Sample Code
Windows Driver Samples/ Msgsm610 Sample Codec/ C++/ gsm610.c/
//==========================================================================;
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
// KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
// PURPOSE.
//
// Copyright (c) 1993-1999 Microsoft Corporation
//
//--------------------------------------------------------------------------;
//
// gsm610.c
//
// Description:
// This file contains encode and decode routines for the
// GSM 06.10 standard.
//
//==========================================================================;
#include <windows.h>
#include <windowsx.h>
#include <mmsystem.h>
#include <mmreg.h>
#include <msacm.h>
#include <msacmdrv.h>
#include "codec.h"
#include "gsm610.h"
#include "debug.h"
#pragma warning(disable: 4213)// nonstandard extension used : cast on l-value
typedef BYTE HUGE *HPBYTE;
#ifdef WIN32
typedef WORD UNALIGNED *HPWORD;
#else
typedef WORD HUGE *HPWORD;
#endif
//**************************************************************************
/*
This source module has the following structure.
Section 1:
Highest level functions. These functions are called from outside
this module.
Section 2:
Encoding support functions. These functions support
the encoding process.
Section 3:
Decoding support functions. These functions support
the decoding process.
Section 4:
Math functions used by any of the above functions.
Most of the encode and decode support routines are direct implementations of
the pseudocode algorithms described in the GSM 6.10 specification. Some
changes were made where necessary or where optimization was obvious or
necessary.
Most variables are named as in the GSM 6.10 spec, departing from the common
hungarian notation. This facilitates referencing the specification when
studying this implementation.
Some of the functions are conditionally compiled per the definition of
the WIN32 and _X86_ symbol. These functions have analogous alternate
implementations in 80386 assembler (in GSM61016.ASM and GSM61032.ASM) for
the purposes of execution speed. The 'C' implementations of these functions
are left intact for portability and can also be referenced when studying the
assembler implementations. Symbols accessed in/from GSM610xx.ASM are
declared with the EXTERN_C linkage macro.
*/
//**************************************************************************
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//
// Typedefs
//
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
#ifndef LPSHORT
typedef SHORT FAR *LPSHORT;
#endif
//
// XM is an RPE sequence containing 13 samples. There is one
// RPE sequence per sub-frame. This is typedefed in order to
// facilitate passing the array thru function calls.
//
typedef SHORT XM[13];
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//
// Macros
//
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
#define BITSHIFTLEFT(x,c) ( ((c)>=0) ? ((x)<<(c)) : ((x)>>(-(c))) )
#define BITSHIFTRIGHT(x,c) ( ((c)>=0) ? ((x)>>(c)) : ((x)<<(-(c))) )
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//
// function protos
//
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//
//
// Math function protos
//
__inline SHORT add(SHORT var1, SHORT var2);
__inline SHORT sub(SHORT var1, SHORT var2);
__inline SHORT mult(SHORT var1, SHORT var2);
__inline SHORT mult_r(SHORT var1, SHORT var2);
__inline SHORT gabs(SHORT var1);
__inline SHORT gdiv(SHORT var1, SHORT var2);
__inline LONG l_mult(SHORT var1, SHORT var2);
__inline LONG l_add(LONG l_var1, LONG l_var2);
__inline LONG l_sub(LONG l_var1, LONG l_var2);
__inline SHORT norm(LONG l_var1);
__inline LONG IsNeg(LONG x);
//
// helper functions
//
__inline SHORT Convert8To16BitPCM(BYTE);
__inline BYTE Convert16To8BitPCM(SHORT);
//
//
// encode functions
//
void encodePreproc
( PSTREAMINSTANCE psi,
LPSHORT sop,
LPSHORT s );
void encodeLPCAnalysis
( PSTREAMINSTANCE psi,
LPSHORT s,
LPSHORT LARc );
void encodeLPCFilter
( PSTREAMINSTANCE psi,
LPSHORT LARc,
LPSHORT s,
LPSHORT d );
EXTERN_C void encodeLTPAnalysis
( PSTREAMINSTANCE psi,
LPSHORT d,
LPSHORT pNc,
LPSHORT pbc );
void encodeLTPFilter
( PSTREAMINSTANCE psi,
SHORT bc,
_In_range_(40,120) SHORT Nc,
_In_reads_(40) LPSHORT d,
_Out_writes_(40) LPSHORT e,
_Out_writes_(40) LPSHORT dpp );
void encodeRPE
( PSTREAMINSTANCE psi,
LPSHORT e,
LPSHORT pMc,
LPSHORT pxmaxc,
LPSHORT xMc,
LPSHORT ep );
void encodeUpdate
( PSTREAMINSTANCE psi,
LPSHORT ep,
LPSHORT dpp );
void PackFrame0
( BYTE FAR ab[],
SHORT FAR LAR[],
SHORT FAR N[],
SHORT FAR b[],
SHORT FAR M[],
SHORT FAR Xmax[],
XM FAR X[] );
void PackFrame1
( BYTE FAR ab[],
SHORT FAR LAR[],
SHORT FAR N[],
SHORT FAR b[],
SHORT FAR M[],
SHORT FAR Xmax[],
XM FAR X[] );
//
//
// decode functions
//
void decodeRPE
( PSTREAMINSTANCE psi,
SHORT Mcr,
SHORT xmaxcr,
LPSHORT xMcr,
LPSHORT erp );
EXTERN_C void decodeLTP
( PSTREAMINSTANCE psi,
SHORT bcr,
SHORT Ncr,
LPSHORT erp );
void decodeLPC
( PSTREAMINSTANCE psi,
LPSHORT LARcr,
LPSHORT wt,
LPSHORT sr );
EXTERN_C void decodePostproc
( PSTREAMINSTANCE psi,
_In_reads_(160) LPSHORT sr,
_Out_writes_(160) LPSHORT srop );
void UnpackFrame0
( _In_reads_(65) BYTE FAR ab[],
_Out_writes_(9) SHORT FAR LAR[],
_Out_writes_(4) SHORT FAR N[],
_Out_writes_(4) SHORT FAR b[],
_Out_writes_(4) SHORT FAR M[],
_Out_writes_(4) SHORT FAR Xmax[],
XM FAR X[] );
void UnpackFrame1
( _In_reads_(65) BYTE FAR ab[],
_Out_writes_(9) SHORT FAR LAR[],
_Out_writes_(4) SHORT FAR N[],
_Out_writes_(4) SHORT FAR b[],
_Out_writes_(4) SHORT FAR M[],
_Out_writes_(4) SHORT FAR Xmax[],
XM FAR X[] );
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// Functions
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// gsm610Reset(PSTREAMINSTANCE psi)
//
// Description:
// Resets the gsm610-specific stream instance data for
// the encode/decode routines
//
// Arguments:
// PSTREAMINSTANCE psi
// Pointer to stream instance structure
//
// Return value:
// void
// No return value
//
//---------------------------------------------------------------------
void FNGLOBAL gsm610Reset(PSTREAMINSTANCE psi)
{
// For our gsm610 codec, almost all our instance data resets to 0
UINT i;
for (i=0; i<SIZEOF_ARRAY(psi->dp); i++) psi->dp[i] = 0;
for (i=0; i<SIZEOF_ARRAY(psi->drp); i++) psi->drp[i] = 0;
psi->z1 = 0;
psi->l_z2 = 0;
psi->mp = 0;
for (i=0; i<SIZEOF_ARRAY(psi->OldLARpp); i++) psi->OldLARpp[i] = 0;
for (i=0; i<SIZEOF_ARRAY(psi->u); i++) psi->u[i] = 0;
psi->nrp = 40; // The only non-zero init
for (i=0; i<SIZEOF_ARRAY(psi->OldLARrpp); i++) psi->OldLARrpp[i] = 0;
psi->msr = 0;
for (i=0; i<SIZEOF_ARRAY(psi->v); i++) psi->v[i] = 0;
return;
}
//--------------------------------------------------------------------------;
//
// LRESULT gsm610Encode
//
// Description:
// This function handles the ACMDM_STREAM_CONVERT message. This is the
// whole purpose of writing an ACM driver--to convert data. This message
// is sent after a stream has been opened (the driver receives and
// succeeds the ACMDM_STREAM_OPEN message).
//
// Arguments:
// LPACMDRVSTREAMINSTANCE padsi: Pointer to instance data for the
// conversion stream. This structure was allocated by the ACM and
// filled with the most common instance data needed for conversions.
// The information in this structure is exactly the same as it was
// during the ACMDM_STREAM_OPEN message--so it is not necessary
// to re-verify the information referenced by this structure.
//
// LPACMDRVSTREAMHEADER padsh: Pointer to stream header structure
// that defines the source data and destination buffer to convert.
//
// Return (LRESULT):
// The return value is zero (MMSYSERR_NOERROR) if this function
// succeeds with no errors. The return value is a non-zero error code
// if the function fails.
