aacsbr.h

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/* ***** BEGIN LICENSE BLOCK *****  
 * Source last modified: $Id: aacsbr.h,v 1.2 2005/05/20 18:05:41 jrecker Exp $ 
 *   
 * Portions Copyright (c) 1995-2005 RealNetworks, Inc. All Rights Reserved.  
 *       
 * The contents of this file, and the files included with this file, 
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 * the file under the current version of the RealNetworks Community 
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 * http://www.helixcommunity.org/content/rcsl, in which case the RCSL 
 * will apply. You may also obtain the license terms directly from 
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 * to this file, the RCSL.  Please see the applicable RPSL or RCSL for 
 * the rights, obligations and limitations governing use of the 
 * contents of the file. 
 *   
 * This file is part of the Helix DNA Technology. RealNetworks is the 
 * developer of the Original Code and owns the copyrights in the 
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 * ***** END LICENSE BLOCK ***** */  

/**************************************************************************************
 * Fixed-point HE-AAC decoder
 * Jon Recker (jrecker@real.com)
 * February 2005
 *
 * aacsbr.h - definitions of platform-specific SBR data structures, functions, and tables
 **************************************************************************************/

#ifndef _SBR_H
#define _SBR_H

#include "aaccommon.h"
#include "aacbitstream.h"

#ifndef ASSERT
#if defined(_WIN32) && defined(_M_IX86) && (defined (_DEBUG) || defined (REL_ENABLE_ASSERTS))
#define ASSERT(x) if (!(x)) __asm int 3;
#else
#define ASSERT(x) /* do nothing */
#endif
#endif

#ifndef MAX
#define MAX(a,b)    ((a) > (b) ? (a) : (b))
#endif

#ifndef MIN
#define MIN(a,b)    ((a) < (b) ? (a) : (b))
#endif

#define NUM_TIME_SLOTS          16
#define SAMPLES_PER_SLOT        2   /* RATE in spec */
#define NUM_SAMPLE_RATES_SBR    9   /* downsampled (single-rate) mode unsupported, so only use Fs_sbr >= 16 kHz */

#define MAX_NUM_ENV                 5
#define MAX_NUM_NOISE_FLOORS        2
#define MAX_NUM_NOISE_FLOOR_BANDS   5   /* max Nq, see 4.6.18.3.6 */
#define MAX_NUM_PATCHES             5
#define MAX_NUM_SMOOTH_COEFS        5

#define HF_GEN          8
#define HF_ADJ          2

#define MAX_QMF_BANDS   48      /* max QMF subbands covered by SBR (4.6.18.3.6) */

#define FBITS_IN_QMFA   14
#define FBITS_LOST_QMFA (1 + 2 + 3 + 2 + 1) /* 1 from cTab, 2 in premul, 3 in FFT, 2 in postmul, 1 for implicit scaling by 2.0 */
#define FBITS_OUT_QMFA  (FBITS_IN_QMFA - FBITS_LOST_QMFA)

#define MIN_GBITS_IN_QMFS       2
#define FBITS_IN_QMFS           FBITS_OUT_QMFA
#define FBITS_LOST_DCT4_64      (2 + 3 + 2)     /* 2 in premul, 3 in FFT, 2 in postmul */

#define FBITS_OUT_DQ_ENV    29  /* dequantized env scalefactors are Q(29 - envDataDequantScale) */
#define FBITS_OUT_DQ_NOISE  24  /* range of Q_orig = [2^-24, 2^6] */
#define NOISE_FLOOR_OFFSET  6

/* see comments in ApplyBoost() */
#define FBITS_GLIM_BOOST    24
#define FBITS_QLIM_BOOST    14

#define MAX_HUFF_BITS       20
#define NUM_QMF_DELAY_BUFS  10
#define DELAY_SAMPS_QMFA    (NUM_QMF_DELAY_BUFS * 32)
#define DELAY_SAMPS_QMFS    (NUM_QMF_DELAY_BUFS * 128)

