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Diffstat (limited to 'include/FLAC/format.h')
| -rw-r--r-- | include/FLAC/format.h | 1032 |
1 files changed, 1032 insertions, 0 deletions
diff --git a/include/FLAC/format.h b/include/FLAC/format.h new file mode 100644 index 0000000..ef7c8b2 --- /dev/null +++ b/include/FLAC/format.h @@ -0,0 +1,1032 @@ +/* libFLAC - Free Lossless Audio Codec library + * Copyright (C) 2000-2009 Josh Coalson + * Copyright (C) 2011-2023 Xiph.Org Foundation + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * - Neither the name of the Xiph.org Foundation nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef FLAC__FORMAT_H +#define FLAC__FORMAT_H + +#include "export.h" +#include "ordinals.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/** \file include/FLAC/format.h + * + * \brief + * This module contains structure definitions for the representation + * of FLAC format components in memory. These are the basic + * structures used by the rest of the interfaces. + * + * See the detailed documentation in the + * \link flac_format format \endlink module. + */ + +/** \defgroup flac_format FLAC/format.h: format components + * \ingroup flac + * + * \brief + * This module contains structure definitions for the representation + * of FLAC format components in memory. These are the basic + * structures used by the rest of the interfaces. + * + * First, you should be familiar with the + * <A HREF="https://xiph.org/flac/format.html">FLAC format</A>. Many of the values here + * follow directly from the specification. As a user of libFLAC, the + * interesting parts really are the structures that describe the frame + * header and metadata blocks. + * + * The format structures here are very primitive, designed to store + * information in an efficient way. Reading information from the + * structures is easy but creating or modifying them directly is + * more complex. For the most part, as a user of a library, editing + * is not necessary; however, for metadata blocks it is, so there are + * convenience functions provided in the \link flac_metadata metadata + * module \endlink to simplify the manipulation of metadata blocks. + * + * \note + * It's not the best convention, but symbols ending in _LEN are in bits + * and _LENGTH are in bytes. _LENGTH symbols are \#defines instead of + * global variables because they are usually used when declaring byte + * arrays and some compilers require compile-time knowledge of array + * sizes when declared on the stack. + * + * \{ + */ + + +/* + Most of the values described in this file are defined by the FLAC + format specification. There is nothing to tune here. +*/ + +/** The largest legal metadata type code. */ +#define FLAC__MAX_METADATA_TYPE_CODE (126u) + +/** The minimum block size, in samples, permitted by the format. */ +#define FLAC__MIN_BLOCK_SIZE (16u) + +/** The maximum block size, in samples, permitted by the format. */ +#define FLAC__MAX_BLOCK_SIZE (65535u) + +/** The maximum block size, in samples, permitted by the FLAC subset for + * sample rates up to 48kHz. */ +#define FLAC__SUBSET_MAX_BLOCK_SIZE_48000HZ (4608u) + +/** The maximum number of channels permitted by the format. */ +#define FLAC__MAX_CHANNELS (8u) + +/** The minimum sample resolution permitted by the format. */ +#define FLAC__MIN_BITS_PER_SAMPLE (4u) + +/** The maximum sample resolution permitted by the format. */ +#define FLAC__MAX_BITS_PER_SAMPLE (32u) + +/** The maximum sample resolution permitted by libFLAC. + * + * FLAC__MAX_BITS_PER_SAMPLE is the limit of the FLAC format. However, + * the reference encoder/decoder used to be limited to 24 bits. This + * value was used to signal that limit. + */ +#define FLAC__REFERENCE_CODEC_MAX_BITS_PER_SAMPLE (32u) + +/** The maximum sample rate permitted by the format. The value is + * ((2 ^ 20) - 1) + */ +#define FLAC__MAX_SAMPLE_RATE (1048575u) + +/** The maximum LPC order permitted by the format. */ +#define FLAC__MAX_LPC_ORDER (32u) + +/** The maximum LPC order permitted by the FLAC subset for sample rates + * up to 48kHz. */ +#define FLAC__SUBSET_MAX_LPC_ORDER_48000HZ (12u) + +/** The minimum quantized linear predictor coefficient precision + * permitted by the format. + */ +#define FLAC__MIN_QLP_COEFF_PRECISION (5u) + +/** The maximum quantized linear predictor coefficient precision + * permitted by the format. + */ +#define FLAC__MAX_QLP_COEFF_PRECISION (15u) + +/** The maximum order of the fixed predictors permitted by the format. */ +#define FLAC__MAX_FIXED_ORDER (4u) + +/** The maximum Rice partition order permitted by the format. */ +#define FLAC__MAX_RICE_PARTITION_ORDER (15u) + +/** The maximum Rice partition order permitted by the FLAC Subset. */ +#define FLAC__SUBSET_MAX_RICE_PARTITION_ORDER (8u) + +/** The version string