//
//--------------------------------------------------------------------------;
LRESULT FNGLOBAL gsm610Encode
(
LPACMDRVSTREAMINSTANCE padsi,
LPACMDRVSTREAMHEADER padsh
)
{
#if (GSM610_FRAMESPERMONOBLOCK != 2)
#error THIS WAS WRITTEN FOR 2 FRAMES PER BLOCK!!!
#endif
#if (GSM610_MAXCHANNELS > 1)
#error THIS WAS WRITTEN FOR MONO ONLY!!!
#endif
PSTREAMINSTANCE psi;
DWORD cbSrcLen;
BOOL fBlockAlign;
DWORD cb;
DWORD dwcSamples; // dw count of samples
DWORD cBlocks;
UINT i;
HPBYTE hpbSrc, hpbDst;
SHORT sop[GSM610_SAMPLESPERFRAME];
SHORT s[GSM610_SAMPLESPERFRAME];
SHORT d[GSM610_SAMPLESPERFRAME];
SHORT e[GSM610_SAMPLESPERSUBFRAME];
SHORT dpp[GSM610_SAMPLESPERSUBFRAME];
SHORT ep[GSM610_SAMPLESPERSUBFRAME];
// The GSM610 stream data:
SHORT LARc[9]; // LARc[1..8] (one array per frame)
SHORT Nc[GSM610_NUMSUBFRAMES]; // Nc (one per sub-frame)
SHORT bc[GSM610_NUMSUBFRAMES]; // bc (one per sub-frame)
SHORT Mc[GSM610_NUMSUBFRAMES]; // Mc (one per sub-frame)
SHORT xmaxc[GSM610_NUMSUBFRAMES]; // Xmaxc (one per sub-frame)
XM xMc[GSM610_NUMSUBFRAMES]; // xMc (one sequence per sub-frame)
// Temp buffer to hold a block (two frames) of packed stream data
BYTE abBlock[ GSM610_BYTESPERMONOBLOCK ];
UINT nFrame;
UINT cSamples;
#ifdef DEBUG
// ProfSetup(1000,0);
// ProfStart();
#endif
psi = (PSTREAMINSTANCE)padsi->dwDriver;
//
// If this is flagged as the first block of a conversion
// then reset the stream instance data.
//
if (0 != (ACM_STREAMCONVERTF_START & padsh->fdwConvert))
{
gsm610Reset(psi);
}
fBlockAlign = (0 != (ACM_STREAMCONVERTF_BLOCKALIGN & padsh->fdwConvert));
//
// -= encode PCM to GSM 6.10 =-
//
//
//
dwcSamples = PCM_BYTESTOSAMPLES(((LPPCMWAVEFORMAT)(padsi->pwfxSrc)), padsh->cbSrcLength);
cBlocks = dwcSamples / GSM610_SAMPLESPERMONOBLOCK;
if (!fBlockAlign)
{
//
// Add on another block to hold the fragment of
// data at the end of our source data.
//
if (0 != dwcSamples % GSM610_SAMPLESPERMONOBLOCK)
cBlocks++;
}
//
//
//
cb = cBlocks * GSM610_BLOCKALIGNMENT(padsi->pwfxDst);
if (cb > padsh->cbDstLength)
{
return(ACMERR_NOTPOSSIBLE);
}
padsh->cbDstLengthUsed = cb;
if (fBlockAlign)
{
dwcSamples = cBlocks * GSM610_SAMPLESPERMONOBLOCK;
cb = PCM_SAMPLESTOBYTES(((LPPCMWAVEFORMAT)(padsi->pwfxSrc)), dwcSamples);
} else
{
cb = padsh->cbSrcLength;
}
padsh->cbSrcLengthUsed = cb;
//
//
//
cbSrcLen = padsh->cbSrcLengthUsed;
// Setup huge pointers to our src and dst buffers
hpbSrc = (HPBYTE)padsh->pbSrc;
hpbDst = (HPBYTE)padsh->pbDst;
// Loop thru entire source buffer
while (cbSrcLen)
{
// Process source buffer as two full GSM610 frames
for (nFrame=0; nFrame < 2; nFrame++)
{
//
// the src contains 8- or 16-bit PCM. currently we only
// handle mono conversions.
//
//
// we will fill sop[] with one frame of 16-bit PCM samples
//
//
// copy min( cSrcSamplesLeft, GSM610_SAMPLESPERFRAME ) samples
// to array sop[].
//
dwcSamples = PCM_BYTESTOSAMPLES(((LPPCMWAVEFORMAT)(padsi->pwfxSrc)), cbSrcLen);
cSamples = (int) min(dwcSamples, (DWORD) GSM610_SAMPLESPERFRAME);
if (padsi->pwfxSrc->wBitsPerSample == 16)
{
// copy 16-bit samples from hpbSrc to sop
for (i=0; i < cSamples; i++)
{
sop[i] = *( ((HPWORD)hpbSrc)++ );
}
} else
{
// copy 8-bit samples from hpbSrc to 16-bit samples in sop
for (i=0; i < cSamples; i++)
{
sop[i] = Convert8To16BitPCM(*hpbSrc++);
}
}
cbSrcLen -= PCM_SAMPLESTOBYTES(((LPPCMWAVEFORMAT)(padsi->pwfxSrc)), cSamples);
// fill out sop[] with silence if necessary.
for ( ; i < GSM610_SAMPLESPERFRAME; i++)
{
sop[i] = 0;
}
//
// Encode a frame of data
//
encodePreproc(psi, sop, s);
encodeLPCAnalysis(psi, s, LARc);
encodeLPCFilter(psi, LARc, s, d);
// For each of four sub-frames
for (i=0; i<4; i++)
{
encodeLTPAnalysis(psi, &d[i*40], &Nc[i], &bc[i]);
encodeLTPFilter(psi, bc[i], Nc[i], &d[i*40], e, dpp);
encodeRPE(psi, e, &Mc[i], &xmaxc[i], xMc[i], ep);
encodeUpdate(psi, ep, dpp);
}
//
// Pack the data and store in dst buffer
//
if (nFrame == 0)
PackFrame0(abBlock, LARc, Nc, bc, Mc, xmaxc, xMc);
else
{
PackFrame1(abBlock, LARc, Nc, bc, Mc, xmaxc, xMc);
for (i=0; i<GSM610_BYTESPERMONOBLOCK; i++)
*(hpbDst++) = abBlock[i];
}
} // for (nFrame...
}
#ifdef DEBUG
// ProfStop();
#endif
return(MMSYSERR_NOERROR);
}
//--------------------------------------------------------------------------;
//
// LRESULT gsm610Decode
//
// Description:
// This function handles the ACMDM_STREAM_CONVERT message. This is the
// whole purpose of writing an ACM driver--to convert data. This message
// is sent after a stream has been opened (the driver receives and
// succeeds the ACMDM_STREAM_OPEN message).
//
// Arguments:
// LPACMDRVSTREAMINSTANCE padsi: Pointer to instance data for the
// conversion stream. This structure was allocated by the ACM and
// filled with the most common instance data needed for conversions.
// The information in this structure is exactly the same as it was
// during the ACMDM_STREAM_OPEN message--so it is not necessary
// to re-verify the information referenced by this structure.
//
// LPACMDRVSTREAMHEADER padsh: Pointer to stream header structure
// that defines the source data and destination buffer to convert.
//
// Return (LRESULT):
// The return value is zero (MMSYSERR_NOERROR) if this function
// succeeds with no errors. The return value is a non-zero error code
// if the function fails.
//
//--------------------------------------------------------------------------;
LRESULT FNGLOBAL gsm610Decode
(
LPACMDRVSTREAMINSTANCE padsi,
LPACMDRVSTREAMHEADER padsh
)
{
#if (GSM610_FRAMESPERMONOBLOCK != 2)
#error THIS WAS WRITTEN FOR 2 FRAMES PER BLOCK!!!
#endif
#if (GSM610_MAXCHANNELS > 1)
#error THIS WAS WRITTEN FOR MONO ONLY!!!
