1 /* libFLAC - Free Lossless Audio Codec library
2 * Copyright (C) 2000,2001,2002,2003 Josh Coalson
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
8 * - Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
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.
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.
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.
32 #ifndef FLAC__FORMAT_H
33 #define FLAC__FORMAT_H
42 /** \file include/FLAC/format.h
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.
49 * See the detailed documentation in the
50 * \link flac_format format \endlink module.
53 /** \defgroup flac_format FLAC/format.h: format components
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.
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.
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.
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.
87 Most of the values described in this file are defined by the FLAC
88 format specification. There is nothing to tune here.
91 /** The minimum block size, in samples, permitted by the format. */
92 #define FLAC__MIN_BLOCK_SIZE (16u)
94 /** The maximum block size, in samples, permitted by the format. */
95 #define FLAC__MAX_BLOCK_SIZE (65535u)
97 /** The maximum number of channels permitted by the format. */
98 #define FLAC__MAX_CHANNELS (8u)
100 /** The minimum sample resolution permitted by the format. */
101 #define FLAC__MIN_BITS_PER_SAMPLE (4u)
103 /** The maximum sample resolution permitted by the format. */
104 #define FLAC__MAX_BITS_PER_SAMPLE (32u)
106 /** The maximum sample resolution permitted by libFLAC.
109 * FLAC__MAX_BITS_PER_SAMPLE is the limit of the FLAC format. However,
110 * the reference encoder/decoder is currently limited to 24 bits because
111 * of prevalent 32-bit math, so make sure and use this value when
114 #define FLAC__REFERENCE_CODEC_MAX_BITS_PER_SAMPLE (24u)
116 /** The maximum sample rate permitted by the format. The value is
117 * ((2 ^ 16) - 1) * 10; see <A HREF="../format.html">FLAC format</A>
120 #define FLAC__MAX_SAMPLE_RATE (655350u)
122 /** The maximum LPC order permitted by the format. */
123 #define FLAC__MAX_LPC_ORDER (32u)
125 /** The minimum quantized linear predictor coefficient precision
126 * permitted by the format.
128 #define FLAC__MIN_QLP_COEFF_PRECISION (5u)
130 /** The maximum quantized linear predictor coefficient precision
131 * permitted by the format.
133 #define FLAC__MAX_QLP_COEFF_PRECISION (15u)
135 /** The maximum order of the fixed predictors permitted by the format. */
136 #define FLAC__MAX_FIXED_ORDER (4u)
138 /** The maximum Rice partition order permitted by the format. */
139 #define FLAC__MAX_RICE_PARTITION_ORDER (15u)
141 /** The maximum Rice partition order permitted by the FLAC Subset. */
142 #define FLAC__SUBSET_MAX_RICE_PARTITION_ORDER (8u)
144 /** The version string of the release, stamped onto the libraries and binaries.
147 * This does not correspond to the shared library version number, which
148 * is used to determine binary compatibility.
150 extern FLAC_API const char *FLAC__VERSION_STRING;
152 /** The vendor string inserted by the encoder into the VORBIS_COMMENT block.
153 * This is a nulL-terminated ASCII string; when inserted into the
154 * VORBIS_COMMENT the trailing null is stripped.
156 extern FLAC_API const char *FLAC__VENDOR_STRING;
158 /** The byte string representation of the beginning of a FLAC stream. */
159 extern FLAC_API const FLAC__byte FLAC__STREAM_SYNC_STRING[4]; /* = "fLaC" */
161 /** The 32-bit integer big-endian representation of the beginning of
164 extern FLAC_API const unsigned FLAC__STREAM_SYNC; /* = 0x664C6143 */
166 /** The length of the FLAC signature in bits. */
167 extern FLAC_API const unsigned FLAC__STREAM_SYNC_LEN; /* = 32 bits */
169 /** The length of the FLAC signature in bytes. */
170 #define FLAC__STREAM_SYNC_LENGTH (4u)
173 /*****************************************************************************
175 * Subframe structures
177 *****************************************************************************/
179 /*****************************************************************************/
181 /** An enumeration of the available entropy coding methods. */
183 FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE = 0
184 /**< Residual is coded by partitioning into contexts, each with it's own
186 } FLAC__EntropyCodingMethodType;
188 /** Maps a FLAC__EntropyCodingMethodType to a C string.