of the release, stamped onto the libraries and binaries. + * + * \note + * This does not correspond to the shared library version number, which + * is used to determine binary compatibility. + */ +extern FLAC_API const char *FLAC__VERSION_STRING; + +/** The vendor string inserted by the encoder into the VORBIS_COMMENT block. + * This is a NUL-terminated ASCII string; when inserted into the + * VORBIS_COMMENT the trailing null is stripped. + */ +extern FLAC_API const char *FLAC__VENDOR_STRING; + +/** The byte string representation of the beginning of a FLAC stream. */ +extern FLAC_API const FLAC__byte FLAC__STREAM_SYNC_STRING[4]; /* = "fLaC" */ + +/** The 32-bit integer big-endian representation of the beginning of + * a FLAC stream. + */ +extern FLAC_API const uint32_t FLAC__STREAM_SYNC; /* = 0x664C6143 */ + +/** The length of the FLAC signature in bits. */ +extern FLAC_API const uint32_t FLAC__STREAM_SYNC_LEN; /* = 32 bits */ + +/** The length of the FLAC signature in bytes. */ +#define FLAC__STREAM_SYNC_LENGTH (4u) + + +/***************************************************************************** + * + * Subframe structures + * + *****************************************************************************/ + +/*****************************************************************************/ + +/** An enumeration of the available entropy coding methods. */ +typedef enum { + FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE = 0, + /**< Residual is coded by partitioning into contexts, each with it's own + * 4-bit Rice parameter. */ + + FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2 = 1 + /**< Residual is coded by partitioning into contexts, each with it's own + * 5-bit Rice parameter. */ +} FLAC__EntropyCodingMethodType; + +/** Maps a FLAC__EntropyCodingMethodType to a C string. + * + * Using a FLAC__EntropyCodingMethodType as the index to this array will + * give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__EntropyCodingMethodTypeString[]; + + +/** Contents of a Rice partitioned residual + */ +typedef struct { + + uint32_t *parameters; + /**< The Rice parameters for each context. */ + + uint32_t *raw_bits; + /**< Widths for escape-coded partitions. Will be non-zero for escaped + * partitions and zero for unescaped partitions. + */ + + uint32_t capacity_by_order; + /**< The capacity of the \a parameters and \a raw_bits arrays + * specified as an order, i.e. the number of array elements + * allocated is 2 ^ \a capacity_by_order. + */ +} FLAC__EntropyCodingMethod_PartitionedRiceContents; + +/** Header for a Rice partitioned residual. (c.f. <A HREF="https://xiph.org/flac/format.html#partitioned_rice">format specification</A>) + */ +typedef struct { + + uint32_t order; + /**< The partition order, i.e. # of contexts = 2 ^ \a order. */ + + const FLAC__EntropyCodingMethod_PartitionedRiceContents *contents; + /**< The context's Rice parameters and/or raw bits. */ + +} FLAC__EntropyCodingMethod_PartitionedRice; + +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN; /**< == 5 (bits) */ +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN; /**< == 5 (bits) */ + +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER; +/**< == (1<<FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN)-1 */ +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER; +/**< == (1<<FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN)-1 */ + +/** Header for the entropy coding method. (c.f. <A HREF="https://xiph.org/flac/format.html#residual">format specification</A>) + */ +typedef struct { + FLAC__EntropyCodingMethodType type; + union { + FLAC__EntropyCodingMethod_PartitionedRice partitioned_rice; + } data; +} FLAC__EntropyCodingMethod; + +extern FLAC_API const uint32_t FLAC__ENTROPY_CODING_METHOD_TYPE_LEN; /**< == 2 (bits) */ + +/*****************************************************************************/ + +/** An enumeration of the available subframe types. */ +typedef enum { + FLAC__SUBFRAME_TYPE_CONSTANT = 0, /**< constant signal */ + FLAC__SUBFRAME_TYPE_VERBATIM = 1, /**< uncompressed signal */ + FLAC__SUBFRAME_TYPE_FIXED = 2, /**< fixed polynomial prediction */ + FLAC__SUBFRAME_TYPE_LPC = 3 /**< linear prediction */ +} FLAC__SubframeType; + +/** Maps a FLAC__SubframeType to a C string. + * + * Using a FLAC__SubframeType as the index to this array will + * give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__SubframeTypeString[]; + + +/** CONSTANT subframe. (c.f. <A HREF="https://xiph.org/flac/format.html#subframe_constant">format specification</A>) + */ +typedef struct { + FLAC__int64 value; /**< The constant signal value. */ +} FLAC__Subframe_Constant; + +/** An enumeration of the possible verbatim subframe data types. */ +typedef enum { + FLAC__VERBATIM_SUBFRAME_DATA_TYPE_INT32, /**< verbatim