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#ifndef _mpp_dec_h_
#define _mpp_dec_h_
#ifdef WIN32
#define MPC_LITTLE_ENDIAN
#endif
#include <assert.h>
#include "mpc_math.h"
class MPC_reader {
public:
virtual size_t read ( void *ptr, size_t size ) = 0;
virtual bool seek ( int offset, int origin ) = 0;
virtual long tell () = 0;
virtual long get_size () = 0;
virtual bool canseek() = 0;
};
class MPC_decoder {
public:
MPC_decoder(MPC_reader *r, double scale_factor = 1.0);
~MPC_decoder();
bool Initialize(const class StreamInfo *si);
void ScaleOutput(double factor);
unsigned int Decode(MPC_SAMPLE_FORMAT *buffer, unsigned int * vbr_update_acc = 0, unsigned int * vbr_update_bits = 0);
bool SeekSeconds(double seconds);
bool SeekSample(MPC_INT64 sample);
public:
enum
{
FrameLength = (36 * 32), // samples per frame
SynthDelay = 481,
DecodeBufferLength = 4 * FrameLength
};
private:
enum
{
EQ_TAP = 13, // length of FIR filter for EQ
DELAY = ((EQ_TAP + 1) / 2), // delay of FIR
FIR_BANDS = 4, // number of subbands to be FIR filtered
MEMSIZE = 16384, // overall buffer size
MEMSIZE2 = (MEMSIZE/2), // size of one buffer
MEMMASK = (MEMSIZE-1),
V_MEM = 2304
};
void SetStreamInfo ( const class StreamInfo *si );
void UpdateBuffer ( unsigned int RING );
void RESET_Synthesis ( void );
void RESET_Globals ( void );
unsigned int BitsRead ( void );
unsigned int decode_internal ( MPC_SAMPLE_FORMAT *buffer );
void RESET_Y ( void );
void Lese_Bitstrom_SV6 ( void );
void Lese_Bitstrom_SV7 ( void );
void Requantisierung ( const int Last_Band );
unsigned int samples_to_skip;
typedef struct {
int L [36];
int R [36];
} QuantTyp;
typedef struct {
unsigned int Code;
unsigned int Length;
int Value;
} HuffmanTyp;
static int HuffmanTyp_cmpfn ( const void* p1, const void* p2 );
MPC_reader *m_reader;
unsigned int dword; // actually decoded 32bit-word
unsigned int pos; // bit-position within dword
unsigned int Speicher [MEMSIZE]; // read-buffer
unsigned int Zaehler; // actual index within read-buffer
unsigned int FwdJumpInfo;
unsigned int ActDecodePos;
unsigned int FrameWasValid;
unsigned int DecodedFrames;
unsigned int OverallFrames;
int SampleRate; // Sample frequency
unsigned int StreamVersion; // version of bitstream
unsigned int MS_used; // MS-coding used ?
int Max_Band;
unsigned int MPCHeaderPos; // AB: needed to support ID3v2
//unsigned int OverallFrames;
//unsigned int DecodedFrames;
unsigned int LastValidSamples;
unsigned int TrueGaplessPresent;
unsigned int EQ_activated;
unsigned int WordsRead; // counts amount of decoded dwords
unsigned short* SeekTable;
/*static*/ unsigned int __r1;
/*static*/ unsigned int __r2;
int SCF_Index_L [32] [3];
int SCF_Index_R [32] [3]; // holds scalefactor-indices
QuantTyp Q [32]; // holds quantized samples
int Res_L [32];
int Res_R [32]; // holds the chosen quantizer for each subband
int DSCF_Flag_L [32];
int DSCF_Flag_R [32]; // differential SCF used?
int SCFI_L [32];
int SCFI_R [32]; // describes order of transmitted SCF
int DSCF_Reference_L [32];
int DSCF_Reference_R [32]; // holds last frames SCF
int MS_Flag[32]; // MS used?
HuffmanTyp HuffHdr [10];
HuffmanTyp HuffSCFI [ 4];
HuffmanTyp HuffDSCF [16];
HuffmanTyp* HuffQ [2] [8];
HuffmanTyp HuffQ1 [2] [3*3*3];
HuffmanTyp HuffQ2 [2] [5*5];
HuffmanTyp HuffQ3 [2] [ 7];
HuffmanTyp HuffQ4 [2] [ 9];
HuffmanTyp HuffQ5 [2] [15];
HuffmanTyp HuffQ6 [2] [31];
HuffmanTyp HuffQ7 [2] [63];
const HuffmanTyp* SampleHuff [18];
HuffmanTyp SCFI_Bundle [ 8];
HuffmanTyp DSCF_Entropie [13];
HuffmanTyp Region_A [16];
HuffmanTyp Region_B [ 8];
HuffmanTyp Region_C [ 4];
HuffmanTyp Entropie_1 [ 3];
HuffmanTyp Entropie_2 [ 5];
HuffmanTyp Entropie_3 [ 7];
HuffmanTyp Entropie_4 [ 9];
HuffmanTyp Entropie_5 [15];
HuffmanTyp Entropie_6 [31];
HuffmanTyp Entropie_7 [63];
MPC_SAMPLE_FORMAT V_L [V_MEM + 960];
MPC_SAMPLE_FORMAT V_R [V_MEM + 960];
MPC_SAMPLE_FORMAT Y_L [36] [32];
MPC_SAMPLE_FORMAT Y_R [36] [32];
MPC_SAMPLE_FORMAT SCF [256]; // holds adapted scalefactors (for clipping prevention)
#ifdef MPC_FIXED_POINT
unsigned char SCF_shift[256];
#endif
unsigned int Q_bit [32]; // holds amount of bits to save chosen quantizer (SV6)
unsigned int Q_res [32] [16]; // holds conversion: index -> quantizer (SV6)
private: // functions
void Reset_BitstreamDecode ( void );
unsigned int Bitstream_read ( const unsigned int );
int Huffman_Decode ( const HuffmanTyp* ); // works with maximum lengths up to 14
int Huffman_Decode_fast ( const HuffmanTyp* ); // works with maximum lengths up to 10
int Huffman_Decode_faster ( const HuffmanTyp* ); // works with maximum lengths up to 5
void SCFI_Bundle_read ( const HuffmanTyp*, int*, int* );
void Reset_V ( void );
void Synthese_Filter_float ( MPC_SAMPLE_FORMAT * dst );
unsigned int random_int ( void );
void EQSet ( int on, char data[10], int preamp );
void Helper1 ( unsigned long bitpos );
void Helper2 ( unsigned long bitpos );
void Helper3 ( unsigned long bitpos, unsigned long* buffoffs );
void Huffman_SV6_Encoder ( void );
void Huffman_SV6_Decoder ( void );
void Huffman_SV7_Encoder ( void );
void Huffman_SV7_Decoder ( void );
void initialisiere_Quantisierungstabellen ( double );
void Quantisierungsmodes ( void ); // conversion: index -> quantizer (bitstream reading)
void Resort_HuffTables ( const unsigned int elements, HuffmanTyp* Table, const int offset );
private:
inline int f_read ( void *ptr, size_t size) { return m_reader->read (ptr, size); };
int f_read_dword( unsigned int * ptr, unsigned int count);
inline bool f_seek ( int offset, int origin) { return m_reader->seek (offset, origin); };
};
#include "streaminfo.h"
#endif
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