#endif
PSTREAMINSTANCE psi;
DWORD cbSrcLen;
BOOL fBlockAlign;
DWORD cb;
DWORD dwcSamples;
DWORD cBlocks;
HPBYTE hpbSrc, hpbDst;
SHORT erp[GSM610_SAMPLESPERSUBFRAME];
SHORT wt[GSM610_SAMPLESPERFRAME];
SHORT sr[GSM610_SAMPLESPERFRAME];
SHORT srop[GSM610_SAMPLESPERFRAME];
// The GSM610 stream data:
SHORT LARcr[9]; // LARc[1..8] (one array per frame)
SHORT Ncr[GSM610_NUMSUBFRAMES]; // Nc (one per sub-frame)
SHORT bcr[GSM610_NUMSUBFRAMES]; // bc (one per sub-frame)
SHORT Mcr[GSM610_NUMSUBFRAMES]; // Mc (one per sub-frame)
SHORT xmaxcr[GSM610_NUMSUBFRAMES]; // Xmaxc (one per sub-frame)
XM xMcr[GSM610_NUMSUBFRAMES]; // xMc (one sequence per sub-frame)
UINT i,j;
UINT nFrame;
// Temp buffer to hold a block (two frames) of packed stream data
BYTE abBlock[ GSM610_BYTESPERMONOBLOCK ];
#ifdef DEBUG
// ProfStart();
#endif
psi = (PSTREAMINSTANCE)padsi->dwDriver;
// If this is flagged as the first block of a conversion
// then reset the stream instance data.
if (0 != (ACM_STREAMCONVERTF_START & padsh->fdwConvert))
{
gsm610Reset(psi);
}
fBlockAlign = (0 != (ACM_STREAMCONVERTF_BLOCKALIGN & padsh->fdwConvert));
//
// -= decode GSM 6.10 to PCM =-
//
//
cb = padsh->cbSrcLength;
cBlocks = cb / GSM610_BLOCKALIGNMENT(padsi->pwfxSrc);
if (0L == cBlocks)
{
padsh->cbSrcLengthUsed = cb;
padsh->cbDstLengthUsed = 0L;
return(MMSYSERR_NOERROR);
}
//
// Compute bytes we will use in destination buffer. Carefull! Look
// out for overflow in our calculations!
//
if ((0xFFFFFFFFL / GSM610_SAMPLESPERMONOBLOCK) < cBlocks)
return(ACMERR_NOTPOSSIBLE);
dwcSamples = cBlocks * GSM610_SAMPLESPERMONOBLOCK;
if (PCM_BYTESTOSAMPLES(((LPPCMWAVEFORMAT)(padsi->pwfxDst)), 0xFFFFFFFFL) < dwcSamples)
return(ACMERR_NOTPOSSIBLE);
cb = PCM_SAMPLESTOBYTES(((LPPCMWAVEFORMAT)(padsi->pwfxDst)), dwcSamples);
if (cb > padsh->cbDstLength)
{
return(ACMERR_NOTPOSSIBLE);
}
padsh->cbDstLengthUsed = cb;
padsh->cbSrcLengthUsed = cBlocks * GSM610_BLOCKALIGNMENT(padsi->pwfxSrc);
//
//
//
cbSrcLen = padsh->cbSrcLengthUsed;
// Setup huge pointers to our src and dst buffers
hpbSrc = (HPBYTE)padsh->pbSrc;
hpbDst = (HPBYTE)padsh->pbDst;
// while at least another full block of coded data
while (cbSrcLen >= GSM610_BYTESPERMONOBLOCK)
{
// copy a block of data from stream buffer to our temp buffer
for (i=0; i<GSM610_BYTESPERMONOBLOCK; i++) abBlock[i] = *(hpbSrc++);
cbSrcLen -= GSM610_BYTESPERMONOBLOCK;
// for each of the two frames in the block
for (nFrame=0; nFrame < 2; nFrame++)
{
// Unpack data from stream
if (nFrame == 0)
UnpackFrame0(abBlock, LARcr, Ncr, bcr, Mcr, xmaxcr, xMcr);
else
UnpackFrame1(abBlock, LARcr, Ncr, bcr, Mcr, xmaxcr, xMcr);
for (i=0; i<4; i++) // for each of 4 sub-blocks
{
// reconstruct the long term residual signal erp[0..39]
// from Mcr, xmaxcr, and xMcr
decodeRPE(psi, Mcr[i], xmaxcr[i], xMcr[i], erp);
// reconstruct the short term residual signal drp[0..39]
// and also update drp[-120..-1]
decodeLTP(psi, bcr[i], Ncr[i], erp);
// accumulate the four sub-blocks of reconstructed short
// term residual signal drp[0..39] into wt[0..159]
for (j=0; j<40; j++) wt[(i*40) + j] = psi->drp[120+j];
}
// reconstruct the signal s
decodeLPC(psi, LARcr, wt, sr);
// post-process the signal s
decodePostproc(psi, sr, srop);
//
// write decoded 16-bit PCM to dst. our dst format
// may be 8- or 16-bit PCM.
//
if (padsi->pwfxDst->wBitsPerSample == 16)
{
// copy 16-bit samples from srop to hpbDst
for (j=0; j < GSM610_SAMPLESPERFRAME; j++)
{
*( ((HPWORD)hpbDst)++ ) = srop[j];
}
} else
{
// copy 16-bit samples from srop to 8-bit samples in hpbDst
for (j=0; j < GSM610_SAMPLESPERFRAME; j++)
{
*(hpbDst++) = Convert16To8BitPCM(srop[j]);
}
}
} // for (nFrame...
}
#ifdef DEBUG
// ProfStop();
#endif
return(MMSYSERR_NOERROR);
}
//=====================================================================
//=====================================================================
//
// Encode routines
//
//=====================================================================
//=====================================================================
//---------------------------------------------------------------------
//--------------------------------------------------------------------
//
// Function protos
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
EXTERN_C void CompACF(LPSHORT s, LPLONG l_ACF);
void Compr(PSTREAMINSTANCE psi, LPLONG l_ACF, LPSHORT r);
void CompLAR(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT r, _Out_writes_(9) LPSHORT LAR);
void CompLARc(PSTREAMINSTANCE psi, LPSHORT LAR, LPSHORT LARc);
void CompLARpp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARc, _Out_writes_(9) LPSHORT LARpp);
void CompLARp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARpp, _Out_writes_(9) LPSHORT LARp1, _Out_writes_(9) LPSHORT LARp2, _Out_writes_(9) LPSHORT LARp3, _Out_writes_(9) LPSHORT LARp4);
void Comprp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARp, _Out_writes_(9) LPSHORT rp);
EXTERN_C void Compd(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT rp, _In_reads_(k_end-k_start+1) LPSHORT s, _Out_writes_(k_end-k_start+1) LPSHORT d, UINT k_start, UINT k_end);
void WeightingFilter(PSTREAMINSTANCE psi, LPSHORT e, LPSHORT x);
void RPEGridSelect(PSTREAMINSTANCE psi, LPSHORT x, LPSHORT pMc, LPSHORT xM);
void APCMQuantize(PSTREAMINSTANCE psi, LPSHORT xM, LPSHORT pxmaxc, LPSHORT xMc, LPSHORT pexp, LPSHORT pmant);
void APCMInvQuantize(PSTREAMINSTANCE psi, SHORT exp, SHORT mant, _In_reads_(13) LPSHORT xMc, _Out_writes_(13) LPSHORT xMp);
void RPEGridPosition(PSTREAMINSTANCE psi, SHORT Mc, LPSHORT xMp, LPSHORT ep);
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// Global constant data
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
const SHORT BCODE A[9] = {
0, // not used
20480, 20480, 20480, 20480, 13964, 15360, 8534, 9036};
const SHORT BCODE B[9] = {
0, // not used
0, 0, 2048, -2560, 94, -1792, -341, -1144};
const SHORT BCODE MIC[9] = {
0, // not used
-32, -32, -16, -16, -8, -8, -4, -4};
const SHORT BCODE MAC[9] = {
0, // not used
31, 31, 15, 15, 7, 7, 3, 3};
const SHORT BCODE INVA[9] = {
0, // unused
13107, 13107, 13107, 13107, 19223, 17476, 31454, 29708};
EXTERN_C const SHORT BCODE DLB[4] = { 6554, 16384, 26214, 32767};
EXTERN_C const SHORT BCODE QLB[4] = { 3277, 11469, 21299, 32767};
const SHORT BCODE H[11] = { -134, -374, 0, 2054, 5741, 8192, 5741, 2054, 0, -374, -134};
const SHORT BCODE NRFAC[8] = { 29128, 26215, 23832, 21846, 20165, 18725, 17476, 16384};
const SHORT BCODE FAC[8] = { 18431, 20479, 22527, 24575, 26623, 28671, 30719, 32767};
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// Procedures
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// PackFrame0
//
//---------------------------------------------------------------------
void PackFrame0
(
BYTE FAR ab[],
SHORT FAR LAR[],
SHORT FAR N[],
SHORT FAR b[],
SHORT FAR M[],
SHORT FAR Xmax[],
XM FAR X[]
)
{
int i;
// Pack the LAR[1..8] into the first 4.5 bytes
ab[0] = (BYTE)(((LAR[1] ) & 0x3F) | ((LAR[2] << 6) & 0xC0));
ab[1] = (BYTE)(((LAR[2] >> 2) & 0x0F) | ((LAR[3] << 4) & 0xF0));
ab[2] = (BYTE)(((LAR[3] >> 4) & 0x01) | ((LAR[4] << 1) & 0x3E) | ((LAR[5] << 6) & 0xC0));
ab[3] = (BYTE)(((LAR[5] >> 2) & 0x03) | ((LAR[6] << 2) & 0x3C) | ((LAR[7] << 6) & 0xC0));
ab[4] = (BYTE)(((LAR[7] >> 2) & 0x01) | ((LAR[8] << 1) & 0x0E));
// Pack N, b, M, Xmax, and X for each of the 4 sub-frames
for (i=0; i<4; i++)
{
ab[4+i*7+0] |= ((N[i] << 4) & 0xF0);
ab[4+i*7+1] = (BYTE)(((N[i] >> 4) & 0x07) | ((b[i] << 3) & 0x18) | ((M[i] << 5) & 0x60) | ((Xmax[i] << 7) & 0x80));
ab[4+i*7+2] = (BYTE)(((Xmax[i] >> 1) & 0x1F) | ((X[i][0] << 5) & 0xE0));
ab[4+i*7+3] = (BYTE)((X[i][1] & 0x07) | ((X[i][2] << 3) & 0x38) | ((X[i][3] << 6) & 0xC0));
ab[4+i*7+4] = (BYTE)(((X[i][3] >> 2) & 0x01) | ((X[i][4] << 1) & 0x0E) | ((X[i][5] << 4) & 0x70) | ((X[i][6] << 7) & 0x80));
ab[4+i*7+5] = (BYTE)(((X[i][6] >> 1) & 0x03) | ((X[i][7] << 2) & 0x1C) | ((X[i][8] << 5) & 0xE0));
ab[4+i*7+6] = (BYTE)((X[i][9] & 0x07) | ((X[i][10] << 3) & 0x38) | ((X[i][11] << 6) & 0xC0));
ab[4+i*7+7] = (BYTE)(((X[i][11] >> 2) & 0x01) | ((X[i][12] << 1) & 0x0E));
}
return;
}
//---------------------------------------------------------------------
//
// PackFrame1
//
//---------------------------------------------------------------------
void PackFrame1
(
BYTE FAR ab[],
SHORT FAR LAR[],
SHORT FAR N[],
SHORT FAR b[],
SHORT FAR M[],
SHORT FAR Xmax[],
XM FAR X[]
)
{
int i;
// Pack the LAR[1..8] into the first 4.5 bytes, starting with the
// more significant nibble of the first byte.