subframe has 32-bit int */ + FLAC__VERBATIM_SUBFRAME_DATA_TYPE_INT64 /**< verbatim subframe has 64-bit int */ +} FLAC__VerbatimSubframeDataType; + + +/** VERBATIM subframe. (c.f. <A HREF="https://xiph.org/flac/format.html#subframe_verbatim">format specification</A>) + */ +typedef struct { + union { + const FLAC__int32 *int32; /**< A FLAC__int32 pointer to verbatim signal. */ + const FLAC__int64 *int64; /**< A FLAC__int64 pointer to verbatim signal. */ + } data; + FLAC__VerbatimSubframeDataType data_type; +} FLAC__Subframe_Verbatim; + + +/** FIXED subframe. (c.f. <A HREF="https://xiph.org/flac/format.html#subframe_fixed">format specification</A>) + */ +typedef struct { + FLAC__EntropyCodingMethod entropy_coding_method; + /**< The residual coding method. */ + + uint32_t order; + /**< The polynomial order. */ + + FLAC__int64 warmup[FLAC__MAX_FIXED_ORDER]; + /**< Warmup samples to prime the predictor, length == order. */ + + const FLAC__int32 *residual; + /**< The residual signal, length == (blocksize minus order) samples. */ +} FLAC__Subframe_Fixed; + + +/** LPC subframe. (c.f. <A HREF="https://xiph.org/flac/format.html#subframe_lpc">format specification</A>) + */ +typedef struct { + FLAC__EntropyCodingMethod entropy_coding_method; + /**< The residual coding method. */ + + uint32_t order; + /**< The FIR order. */ + + uint32_t qlp_coeff_precision; + /**< Quantized FIR filter coefficient precision in bits. */ + + int quantization_level; + /**< The qlp coeff shift needed. */ + + FLAC__int32 qlp_coeff[FLAC__MAX_LPC_ORDER]; + /**< FIR filter coefficients. */ + + FLAC__int64 warmup[FLAC__MAX_LPC_ORDER]; + /**< Warmup samples to prime the predictor, length == order. */ + + const FLAC__int32 *residual; + /**< The residual signal, length == (blocksize minus order) samples. */ +} FLAC__Subframe_LPC; + +extern FLAC_API const uint32_t FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN; /**< == 5 (bits) */ + + +/** FLAC subframe structure. (c.f. <A HREF="https://xiph.org/flac/format.html#subframe">format specification</A>) + */ +typedef struct { + FLAC__SubframeType type; + union { + FLAC__Subframe_Constant constant; + FLAC__Subframe_Fixed fixed; + FLAC__Subframe_LPC lpc; + FLAC__Subframe_Verbatim verbatim; + } data; + uint32_t wasted_bits; +} FLAC__Subframe; + +/** == 1 (bit) + * + * This used to be a zero-padding bit (hence the name + * FLAC__SUBFRAME_ZERO_PAD_LEN) but is now a reserved bit. It still has a + * mandatory value of \c 0 but in the future may take on the value \c 0 or \c 1 + * to mean something else. + */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_ZERO_PAD_LEN; +extern FLAC_API const uint32_t FLAC__SUBFRAME_TYPE_LEN; /**< == 6 (bits) */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_WASTED_BITS_FLAG_LEN; /**< == 1 (bit) */ + +extern FLAC_API const uint32_t FLAC__SUBFRAME_TYPE_CONSTANT_BYTE_ALIGNED_MASK; /**< = 0x00 */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_TYPE_VERBATIM_BYTE_ALIGNED_MASK; /**< = 0x02 */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_TYPE_FIXED_BYTE_ALIGNED_MASK; /**< = 0x10 */ +extern FLAC_API const uint32_t FLAC__SUBFRAME_TYPE_LPC_BYTE_ALIGNED_MASK; /**< = 0x40 */ + +/*****************************************************************************/ + + +/***************************************************************************** + * + * Frame structures + * + *****************************************************************************/ + +/** An enumeration of the available channel assignments. */ +typedef enum { + FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT = 0, /**< independent channels */ + FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE = 1, /**< left+side stereo */ + FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE = 2, /**< right+side stereo */ + FLAC__CHANNEL_ASSIGNMENT_MID_SIDE = 3 /**< mid+side stereo */ +} FLAC__ChannelAssignment; + +/** Maps a FLAC__ChannelAssignment to a C string. + * + * Using a FLAC__ChannelAssignment as the index to this array will + * give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__ChannelAssignmentString[]; + +/** An enumeration of the possible frame numbering methods. */ +typedef enum { + FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER, /**< number contains the frame number */ + FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER /**< number contains the sample number of first sample in frame */ +} FLAC__FrameNumberType; + +/** Maps a FLAC__FrameNumberType to a C string. + * + * Using a FLAC__FrameNumberType as the index to this array will + * give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__FrameNumberTypeString[]; + + +/** FLAC frame header structure. (c.f. <A HREF="https://xiph.org/flac/format.html#frame_header">format specification</A>) + */ +typedef struct { + uint32_t blocksize; + /**< The number of samples per subframe. */ + + uint32_t sample_rate; + /**< The sample rate in Hz. */ + + uint32_t channels; + /**< The number of channels (== number of subframes). */ + + FLAC__ChannelAssignment channel_assignment; + /**< The channel assignment for the frame. */ + + uint32_t bits_per_sample; + /**< The sample resolution. */ + + FLAC__FrameNumberType number_type; + /**< The numbering scheme used for the frame. As a convenience, the + * decoder will always convert a frame number to a sample number because + * the rules are complex. */ + + union { + FLAC__uint32 frame_number; + FLAC__uint64 sample_number; + } number; + /**< The frame number or sample number of first sample in frame; + * use the \a number_type value to determine which to use. */ + + FLAC__uint8 crc; + /**< CRC-8 (polynomial = x^8 + x^2 + x^1 + x^0, initialized with 0) + * of the raw frame header bytes, meaning everything before the CRC byte + * including the sync code. + */ +} FLAC__FrameHeader; + +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_SYNC; /**< == 0x3ffe; the frame header sync code */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_SYNC_LEN; /**< == 14 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_RESERVED_LEN; /**< == 1 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_BLOCKING_STRATEGY_LEN; /**< == 1 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_BLOCK_SIZE_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_SAMPLE_RATE_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_CHANNEL_ASSIGNMENT_LEN; /**< == 4 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_BITS_PER_SAMPLE_LEN; /**< == 3 (bits) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_ZERO_PAD_LEN; /**< == 1 (bit) */ +extern FLAC_API const uint32_t FLAC__FRAME_HEADER_CRC_LEN; /**< == 8 (bits) */ + + +/** FLAC frame footer structure. (c.f. <A HREF="https://xiph.org/flac/format.html#frame_footer">format specification</A>) + */ +typedef struct { + FLAC__uint16 crc; + /**< CRC-16 (polynomial = x^16 + x^15 + x^2 + x^0, initialized with + * 0) of the bytes before the crc, back to and including the frame header + * sync code. + */ +} FLAC__FrameFooter; + +extern FLAC_API const uint32_t FLAC__FRAME_FOOTER_CRC_LEN; /**< == 16 (bits) */ + + +/** FLAC frame structure. (c.f. <A HREF="https://xiph.org/flac/format.html#frame">format specification</A>) + */ +typedef struct { + FLAC__FrameHeader header; + FLAC__Subframe subframes[FLAC__MAX_CHANNELS]; + FLAC__FrameFooter footer; +} FLAC__Frame; + +/*****************************************************************************/ + + +/***************************************************************************** + * + * Meta-data structures + * + *****************************************************************************/ + +/** An enumeration of the available metadata block types. */ +typedef enum { + + FLAC__METADATA_TYPE_STREAMINFO = 0, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_streaminfo">STREAMINFO</A> block */ + + FLAC__METADATA_TYPE_PADDING = 1, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_padding">PADDING</A> block */ + + FLAC__METADATA_TYPE_APPLICATION = 2, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_application">APPLICATION</A> block */ + + FLAC__METADATA_TYPE_SEEKTABLE = 3, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_seektable">SEEKTABLE</A> block */ + + FLAC__METADATA_TYPE_VORBIS_COMMENT = 4, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_vorbis_comment">VORBISCOMMENT</A> block (a.k.a. FLAC tags) */ + + FLAC__METADATA_TYPE_CUESHEET = 5, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_cuesheet">CUESHEET</A> block */ + + FLAC__METADATA_TYPE_PICTURE = 6, + /**< <A HREF="https://xiph.org/flac/format.html#metadata_block_picture">PICTURE</A> block */ + + FLAC__METADATA_TYPE_UNDEFINED = 7, + /**< marker to denote beginning of undefined type range; this number will increase as new metadata types are added */ + + FLAC__MAX_METADATA_TYPE = FLAC__MAX_METADATA_TYPE_CODE, + /**< No type will ever be greater than this. There is not enough room in the protocol block. */ +} FLAC__MetadataType; + +/** Maps a FLAC__MetadataType to a C string. + * + * Using a FLAC__MetadataType as the index to this array will + * give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__MetadataTypeString[]; + + +/** FLAC STREAMINFO structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_streaminfo">format specification</A>) + */ +typedef struct { + uint32_t min_blocksize, max_blocksize; + uint32_t min_framesize, max_framesize; + uint32_t sample_rate; + uint32_t channels; + uint32_t bits_per_sample; + FLAC__uint64 total_samples; + FLAC__byte md5sum[16]; +} FLAC__StreamMetadata_StreamInfo; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN; /**< == 