coder.h
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- /* ***** BEGIN LICENSE BLOCK *****
- * Version: RCSL 1.0/RPSL 1.0
- *
- * Portions Copyright (c) 1995-2002 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file, are
- * subject to the current version of the RealNetworks Public Source License
- * Version 1.0 (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the RealNetworks Community Source License Version 1.0
- * (the "RCSL") available at http://www.helixcommunity.org/content/rcsl,
- * in which case the RCSL will apply. You may also obtain the license terms
- * directly from RealNetworks. You may not use this file except in
- * compliance with the RPSL or, if you have a valid RCSL with RealNetworks
- * applicable 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 portions
- * it created.
- *
- * This file, and the files included with this file, is distributed and made
- * available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- /**************************************************************************************
- * Fixed-point MP3 decoder
- * Jon Recker (jrecker@real.com), Ken Cooke (kenc@real.com)
- * June 2003
- *
- * coder.h - private, implementation-specific header file
- **************************************************************************************/
- #ifndef _CODER_H
- #define _CODER_H
- #include "mp3common.h"
- #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
- #ifndef MAX
- #define MAX(a,b) ((a) > (b) ? (a) : (b))
- #endif
- #ifndef MIN
- #define MIN(a,b) ((a) < (b) ? (a) : (b))
- #endif
- /* clip to range [-2^n, 2^n - 1] */
- #define CLIP_2N(y, n) {
- int sign = (y) >> 31;
- if (sign != (y) >> (n)) {
- (y) = sign ^ ((1 << (n)) - 1);
- }
- }
- #define SIBYTES_MPEG1_MONO 17
- #define SIBYTES_MPEG1_STEREO 32
- #define SIBYTES_MPEG2_MONO 9
- #define SIBYTES_MPEG2_STEREO 17
- /* number of fraction bits for pow43Tab (see comments there) */
- #define POW43_FRACBITS_LOW 22
- #define POW43_FRACBITS_HIGH 12
- #define DQ_FRACBITS_OUT 25 /* number of fraction bits in output of dequant */
- #define IMDCT_SCALE 2 /* additional scaling (by sqrt(2)) for fast IMDCT36 */
- #define HUFF_PAIRTABS 32
- #define BLOCK_SIZE 18
- #define NBANDS 32
- #define MAX_REORDER_SAMPS ((192-126)*3) /* largest critical band for short blocks (see sfBandTable) */
- #define VBUF_LENGTH (17 * 2 * NBANDS) /* for double-sized vbuf FIFO */
- /* additional external symbols to name-mangle for static linking */
- #define SetBitstreamPointer STATNAME(SetBitstreamPointer)
- #define GetBits STATNAME(GetBits)
- #define CalcBitsUsed STATNAME(CalcBitsUsed)
- #define DequantChannel STATNAME(DequantChannel)
- #define MidSideProc STATNAME(MidSideProc)
- #define IntensityProcMPEG1 STATNAME(IntensityProcMPEG1)
- #define IntensityProcMPEG2 STATNAME(IntensityProcMPEG2)
- #define PolyphaseMono STATNAME(PolyphaseMono)
- #define PolyphaseStereo STATNAME(PolyphaseStereo)
- #define FDCT32 STATNAME(FDCT32)
- #define ISFMpeg1 STATNAME(ISFMpeg1)
- #define ISFMpeg2 STATNAME(ISFMpeg2)
- #define ISFIIP STATNAME(ISFIIP)
- #define uniqueIDTab STATNAME(uniqueIDTab)
- #define coef32 STATNAME(coef32)
- #define polyCoef STATNAME(polyCoef)
- #define csa STATNAME(csa)
- #define imdctWin STATNAME(imdctWin)
- #define huffTable STATNAME(huffTable)
- #define huffTabOffset STATNAME(huffTabOffset)
- #define huffTabLookup STATNAME(huffTabLookup)
- #define quadTable STATNAME(quadTable)
- #define quadTabOffset STATNAME(quadTabOffset)
- #define quadTabMaxBits STATNAME(quadTabMaxBits)