ab[32] |= ((LAR[1] << 4) & 0xF0);
ab[33] = (BYTE)(((LAR[1] >> 4) & 0x03) | ((LAR[2] << 2) & 0xFC));
ab[34] = (BYTE)(((LAR[3] ) & 0x1F) | ((LAR[4] << 5) & 0xE0));
ab[35] = (BYTE)(((LAR[4] >> 3) & 0x03) | ((LAR[5] << 2) & 0x3C) | ((LAR[6] << 6) & 0xC0));
ab[36] = (BYTE)(((LAR[6] >> 2) & 0x03) | ((LAR[7] << 2) & 0x1C) | ((LAR[8] << 5) & 0xE0));
// Pack N, b, M, Xmax, and X for each of the 4 sub-frames
for (i=0; i<4; i++)
{
ab[37+i*7+0] = (BYTE)((N[i] & 0x7F) | ((b[i] << 7) & 0x80));
ab[37+i*7+1] = (BYTE)(((b[i] >> 1) & 0x01) | ((M[i] << 1) & 0x06) | ((Xmax[i] << 3) & 0xF8));
ab[37+i*7+2] = (BYTE)(((Xmax[i] >> 5) & 0x01) | ((X[i][0] << 1) & 0x0E) | ((X[i][1] << 4) & 0x70) | ((X[i][2] << 7) & 0x80));
ab[37+i*7+3] = (BYTE)(((X[i][2] >> 1) & 0x03) | ((X[i][3] << 2) & 0x1C) | ((X[i][4] << 5) & 0xE0));
ab[37+i*7+4] = (BYTE)(((X[i][5] ) & 0x07) | ((X[i][6] << 3) & 0x38) | ((X[i][7] << 6) & 0xC0));
ab[37+i*7+5] = (BYTE)(((X[i][7] >> 2) & 0x01) | ((X[i][8] << 1) & 0x0E) | ((X[i][9] << 4) & 0x70) | ((X[i][10] << 7) & 0x80));
ab[37+i*7+6] = (BYTE)(((X[i][10] >> 1) & 0x03) | ((X[i][11] << 2) & 0x1C) | ((X[i][12] << 5) & 0xE0));
}
return;
}
//---------------------------------------------------------------------
//
// encodePreproc()
//
//---------------------------------------------------------------------
void encodePreproc(PSTREAMINSTANCE psi, LPSHORT sop, LPSHORT s)
{
SHORT so[160];
SHORT sof[160];
UINT k;
SHORT s1;
SHORT temp;
SHORT msp, lsp;
LONG l_s2;
// downscale
for (k=0; k<160; k++)
{
so[k] = sop[k] >> 3;
so[k] = so[k] << 2;
}
// offset compensation
for (k=0; k<160; k++)
{
// Compute the non-recursive part
s1 = sub(so[k], psi->z1);
psi->z1 = so[k];
// compute the recursive part
l_s2 = s1;
l_s2 = l_s2 << 15;
// execution of 31 by 16 bits multiplication
msp = (SHORT) (psi->l_z2 >> 15);
lsp = (SHORT) l_sub(psi->l_z2, ( ((LONG)msp) << 15));
temp = mult_r(lsp, 32735);
l_s2 = l_add(l_s2, temp);
psi->l_z2 = l_add(l_mult(msp, 32735) >> 1, l_s2);
// compute sof[k] with rounding
sof[k] = (SHORT) (l_add(psi->l_z2, 16384) >> 15);
}
// preemphasis
for (k=0; k<160; k++)
{
s[k] = add(sof[k], mult_r(psi->mp, -28180));
psi->mp = sof[k];
}
return;
}
//---------------------------------------------------------------------
//
// encodeLPCAnalysis()
//
//---------------------------------------------------------------------
void encodeLPCAnalysis(PSTREAMINSTANCE psi, LPSHORT s, LPSHORT LARc)
{
LONG l_ACF[9];
SHORT r[9];
SHORT LAR[9];
CompACF(s, l_ACF);
Compr(psi, l_ACF, r);
CompLAR(psi, r, LAR);
CompLARc(psi, LAR, LARc);
return;
}
//---------------------------------------------------------------------
//
// CompACF()
//
//---------------------------------------------------------------------
void CompACF(LPSHORT s, LPLONG l_ACF)
{
SHORT smax, temp, scalauto;
UINT i, k;
//
// Dynamic scaling of array s[0..159]
//
// Search for the maximum
smax = 0;
for (k=0; k<160; k++)
{
temp = gabs(s[k]);
if (temp > smax) smax = temp;
}
// Computation of the scaling factor
if (smax == 0) scalauto = 0;
else scalauto = sub( 4, norm( ((LONG)smax)<<16 ) );
// Scaling of the array s
if (scalauto > 0)
{
temp = BITSHIFTRIGHT(16384, sub(scalauto,1));
for (k=0; k<160; k++)
{
// s[k] = mult_r(s[k], temp);
s[k] = HIWORD( ( (((LONG)s[k])<<(15-scalauto)) + 0x4000L ) << 1 );
}
}
//
// Compute the l_ACF[..]
//
for (k=0; k<9; k++)
{
l_ACF[k] = 0;
for (i=k; i<160; i++)
{
l_ACF[k] = l_add(l_ACF[k], l_mult(s[i], s[i-k]));
}
}
//
// Rescaling of array s
//
if (scalauto > 0)
{
for (k=0; k<160; k++)
{
// We don't need the BITSHIFTLEFT macro
// cuz we know scalauto>0 due to above test
s[k] = s[k] << scalauto;
}
}
//
//
//
return;
}
//---------------------------------------------------------------------
//
// Compr()
//
//---------------------------------------------------------------------
void Compr(PSTREAMINSTANCE psi, LPLONG l_ACF, LPSHORT r)
{
UINT i, k, m, n;
SHORT temp, ACF[9];
SHORT K[9], P[9]; // K[2..8], P[0..8]
UNREFERENCED_PARAMETER(psi);
//
// Schur recursion with 16 bits arithmetic
//
if (l_ACF[0] == 0)
{
for (i=1; i<=8; i++)
{
r[i] = 0;
}
return;
}
temp = norm(l_ACF[0]);
for (k=0; k<=8; k++)
{
ACF[k] = (SHORT) ((BITSHIFTLEFT(l_ACF[k], temp)) >> 16);
}
//
// Init array P and K for the recursion
//
for (i=1; i<=7; i++)
{
K[9-i] = ACF[i];
}
for (i=0; i<=8; i++)
{
P[i] = ACF[i];
}
//
// Compute reflection coefficients
//
for (n=1; n<=8; n++)
{
if (P[0] < gabs(P[1]))
{
for (i=n; i<=8; i++)
{
r[i] = 0;
}
return;
}
r[n] = gdiv(gabs(P[1]),P[0]);
if (P[1] > 0) r[n] = sub(0,r[n]);
// Here's the real exit from this for loop
if (n==8) return;
// Schur recursion
P[0] = add(P[0], mult_r(P[1], r[n]));
for (m=1; m<=8-n; m++)
{
P[m] = add( P[m+1], mult_r(K[9-m],r[n]) );
K[9-m] = add( K[9-m], mult_r(P[m+1], r[n]) );
}
}
}
//---------------------------------------------------------------------
//
// CompLAR()
//
// Remarks:
// The parameter annotations indicate 9 elements in the arrays. However
// the algorithm uses only elements 1..8.
