| /* libFLAC - Free Lossless Audio Coder library |
| * Copyright (C) 2000,2001 Josh Coalson |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public |
| * License along with this library; if not, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 02111-1307, USA. |
| */ |
| |
| #ifndef FLAC__FORMAT_H |
| #define FLAC__FORMAT_H |
| |
| #include "ordinals.h" |
| |
| /* changing the following values to be higher will break the framing and hence the stream format, so DON'T! */ |
| #define FLAC__MIN_BLOCK_SIZE (16u) |
| #define FLAC__MAX_BLOCK_SIZE (65535u) |
| #define FLAC__MAX_CHANNELS (8u) |
| /*NOTE: only up to 24 because of the current predictor coefficient quantization and the fact we use int32s for all work */ |
| #define FLAC__MAX_BITS_PER_SAMPLE (24u) |
| /* the following is ((2 ** 20) - 1) div 10 */ |
| #define FLAC__MAX_SAMPLE_RATE (1048570u) |
| #define FLAC__MAX_LPC_ORDER (32u) |
| #define FLAC__MIN_QLP_COEFF_PRECISION (5u) |
| /* changing this also means changing all of fixed.c and more, so DON'T! */ |
| #define FLAC__MAX_FIXED_ORDER (4u) |
| #define FLAC__MAX_RICE_PARTITION_ORDER (15u) |
| |
| /* VERSION comes from configure */ |
| #define FLAC__VERSION_STRING VERSION |
| extern const unsigned FLAC__MAJOR_VERSION; |
| extern const unsigned FLAC__MINOR_VERSION; |
| |
| extern const byte FLAC__STREAM_SYNC_STRING[4]; /* = "fLaC" */; |
| extern const unsigned FLAC__STREAM_SYNC; /* = 0x664C6143 */; |
| extern const unsigned FLAC__STREAM_SYNC_LEN; /* = 32 bits */; |
| |
| |
| /***************************************************************************** |
| * |
| * NOTE: Within the bitstream, all fixed-width numbers are big-endian coded. |
| * All numbers are unsigned unless otherwise noted. |
| * |
| *****************************************************************************/ |
| |
| |
| /***************************************************************************** |
| * |
| * Subframe structures |
| * |
| *****************************************************************************/ |
| |
| /*****************************************************************************/ |
| |
| typedef enum { |
| FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE = 0 |
| } FLAC__EntropyCodingMethodType; |
| extern const char *FLAC__EntropyCodingMethodTypeString[]; |
| |
| /***************************************************************************** |
| * |
| * 4: partition order => (2 ** order) subdivisions |
| */ |
| typedef struct { |
| unsigned order; |
| unsigned parameters[1 << FLAC__MAX_RICE_PARTITION_ORDER]; |
| } FLAC__EntropyCodingMethod_PartitionedRice; |
| |
| extern const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN; /* = 4 bits */ |
| extern const unsigned FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; /* = 4 bits */ |
| |
| /***************************************************************************** |
| * |
| * 2: entropy coding method: |
| * 00: partitioned rice coding |
| * 01-11: reserved |
| * ?: entropy coding method data |
| */ |
| typedef struct { |
| FLAC__EntropyCodingMethodType type; |
| union { |
| FLAC__EntropyCodingMethod_PartitionedRice partitioned_rice; |
| } data; |
| } FLAC__EntropyCodingMethod; |
| |
| extern const unsigned FLAC__ENTROPY_CODING_METHOD_TYPE_LEN; /* = 2 bits */ |
| |
| /*****************************************************************************/ |
| |
| typedef enum { |
| FLAC__SUBFRAME_TYPE_CONSTANT = 0, |
| FLAC__SUBFRAME_TYPE_VERBATIM = 1, |
| FLAC__SUBFRAME_TYPE_FIXED = 2, |
| FLAC__SUBFRAME_TYPE_LPC = 3 |
| } FLAC__SubframeType; |
| extern const char *FLAC__SubframeTypeString[]; |