16 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN; /**< == 16 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN; /**< == 24 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN; /**< == 24 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN; /**< == 20 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN; /**< == 3 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN; /**< == 5 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN; /**< == 36 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_STREAMINFO_MD5SUM_LEN; /**< == 128 (bits) */ + +/** The total stream length of the STREAMINFO block in bytes. */ +#define FLAC__STREAM_METADATA_STREAMINFO_LENGTH (34u) + +/** FLAC PADDING structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_padding">format specification</A>) + */ +typedef struct { + int dummy; + /**< Conceptually this is an empty struct since we don't store the + * padding bytes. Empty structs are not allowed by some C compilers, + * hence the dummy. + */ +} FLAC__StreamMetadata_Padding; + + +/** FLAC APPLICATION structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_application">format specification</A>) + */ +typedef struct { + FLAC__byte id[4]; + FLAC__byte *data; +} FLAC__StreamMetadata_Application; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_APPLICATION_ID_LEN; /**< == 32 (bits) */ + +/** SeekPoint structure used in SEEKTABLE blocks. (c.f. <A HREF="https://xiph.org/flac/format.html#seekpoint">format specification</A>) + */ +typedef struct { + FLAC__uint64 sample_number; + /**< The sample number of the target frame. */ + + FLAC__uint64 stream_offset; + /**< The offset, in bytes, of the target frame with respect to + * beginning of the first frame. */ + + uint32_t frame_samples; + /**< The number of samples in the target frame. */ +} FLAC__StreamMetadata_SeekPoint; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN; /**< == 64 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN; /**< == 64 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN; /**< == 16 (bits) */ + +/** The total stream length of a seek point in bytes. */ +#define FLAC__STREAM_METADATA_SEEKPOINT_LENGTH (18u) + +/** The value used in the \a sample_number field of + * FLAC__StreamMetadataSeekPoint used to indicate a placeholder + * point (== 0xffffffffffffffff). + */ +extern FLAC_API const FLAC__uint64 FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER; + + +/** FLAC SEEKTABLE structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_seektable">format specification</A>) + * + * \note From the format specification: + * - The seek points must be sorted by ascending sample number. + * - Each seek point's sample number must be the first sample of the + * target frame. + * - Each seek point's sample number must be unique within the table. + * - Existence of a SEEKTABLE block implies a correct setting of + * total_samples in the stream_info block. + * - Behavior is undefined when more than one SEEKTABLE block is + * present in a stream. + */ +typedef struct { + uint32_t num_points; + FLAC__StreamMetadata_SeekPoint *points; +} FLAC__StreamMetadata_SeekTable; + + +/** Vorbis comment entry structure used in VORBIS_COMMENT blocks. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_vorbis_comment">format specification</A>) + * + * For convenience, the APIs maintain a trailing NUL character at the end of + * \a entry which is not counted toward \a length, i.e. + * \code strlen(entry) == length \endcode + */ +typedef struct { + FLAC__uint32 length; + FLAC__byte *entry; +} FLAC__StreamMetadata_VorbisComment_Entry; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN; /**< == 32 (bits) */ + + +/** FLAC VORBIS_COMMENT structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block_vorbis_comment">format specification</A>) + */ +typedef struct { + FLAC__StreamMetadata_VorbisComment_Entry vendor_string; + FLAC__uint32 num_comments; + FLAC__StreamMetadata_VorbisComment_Entry *comments; +} FLAC__StreamMetadata_VorbisComment; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN; /**< == 32 (bits) */ + + +/** FLAC CUESHEET track index structure. (See the + * <A HREF="https://xiph.org/flac/format.html#cuesheet_track_index">format specification</A> for + * the full description of each field.) + */ +typedef struct { + FLAC__uint64 offset; + /**< Offset in samples, relative to the track offset, of the index + * point. + */ + + FLAC__byte number; + /**< The index point number. */ +} FLAC__StreamMetadata_CueSheet_Index; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN; /**< == 64 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN; /**< == 8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN; /**< == 3*8 (bits) */ + + +/** FLAC CUESHEET track structure. (See the + * <A