//
//---------------------------------------------------------------------
void CompLAR(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT r, _Out_writes_(9) LPSHORT LAR)
{
UINT i;
SHORT temp;
UNREFERENCED_PARAMETER(psi);
//
// Computation of LAR[1..8] from r[1..8]
//
for (i=1; i<=8; i++)
{
temp = gabs(r[i]);
if (temp < 22118)
{
temp = temp >> 1;
} else if (temp < 31130)
{
temp = sub(temp, 11059);
} else
{
temp = sub(temp, 26112) << 2;
}
LAR[i] = temp;
if (r[i] < 0)
{
LAR[i] = sub(0, LAR[i]);
}
}
return;
}
//---------------------------------------------------------------------
//
// CompLARc()
//
//---------------------------------------------------------------------
void CompLARc(PSTREAMINSTANCE psi, LPSHORT LAR, LPSHORT LARc)
{
UINT i;
SHORT temp;
UNREFERENCED_PARAMETER(psi);
for (i=1; i<=8; i++)
{
temp = mult(A[i], LAR[i]);
temp = add(temp, B[i]);
temp = add(temp, 256);
LARc[i] = temp >> 9;
// Check if LARc[i] between MIN and MAX
if (LARc[i] > MAC[i]) LARc[i] = MAC[i];
if (LARc[i] < MIC[i]) LARc[i] = MIC[i];
// This is used to make all LARc positive
LARc[i] = sub(LARc[i], MIC[i]);
}
return;
}
//---------------------------------------------------------------------
//
// encodeLPCFilter()
//
//---------------------------------------------------------------------
void encodeLPCFilter(PSTREAMINSTANCE psi, LPSHORT LARc, LPSHORT s, LPSHORT d)
{
SHORT LARpp[9]; // array [1..8]
SHORT LARp1[9], LARp2[9], LARp3[9], LARp4[9]; // array [1..8]
SHORT rp[9]; // array [1..8]
CompLARpp(psi, LARc, LARpp);
CompLARp(psi, LARpp, LARp1, LARp2, LARp3, LARp4);
Comprp(psi, LARp1, rp);
Compd(psi, (LPSHORT)rp, s, d, 0, 12);
Comprp(psi, LARp2, rp);
Compd(psi, (LPSHORT)rp, s, d, 13, 26);
Comprp(psi, LARp3, rp);
Compd(psi, (LPSHORT)rp, s, d, 27, 39);
Comprp(psi, LARp4, rp);
Compd(psi, (LPSHORT)rp, s, d, 40, 159);
return;
}
//---------------------------------------------------------------------
//
// CompLARpp()
//
// Remarks:
// The parameter annotations indicate 9 elements in the arrays. However
// the algorithm uses only elements 1..8.
//
//---------------------------------------------------------------------
void CompLARpp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARc, _Out_writes_(9) LPSHORT LARpp)
{
UINT i;
SHORT temp1, temp2;
UNREFERENCED_PARAMETER(psi);
for (i=1; i<=8; i++)
{
temp1 = add(LARc[i], MIC[i]) << 10;
temp2 = B[i] << 1;
temp1 = sub(temp1,temp2);
temp1 = mult_r(INVA[i], temp1);
LARpp[i] = add(temp1, temp1);
}
return;
}
//---------------------------------------------------------------------
//
// CompLARp()
//
// Remarks:
// The parameter annotations indicate 9 elements in the arrays. However
// the algorithm uses only elements 1..8.
//
//---------------------------------------------------------------------
void CompLARp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARpp, _Out_writes_(9) LPSHORT LARp1, _Out_writes_(9) LPSHORT LARp2, _Out_writes_(9) LPSHORT LARp3, _Out_writes_(9) LPSHORT LARp4)
{
UINT i;
for (i=1; i<=8; i++)
{
LARp1[i] = add( (SHORT)(psi->OldLARpp[i] >> 2), (SHORT)(LARpp[i] >> 2) );
LARp1[i] = add( LARp1[i], (SHORT)(psi->OldLARpp[i] >> 1) );
LARp2[i] = add( (SHORT)(psi->OldLARpp[i] >> 1), (SHORT)(LARpp[i] >> 1) );
LARp3[i] = add( (SHORT)(psi->OldLARpp[i] >> 2), (SHORT)(LARpp[i] >> 2) );
LARp3[i] = add( LARp3[i], (SHORT)(LARpp[i] >> 1) );
LARp4[i] = LARpp[i];
}
for (i=1; i<=8; i++)
{
psi->OldLARpp[i] = LARpp[i];
}
return;
}
//---------------------------------------------------------------------
//
// Comprp()
//
// Remarks:
// The parameter annotations indicate 9 elements in the arrays. However
// the algorithm uses only elements 1..8.
//
//---------------------------------------------------------------------
void Comprp(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT LARp, _Out_writes_(9) LPSHORT rp)
{
UINT i;
SHORT temp;
UNREFERENCED_PARAMETER(psi);
for (i=1; i<=8; i++)
{
temp = gabs(LARp[i]);
if (temp < 11059)
{
temp = temp << 1;
} else if (temp < 20070)
{
temp = add(temp, 11059);
} else
{
temp = add((SHORT)(temp>>2), 26112);
}
rp[i] = temp;
if (LARp[i] < 0)
{
rp[i] = sub(0,rp[i]);
}
}
return;
}
//---------------------------------------------------------------------
//
// Compd()
//
// Remarks:
// The parameter annotations indicate 9 elements in the arrays. However
// the algorithm uses only elements 1..8.
//
//---------------------------------------------------------------------
void Compd(PSTREAMINSTANCE psi, _In_reads_(9) LPSHORT rp, _In_reads_(k_end-k_start+1) LPSHORT s, _Out_writes_(k_end-k_start+1) LPSHORT d, UINT k_start, UINT k_end)
{
UINT k, i;
SHORT sav;
SHORT di;
SHORT temp;
for (k=k_start; k<=k_end; k++)
{
di = s[k];
sav = di;
for (i=1; i<=8; i++)
{
temp = add( psi->u[i-1], mult_r(rp[i],di) );
di = add( di, mult_r(rp[i], psi->u[i-1]) );
psi->u[i-1] = sav;
sav = temp;
}
d[k] = di;
}
return;
}
//---------------------------------------------------------------------
//
// encodeLTPAnalysis()
//
//---------------------------------------------------------------------
void encodeLTPAnalysis(PSTREAMINSTANCE psi, LPSHORT d, LPSHORT pNc, LPSHORT pbc)
{
SHORT dmax;
SHORT temp;
SHORT scal;
SHORT wt[40];
SHORT lambda;
LONG l_max, l_power;
SHORT R, S;
SHORT Nc;
int k; // k must be int, not UINT!
Nc = *pNc;
// Search of the optimum scaling of d[0..39]
dmax = 0;
for (k=39; k>=0; k--)
{
temp = gabs( d[k] );
if (temp > dmax) dmax = temp;
}
temp = 0;
if (dmax == 0) scal = 0;
else temp = norm( ((LONG)dmax) << 16);
if (temp > 6) scal = 0;
else scal = sub(6,temp);
// Init of working array wt[0..39]
ASSERT( scal >= 0 );
for (k=39; k>=0; k--)
{
wt[k] = d[k] >> scal;
}
// Search for max cross-correlation and coding of LTP lag
l_max = 0;
Nc = 40;
for (lambda=40; lambda<=120; lambda++)
{
register LONG l_result = 0;
for (k=39; k>=0; k--)
{
l_result += (LONG)(wt[k]) * (LONG)(psi->dp[120-lambda+k]);
}
if (l_result > l_max)
{
Nc = lambda;
l_max = l_result;
}
}
l_max <<= 1; // This operation should be on l_result as part of the
// multiply/add, but for efficiency we shift it all
// the way out of the loops.
// Rescaling of l_max
ASSERT( sub(6,scal) >= 0 );
l_max = l_max >> sub(6,scal);
// Compute the power of the reconstructed short term residual
// signal dp[..].
l_power = 0;
{
SHORT s;
for (k=39; k>=0; k--)
{
s = psi->dp[120-Nc+k] >> 3;
l_power += s*s; // This sum can never overflow!!!