| |
| /***************************************************************************** |
| * |
| * n: constant value for signal; n = frame's bits-per-sample |
| */ |
| typedef struct { |
| int32 value; |
| } FLAC__Subframe_Constant; |
| |
| /***************************************************************************** |
| * |
| * n*i: unencoded signal; n = frame's bits-per-sample, i = frame's blocksize |
| */ |
| typedef struct { |
| int32 *data; |
| } FLAC__Subframe_Verbatim; |
| |
| /***************************************************************************** |
| * |
| * n: unencoded warm-up samples (n = fixed-predictor order * bits per sample) |
| * ?: entropy coding method info |
| * ?: encoded residual ((blocksize minus fixed-predictor order) samples) |
| * The order is stored in the main subframe header |
| */ |
| typedef struct { |
| FLAC__EntropyCodingMethod entropy_coding_method; |
| unsigned order; |
| int32 warmup[FLAC__MAX_FIXED_ORDER]; |
| int32 *residual; |
| } FLAC__Subframe_Fixed; |
| |
| /***************************************************************************** |
| * |
| * n: unencoded warm-up samples (n = lpc order * bits per sample) |
| * 4: (qlp coeff precision in bits)-1 (1111 = invalid, use to check for erroneous sync) |
| * 5: qlp shift needed in bits (signed) |
| * n: unencoded predictor coefficients (n = lpc order * qlp coeff precision) |
| * ?: entropy coding method info |
| * ?: encoded residual ((blocksize minus lpc order) samples) |
| * The order is stored in the main subframe header |
| */ |
| typedef struct { |
| FLAC__EntropyCodingMethod entropy_coding_method; |
| unsigned order; |
| unsigned qlp_coeff_precision; |
| int quantization_level; |
| int32 qlp_coeff[FLAC__MAX_LPC_ORDER]; |
| int32 warmup[FLAC__MAX_LPC_ORDER]; |
| int32 *residual; |
| } FLAC__Subframe_LPC; |
| |
| extern const unsigned FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN; /* = 4 bits */ |
| extern const unsigned FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN; /* = 5 bits */ |
| |
| /***************************************************************************** |
| * |
| * 8: subframe type |
| * xxxxxxx1: invalid, to prevent sync-fooling string of 1s (use to check for erroneous sync) |
| * 00000000: constant value |
| * 00000010: verbatim |
| * 000001x0: reserved |
| * 00001xx0: reserved |
| * 0001xxx0: fixed predictor, xxx=order <= 4, else reserved |
| * 001xxxx0: reserved |
| * 01xxxxx0: lpc, xxxxx=order-1 |
| * 1xxxxxxx: invalid, to prevent sync-fooling string of 1s (use to check for erroneous sync) |
| * ?: subframe-specific data (c.f. FLAC__Subframe_*) |
| */ |
| typedef struct { |
| FLAC__SubframeType type; |
| union { |
| FLAC__Subframe_Constant constant; |
| FLAC__Subframe_Fixed fixed; |
| FLAC__Subframe_LPC lpc; |
| FLAC__Subframe_Verbatim verbatim; |
| } data; |
| } FLAC__Subframe; |
| |
| extern const unsigned FLAC__SUBFRAME_TYPE_CONSTANT_BITS; /* = 0x00 */ |
| extern const unsigned FLAC__SUBFRAME_TYPE_VERBATIM_BITS; /* = 0x02 */ |
| extern const unsigned FLAC__SUBFRAME_TYPE_FIXED_BITS; /* = 0x10 */ |
| extern const unsigned FLAC__SUBFRAME_TYPE_LPC_BITS; /* = 0x40 */ |
| extern const unsigned FLAC__SUBFRAME_TYPE_LEN; /* = 8 bits */ |
| |
| /*****************************************************************************/ |
| |
| |
| /***************************************************************************** |
| * |
| * Frame structures |
| * |
| *****************************************************************************/ |
| |
| typedef enum { |
| FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT = 0, |
| FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE = 1, |
| FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE = 2, |
| FLAC__CHANNEL_ASSIGNMENT_MID_SIDE = 3 |
| } FLAC__ChannelAssignment; |
| extern const char *FLAC__ChannelAssignmentString[]; |
| |
| /***************************************************************************** |
| * |
| * 9: sync code '111111110' |
| * 3: blocksize in samples |
| * 000: get from stream header => implies constant blocksize throughout stream |
| * 001: 192 samples (AES/EBU) => implies constant blocksize throughout stream |
| * 010-101: 576 * (2^(2-n)) samples, i.e. 576/1152/2304/4608 => implies constant blocksize throughout stream |
| * 110: get 8 bit (blocksize-1) from end of header => variable blocksize throughout stream unless it's the last frame |
| * 111: get 16 bit (blocksize-1) from end of header => variable blocksize throughout stream unless it's the last frame |
| * 4: sample rate: |
| * 0000: get from stream header |
| * 0001-0011: reserved |
| * 0100: 8kHz |
| * 0101: 16kHz |
| * 0110: 22.05kHz |
| * 0111: 24kHz |
| * 1000: 32kHz |
| * 1001: 44.1kHz |
| * 1010: 48kHz |
| * 1011: 96kHz |
| * 1100: get 8 bit sample rate (in kHz) from end of header |
| * 1101: get 16 bit sample rate (in Hz) from end of header |
| * 1110: get 16 bit sample rate (in tens of Hz) from end of header |
| * 1111: invalid, to prevent sync-fooling string of 1s (use to check for erroneous sync) |
| * 4: channel assignment |
| * 0000-0111: (number of independent channels)-1. when == 0001, channel 0 is the left channel and channel 1 is the right |
| * 1000: left/side stereo : channel 0 is the left channel, channel 1 is the side(difference) channel |
| * 1001: right/side stereo: channel 0 is the side(difference) channel, channel 1 is the right channel |
| * 1010: mid/side stereo : channel 0 is the mid(average) channel, channel 1 is the side(difference) channel |
| * 1011-1111: reserved |
| * 3: sample size in bits |
| * 000: get from stream header |
| * 001: 8 bits per sample |
| * 010: 12 bits per sample |
| * 011: reserved |
| * 100: 16 bits per sample |
| * 101: 20 bits per sample |
| * 110: 24 bits per sample |
| * 111: reserved |
| * 1: zero pad, to prevent sync-fooling string of 1s (use to check for erroneous sync) |
| * ?: if(variable blocksize) |
| * 8-56: 'UTF-8' coded sample number (decoded number is 0-36 bits) (use to check for erroneous sync) |
| * else |
| * 8-48: 'UTF-8' coded frame number (decoded number is 0-31 bits) (use to check for erroneous sync) |
| * ?: if(blocksize bits == 11x) |
| * 8/16 bit (blocksize-1) |
| * ?: if(sample rate bits == 11xx) |
| * 8/16 bit sample rate |
| * 8: CRC-8 (polynomial = x^8 + x^2 + x + 1) of everything before the crc, including the sync code |
| */ |
| typedef struct { |
| unsigned blocksize; /* in samples */ |
| unsigned sample_rate; /* in Hz */ |
| unsigned channels; |
| FLAC__ChannelAssignment channel_assignment; |
| unsigned bits_per_sample; |
| union { |
| uint32 frame_number; |
| uint64 sample_number; |
| } number; |
| } FLAC__FrameHeader; |
| |
| extern const unsigned FLAC__FRAME_HEADER_SYNC; /* = 0x1fe */ |
| extern const unsigned FLAC__FRAME_HEADER_SYNC_LEN; /* = 9 bits */ |
| extern const unsigned FLAC__FRAME_HEADER_BLOCK_SIZE_LEN; /* = 3 bits */ |
| extern const unsigned FLAC__FRAME_HEADER_SAMPLE_RATE_LEN; /* = 4 bits */ |
| extern const unsigned FLAC__FRAME_HEADER_CHANNEL_ASSIGNMENT_LEN; /* = 4 bits */ |
| extern const unsigned FLAC__FRAME_HEADER_BITS_PER_SAMPLE_LEN; /* = 3 bits */ |
| extern const unsigned FLAC__FRAME_HEADER_ZERO_PAD_LEN; /* = 1 bit */ |