190 * Using a FLAC__EntropyCodingMethodType as the index to this array will
191 * give the string equivalent. The contents should not be modified.
193 extern FLAC_API const char * const FLAC__EntropyCodingMethodTypeString[];
196 /** Contents of a Rice partitioned residual
200 unsigned *parameters;
201 /**< The Rice parameters for each context. */
204 /**< Widths for escape-coded partitions. */
206 unsigned capacity_by_order;
207 /**< The capacity of the \a parameters and \a raw_bits arrays
208 * specified as an order, i.e. the number of array elements
209 * allocated is 2 ^ \a capacity_by_order.
211 } FLAC__EntropyCodingMethod_PartitionedRiceContents;
213 /** Header for a Rice partitioned residual. (c.f. <A HREF="../format.html#partitioned_rice">format specification</A>)
218 /**< The partition order, i.e. # of contexts = 2 ^ \a order. */
220 const FLAC__EntropyCodingMethod_PartitionedRiceContents *contents;
221 /**< The context's Rice parameters and/or raw bits. */
223 } FLAC__EntropyCodingMethod_PartitionedRice;
225 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN; /**< == 4 (bits) */
226 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; /**< == 4 (bits) */
227 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN; /**< == 5 (bits) */
229 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;
230 /**< == (1<<FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN)-1 */
232 /** Header for the entropy coding method. (c.f. <A HREF="../format.html#residual">format specification</A>)
235 FLAC__EntropyCodingMethodType type;
237 FLAC__EntropyCodingMethod_PartitionedRice partitioned_rice;
239 } FLAC__EntropyCodingMethod;
241 extern FLAC_API const unsigned FLAC__ENTROPY_CODING_METHOD_TYPE_LEN; /**< == 2 (bits) */
243 /*****************************************************************************/
245 /** An enumeration of the available subframe types. */
247 FLAC__SUBFRAME_TYPE_CONSTANT = 0, /**< constant signal */
248 FLAC__SUBFRAME_TYPE_VERBATIM = 1, /**< uncompressed signal */
249 FLAC__SUBFRAME_TYPE_FIXED = 2, /**< fixed polynomial prediction */
250 FLAC__SUBFRAME_TYPE_LPC = 3 /**< linear prediction */
251 } FLAC__SubframeType;
253 /** Maps a FLAC__SubframeType to a C string.
255 * Using a FLAC__SubframeType as the index to this array will
256 * give the string equivalent. The contents should not be modified.