}
ASSERT( l_power >= 0 );
if ( l_power >= 1073741824 )
{ // 2**30
l_power = 2147483647; // 2**31 - 1
} else
{
l_power <<= 1; // This shift is normally part of l_mult().
}
}
*pNc = Nc;
// Normalization of l_max and l_power
if (l_max <= 0)
{
*pbc = 0;
return;
}
if (l_max >= l_power)
{
*pbc = 3;
return;
}
temp = norm(l_power);
ASSERT( temp >= 0 );
R = (SHORT) ((l_max<<temp) >> 16);
S = (SHORT) ((l_power<<temp) >> 16);
// Codeing of the LTP gain
for ( *pbc=0; *pbc<=2; (*pbc)++ )
{
if (R <= mult(S, DLB[*pbc]))
{
return;
}
}
*pbc = 3;
return;
}
//---------------------------------------------------------------------
//
// encodeLTPFilter()
//
//---------------------------------------------------------------------
void encodeLTPFilter(PSTREAMINSTANCE psi, SHORT bc, _In_range_(40,120) SHORT Nc, _In_reads_(40) LPSHORT d, _Out_writes_(40) LPSHORT e, _Out_writes_(40) LPSHORT dpp)
{
SHORT bp;
UINT k;
// Decoding of the coded LTP gain
bp = QLB[bc];
// Calculating the array e[0..39] and the array dpp[0..39]
for (k=0; k<=39; k++)
{
dpp[k] = mult_r(bp, psi->dp[120+k-Nc]);
e[k] = sub(d[k], dpp[k]);
}
return;
}
//---------------------------------------------------------------------
//
// encodeRPE()
//
//---------------------------------------------------------------------
void encodeRPE(PSTREAMINSTANCE psi, LPSHORT e, LPSHORT pMc, LPSHORT pxmaxc, LPSHORT xMc, LPSHORT ep)
{
SHORT x[40];
SHORT xM[13];
SHORT exp, mant;
SHORT xMp[13];
WeightingFilter(psi, e, x);
RPEGridSelect(psi, x, pMc, xM);
APCMQuantize(psi, xM, pxmaxc, xMc, &exp, &mant);
APCMInvQuantize(psi, exp, mant, xMc, xMp);
RPEGridPosition(psi, *pMc, xMp, ep);
return;
}
//---------------------------------------------------------------------
//
// WeightingFilter()
//
//---------------------------------------------------------------------
void WeightingFilter(PSTREAMINSTANCE psi, LPSHORT e, LPSHORT x)
{
UINT i, k;
LONG l_result, l_temp;
SHORT wt[50];
UNREFERENCED_PARAMETER(psi);
// Initialization of a temporary working array wt[0..49]
for (k= 0; k<= 4; k++) wt[k] = 0;
for (k= 5; k<=44; k++) wt[k] = e[k-5];
for (k=45; k<=49; k++) wt[k] = 0;
// Compute the signal x[0..39]
for (k=0; k<=39; k++)
{
l_result = 8192; // rounding of the output of the filter
for (i=0; i<=10; i++)
{
l_temp = l_mult(wt[k+i], H[i]);
l_result = l_add(l_result, l_temp);
}
l_result = l_add(l_result, l_result); // scaling x2
l_result = l_add(l_result, l_result); // scaling x4
x[k] = (SHORT) (l_result >> 16);
}
return;
}
//---------------------------------------------------------------------
//
// RPEGridSelect()
//
//---------------------------------------------------------------------
void RPEGridSelect(PSTREAMINSTANCE psi, LPSHORT x, LPSHORT pMc, LPSHORT xM)
{
UINT m, i;
LONG l_EM;
SHORT temp1;
LONG l_result, l_temp;
UNREFERENCED_PARAMETER(psi);
// the signal x[0..39] is used to select the RPE grid which is
// represented by Mc
l_EM = 0;
*pMc = 0;
for (m=0; m<=3; m++)
{
l_result = 0;
for (i=0; i<=12; i++)
{
temp1 = x[m+(3*i)] >> 2;
l_temp = l_mult(temp1, temp1);
l_result = l_add(l_temp, l_result);
}
if (l_result > l_EM)
{
*pMc = (SHORT)m;
l_EM = l_result;
}
}
// down-sampling by a factor of 3 to get the selected xM[0..12]
// RPE sequence
for (i=0; i<=12; i++)
{
xM[i] = x[*pMc + (3*i)];
}
return;
}
//---------------------------------------------------------------------
//
// APCMQuantize()
//
//---------------------------------------------------------------------
void APCMQuantize(PSTREAMINSTANCE psi, LPSHORT xM, LPSHORT pxmaxc, LPSHORT xMc, LPSHORT pexp, LPSHORT pmant)
{
UINT i;
SHORT xmax;
SHORT temp;
SHORT itest;
SHORT temp1, temp2;
UNREFERENCED_PARAMETER(psi);
// find the maximum absolute value xmax or xM[0..12]
xmax = 0;
for (i=0; i<=12; i++)
{
temp = gabs(xM[i]);
if (temp > xmax) xmax = temp;
}
// quantizing and coding of xmax to get xmaxc
*pexp = 0;
temp = xmax >> 9;
itest = 0;
for (i=0; i<=5; i++)
{
if (temp <=0) itest = 1;
temp = temp >> 1;
if (itest == 0) *pexp = add(*pexp,1);
}
temp = add(*pexp,5);
*pxmaxc = add( (SHORT)BITSHIFTRIGHT(xmax,temp), (SHORT)(*pexp << 3) );
//
// quantizing and coding of the xM[0..12] RPE sequence to get
// the xMc[0..12]
//
// compute exponent and mantissa of the decoded version of xmaxc
*pexp = 0;
if (*pxmaxc > 15) *pexp = sub((SHORT)(*pxmaxc >> 3),1);
*pmant = sub(*pxmaxc,(SHORT)(*pexp<<3));
// normalize mantissa 0 <= mant <= 7
if (*pmant==0)
{
*pexp = -4;
*pmant = 15;
} else
{
itest = 0;
for (i=0; i<=2; i++)
{
if (*pmant > 7) itest = 1;
if (itest == 0) *pmant = add((SHORT)(*pmant << 1),1);
if (itest == 0) *pexp = sub(*pexp,1);
}
}
*pmant = sub(*pmant,8);
// direct computation of xMc[0..12] using table
temp1 = sub(6,*pexp); // normalization by the exponent
temp2 = NRFAC[*pmant]; // see table (inverse mantissa)
for (i=0; i<=12; i++)
{
temp = BITSHIFTLEFT(xM[i], temp1);
temp = mult( temp, temp2 );
xMc[i] = add( (SHORT)(temp >> 12), 4 ); // makes all xMc[i] positive
}
return;
}
//---------------------------------------------------------------------
//
// APCMInvQuantize()
//
//---------------------------------------------------------------------
void APCMInvQuantize(PSTREAMINSTANCE psi, SHORT exp, SHORT mant, _In_reads_(13) LPSHORT xMc, _Out_writes_(13) LPSHORT xMp)
{
SHORT temp1, temp2, temp3, temp;
UINT i;
UNREFERENCED_PARAMETER(psi);
temp1 = FAC[mant];
temp2 = sub(6,exp);
temp3 = BITSHIFTLEFT(1, sub(temp2,1));
for (i=0; i<=12; i++)
{
temp = sub( (SHORT)(xMc[i] << 1), 7); // restores sign of xMc[i]
temp = temp << 12;
temp = mult_r(temp1, temp);
temp = add(temp, temp3);
xMp[i] = BITSHIFTRIGHT(temp,temp2);
}
return;
}
//---------------------------------------------------------------------
//
// RPEGridPosition(SHORT Mc, LPSHORT xMp, LPSHORT ep)
//
//---------------------------------------------------------------------
void RPEGridPosition(PSTREAMINSTANCE psi, SHORT Mc, LPSHORT xMp, LPSHORT ep)
{
UINT k, i;
UNREFERENCED_PARAMETER(psi);
for (k=0; k<=39; k++)
{
ep[k] = 0;
}
for (i=0; i<=12; i++)
{
ep[Mc + (3*i)] = xMp[i];
}
return;
}
//---------------------------------------------------------------------
//
// encodeUpdate()
//
//---------------------------------------------------------------------
void encodeUpdate(PSTREAMINSTANCE psi, LPSHORT ep, LPSHORT dpp)
{
UINT k;
for (k=0; k<=79; k++)
psi->dp[120-120+k] = psi->dp[120-80+k];
for (k=0; k<=39; k++)
psi->dp[120-40+k] = add(ep[k], dpp[k]);
return;
}
//=====================================================================
//=====================================================================
//
// Decode routines
//
//=====================================================================
//=====================================================================
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// Function protos
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
EXTERN_C void Compsr(PSTREAMINSTANCE psi, _In_reads_(k_end-k_start+1) LPSHORT wt, _In_reads_(9) LPSHORT rrp, UINT k_start, UINT k_end, _Out_writes_(k_end-k_start+1) LPSHORT sr);
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// Procedures
//
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//---------------------------------------------------------------------
//
// UnpackFrame0
//
// Remarks:
// The LAR parameter is annotated as 9 elements. However the algorithm
// uses only elements 1..8.