HREF="https://xiph.org/flac/format.html#cuesheet_track">format specification</A> for + * the full description of each field.) + */ +typedef struct { + FLAC__uint64 offset; + /**< Track offset in samples, relative to the beginning of the FLAC audio stream. */ + + FLAC__byte number; + /**< The track number. */ + + char isrc[13]; + /**< Track ISRC. This is a 12-digit alphanumeric code plus a trailing \c NUL byte */ + + uint32_t type:1; + /**< The track type: 0 for audio, 1 for non-audio. */ + + uint32_t pre_emphasis:1; + /**< The pre-emphasis flag: 0 for no pre-emphasis, 1 for pre-emphasis. */ + + FLAC__byte num_indices; + /**< The number of track index points. */ + + FLAC__StreamMetadata_CueSheet_Index *indices; + /**< NULL if num_indices == 0, else pointer to array of index points. */ + +} FLAC__StreamMetadata_CueSheet_Track; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN; /**< == 64 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN; /**< == 8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN; /**< == 12*8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN; /**< == 1 (bit) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN; /**< == 1 (bit) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN; /**< == 6+13*8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN; /**< == 8 (bits) */ + + +/** FLAC CUESHEET structure. (See the + * <A HREF="https://xiph.org/flac/format.html#metadata_block_cuesheet">format specification</A> + * for the full description of each field.) + */ +typedef struct { + char media_catalog_number[129]; + /**< Media catalog number, in ASCII printable characters 0x20-0x7e. In + * general, the media catalog number may be 0 to 128 bytes long; any + * unused characters should be right-padded with NUL characters. + */ + + FLAC__uint64 lead_in; + /**< The number of lead-in samples. */ + + FLAC__bool is_cd; + /**< \c true if CUESHEET corresponds to a Compact Disc, else \c false. */ + + uint32_t num_tracks; + /**< The number of tracks. */ + + FLAC__StreamMetadata_CueSheet_Track *tracks; + /**< NULL if num_tracks == 0, else pointer to array of tracks. */ + +} FLAC__StreamMetadata_CueSheet; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN; /**< == 128*8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN; /**< == 64 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN; /**< == 1 (bit) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN; /**< == 7+258*8 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN; /**< == 8 (bits) */ + + +/** An enumeration of the PICTURE types (see FLAC__StreamMetadataPicture and id3 v2.4 APIC tag). */ +typedef enum { + FLAC__STREAM_METADATA_PICTURE_TYPE_OTHER = 0, /**< Other */ + FLAC__STREAM_METADATA_PICTURE_TYPE_FILE_ICON_STANDARD = 1, /**< 32x32 pixels 'file icon' (PNG only) */ + FLAC__STREAM_METADATA_PICTURE_TYPE_FILE_ICON = 2, /**< Other file icon */ + FLAC__STREAM_METADATA_PICTURE_TYPE_FRONT_COVER = 3, /**< Cover (front) */ + FLAC__STREAM_METADATA_PICTURE_TYPE_BACK_COVER = 4, /**< Cover (back) */ + FLAC__STREAM_METADATA_PICTURE_TYPE_LEAFLET_PAGE = 5, /**< Leaflet page */ + FLAC__STREAM_METADATA_PICTURE_TYPE_MEDIA = 6, /**< Media (e.g. label side of CD) */ + FLAC__STREAM_METADATA_PICTURE_TYPE_LEAD_ARTIST = 7, /**< Lead artist/lead performer/soloist */ + FLAC__STREAM_METADATA_PICTURE_TYPE_ARTIST = 8, /**< Artist/performer */ + FLAC__STREAM_METADATA_PICTURE_TYPE_CONDUCTOR = 9, /**< Conductor */ + FLAC__STREAM_METADATA_PICTURE_TYPE_BAND = 10, /**< Band/Orchestra */ + FLAC__STREAM_METADATA_PICTURE_TYPE_COMPOSER = 11, /**< Composer */ + FLAC__STREAM_METADATA_PICTURE_TYPE_LYRICIST = 12, /**< Lyricist/text writer */ + FLAC__STREAM_METADATA_PICTURE_TYPE_RECORDING_LOCATION = 13, /**< Recording Location */ + FLAC__STREAM_METADATA_PICTURE_TYPE_DURING_RECORDING = 14, /**< During recording */ + FLAC__STREAM_METADATA_PICTURE_TYPE_DURING_PERFORMANCE = 15, /**< During performance */ + FLAC__STREAM_METADATA_PICTURE_TYPE_VIDEO_SCREEN_CAPTURE = 16, /**< Movie/video screen capture */ + FLAC__STREAM_METADATA_PICTURE_TYPE_FISH = 17, /**< A bright coloured fish */ + FLAC__STREAM_METADATA_PICTURE_TYPE_ILLUSTRATION = 18, /**< Illustration */ + FLAC__STREAM_METADATA_PICTURE_TYPE_BAND_LOGOTYPE = 19, /**< Band/artist logotype */ + FLAC__STREAM_METADATA_PICTURE_TYPE_PUBLISHER_LOGOTYPE = 20, /**< Publisher/Studio logotype */ + FLAC__STREAM_METADATA_PICTURE_TYPE_UNDEFINED +} FLAC__StreamMetadata_Picture_Type; + +/** Maps a FLAC__StreamMetadata_Picture_Type to a C string. + * + * Using a FLAC__StreamMetadata_Picture_Type as the index to this array + * will give the string equivalent. The contents should not be + * modified. + */ +extern FLAC_API const char * const FLAC__StreamMetadata_Picture_TypeString[]; + +/** FLAC PICTURE structure. (See the + * <A