/* additional external symbols to name-mangle for static linking */
#define FFT32C                          STATNAME(FFT32C)
#define CalcFreqTables                  STATNAME(CalcFreqTables)
#define AdjustHighFreq                  STATNAME(AdjustHighFreq)
#define GenerateHighFreq                STATNAME(GenerateHighFreq)
#define DecodeSBREnvelope               STATNAME(DecodeSBREnvelope)
#define DecodeSBRNoise                  STATNAME(DecodeSBRNoise)
#define UncoupleSBREnvelope             STATNAME(UncoupleSBREnvelope)
#define UncoupleSBRNoise                STATNAME(UncoupleSBRNoise)
#define InvRNormalized                  STATNAME(InvRNormalized)
#define RatioPowInv                     STATNAME(RatioPowInv)
#define SqrtFix                         STATNAME(SqrtFix)
#define QMFAnalysis                     STATNAME(QMFAnalysis)
#define QMFSynthesis                    STATNAME(QMFSynthesis)
#define GetSampRateIdx                  STATNAME(GetSampRateIdx)
#define UnpackSBRHeader                 STATNAME(UnpackSBRHeader)
#define UnpackSBRSingleChannel          STATNAME(UnpackSBRSingleChannel)
#define UnpackSBRChannelPair            STATNAME(UnpackSBRChannelPair)

/* asm functions */
#define CVKernel1                       STATNAME(CVKernel1)
#define CVKernel2                       STATNAME(CVKernel2)
#define QMFAnalysisConv                 STATNAME(QMFAnalysisConv)
#define QMFSynthesisConv                STATNAME(QMFSynthesisConv)

#define k0Tab                           STATNAME(k0Tab)
#define k2Tab                           STATNAME(k2Tab)
#define goalSBTab                       STATNAME(goalSBTab)
#define huffTabSBR                      STATNAME(huffTabSBR)
#define huffTabSBRInfo                  STATNAME(huffTabSBRInfo)
#define log2Tab                         STATNAME(log2Tab)
#define noiseTab                        STATNAME(noiseTab)
#define cTabA                           STATNAME(cTabA)
#define cTabS                           STATNAME(cTabS)

/* do y <<= n, clipping to range [-2^30, 2^30 - 1] (i.e. output has one guard bit) */
#define CLIP_2N_SHIFT30(y, n) { \
    int sign = (y) >> 31;  \
    if (sign != (y) >> (30 - (n)))  { \
        (y) = sign ^ (0x3fffffff); \
    } else { \
        (y) = (y) << (n); \
    } \
}

#define CLIP_2N(y, n) { \
    int sign = (y) >> 31;  \
    if (sign != ((y) >> (n)))  { \
        (y) = sign ^ ((1 << (n)) - 1); \
    } \
}

enum {
    SBR_GRID_FIXFIX = 0,
    SBR_GRID_FIXVAR = 1,
    SBR_GRID_VARFIX = 2,
    SBR_GRID_VARVAR = 3
};

enum {
    HuffTabSBR_tEnv15 =    0,
    HuffTabSBR_fEnv15 =    1,
    HuffTabSBR_tEnv15b =   2,
    HuffTabSBR_fEnv15b =   3,
    HuffTabSBR_tEnv30 =    4,
    HuffTabSBR_fEnv30 =    5,
    HuffTabSBR_tEnv30b =   6,
    HuffTabSBR_fEnv30b =   7,
    HuffTabSBR_tNoise30 =  8,
    HuffTabSBR_fNoise30 =  5,
    HuffTabSBR_tNoise30b = 9,
    HuffTabSBR_fNoise30b = 7
};

typedef struct _HuffInfo {
    int maxBits;                            /* number of bits in longest codeword */
    unsigned char count[MAX_HUFF_BITS];     /* count[i] = number of codes with length i+1 bits */
    int offset;                             /* offset into symbol table */
} HuffInfo;

/* need one SBRHeader per element (SCE/CPE), updated only on new header */
typedef struct _SBRHeader {
    int                   count;

    unsigned char         ampRes;
    unsigned char         startFreq;
    unsigned char         stopFreq;
    unsigned char         crossOverBand;
    unsigned char         resBitsHdr;
    unsigned char         hdrExtra1;
    unsigned char         hdrExtra2;

    unsigned char         freqScale;
    unsigned char         alterScale;
    unsigned char         noiseBands;
    
    unsigned char         limiterBands;
    unsigned char         limiterGains;
    unsigned char         interpFreq;
    unsigned char         smoothMode;
} SBRHeader;

