rockbox/apps/codecs/libwavpack/wavpack.h

////////////////////////////////////////////////////////////////////////////
//                           **** WAVPACK ****                            //
//                  Hybrid Lossless Wavefile Compressor                   //
//              Copyright (c) 1998 - 2004 Conifer Software.               //
//                          All Rights Reserved.                          //
//      Distributed under the BSD Software License (see license.txt)      //
////////////////////////////////////////////////////////////////////////////

// wavpack.h

#include <inttypes.h>

// This header file contains all the definitions required by WavPack.

// not sure about them.. testing will bring more light into it..
typedef unsigned char	uchar;
typedef unsigned short	ushort;
typedef unsigned long	ulong;
typedef unsigned int	uint;

// This structure is used to access the individual fields of 32-bit ieee
// floating point numbers. This will not be compatible with compilers that
// allocate bit fields from the most significant bits, although I'm not sure
// how common that is.

typedef struct {
    unsigned mantissa : 23;
    unsigned exponent : 8;
    unsigned sign : 1;
} f32;

#include <stdio.h>

#define FALSE 0
#define TRUE 1

////////////////////////////// WavPack Header /////////////////////////////////

// Note that this is the ONLY structure that is written to (or read from)
// WavPack 4.0 files, and is the preamble to every block in both the .wv
// and .wvc files.

typedef struct {
    char ckID [4];
    ulong ckSize;
    short version;
    uchar track_no, index_no;
    ulong total_samples, block_index, block_samples, flags, crc;
} WavpackHeader;

#define WavpackHeaderFormat "4LS2LLLLL"

// or-values for "flags"

#define BYTES_STORED	3	// 1-4 bytes/sample
#define MONO_FLAG	4	// not stereo
#define HYBRID_FLAG	8	// hybrid mode
#define JOINT_STEREO	0x10	// joint stereo
#define CROSS_DECORR	0x20	// no-delay cross decorrelation
#define HYBRID_SHAPE	0x40	// noise shape (hybrid mode only)
#define FLOAT_DATA	0x80	// ieee 32-bit floating point data

#define INT32_DATA	0x100	// special extended int handling
#define HYBRID_BITRATE	0x200	// bitrate noise (hybrid mode only)
#define HYBRID_BALANCE	0x400	// balance noise (hybrid stereo mode only)

#define INITIAL_BLOCK	0x800	// initial block of multichannel segment
#define FINAL_BLOCK	0x1000	// final block of multichannel segment

#define SHIFT_LSB	13
#define SHIFT_MASK	(0x1fL << SHIFT_LSB)

#define MAG_LSB		18
#define MAG_MASK	(0x1fL << MAG_LSB)

#define SRATE_LSB	23
#define SRATE_MASK	(0xfL << SRATE_LSB)

#define IGNORED_FLAGS	0x18000000	// reserved, but ignore if encountered
#define NEW_SHAPING	0x20000000	// use IIR filter for negative shaping
#define UNKNOWN_FLAGS	0xC0000000	// also reserved, but refuse decode if
					//  encountered

//////////////////////////// WavPack Metadata /////////////////////////////////

// This is an internal representation of metadata.

typedef struct {
    long byte_length;
    void *data;
    uchar id;
} WavpackMetadata;

#define ID_OPTIONAL_DATA	0x20
#define ID_ODD_SIZE		0x40
#define ID_LARGE		0x80

#define ID_DUMMY		0x0
#define ID_ENCODER_INFO		0x1
#define ID_DECORR_TERMS		0x2
#define ID_DECORR_WEIGHTS	0x3
#define ID_DECORR_SAMPLES	0x4
#define ID_ENTROPY_VARS		0x5
#define ID_HYBRID_PROFILE	0x6
#define ID_SHAPING_WEIGHTS	0x7
#define ID_FLOAT_INFO		0x8
#define ID_INT32_INFO		0x9
#define ID_WV_BITSTREAM		0xa
#define ID_WVC_BITSTREAM	0xb
#define ID_WVX_BITSTREAM	0xc
#define ID_CHANNEL_INFO		0xd

#define ID_RIFF_HEADER		(ID_OPTIONAL_DATA | 0x1)
#define ID_RIFF_TRAILER		(ID_OPTIONAL_DATA | 0x2)
#define ID_REPLAY_GAIN		(ID_OPTIONAL_DATA | 0x3)
#define ID_CUESHEET		(ID_OPTIONAL_DATA | 0x4)
#define ID_CONFIG_BLOCK		(ID_OPTIONAL_DATA | 0x5)
#define ID_MD5_CHECKSUM		(ID_OPTIONAL_DATA | 0x6)

