API const unsigned FLAC__STREAM_METADATA_TYPE_LEN; /**< == 7 (bits) */ 859 extern FLAC_API const unsigned FLAC__STREAM_METADATA_LENGTH_LEN; /**< == 24 (bits) */ 860 861 /** The total stream length of a metadata block header in bytes. */ 862 #define FLAC__STREAM_METADATA_HEADER_LENGTH (4u) 863 864 /*****************************************************************************/ 865 866 867 /***************************************************************************** 868 * 869 * Utility functions 870 * 871 *****************************************************************************/ 872 873 /** Tests that a sample rate is valid for FLAC. 874 * 875 * \param sample_rate The sample rate to test for compliance. 876 * \retval FLAC__bool 877 * \c true if the given sample rate conforms to the specification, else 878 * \c false. 879 */ 880 FLAC_API FLAC__bool FLAC__format_sample_rate_is_valid(unsigned sample_rate); 881 882 /** Tests that a sample rate is valid for the FLAC subset. The subset rules 883 * for valid sample rates are slightly more complex since the rate has to 884 * be expressible completely in the frame header. 885 * 886 * \param sample_rate The sample rate to test for compliance. 887 * \retval FLAC__bool 888 * \c true if the given sample rate conforms to the specification for the 889 * subset, else \c false. 890 */ 891 FLAC_API FLAC__bool FLAC__format_sample_rate_is_subset(unsigned sample_rate); 892 893 /** Check a Vorbis comment entry name to see if it conforms to the Vorbis 894 * comment specification. 895 * 896 * Vorbis comment names must be composed only of characters from 897 * [0x20-0x3C,0x3E-0x7D]. 898 * 899 * \param name A NUL-terminated string to be checked. 900 * \assert 901 * \code name != NULL \endcode 902 * \retval FLAC__bool 903 * \c false if entry name is illegal, else \c true. 904 */ 905 FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_name_is_legal(const char *name); 906 907 /** Check a Vorbis comment entry value to see if it conforms to the Vorbis 908 * comment specification. 909 * 910 * Vorbis comment values must be valid UTF-8 sequences. 911 * 912 * \param value A string to be checked. 913 * \param length A the length of \a value in bytes. May be 914 * \c (unsigned)(-1) to indicate that \a value is a plain 915 * UTF-8 NUL-terminated string. 916 * \assert 917 * \code value != NULL \endcode 918 * \retval FLAC__bool 919 * \c false if entry name is illegal, else \c true. 920 */ 921 FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_value_is_legal(const FLAC__byte *value, unsigned length); 922 923 /** Check a Vorbis comment entry to see if it conforms to the Vorbis 924 * comment specification. 925 * 926 * Vorbis comment entries must be of the form 'name=value', and 'name' and 927 * 'value' must be legal according to 928 * FLAC__format_vorbiscomment_entry_name_is_legal() and 929 * FLAC__format_vorbiscomment_entry_value_is_legal() respectively. 930 * 931 * \param entry An entry to be checked. 932 * \param length The length of \a entry in bytes. 933 * \assert 934 * \code value != NULL \endcode 935 * \retval FLAC__bool 936 * \c false if entry name is illegal, else \c true. 937 */ 938 FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_is_legal(const FLAC__byte *entry, unsigned length); 939 940 /** Check a seek table to see if it conforms to the FLAC specification. 941 * See the format specification for limits on the contents of the 942 * seek table. 943 * 944 * \param seek_table A pointer to a seek table to be checked. 945 * \assert 946 * \code seek_table != NULL \endcode 947 * \retval FLAC__bool 948 * \c false if seek table is illegal, else \c true. 949 */ 950 FLAC_API FLAC__bool FLAC__format_seektable_is_legal(const FLAC__StreamMetadata_SeekTable *seek_table); 951 952 /** Sort a seek table's seek points according to the format specification. 953 * This includes a "unique-ification" step to remove duplicates, i.e. 954 * seek points with identical \a sample_number values. Duplicate seek 955 * points are converted into placeholder points and sorted to the end of 956 * the table. 957 * 958 * \param seek_table A pointer to a seek table to be sorted. 959 * \assert 960 * \code seek_table != NULL \endcode 961 * \retval unsigned 962 * The number of duplicate seek points converted into placeholders. 963 */ 964 FLAC_API unsigned FLAC__format_seektable_sort(FLAC__StreamMetadata_SeekTable *seek_table); 965 966 /** Check a cue sheet to see if it conforms to the FLAC specification. 967 * See the format specification for limits on the contents of the 968 * cue sheet. 969 * 970 * \param cue_sheet A pointer to an existing cue sheet to be checked. 971 * \param check_cd_da_subset If \c true, check CUESHEET against more 972 * stringent requirements for a CD-DA (audio) disc. 973 * \param violation Address of a pointer to a string. If there is a 974 * violation, a pointer to a string explanation of the 975 * violation will be returned here. \a violation may be 976 * \c NULL if you don't need the returned string. Do not 977 * free the returned string; it will always point to static 978 * data. 979 * \assert 980 * \code cue_sheet != NULL \endcode 981 * \retval FLAC__bool 982 * \c false if cue sheet is illegal, else \c true. 983 */ 984 FLAC_API FLAC__bool FLAC__format_cuesheet_is_legal(const FLAC__StreamMetadata_CueSheet *cue_sheet, FLAC__bool check_cd_da_subset, const char **violation); 985 986 /** Check picture data to see if it conforms to the FLAC specification. 987 * See the format specification for limits on the contents of the 988 * PICTURE block. 989 * 990 * \param picture A pointer to existing picture data to be checked. 991 * \param violation Address of a pointer to a string. If there is a 992 * violation, a pointer to a string explanation of the 993 * violation will be returned here. \a violation may be 994 * \c NULL if you don't need the returned string. Do not 995 * free the returned string; it will always point to static 996 * data. 997 * \assert 998 * \code picture != NULL \endcode 999 * \retval FLAC__bool 1000 * \c false if picture data is illegal, else \c true. 1001 */ 1002 FLAC_API FLAC__bool FLAC__format_picture_is_legal(const FLAC__StreamMetadata_Picture *picture, const char **violation); 1003 1004 /* \} */ 1005 1006 #ifdef __cplusplus 1007 } 1008 #endif 1009 1010 #endif 1011