- /* map these to the corresponding 2-bit values in the frame header */
- typedef enum {
- Stereo = 0x00, /* two independent channels, but L and R frames might have different # of bits */
- Joint = 0x01, /* coupled channels - layer III: mix of M-S and intensity, Layers I/II: intensity and direct coding only */
- Dual = 0x02, /* two independent channels, L and R always have exactly 1/2 the total bitrate */
- Mono = 0x03 /* one channel */
- } StereoMode;
- typedef struct _BitStreamInfo {
- unsigned char *bytePtr;
- unsigned int iCache;
- int cachedBits;
- int nBytes;
- } BitStreamInfo;
- typedef struct _FrameHeader {
- MPEGVersion ver; /* version ID */
- int layer; /* layer index (1, 2, or 3) */
- int crc; /* CRC flag: 0 = disabled, 1 = enabled */
- int brIdx; /* bitrate index (0 - 15) */
- int srIdx; /* sample rate index (0 - 2) */
- int paddingBit; /* padding flag: 0 = no padding, 1 = single pad byte */
- int privateBit; /* unused */
- StereoMode sMode; /* mono/stereo mode */
- int modeExt; /* used to decipher joint stereo mode */
- int copyFlag; /* copyright flag: 0 = no, 1 = yes */
- int origFlag; /* original flag: 0 = copy, 1 = original */
- int emphasis; /* deemphasis mode */
- int CRCWord; /* CRC word (16 bits, 0 if crc not enabled) */
- const SFBandTable *sfBand;
- } FrameHeader;
- typedef struct _SideInfoSub {
- int part23Length; /* number of bits in main data */
- int nBigvals; /* 2x this = first set of Huffman cw's (maximum amplitude can be > 1) */
- int globalGain; /* overall gain for dequantizer */
- int sfCompress; /* unpacked to figure out number of bits in scale factors */
- int winSwitchFlag; /* window switching flag */
- int blockType; /* block type */
- int mixedBlock; /* 0 = regular block (all short or long), 1 = mixed block */
- int tableSelect[3]; /* index of Huffman tables for the big values regions */
- int subBlockGain[3]; /* subblock gain offset, relative to global gain */
- int region0Count; /* 1+region0Count = num scale factor bands in first region of bigvals */
- int region1Count; /* 1+region1Count = num scale factor bands in second region of bigvals */
- int preFlag; /* for optional high frequency boost */
- int sfactScale; /* scaling of the scalefactors */
- int count1TableSelect; /* index of Huffman table for quad codewords */
- } SideInfoSub;
- typedef struct _SideInfo {
- int mainDataBegin;
- int privateBits;
- int scfsi[MAX_NCHAN][MAX_SCFBD]; /* 4 scalefactor bands per channel */
-
- SideInfoSub sis[MAX_NGRAN][MAX_NCHAN];
- } SideInfo;
- typedef struct {
- int cbType; /* pure long = 0, pure short = 1, mixed = 2 */
- int cbEndS[3]; /* number nonzero short cb's, per subbblock */
- int cbEndSMax; /* max of cbEndS[] */
- int cbEndL; /* number nonzero long cb's */
- } CriticalBandInfo;
- typedef struct _DequantInfo {
- int workBuf[MAX_REORDER_SAMPS]; /* workbuf for reordering short blocks */
- CriticalBandInfo cbi[MAX_NCHAN]; /* filled in dequantizer, used in joint stereo reconstruction */
- } DequantInfo;
- typedef struct _HuffmanInfo {
- int huffDecBuf[MAX_NCHAN][MAX_NSAMP]; /* used both for decoded Huffman values and dequantized coefficients */
- int nonZeroBound[MAX_NCHAN]; /* number of coeffs in huffDecBuf[ch] which can be > 0 */
- int gb[MAX_NCHAN]; /* minimum number of guard bits in huffDecBuf[ch] */
- } HuffmanInfo;
- typedef enum _HuffTabType {
- noBits,
- oneShot,
- loopNoLinbits,
- loopLinbits,
- quadA,
- quadB,
- invalidTab
- } HuffTabType;
- typedef struct _HuffTabLookup {
- int linBits;
- HuffTabType tabType;
- } HuffTabLookup;