258 extern FLAC_API const char * const FLAC__SubframeTypeString[];
261 /** CONSTANT subframe. (c.f. <A HREF="../format.html#subframe_constant">format specification</A>)
264 FLAC__int32 value; /**< The constant signal value. */
265 } FLAC__Subframe_Constant;
268 /** VERBATIM subframe. (c.f. <A HREF="../format.html#subframe_verbatim">format specification</A>)
271 const FLAC__int32 *data; /**< A pointer to verbatim signal. */
272 } FLAC__Subframe_Verbatim;
275 /** FIXED subframe. (c.f. <A HREF="../format.html#subframe_fixed">format specification</A>)
278 FLAC__EntropyCodingMethod entropy_coding_method;
279 /**< The residual coding method. */
282 /**< The polynomial order. */
284 FLAC__int32 warmup[FLAC__MAX_FIXED_ORDER];
285 /**< Warmup samples to prime the predictor, length == order. */
287 const FLAC__int32 *residual;
288 /**< The residual signal, length == (blocksize minus order) samples. */
289 } FLAC__Subframe_Fixed;
292 /** LPC subframe. (c.f. <A HREF="../format.html#subframe_lpc">format specification</A>)
295 FLAC__EntropyCodingMethod entropy_coding_method;
296 /**< The residual coding method. */
299 /**< The FIR order. */
301 unsigned qlp_coeff_precision;
302 /**< Quantized FIR filter coefficient precision in bits. */
304 int quantization_level;
305 /**< The qlp coeff shift needed. */
307 FLAC__int32 qlp_coeff[FLAC__MAX_LPC_ORDER];
308 /**< FIR filter coefficients. */
310 FLAC__int32 warmup[FLAC__MAX_LPC_ORDER];
311 /**< Warmup samples to prime the predictor, length == order. */
313 const FLAC__int32 *residual;
314 /**< The residual signal, length == (blocksize minus order) samples. */
315 } FLAC__Subframe_LPC;
317 extern FLAC_API const unsigned FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN; /**< == 4 (bits) */
318 extern FLAC_API const unsigned FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN; /**< == 5 (bits) */
321 /** FLAC subframe structure. (c.f. <A HREF="../format.html#subframe">format specification</A>)
324 FLAC__SubframeType type;
326 FLAC__Subframe_Constant constant;
327 FLAC__Subframe_Fixed fixed;
328 FLAC__Subframe_LPC lpc;
329 FLAC__Subframe_Verbatim verbatim;
331 unsigned wasted_bits;
334 extern FLAC_API const unsigned FLAC__SUBFRAME_ZERO_PAD_LEN; /**< == 1 (bit) */
335 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_LEN; /**< == 6 (bits) */
336 extern FLAC_API const unsigned FLAC__SUBFRAME_WASTED_BITS_FLAG_LEN; /**< == 1 (bit) */
338 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_CONSTANT_BYTE_ALIGNED_MASK; /* = 0x00 */
339 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_VERBATIM_BYTE_ALIGNED_MASK; /* = 0x02 */
340 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_FIXED_BYTE_ALIGNED_MASK; /* = 0x10 */
341 extern FLAC_API const unsigned FLAC__SUBFRAME_TYPE_LPC_BYTE_ALIGNED_MASK; /* = 0x40 */
343 /*****************************************************************************/
346 /*****************************************************************************
350 *****************************************************************************/
352 /** An enumeration of the available channel assignments. */
354 FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT = 0, /**< independent channels */
355 FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE = 1, /**< left+side stereo */
356 FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE = 2, /**< right+side stereo */
357 FLAC__CHANNEL_ASSIGNMENT_MID_SIDE = 3 /**< mid+side stereo */
358 } FLAC__ChannelAssignment;
360 /** Maps a FLAC__ChannelAssignment to a C string.
362 * Using a FLAC__ChannelAssignment as the index to this array will
363 * give the string equivalent. The contents should not be modified.
365 extern FLAC_API const char * const FLAC__ChannelAssignmentString[];
367 /** An enumeration of the possible frame numbering methods. */
369 FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER, /**< number contains the frame number */
370 FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER /**< number contains the sample number of first sample in frame */
371 } FLAC__FrameNumberType;
373 /** Maps a FLAC__FrameNumberType to a C string.
375 * Using a FLAC__FrameNumberType as the index to this array will
376 * give the string equivalent. The contents should not be modified.