HREF="https://xiph.org/flac/format.html#metadata_block_picture">format specification</A> + * for the full description of each field.) + */ +typedef struct { + FLAC__StreamMetadata_Picture_Type type; + /**< The kind of picture stored. */ + + char *mime_type; + /**< Picture data's MIME type, in ASCII printable characters + * 0x20-0x7e, NUL terminated. For best compatibility with players, + * use picture data of MIME type \c image/jpeg or \c image/png. A + * MIME type of '-->' is also allowed, in which case the picture + * data should be a complete URL. In file storage, the MIME type is + * stored as a 32-bit length followed by the ASCII string with no NUL + * terminator, but is converted to a plain C string in this structure + * for convenience. + */ + + FLAC__byte *description; + /**< Picture's description in UTF-8, NUL terminated. In file storage, + * the description is stored as a 32-bit length followed by the UTF-8 + * string with no NUL terminator, but is converted to a plain C string + * in this structure for convenience. + */ + + FLAC__uint32 width; + /**< Picture's width in pixels. */ + + FLAC__uint32 height; + /**< Picture's height in pixels. */ + + FLAC__uint32 depth; + /**< Picture's color depth in bits-per-pixel. */ + + FLAC__uint32 colors; + /**< For indexed palettes (like GIF), picture's number of colors (the + * number of palette entries), or \c 0 for non-indexed (i.e. 2^depth). + */ + + FLAC__uint32 data_length; + /**< Length of binary picture data in bytes. */ + + FLAC__byte *data; + /**< Binary picture data. */ + +} FLAC__StreamMetadata_Picture; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_TYPE_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_COLORS_LEN; /**< == 32 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN; /**< == 32 (bits) */ + + +/** Structure that is used when a metadata block of unknown type is loaded. + * The contents are opaque. The structure is used only internally to + * correctly handle unknown metadata. + */ +typedef struct { + FLAC__byte *data; +} FLAC__StreamMetadata_Unknown; + + +/** FLAC metadata block structure. (c.f. <A HREF="https://xiph.org/flac/format.html#metadata_block">format specification</A>) + */ +typedef struct FLAC__StreamMetadata { + FLAC__MetadataType type; + /**< The type of the metadata block; used determine which member of the + * \a data union to dereference. If type >= FLAC__METADATA_TYPE_UNDEFINED + * then \a data.unknown must be used. */ + + FLAC__bool is_last; + /**< \c true if this metadata block is the last, else \a false */ + + uint32_t length; + /**< Length, in bytes, of the block data as it appears in the stream. */ + + union { + FLAC__StreamMetadata_StreamInfo stream_info; + FLAC__StreamMetadata_Padding padding; + FLAC__StreamMetadata_Application application; + FLAC__StreamMetadata_SeekTable seek_table; + FLAC__StreamMetadata_VorbisComment vorbis_comment; + FLAC__StreamMetadata_CueSheet cue_sheet; + FLAC__StreamMetadata_Picture picture; + FLAC__StreamMetadata_Unknown unknown; + } data; + /**< Polymorphic block data; use the \a type value to determine which + * to use. */ +} FLAC__StreamMetadata; + +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_IS_LAST_LEN; /**< == 1 (bit) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_TYPE_LEN; /**< == 7 (bits) */ +extern FLAC_API const uint32_t FLAC__STREAM_METADATA_LENGTH_LEN; /**< == 24 (bits) */ + +/** The total stream length of a metadata block header in bytes. */ +#define FLAC__STREAM_METADATA_HEADER_LENGTH (4u) + +/*****************************************************************************/ + + +/***************************************************************************** + * + * Utility functions + * + *****************************************************************************/ + +/** Tests that a sample rate is valid for FLAC. + * + * \param sample_rate The sample rate to test for compliance. + * \retval FLAC__bool + * \c true if the given sample rate conforms to the specification, else + * \c false. + */ +FLAC_API FLAC__bool FLAC__format_sample_rate_is_valid(uint32_t sample_rate); + +/** Tests that a blocksize at the given sample rate is valid for the FLAC + * subset. + * + * \param blocksize The blocksize to test for compliance. + * \param sample_rate The sample rate is needed, since the valid subset + * blocksize depends on the sample rate. + * \retval FLAC__bool + * \c true if the given blocksize conforms to the specification for the + * subset at the given sample rate, else \c false. + */ +FLAC_API FLAC__bool FLAC__format_blocksize_is_subset(uint32_t blocksize, uint32_t sample_rate); + +/** Tests that a sample rate is valid for the FLAC subset. The subset rules + * for valid sample rates are slightly more complex since the rate has to + * be expressible completely in the frame header. + * + * \param