//
//---------------------------------------------------------------------
void UnpackFrame0
(
_In_reads_(65) BYTE FAR ab[],
_Out_writes_(9) SHORT FAR LAR[],
_Out_writes_(4) SHORT FAR N[],
_Out_writes_(4) SHORT FAR b[],
_Out_writes_(4) SHORT FAR M[],
_Out_writes_(4) SHORT FAR Xmax[],
XM FAR X[]
)
{
UINT i;
// Unpack the LAR[1..8] from the first 4.5 bytes
LAR[1] = (ab[0] & 0x3F);
LAR[2] = ((ab[0] & 0xC0) >> 6) | ((ab[1] & 0x0F) << 2);
LAR[3] = ((ab[1] & 0xF0) >> 4) | ((ab[2] & 0x01) << 4);
LAR[4] = ((ab[2] & 0x3E) >> 1);
LAR[5] = ((ab[2] & 0xC0) >> 6) | ((ab[3] & 0x03) << 2);
LAR[6] = ((ab[3] & 0x3C) >> 2);
LAR[7] = ((ab[3] & 0xC0) >> 6) | ((ab[4] & 0x01) << 2);
LAR[8] = ((ab[4] & 0x0E) >> 1);
// Unpack N, b, M, Xmax, and X for each of the four sub-frames
for (i=0; i<4; i++)
{
// A convenient macro for getting bytes out of the array for
// construction of the subframe parameters
#define sfb(x) (ab[4+i*7+x])
N[i] = ((sfb(0) & 0xF0) >> 4) | ((sfb(1) & 0x07) << 4);
b[i] = ((sfb(1) & 0x18) >> 3);
M[i] = ((sfb(1) & 0x60) >> 5);
Xmax[i] = ((sfb(1) & 0x80) >> 7) | ((sfb(2) & 0x1F) << 1);
X[i][0] = ((sfb(2) & 0xE0) >> 5);
X[i][1] = (sfb(3) & 0x07);
X[i][2] = ((sfb(3) & 0x3C) >> 3);
X[i][3] = ((sfb(3) & 0xC0) >> 6) | ((sfb(4) & 0x01) << 2);
X[i][4] = ((sfb(4) & 0x0E) >> 1);
X[i][5] = ((sfb(4) & 0x70) >> 4);
X[i][6] = ((sfb(4) & 0x80) >> 7) | ((sfb(5) & 0x03) << 1);
X[i][7] = ((sfb(5) & 0x1C) >> 2);
X[i][8] = ((sfb(5) & 0xE0) >> 5);
X[i][9] = (sfb(6) & 0x07);
X[i][10] = ((sfb(6) & 0x38) >> 3);
X[i][11] = ((sfb(6) & 0xC0) >> 6) | ((sfb(7) & 0x01) << 2);
X[i][12] = ((sfb(7) & 0x0E) >> 1);
#undef sfb
}
return;
}
//---------------------------------------------------------------------
//
// UnpackFrame1
//
// Remarks:
// The LAR parameter is annotated as 9 elements. However the algorithm
// uses only elements 1..8.
//
//---------------------------------------------------------------------
void UnpackFrame1
(
_In_reads_(65) BYTE FAR ab[],
_Out_writes_(9) SHORT FAR LAR[],
_Out_writes_(4) SHORT FAR N[],
_Out_writes_(4) SHORT FAR b[],
_Out_writes_(4) SHORT FAR M[],
_Out_writes_(4) SHORT FAR Xmax[],
XM FAR X[]
)
{
UINT i;
// Unpack the LAR[1..8] from the first 4.5 bytes
LAR[1] = ((ab[32] & 0xF0) >> 4) | ((ab[33] & 0x03) << 4);
LAR[2] = ((ab[33] & 0xFC) >> 2);
LAR[3] = ((ab[34] & 0x1F) );
LAR[4] = ((ab[34] & 0xE0) >> 5) | ((ab[35] & 0x03) << 3);
LAR[5] = ((ab[35] & 0x3C) >> 2);
LAR[6] = ((ab[35] & 0xC0) >> 6) | ((ab[36] & 0x03) << 2);
LAR[7] = ((ab[36] & 0x1C) >> 2);
LAR[8] = ((ab[36] & 0xE0) >> 5);
// Unpack N, b, M, Xmax, and X for each of the four sub-frames
for (i=0; i<4; i++)
{
// A convenient macro for getting bytes out of the array for
// construction of the subframe parameters
#define sfb(x) (ab[37+i*7+x])
N[i] = sfb(0) & 0x7F;
b[i] = ((sfb(0) & 0x80) >> 7) | ((sfb(1) & 0x01) << 1);
M[i] = ((sfb(1) & 0x06) >> 1);
Xmax[i] = ((sfb(1) & 0xF8) >> 3) | ((sfb(2) & 0x01) << 5);
X[i][0] = ((sfb(2) & 0x0E) >> 1);
X[i][1] = ((sfb(2) & 0x70) >> 4);
X[i][2] = ((sfb(2) & 0x80) >> 7) | ((sfb(3) & 0x03) << 1);
X[i][3] = ((sfb(3) & 0x1C) >> 2);
X[i][4] = ((sfb(3) & 0xE0) >> 5);
X[i][5] = ((sfb(4) & 0x07) );
X[i][6] = ((sfb(4) & 0x38) >> 3);
X[i][7] = ((sfb(4) & 0xC0) >> 6) | ((sfb(5) & 0x01) << 2);
X[i][8] = ((sfb(5) & 0x0E) >> 1);
X[i][9] = ((sfb(5) & 0x70) >> 4);
X[i][10] = ((sfb(5) & 0x80) >> 7) | ((sfb(6) & 0x03) << 1);
X[i][11] = ((sfb(6) & 0x1C) >> 2);
X[i][12] = ((sfb(6) & 0xE0) >> 5);
#undef sfb
}
return;
}
//---------------------------------------------------------------------
//
// decodeRPE()
//
//---------------------------------------------------------------------
void decodeRPE(PSTREAMINSTANCE psi, SHORT Mcr, SHORT xmaxcr, LPSHORT xMcr, LPSHORT erp)
{
SHORT exp, mant;
SHORT itest;
UINT i;
SHORT temp1, temp2, temp3, temp;
SHORT xMrp[13];
UINT k;
UNREFERENCED_PARAMETER(psi);
// compute the exponent and mantissa of the decoded
// version of xmaxcr
exp = 0;
if (xmaxcr > 15) exp = sub( (SHORT)(xmaxcr >> 3), 1 );
mant = sub( xmaxcr, (SHORT)(exp << 3) );
// normalize the mantissa 0 <= mant <= 7
if (mant == 0)
{
exp = -4;
mant = 15;
} else
{
itest = 0;
for (i=0; i<=2; i++)
{
if (mant > 7) itest = 1;
if (itest == 0) mant = add((SHORT)(mant << 1),1);
if (itest == 0) exp = sub(exp,1);
}
}
mant = sub(mant, 8);
// APCM inverse quantization
temp1 = FAC[mant];
temp2 = sub(6,exp);
temp3 = BITSHIFTLEFT(1, sub(temp2, 1));
for (i=0; i<=12; i++)
{
temp = sub( (SHORT)(xMcr[i] << 1), 7 );
temp = temp << 12;
temp = mult_r(temp1, temp);
temp = add(temp, temp3);
xMrp[i] = BITSHIFTRIGHT(temp, temp2);
}
// RPE grid positioning
for (k=0; k<=39; k++) erp[k] = 0;
for (i=0; i<=12; i++) erp[Mcr + (3*i)] = xMrp[i];
//
return;
}
//---------------------------------------------------------------------
//
// decodeLTP()
//
//---------------------------------------------------------------------
void decodeLTP(PSTREAMINSTANCE psi, SHORT bcr, SHORT Ncr, LPSHORT erp)
{
SHORT Nr;
SHORT brp;
UINT k;
SHORT drpp;
// check limits of Nr
Nr = Ncr;
if (Ncr < 40) Nr = psi->nrp;
if (Ncr > 120) Nr = psi->nrp;
psi->nrp = Nr;
// decoding of the LTP gain bcr
brp = QLB[bcr];
// computation of the reconstructed short term residual
// signal drp[0..39]
for (k=0; k<=39; k++)
{
drpp = mult_r( brp, psi->drp[120+k-Nr] );
psi->drp[120+k] = add( erp[k], drpp );
}
// update of the reconstructed short term residual
// signal drp[-1..-120]
for (k=0; k<=119; k++)
{
psi->drp[120-120+k] = psi->drp[120-80+k];
}
return;
}
//---------------------------------------------------------------------
//
// decodeLPC
//
//---------------------------------------------------------------------
void decodeLPC
(
PSTREAMINSTANCE psi, // instance data
LPSHORT LARcr, // received coded Log.-Area Ratios [1..8]
LPSHORT wt, // accumulated drp signal [0..159]
LPSHORT sr // reconstructed s [0..159]
)
{
UINT i;
SHORT LARrpp[9]; // LARrpp[1..8], decoded LARcr
SHORT LARrp[9]; // LARrp[1..9], interpolated LARrpp
SHORT rrp[9]; // rrp[1..8], reflection coefficients