378 extern FLAC_API const char * const FLAC__FrameNumberTypeString[];
381 /** FLAC frame header structure. (c.f. <A HREF="../format.html#frame_header">format specification</A>)
385 /**< The number of samples per subframe. */
387 unsigned sample_rate;
388 /**< The sample rate in Hz. */
391 /**< The number of channels (== number of subframes). */
393 FLAC__ChannelAssignment channel_assignment;
394 /**< The channel assignment for the frame. */
396 unsigned bits_per_sample;
397 /**< The sample resolution. */
399 FLAC__FrameNumberType number_type;
400 /**< The numbering scheme used for the frame. */
403 FLAC__uint32 frame_number;
404 FLAC__uint64 sample_number;
406 /**< The frame number or sample number of first sample in frame;
407 * use the \a number_type value to determine which to use. */
410 /**< CRC-8 (polynomial = x^8 + x^2 + x^1 + x^0, initialized with 0)
411 * of the raw frame header bytes, meaning everything before the CRC byte
412 * including the sync code.
416 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SYNC; /**< == 0x3ffe; the frame header sync code */
417 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SYNC_LEN; /**< == 14 (bits) */
418 extern FLAC_API const unsigned FLAC__FRAME_HEADER_RESERVED_LEN; /**< == 2 (bits) */
419 extern FLAC_API const unsigned FLAC__FRAME_HEADER_BLOCK_SIZE_LEN; /**< == 4 (bits) */
420 extern FLAC_API const unsigned FLAC__FRAME_HEADER_SAMPLE_RATE_LEN; /**< == 4 (bits) */
421 extern FLAC_API const unsigned FLAC__FRAME_HEADER_CHANNEL_ASSIGNMENT_LEN; /**< == 4 (bits) */
422 extern FLAC_API const unsigned FLAC__FRAME_HEADER_BITS_PER_SAMPLE_LEN; /**< == 3 (bits) */
423 extern FLAC_API const unsigned FLAC__FRAME_HEADER_ZERO_PAD_LEN; /**< == 1 (bit) */
424 extern FLAC_API const unsigned FLAC__FRAME_HEADER_CRC_LEN; /**< == 8 (bits) */
427 /** FLAC frame footer structure. (c.f. <A HREF="../format.html#frame_footer">format specification</A>)
431 /**< CRC-16 (polynomial = x^16 + x^15 + x^2 + x^0, initialized with
432 * 0) of the bytes before the crc, back to and including the frame header
437 extern FLAC_API const unsigned FLAC__FRAME_FOOTER_CRC_LEN; /**< == 16 (bits) */
440 /** FLAC frame structure. (c.f. <A HREF="../format.html#frame">format specification</A>)
443 FLAC__FrameHeader header;
444 FLAC__Subframe subframes[FLAC__MAX_CHANNELS];
445 FLAC__FrameFooter footer;
448 /*****************************************************************************/
451 /*****************************************************************************
453 * Meta-data structures
455 *****************************************************************************/
457 /** An enumeration of the available metadata block types. */
460 FLAC__METADATA_TYPE_STREAMINFO = 0,
461 /**< <A HREF="../format.html#metadata_block_streaminfo">STREAMINFO</A> block */
463 FLAC__METADATA_TYPE_PADDING = 1,
464 /**< <A HREF="../format.html#metadata_block_padding">PADDING</A> block */
466 FLAC__METADATA_TYPE_APPLICATION = 2,
467 /**< <A HREF="../format.html#metadata_block_application">APPLICATION</A> block */
469 FLAC__METADATA_TYPE_SEEKTABLE = 3,
470 /**< <A HREF="../format.html#metadata_block_seektable">SEEKTABLE</A> block */
472 FLAC__METADATA_TYPE_VORBIS_COMMENT = 4,
473 /**< <A HREF="../format.html#metadata_block_vorbis_comment">VORBISCOMMENT</A> block */
475 FLAC__METADATA_TYPE_CUESHEET = 5,
476 /**< <A HREF="../format.html#metadata_block_cuesheet">CUESHEET</A> block */
478 FLAC__METADATA_TYPE_UNDEFINED = 6
479 /**< marker to denote beginning of undefined type range; this number will increase as new metadata types are added */
481 } FLAC__MetadataType;
483 /** Maps a FLAC__MetadataType to a C string.