/* need one SBRGrid per channel, updated every frame */
typedef struct _SBRGrid {
    unsigned char         frameClass;
    unsigned char         ampResFrame;
    unsigned char         pointer;

    unsigned char         numEnv;                       /* L_E */
    unsigned char         envTimeBorder[MAX_NUM_ENV+1]; /* t_E */
    unsigned char         freqRes[MAX_NUM_ENV];         /* r */

    unsigned char         numNoiseFloors;                           /* L_Q */
    unsigned char         noiseTimeBorder[MAX_NUM_NOISE_FLOORS+1];  /* t_Q */

    unsigned char         numEnvPrev;
    unsigned char         numNoiseFloorsPrev;
    unsigned char         freqResPrev;
} SBRGrid;

/* need one SBRFreq per element (SCE/CPE/LFE), updated only on header reset */
typedef struct _SBRFreq {
    int                   kStart;               /* k_x */
    int                   nMaster;
    int                   nHigh;
    int                   nLow;
    int                   nLimiter;             /* N_l */
    int                   numQMFBands;          /* M */
    int                   numNoiseFloorBands;   /* Nq */

    int                   kStartPrev;
    int                   numQMFBandsPrev;

    unsigned char         freqMaster[MAX_QMF_BANDS + 1];    /* not necessary to save this  after derived tables are generated */
    unsigned char         freqHigh[MAX_QMF_BANDS + 1];
    unsigned char         freqLow[MAX_QMF_BANDS / 2 + 1];   /* nLow = nHigh - (nHigh >> 1) */
    unsigned char         freqNoise[MAX_NUM_NOISE_FLOOR_BANDS+1];
    unsigned char         freqLimiter[MAX_QMF_BANDS / 2 + MAX_NUM_PATCHES];     /* max (intermediate) size = nLow + numPatches - 1 */

    unsigned char         numPatches;
    unsigned char         patchNumSubbands[MAX_NUM_PATCHES + 1];
    unsigned char         patchStartSubband[MAX_NUM_PATCHES + 1];
} SBRFreq;

typedef struct _SBRChan {
    int                   reset;
    unsigned char         deltaFlagEnv[MAX_NUM_ENV];
    unsigned char         deltaFlagNoise[MAX_NUM_NOISE_FLOORS];

    signed char           envDataQuant[MAX_NUM_ENV][MAX_QMF_BANDS];     /* range = [0, 127] */
    signed char           noiseDataQuant[MAX_NUM_NOISE_FLOORS][MAX_NUM_NOISE_FLOOR_BANDS];

    unsigned char         invfMode[2][MAX_NUM_NOISE_FLOOR_BANDS];   /* invfMode[0/1][band] = prev/curr */
    int                   chirpFact[MAX_NUM_NOISE_FLOOR_BANDS];     /* bwArray */
    unsigned char         addHarmonicFlag[2];                       /* addHarmonicFlag[0/1] = prev/curr */
    unsigned char         addHarmonic[2][64];                       /* addHarmonic[0/1][band] = prev/curr */
    
    int                   gbMask[2];    /* gbMask[0/1] = XBuf[0-31]/XBuf[32-39] */
    signed char           laPrev;

    int                   noiseTabIndex;
    int                   sinIndex;
    int                   gainNoiseIndex;
    int                   gTemp[MAX_NUM_SMOOTH_COEFS][MAX_QMF_BANDS];
    int                   qTemp[MAX_NUM_SMOOTH_COEFS][MAX_QMF_BANDS];

} SBRChan;

typedef struct _PSInfoSBR {
    /* save for entire file */
    int                   frameCount;
    int                   sampRateIdx;

    /* state info that must be saved for each channel */
    SBRHeader             sbrHdr[AAC_MAX_NCHANS];
    SBRGrid               sbrGrid[AAC_MAX_NCHANS];
    SBRFreq               sbrFreq[AAC_MAX_NCHANS];
    SBRChan               sbrChan[AAC_MAX_NCHANS];