///////////////////////// WavPack Configuration ///////////////////////////////

// This internal structure is used during encode to provide configuration to
// the encoding engine and during decoding to provide fle information back to
// the higher level functions. Not all fields are used in both modes.

typedef struct {
    int bits_per_sample, bytes_per_sample;
    int qmode, flags, xmode, num_channels, float_norm_exp;
    long block_samples, extra_flags, sample_rate, channel_mask;
} WavpackConfig;

#define CONFIG_BYTES_STORED	3	// 1-4 bytes/sample
#define CONFIG_MONO_FLAG	4	// not stereo
#define CONFIG_HYBRID_FLAG	8	// hybrid mode
#define CONFIG_JOINT_STEREO	0x10	// joint stereo
#define CONFIG_CROSS_DECORR	0x20	// no-delay cross decorrelation
#define CONFIG_HYBRID_SHAPE	0x40	// noise shape (hybrid mode only)
#define CONFIG_FLOAT_DATA	0x80	// ieee 32-bit floating point data

#define CONFIG_ADOBE_MODE	0x100	// "adobe" mode for 32-bit floats
#define CONFIG_FAST_FLAG	0x200	// fast mode
#define CONFIG_VERY_FAST_FLAG	0x400	// double fast
#define CONFIG_HIGH_FLAG	0x800	// high quality mode
#define CONFIG_VERY_HIGH_FLAG	0x1000	// double high (not used yet)
#define CONFIG_BITRATE_KBPS	0x2000	// bitrate is kbps, not bits / sample
#define CONFIG_AUTO_SHAPING	0x4000	// automatic noise shaping
#define CONFIG_SHAPE_OVERRIDE	0x8000	// shaping mode specified
#define CONFIG_JOINT_OVERRIDE	0x10000	// joint-stereo mode specified
#define CONFIG_COPY_TIME	0x20000	// copy file-time from source
#define CONFIG_CREATE_EXE	0x40000	// create executable (not yet)
#define CONFIG_CREATE_WVC	0x80000	// create correction file
#define CONFIG_OPTIMIZE_WVC	0x100000 // maximize bybrid compression
#define CONFIG_QUALITY_MODE	0x200000 // psychoacoustic quality mode
#define CONFIG_RAW_FLAG		0x400000 // raw mode (not implemented yet)
#define CONFIG_CALC_NOISE	0x800000 // calc noise in hybrid mode
#define CONFIG_LOSSY_MODE	0x1000000 // obsolete (for information)
#define CONFIG_EXTRA_MODE	0x2000000 // extra processing mode
#define CONFIG_SKIP_WVX		0x4000000 // no wvx stream w/ floats & big ints
#define CONFIG_MD5_CHECKSUM	0x8000000 // compute & store MD5 signature
#define CONFIG_QUIET_MODE	0x10000000 // don't report progress %

//////////////////////////////// WavPack Stream ///////////////////////////////

// This internal structure contains everything required to handle a WavPack
// "stream", which is defined as a stereo or mono stream of audio samples. For
// multichannel audio several of these would be required. Each stream contains
// pointers to hold a complete allocated block of WavPack data, although it's
// possible to decode WavPack blocks without buffering an entire block.

typedef long (*read_stream)(void *, long);

typedef struct bs {
    uchar *buf, *end, *ptr;
    void (*wrap)(struct bs *bs);
    ulong file_bytes, sr;
    int error, bc;
    read_stream file;
} Bitstream;

#define MAX_NTERMS 16
#define MAX_TERM 8

struct decorr_pass {
    short term, delta, weight_A, weight_B;
    long samples_A [MAX_TERM], samples_B [MAX_TERM];
};

typedef struct {
    WavpackHeader wphdr;

    int num_terms, mute_error;
    ulong sample_index, crc;
    Bitstream wvbits;

    uchar int32_sent_bits, int32_zeros, int32_ones, int32_dups;
    uchar float_flags, float_shift, float_max_exp, float_norm_exp;
 
    struct decorr_pass decorr_passes [MAX_NTERMS];

    struct {
	ulong bitrate_delta [2], bitrate_acc [2];
	ulong median [3] [2], slow_level [2], error_limit [2];
	ulong pend_data, holding_one, zeros_acc;
	int holding_zero, pend_count;
    } w;
} WavpackStream;

// flags for float_flags:

#define FLOAT_SHIFT_ONES 1	// bits left-shifted into float = '1'
#define FLOAT_SHIFT_SAME 2	// bits left-shifted into float are the same
#define FLOAT_SHIFT_SENT 4	// bits shifted into float are sent literally
#define FLOAT_ZEROS_SENT 8	// "zeros" are not all real zeros
#define FLOAT_NEG_ZEROS  0x10	// contains negative zeros
#define FLOAT_EXCEPTIONS 0x20	// contains exceptions (inf, nan, etc.)