485 * Using a FLAC__MetadataType as the index to this array will
486 * give the string equivalent. The contents should not be modified.
488 extern FLAC_API const char * const FLAC__MetadataTypeString[];
491 /** FLAC STREAMINFO structure. (c.f. <A HREF="../format.html#metadata_block_streaminfo">format specification</A>)
494 unsigned min_blocksize, max_blocksize;
495 unsigned min_framesize, max_framesize;
496 unsigned sample_rate;
498 unsigned bits_per_sample;
499 FLAC__uint64 total_samples;
500 FLAC__byte md5sum[16];
501 } FLAC__StreamMetadata_StreamInfo;
503 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN; /**< == 16 (bits) */
504 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN; /**< == 16 (bits) */
505 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN; /**< == 24 (bits) */
506 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN; /**< == 24 (bits) */
507 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN; /**< == 20 (bits) */
508 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN; /**< == 3 (bits) */
509 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN; /**< == 5 (bits) */
510 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN; /**< == 36 (bits) */
511 extern FLAC_API const unsigned FLAC__STREAM_METADATA_STREAMINFO_MD5SUM_LEN; /**< == 128 (bits) */
513 /** The total stream length of the STREAMINFO block in bytes. */
514 #define FLAC__STREAM_METADATA_STREAMINFO_LENGTH (34u)
516 /** FLAC PADDING structure. (c.f. <A HREF="../format.html#metadata_block_padding">format specification</A>)
520 /**< Conceptually this is an empty struct since we don't store the
521 * padding bytes. Empty structs are not allowed by some C compilers,
524 } FLAC__StreamMetadata_Padding;
527 /** FLAC APPLICATION structure. (c.f. <A HREF="../format.html#metadata_block_application">format specification</A>)
532 } FLAC__StreamMetadata_Application;
534 extern FLAC_API const unsigned FLAC__STREAM_METADATA_APPLICATION_ID_LEN; /**< == 32 (bits) */
536 /** SeekPoint structure used in SEEKTABLE blocks. (c.f. <A HREF="../format.html#seekpoint">format specification</A>)
539 FLAC__uint64 sample_number;
540 /**< The sample number of the target frame. */
542 FLAC__uint64 stream_offset;
543 /**< The offset, in bytes, of the target frame with respect to
544 * beginning of the first frame. */
546 unsigned frame_samples;
547 /**< The number of samples in the target frame. */
548 } FLAC__StreamMetadata_SeekPoint;
550 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN; /**< == 64 (bits) */
551 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN; /**< == 64 (bits) */
552 extern FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN; /**< == 16 (bits) */
554 /** The total stream length of a seek point in bytes. */
555 #define FLAC__STREAM_METADATA_SEEKPOINT_LENGTH (18u)
557 /** The value used in the \a sample_number field of
558 * FLAC__StreamMetadataSeekPoint used to indicate a placeholder
559 * point (== 0xffffffffffffffff).
561 extern FLAC_API const FLAC__uint64 FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER;
564 /** FLAC SEEKTABLE structure. (c.f. <A HREF="../format.html#metadata_block_seektable">format specification</A>)
566 * \note From the format specification:
567 * - The seek points must be sorted by ascending sample number.
568 * - Each seek point's sample number must be the first sample of the
570 * - Each seek point's sample number must be unique within the table.
571 * - Existence of a SEEKTABLE block implies a correct setting of
572 * total_samples in the stream_info block.
573 * - Behavior is undefined when more than one SEEKTABLE block is
574 * present in a stream.