    /* temp variables, no need to save between blocks */
    unsigned char         dataExtra;
    unsigned char         resBitsData;
    unsigned char         extendedDataPresent;
    int                   extendedDataSize;

    signed char           envDataDequantScale[MAX_NCHANS_ELEM][MAX_NUM_ENV];
    int                   envDataDequant[MAX_NCHANS_ELEM][MAX_NUM_ENV][MAX_QMF_BANDS];
    int                   noiseDataDequant[MAX_NCHANS_ELEM][MAX_NUM_NOISE_FLOORS][MAX_NUM_NOISE_FLOOR_BANDS];

    int                   eCurr[MAX_QMF_BANDS];
    unsigned char         eCurrExp[MAX_QMF_BANDS];
    unsigned char         eCurrExpMax;
    signed char           la;

    int                   crcCheckWord;
    int                   couplingFlag;
    int                   envBand;
    int                   eOMGainMax;
    int                   gainMax;
    int                   gainMaxFBits;
    int                   noiseFloorBand;
    int                   qp1Inv;
    int                   qqp1Inv;
    int                   sMapped;
    int                   sBand;
    int                   highBand;

    int                   sumEOrigMapped;
    int                   sumECurrGLim;
    int                   sumSM;
    int                   sumQM;
    int                   gLimBoost[MAX_QMF_BANDS];
    int                   qmLimBoost[MAX_QMF_BANDS];
    int                   smBoost[MAX_QMF_BANDS];

    int                   smBuf[MAX_QMF_BANDS];
    int                   qmLimBuf[MAX_QMF_BANDS];
    int                   gLimBuf[MAX_QMF_BANDS];
    int                   gLimFbits[MAX_QMF_BANDS];

    int                   gFiltLast[MAX_QMF_BANDS];
    int                   qFiltLast[MAX_QMF_BANDS];

    /* large buffers */
    int                   delayIdxQMFA[AAC_MAX_NCHANS];
    int                   delayQMFA[AAC_MAX_NCHANS][DELAY_SAMPS_QMFA];
    int                   delayIdxQMFS[AAC_MAX_NCHANS];
    int                   delayQMFS[AAC_MAX_NCHANS][DELAY_SAMPS_QMFS];
    int                   XBufDelay[AAC_MAX_NCHANS][HF_GEN][64][2];
    int                   XBuf[32+8][64][2];

} PSInfoSBR;

/* aacsbrfft.c */
void FFT32C(int *x);

/* aacsbrfreq.c */
int CalcFreqTables(SBRHeader *sbrHdr, SBRFreq *sbrFreq, int sampRateIdx);

/* aacsbrhfadj.c */
void AdjustHighFreq(PSInfoSBR *psi, SBRHeader *sbrHdr, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChan, int ch);

/* aacsbrhfgen.c */
void GenerateHighFreq(PSInfoSBR *psi, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChan, int ch);

/* aacsbrhuff.c */
void DecodeSBREnvelope(BitStreamInfo *bsi, PSInfoSBR *psi, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChan, int ch);
void DecodeSBRNoise(BitStreamInfo *bsi, PSInfoSBR *psi, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChan, int ch);
void UncoupleSBREnvelope(PSInfoSBR *psi, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChanR);
void UncoupleSBRNoise(PSInfoSBR *psi, SBRGrid *sbrGrid, SBRFreq *sbrFreq, SBRChan *sbrChanR);

/* aacsbrmath.c */
int InvRNormalized(int r);
int RatioPowInv(int a, int b, int c);
int SqrtFix(int x, int fBitsIn, int *fBitsOut);

/* aacsbrqmf.c */
int QMFAnalysis(int *inbuf, int *delay, int *XBuf, int fBitsIn, int *delayIdx, int qmfaBands);
void QMFSynthesis(int *inbuf, int *delay, int *delayIdx, int qmfsBands, short *outbuf, int nChans);

/* aacsbrside.c */
int GetSampRateIdx(int sampRate);
int UnpackSBRHeader(BitStreamInfo *bsi, SBRHeader *sbrHdr);
void UnpackSBRSingleChannel(BitStreamInfo *bsi, PSInfoSBR *psi, int chOut);
void UnpackSBRChannelPair(BitStreamInfo *bsi, PSInfoSBR *psi, int chOut);

/* aacsbrtabs.c */
extern const unsigned char k0Tab[NUM_SAMPLE_RATES_SBR][16];
extern const unsigned char k2Tab[NUM_SAMPLE_RATES_SBR][14];
extern const unsigned char goalSBTab[NUM_SAMPLE_RATES_SBR];
extern const HuffInfo huffTabSBRInfo[10];
extern const signed short huffTabSBR[604];
extern const int log2Tab[65];
extern const int noiseTab[512*2];
extern const int cTabA[165];
extern const int cTabS[640];

#endif  /* _SBR_H */