/////////////////////////////// WavPack Context ///////////////////////////////

// This internal structure holds everything required to encode or decode WavPack
// files. It is recommended that direct access to this structure be minimized
// and the provided utilities used instead.

typedef struct {
    WavpackConfig config;
    WavpackStream stream;

    uchar read_buffer [1024];
    char error_message [80];

    read_stream infile;
    ulong total_samples, crc_errors, first_flags;
    int open_flags, norm_offset, reduced_channels, lossy_blocks;

} WavpackContext;

//////////////////////// function prototypes and macros //////////////////////

#define CLEAR(destin) memset (&destin, 0, sizeof (destin));

// bits.c

void bs_open_read (Bitstream *bs, uchar *buffer_start, uchar *buffer_end, read_stream file, ulong file_bytes);

#define bs_is_open(bs) ((bs)->ptr != NULL)

#define getbit(bs) ( \
    (((bs)->bc) ? \
	((bs)->bc--, (bs)->sr & 1) : \
	    (((++((bs)->ptr) != (bs)->end) ? (void) 0 : (bs)->wrap (bs)), (bs)->bc = 7, ((bs)->sr = *((bs)->ptr)) & 1) \
    ) ? \
	((bs)->sr >>= 1, 1) : \
	((bs)->sr >>= 1, 0) \
)

#define getbits(value, nbits, bs) { \
    while ((nbits) > (bs)->bc) { \
	if (++((bs)->ptr) == (bs)->end) (bs)->wrap (bs); \
	(bs)->sr |= (long)*((bs)->ptr) << (bs)->bc; \
	(bs)->bc += 8; \
    } \
    *(value) = (bs)->sr; \
    (bs)->sr >>= (nbits); \
    (bs)->bc -= (nbits); \
}

void little_endian_to_native (void *data, char *format);
void native_to_little_endian (void *data, char *format);

// unpack.c

int unpack_init (WavpackContext *wpc);
int init_wv_bitstream (WavpackContext *wpc, WavpackMetadata *wpmd);
int read_decorr_terms (WavpackStream *wps, WavpackMetadata *wpmd);
int read_decorr_weights (WavpackStream *wps, WavpackMetadata *wpmd);
int read_decorr_samples (WavpackStream *wps, WavpackMetadata *wpmd);
int read_float_info (WavpackStream *wps, WavpackMetadata *wpmd);
int read_int32_info (WavpackStream *wps, WavpackMetadata *wpmd);
int read_channel_info (WavpackContext *wpc, WavpackMetadata *wpmd);
int read_config_info (WavpackContext *wpc, WavpackMetadata *wpmd);
long unpack_samples (WavpackContext *wpc, long *buffer, ulong sample_count);
int check_crc_error (WavpackContext *wpc);

// metadata.c stuff

int read_metadata_buff (WavpackContext *wpc, WavpackMetadata *wpmd);
int process_metadata (WavpackContext *wpc, WavpackMetadata *wpmd);

// words.c stuff

int read_entropy_vars (WavpackStream *wps, WavpackMetadata *wpmd);
int read_hybrid_profile (WavpackStream *wps, WavpackMetadata *wpmd);
long get_word (WavpackStream *wps, int chan);
long exp2s (int log);
int restore_weight (char weight);

#define WORD_EOF (1L << 31)

// float.c

int read_float_info (WavpackStream *wps, WavpackMetadata *wpmd);
void float_values (WavpackStream *wps, long *values, long num_values);
void float_normalize (long *values, long num_values, int delta_exp);

// wputils.c

WavpackContext *WavpackOpenFileInput (read_stream infile, char *error);

int WavpackGetMode (WavpackContext *wpc);

#define MODE_WVC	0x1
#define MODE_LOSSLESS	0x2
#define MODE_HYBRID	0x4
#define MODE_FLOAT	0x8
#define MODE_VALID_TAG	0x10
#define MODE_HIGH	0x20
#define MODE_FAST	0x40

ulong WavpackUnpackSamples (WavpackContext *wpc, long *buffer, ulong samples);
ulong WavpackGetNumSamples (WavpackContext *wpc);
ulong WavpackGetSampleIndex (WavpackContext *wpc);
int WavpackGetNumErrors (WavpackContext *wpc);
int WavpackLossyBlocks (WavpackContext *wpc);
ulong WavpackGetSampleRate (WavpackContext *wpc);
int WavpackGetBitsPerSample (WavpackContext *wpc);
int WavpackGetBytesPerSample (WavpackContext *wpc);
int WavpackGetNumChannels (WavpackContext *wpc);
int WavpackGetReducedChannels (WavpackContext *wpc);