578 FLAC__StreamMetadata_SeekPoint *points;
579 } FLAC__StreamMetadata_SeekTable;
582 /** Vorbis comment entry structure used in VORBIS_COMMENT blocks. (c.f. <A HREF="../format.html#metadata_block_vorbis_comment">format specification</A>)
587 } FLAC__StreamMetadata_VorbisComment_Entry;
589 extern FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN; /**< == 32 (bits) */
592 /** FLAC VORBIS_COMMENT structure. (c.f. <A HREF="../format.html#metadata_block_vorbis_comment">format specification</A>)
595 FLAC__StreamMetadata_VorbisComment_Entry vendor_string;
596 FLAC__uint32 num_comments;
597 FLAC__StreamMetadata_VorbisComment_Entry *comments;
598 } FLAC__StreamMetadata_VorbisComment;
600 extern FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN; /**< == 32 (bits) */
603 /** FLAC CUESHEET track index structure. (See the
604 * <A HREF="../format.html#cuesheet_track_index">format specification</A> for
605 * the full description of each field.)
609 /**< Offset in samples, relative to the track offset, of the index
614 /**< The index point number. */
615 } FLAC__StreamMetadata_CueSheet_Index;
617 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN; /**< == 64 (bits) */
618 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN; /**< == 8 (bits) */
619 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN; /**< == 3*8 (bits) */
622 /** FLAC CUESHEET track structure. (See the
623 * <A HREF="../format.html#cuesheet_track">format specification</A> for
624 * the full description of each field.)
628 /**< Track offset in samples, relative to the beginning of the FLAC audio stream. */
631 /**< The track number. */
634 /**< Track ISRC. This is a 12-digit alphanumeric code plus a trailing '\0' */
637 /**< The track type: 0 for audio, 1 for non-audio. */
639 unsigned pre_emphasis:1;
640 /**< The pre-emphasis flag: 0 for no pre-emphasis, 1 for pre-emphasis. */
642 FLAC__byte num_indices;
643 /**< The number of track index points. */
645 FLAC__StreamMetadata_CueSheet_Index *indices;
646 /**< NULL if num_indices == 0, else pointer to array of index points. */
648 } FLAC__StreamMetadata_CueSheet_Track;
650 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN; /**< == 64 (bits) */
651 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN; /**< == 8 (bits) */
652 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN; /**< == 12*8 (bits) */
653 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN; /**< == 1 (bit) */
654 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN; /**< == 1 (bit) */
655 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN; /**< == 6+13*8 (bits) */
656 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN; /**< == 8 (bits) */
659 /** FLAC CUESHEET structure. (See the
660 * <A HREF="../format.html#metadata_block_cuesheet">format specification</A>
661 * for the full description of each field.)
664 char media_catalog_number[129];
665 /**< Media catalog number, in ASCII printable characters 0x20-0x7e. In
666 * general, the media catalog number may be 0 to 128 bytes long; any
667 * unused characters should be right-padded with NUL characters.
670 FLAC__uint64 lead_in;
671 /**< The number of lead-in samples. */
674 /**< \c true if CUESHEET corresponds to a Compact Disc, else \c false */
677 /**< The number of tracks. */
679 FLAC__StreamMetadata_CueSheet_Track *tracks;
680 /**< NULL if num_tracks == 0, else pointer to array of tracks. */
682 } FLAC__StreamMetadata_CueSheet;
684 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN; /**< == 128*8 (bits) */
685 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN; /**< == 64 (bits) */
686 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN; /**< == 1 (bit) */
687 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN; /**< == 7+258*8 (bits) */
688 extern FLAC_API const unsigned FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN; /**< == 8 (bits) */
691 /** Structure that is used when a metadata block of unknown type is loaded.
692 * The contents are opaque. The structure is used only internally to
693 * correctly handle unknown metadata.