| extern const unsigned FLAC__FRAME_HEADER_CRC8_LEN; /* = 8 bits */ |
| |
| typedef struct { |
| FLAC__FrameHeader header; |
| FLAC__Subframe subframes[FLAC__MAX_CHANNELS]; |
| } FLAC__Frame; |
| |
| /*****************************************************************************/ |
| |
| |
| /***************************************************************************** |
| * |
| * Meta-data structures |
| * |
| *****************************************************************************/ |
| |
| typedef enum { |
| FLAC__METADATA_TYPE_ENCODING = 0 |
| } FLAC__MetaDataType; |
| extern const char *FLAC__MetaDataTypeString[]; |
| |
| /***************************************************************************** |
| * |
| * 16: minimum blocksize (in samples) of all blocks in the stream |
| * 16: maximum blocksize (in samples) of all blocks in the stream |
| * 24: minimum framesize (in bytes) of all frames in the stream; 0 => unknown |
| * 24: maximum framesize (in bytes) of all frames in the stream; 0 => unknown |
| * 20: sample rate in Hz, 0 is invalid |
| * 3: (number of channels)-1 |
| * 5: (bits per sample)-1 |
| * 36: total samples, 0 => unknown |
| *128: MD5 digest of the original unencoded audio data |
| *---- ----------------- |
| * 34 bytes total |
| */ |
| typedef struct { |
| unsigned min_blocksize, max_blocksize; |
| unsigned min_framesize, max_framesize; |
| unsigned sample_rate; |
| unsigned channels; |
| unsigned bits_per_sample; |
| uint64 total_samples; |
| byte md5sum[16]; |
| } FLAC__StreamMetaData_Encoding; |
| |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_MIN_BLOCK_SIZE_LEN; /* = 16 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_MAX_BLOCK_SIZE_LEN; /* = 16 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_MIN_FRAME_SIZE_LEN; /* = 24 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_MAX_FRAME_SIZE_LEN; /* = 24 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_SAMPLE_RATE_LEN; /* = 20 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_CHANNELS_LEN; /* = 3 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_BITS_PER_SAMPLE_LEN; /* = 5 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_TOTAL_SAMPLES_LEN; /* = 36 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_MD5SUM_LEN; /* = 128 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_ENCODING_LENGTH; /* = 34 bytes */ |
| |
| /***************************************************************************** |
| * |
| * 1: =1 if this is the last meta-data block, else =0 |
| * 7: meta-data type (c.f. FLAC__MetaDataType) |
| * 24: length (in bytes) of the block-specific data to follow |
| *---- ----------------- |
| * 4 bytes total |
| */ |
| typedef struct { |
| FLAC__MetaDataType type; |
| bool is_last; |
| unsigned length; /* in bytes */ |
| union { |
| FLAC__StreamMetaData_Encoding encoding; |
| } data; |
| } FLAC__StreamMetaData; |
| |
| extern const unsigned FLAC__STREAM_METADATA_IS_LAST_LEN; /* = 1 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_TYPE_LEN; /* = 7 bits */ |
| extern const unsigned FLAC__STREAM_METADATA_LENGTH_LEN; /* = 24 bits */ |
| |
| /*****************************************************************************/ |
| |
| |
| /***************************************************************************** |
| * |
| * Stream structures |
| * |
| *****************************************************************************/ |
| |
| typedef struct { |
| FLAC__StreamMetaData_Encoding metadata; |
| FLAC__Frame *frames; |
| } FLAC__Stream; |
| |
| /*****************************************************************************/ |
| |
| #endif |