SHORT temp1, temp2;
//
// decoding of the coded log area ratios to get LARrpp[1..8]
//
// compute LARrpp[1..8]
for (i=1; i<=8; i++)
{
temp1 = add( LARcr[i], MIC[i] ) << 10;
temp2 = B[i] << 1;
temp1 = sub( temp1, temp2);
temp1 = mult_r( INVA[i], temp1 );
LARrpp[i] = add( temp1, temp1 );
}
//
// for k_start=0 to k_end=12
//
// interpolation of LARrpp[1..8] to get LARrp[1..8]
for (i=1; i<=8; i++)
{
// for k_start=0 to k_end=12
LARrp[i] = add( (SHORT)(psi->OldLARrpp[i] >> 2), (SHORT)(LARrpp[i] >> 2) );
LARrp[i] = add( LARrp[i], (SHORT)(psi->OldLARrpp[i] >> 1) );
}
// computation of reflection coefficients rrp[1..8]
Comprp(psi, LARrp, rrp);
// short term synthesis filtering
Compsr(psi, wt, rrp, 0, 12, sr);
//
// for k_start=13 to k_end=26
//
// interpolation of LARrpp[1..8] to get LARrp[1..8]
for (i=1; i<=8; i++)
{
// for k_start=13 to k_end=26
LARrp[i] = add( (SHORT)(psi->OldLARrpp[i] >> 1), (SHORT)(LARrpp[i] >> 1) );
}
// computation of reflection coefficients rrp[1..8]
Comprp(psi, LARrp, rrp);
// short term synthesis filtering
Compsr(psi, wt, rrp, 13, 26, sr);
//
// for k_start=27 to k_end=39
//
// interpolation of LARrpp[1..8] to get LARrp[1..8]
for (i=1; i<=8; i++)
{
// for k_start=27 to k_end=39
LARrp[i] = add( (SHORT)(psi->OldLARrpp[i] >> 2), (SHORT)(LARrpp[i] >> 2) );
LARrp[i] = add( LARrp[i], (SHORT)(LARrpp[i] >> 1) );
}
// computation of reflection coefficients rrp[1..8]
Comprp(psi, LARrp, rrp);
// short term synthesis filtering
Compsr(psi, wt, rrp, 27, 39, sr);
//
// for k_start=40 to k_end=159
//
// interpolation of LARrpp[1..8] to get LARrp[1..8]
for (i=1; i<=8; i++)
{
// for k_start=40 to k_end=159
LARrp[i] = LARrpp[i];
}
// computation of reflection coefficients rrp[1..8]
Comprp(psi, LARrp, rrp);
// short term synthesis filtering
Compsr(psi, wt, rrp, 40, 159, sr);
//
// update oldLARrpp[1..8]
//
for (i=1; i<=8; i++)
{
psi->OldLARrpp[i] = LARrpp[i];
}
return;
}
//---------------------------------------------------------------------
//
// decodePostproc()
//
//---------------------------------------------------------------------
void decodePostproc(PSTREAMINSTANCE psi, _In_reads_(160) LPSHORT sr, _Out_writes_(160) LPSHORT srop)
{
UINT k;
// deemphasis filtering
for (k=0; k<=159; k++)
{
srop[k] = psi->msr = add(sr[k], mult_r(psi->msr, 28180));
// upscaling and truncation of the output signal
srop[k] = (add(srop[k], srop[k])) & 0xFFF8;
}
return;
}
//---------------------------------------------------------------------
//
// Compsr()
//
// The rrp parameter is annotated as 9 elements. However the algorithm
// uses only elements 1..8.
//
//---------------------------------------------------------------------
void Compsr(PSTREAMINSTANCE psi, _In_reads_(k_end-k_start+1) LPSHORT wt, _In_reads_(9) LPSHORT rrp, UINT k_start, UINT k_end, _Out_writes_(k_end-k_start+1) LPSHORT sr)
{
UINT i, k;
SHORT sri;
for (k=k_start; k<=k_end; k++)
{
sri = wt[k];
for (i=1; i<=8; i++)
{
sri = sub( sri, mult_r(rrp[9-i], psi->v[8-i]) );
psi->v[9-i] = add( psi->v[8-i], mult_r( rrp[9-i], sri ) );
}
sr[k] = sri;
psi->v[0] = sri;
}
return;
}
//=====================================================================
//=====================================================================
//
// Math and helper routines
//
//=====================================================================
//=====================================================================
//
// The 8-/16-bit PCM conversion routines are implemented as seperate
// functions to allow easy modification if we someday wish to do
// something more sophisticated that simple truncation... They are
// prototyped as inline so there should be no performance penalty.
//
//
SHORT Convert8To16BitPCM(BYTE bPCM8)
{
return( ((SHORT)bPCM8) - 0x80 ) << 8;
}
BYTE Convert16To8BitPCM(SHORT iPCM16)
{
return(BYTE)((iPCM16 >> 8) + 0x80);
}
SHORT add(SHORT var1, SHORT var2)
{
LONG sum;
sum = (LONG) var1 + (LONG) var2;
if (sum < -32768L) return -32768;
if (sum > 32767L) return 32767;
return(SHORT) sum;
}
SHORT sub(SHORT var1, SHORT var2)
{
LONG diff;
diff = (LONG) var1 - (LONG) var2;
if (diff < -32768L) return -32768;
if (diff > 32767L) return 32767;
return(SHORT) diff;
}
SHORT mult(SHORT var1, SHORT var2)
{
LONG product;
product = (LONG) var1 * (LONG) var2;
if (product >= 0x40000000) product=0x3FFFFFFF;
return( (SHORT) HIWORD((DWORD)(product<<1)) );
}
SHORT mult_r(SHORT var1, SHORT var2)
{
LONG product;
product = ((LONG) var1 * (LONG) var2) + 16384L;
if (product >= 0x40000000) product=0x3FFFFFFF;
return( (SHORT) HIWORD((DWORD)(product<<1)) );
}
SHORT gabs(SHORT var1)
{
if (var1 >= 0) return var1;
if (var1 == -32768) return 32767;
return -var1;
}
SHORT gdiv(SHORT num, SHORT denum)
{
UINT k;
LONG l_num, l_denum;
SHORT div;
l_num = num;
l_denum = denum;
div = 0;
for (k=0; k<15; k++)
{
div = div << 1;
l_num = l_num << 1;
if (l_num >= l_denum)
{
l_num = l_sub(l_num, l_denum);
div = add(div,1);
}
}
return div;
}
LONG l_mult(SHORT var1, SHORT var2)
{
LONG product;
product = (LONG) var1 * (LONG) var2;
return product << 1;
}
LONG l_add(LONG l_var1, LONG l_var2)
{
LONG l_sum;
// perform long addition
l_sum = l_var1 + l_var2;
// check for under or overflow
if (IsNeg(l_var1))
{
if (IsNeg(l_var2) && !IsNeg(l_sum))
{
return 0x80000000;
}
} else
{
if (!IsNeg(l_var2) && IsNeg(l_sum))
{
return 0x7FFFFFFF;
}
}
return l_sum;
}
LONG l_sub(LONG l_var1, LONG l_var2)
{
LONG l_diff;
// perform subtraction
l_diff = l_var1 - l_var2;
// check for underflow
if ( (l_var1<0) && (l_var2>0) && (l_diff>0) ) l_diff=0x80000000;
// check for overflow
if ( (l_var1>0) && (l_var2<0) && (l_diff<0) ) l_diff=0x7FFFFFFF;
return l_diff;
}
SHORT norm(LONG l_var)
{
UINT i;
i=0;
if (l_var > 0)
{
while (l_var < 1073741824)
{
i++;
l_var = l_var << 1;
}
} else if (l_var < 0)
{
while (l_var > -1073741824)
{
i++;
l_var = l_var << 1;
}
}
return(SHORT)i;
}
LONG IsNeg(LONG x)
{
return(x & 0x80000000);
}
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