697 } FLAC__StreamMetadata_Unknown;
700 /** FLAC metadata block structure. (c.f. <A HREF="../format.html#metadata_block">format specification</A>)
703 FLAC__MetadataType type;
704 /**< The type of the metadata block; used determine which member of the
705 * \a data union to dereference. If type >= FLAC__METADATA_TYPE_UNDEFINED
706 * then \a data.unknown must be used. */
709 /**< \c true if this metadata block is the last, else \a false */
712 /**< Length, in bytes, of the block data as it appears in the stream. */
715 FLAC__StreamMetadata_StreamInfo stream_info;
716 FLAC__StreamMetadata_Padding padding;
717 FLAC__StreamMetadata_Application application;
718 FLAC__StreamMetadata_SeekTable seek_table;
719 FLAC__StreamMetadata_VorbisComment vorbis_comment;
720 FLAC__StreamMetadata_CueSheet cue_sheet;
721 FLAC__StreamMetadata_Unknown unknown;
723 /**< Polymorphic block data; use the \a type value to determine which
725 } FLAC__StreamMetadata;
727 extern FLAC_API const unsigned FLAC__STREAM_METADATA_IS_LAST_LEN; /**< == 1 (bit) */
728 extern FLAC_API const unsigned FLAC__STREAM_METADATA_TYPE_LEN; /**< == 7 (bits) */
729 extern FLAC_API const unsigned FLAC__STREAM_METADATA_LENGTH_LEN; /**< == 24 (bits) */
731 /** The total stream length of a metadata block header in bytes. */
732 #define FLAC__STREAM_METADATA_HEADER_LENGTH (4u)
734 /*****************************************************************************/
737 /*****************************************************************************
741 *****************************************************************************/
743 /* @@@@ add to unit tests; it is already indirectly tested by the metadata_object tests */
744 /** Tests that a sample rate is valid for FLAC. Since the rules for valid
745 * sample rates are slightly complex, they are encapsulated in this function.
747 * \param sample_rate The sample rate to test for compliance.
749 * \c true if the given sample rate conforms to the specification, else
752 FLAC_API FLAC__bool FLAC__format_sample_rate_is_valid(unsigned sample_rate);
754 /* @@@@ add to unit tests; it is already indirectly tested by the metadata_object tests */
755 /** Check a seek table to see if it conforms to the FLAC specification.
756 * See the format specification for limits on the contents of the
759 * \param seek_table A pointer to a seek table to be checked.
761 * \code seek_table != NULL \endcode
763 * \c false if seek table is illegal, else \c true.
765 FLAC_API FLAC__bool FLAC__format_seektable_is_legal(const FLAC__StreamMetadata_SeekTable *seek_table);
767 /* @@@@ add to unit tests; it is already indirectly tested by the metadata_object tests */
768 /** Sort a seek table's seek points according to the format specification.
769 * This includes a "unique-ification" step to remove duplicates, i.e.
770 * seek points with identical \a sample_number values. Duplicate seek
771 * points are converted into placeholder points and sorted to the end of
774 * \param seek_table A pointer to a seek table to be sorted.
776 * \code seek_table != NULL \endcode
778 * The number of duplicate seek points converted into placeholders.
780 FLAC_API unsigned FLAC__format_seektable_sort(FLAC__StreamMetadata_SeekTable *seek_table);
782 /* @@@@ add to unit tests; it is already indirectly tested by the metadata_object tests */
783 /** Check a cue sheet to see if it conforms to the FLAC specification.
784 * See the format specification for limits on the contents of the
787 * \param cue_sheet A pointer to an existing cue sheet to be checked.
788 * \param check_cd_da_subset If \c true, check CUESHEET against more
789 * stringent requirements for a CD-DA (audio) disc.
790 * \param violation Address of a pointer to a string. If there is a
791 * violation, a pointer to a string explanation of the
792 * violation will be returned here. \a violation may be
793 * \c NULL if you don't need the returned string. Do not
794 * free the returned string; it will always point to static
797 * \code cue_sheet != NULL \endcode
799 * \c false if cue sheet is illegal, else \c true.
801 FLAC_API FLAC__bool FLAC__format_cuesheet_is_legal(const FLAC__StreamMetadata_CueSheet *cue_sheet, FLAC__bool check_cd_da_subset, const char **violation);