- typedef struct _IMDCTInfo {
- int outBuf[MAX_NCHAN][BLOCK_SIZE][NBANDS]; /* output of IMDCT */
- int overBuf[MAX_NCHAN][MAX_NSAMP / 2]; /* overlap-add buffer (by symmetry, only need 1/2 size) */
- int numPrevIMDCT[MAX_NCHAN]; /* how many IMDCT's calculated in this channel on prev. granule */
- int prevType[MAX_NCHAN];
- int prevWinSwitch[MAX_NCHAN];
- int gb[MAX_NCHAN];
- } IMDCTInfo;
- typedef struct _BlockCount {
- int nBlocksLong;
- int nBlocksTotal;
- int nBlocksPrev;
- int prevType;
- int prevWinSwitch;
- int currWinSwitch;
- int gbIn;
- int gbOut;
- } BlockCount;
- /* max bits in scalefactors = 5, so use char's to save space */
- typedef struct _ScaleFactorInfoSub {
- char l[23]; /* [band] */
- char s[13][3]; /* [band][window] */
- } ScaleFactorInfoSub;
- /* used in MPEG 2, 2.5 intensity (joint) stereo only */
- typedef struct _ScaleFactorJS {
- int intensityScale;
- int slen[4];
- int nr[4];
- } ScaleFactorJS;
- typedef struct _ScaleFactorInfo {
- ScaleFactorInfoSub sfis[MAX_NGRAN][MAX_NCHAN];
- ScaleFactorJS sfjs;
- } ScaleFactorInfo;
- /* NOTE - could get by with smaller vbuf if memory is more important than speed
- * (in Subband, instead of replicating each block in FDCT32 you would do a memmove on the
- * last 15 blocks to shift them down one, a hardware style FIFO)
- */
- typedef struct _SubbandInfo {
- int vbuf[MAX_NCHAN * VBUF_LENGTH]; /* vbuf for fast DCT-based synthesis PQMF - double size for speed (no modulo indexing) */
- int vindex; /* internal index for tracking position in vbuf */
- } SubbandInfo;
- /* bitstream.c */
- void SetBitstreamPointer(BitStreamInfo *bsi, int nBytes, unsigned char *buf);
- unsigned int GetBits(BitStreamInfo *bsi, int nBits);
- int CalcBitsUsed(BitStreamInfo *bsi, unsigned char *startBuf, int startOffset);
- /* dequant.c, dqchan.c, stproc.c */
- int DequantChannel(int *sampleBuf, int *workBuf, int *nonZeroBound, FrameHeader *fh, SideInfoSub *sis,
- ScaleFactorInfoSub *sfis, CriticalBandInfo *cbi);
- void MidSideProc(int x[MAX_NCHAN][MAX_NSAMP], int nSamps, int mOut[2]);
- void IntensityProcMPEG1(int x[MAX_NCHAN][MAX_NSAMP], int nSamps, FrameHeader *fh, ScaleFactorInfoSub *sfis,
- CriticalBandInfo *cbi, int midSideFlag, int mixFlag, int mOut[2]);
- void IntensityProcMPEG2(int x[MAX_NCHAN][MAX_NSAMP], int nSamps, FrameHeader *fh, ScaleFactorInfoSub *sfis,
- CriticalBandInfo *cbi, ScaleFactorJS *sfjs, int midSideFlag, int mixFlag, int mOut[2]);
- /* dct32.c */
- void FDCT32(int *x, int *d, int offset, int oddBlock, int gb);
- /* hufftabs.c */
- extern const HuffTabLookup huffTabLookup[HUFF_PAIRTABS];
- extern const int huffTabOffset[HUFF_PAIRTABS];
- extern const unsigned short huffTable[];
- extern const unsigned char quadTable[64+16];
- extern const int quadTabOffset[2];
- extern const int quadTabMaxBits[2];
- /* polyphase.c (or asmpoly.s)
- * some platforms require a C++ compile of all source files,
- * so if we're compiling C as C++ and using native assembly
- * for these functions we need to prevent C++ name mangling.
- */
- #ifdef __cplusplus
- extern "C" {
- #endif
- void PolyphaseMono(short *pcm, int *vbuf, const int *coefBase);
- void PolyphaseStereo(short *pcm, int *vbuf, const int *coefBase);
- #ifdef __cplusplus
- }
- #endif
- /* trigtabs.c */
- extern const int imdctWin[4][36];
- extern const int ISFMpeg1[2][7];
- extern const int ISFMpeg2[2][2][16];
- extern const int ISFIIP[2][2];
- extern const int csa[8][2];
- extern const int coef32[31];
- extern const int polyCoef[264];
- #endif /* _CODER_H */