sample_rate The sample rate to test for compliance. + * \retval FLAC__bool + * \c true if the given sample rate conforms to the specification for the + * subset, else \c false. + */ +FLAC_API FLAC__bool FLAC__format_sample_rate_is_subset(uint32_t sample_rate); + +/** Check a Vorbis comment entry name to see if it conforms to the Vorbis + * comment specification. + * + * Vorbis comment names must be composed only of characters from + * [0x20-0x3C,0x3E-0x7D]. + * + * \param name A NUL-terminated string to be checked. + * \assert + * \code name != NULL \endcode + * \retval FLAC__bool + * \c false if entry name is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_name_is_legal(const char *name); + +/** Check a Vorbis comment entry value to see if it conforms to the Vorbis + * comment specification. + * + * Vorbis comment values must be valid UTF-8 sequences. + * + * \param value A string to be checked. + * \param length A the length of \a value in bytes. May be + * \c (uint32_t)(-1) to indicate that \a value is a plain + * UTF-8 NUL-terminated string. + * \assert + * \code value != NULL \endcode + * \retval FLAC__bool + * \c false if entry name is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_value_is_legal(const FLAC__byte *value, uint32_t length); + +/** Check a Vorbis comment entry to see if it conforms to the Vorbis + * comment specification. + * + * Vorbis comment entries must be of the form 'name=value', and 'name' and + * 'value' must be legal according to + * FLAC__format_vorbiscomment_entry_name_is_legal() and + * FLAC__format_vorbiscomment_entry_value_is_legal() respectively. + * + * \param entry An entry to be checked. + * \param length The length of \a entry in bytes. + * \assert + * \code value != NULL \endcode + * \retval FLAC__bool + * \c false if entry name is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_vorbiscomment_entry_is_legal(const FLAC__byte *entry, uint32_t length); + +/** Check a seek table to see if it conforms to the FLAC specification. + * See the format specification for limits on the contents of the + * seek table. + * + * \param seek_table A pointer to a seek table to be checked. + * \assert + * \code seek_table != NULL \endcode + * \retval FLAC__bool + * \c false if seek table is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_seektable_is_legal(const FLAC__StreamMetadata_SeekTable *seek_table); + +/** Sort a seek table's seek points according to the format specification. + * This includes a "unique-ification" step to remove duplicates, i.e. + * seek points with identical \a sample_number values. Duplicate seek + * points are converted into placeholder points and sorted to the end of + * the table. + * + * \param seek_table A pointer to a seek table to be sorted. + * \assert + * \code seek_table != NULL \endcode + * \retval uint32_t + * The number of duplicate seek points converted into placeholders. + */ +FLAC_API uint32_t FLAC__format_seektable_sort(FLAC__StreamMetadata_SeekTable *seek_table); + +/** Check a cue sheet to see if it conforms to the FLAC specification. + * See the format specification for limits on the contents of the + * cue sheet. + * + * \param cue_sheet A pointer to an existing cue sheet to be checked. + * \param check_cd_da_subset If \c true, check CUESHEET against more + * stringent requirements for a CD-DA (audio) disc. + * \param violation Address of a pointer to a string. If there is a + * violation, a pointer to a string explanation of the + * violation will be returned here. \a violation may be + * \c NULL if you don't need the returned string. Do not + * free the returned string; it will always point to static + * data. + * \assert + * \code cue_sheet != NULL \endcode + * \retval FLAC__bool + * \c false if cue sheet is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_cuesheet_is_legal(const FLAC__StreamMetadata_CueSheet *cue_sheet, FLAC__bool check_cd_da_subset, const char **violation); + +/** Check picture data to see if it conforms to the FLAC specification. + * See the format specification for limits on the contents of the + * PICTURE block. + * + * \param picture A pointer to existing picture data to be checked. + * \param violation Address of a pointer to a string. If there is a + * violation, a pointer to a string explanation of the + * violation will be returned here. \a violation may be + * \c NULL if you don't need the returned string. Do not + * free the returned string; it will always point to static + * data. + * \assert + * \code picture != NULL \endcode + * \retval FLAC__bool + * \c false if picture data is illegal, else \c true. + */ +FLAC_API FLAC__bool FLAC__format_picture_is_legal(const FLAC__StreamMetadata_Picture *picture, const char **violation); + +/* \} */ + +#ifdef __cplusplus +} +#endif + +#endif |