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/*****************************************************************************
(C) copyright Fraunhofer IIS (2001)
All Rights Reserved
Please be advised that this software and/or program delivery is
Confidential Information of Fraunhofer and subject to and covered by the
Fraunhofer IIS Software Evaluation Agreement
between Google Inc. and Fraunhofer
effective and in full force since March 1, 2012.
You may use this software and/or program only under the terms and
conditions described in the above mentioned Fraunhofer IIS Software
Evaluation Agreement. Any other and/or further use requires a separate agreement.
$Id$
Description: FDKaacLdEnc_MdctTransform480:
The module FDKaacLdEnc_MdctTransform will perform the MDCT.
The MDCT supports the sine window and
the zero padded window. The algorithm of the MDCT
can be divided in Windowing, PreModulation, Fft and
PostModulation.
This software and/or program is protected by copyright law and international
treaties. Any reproduction or distribution of this software and/or program,
or any portion of it, may result in severe civil and criminal penalties, and
will be prosecuted to the maximum extent possible under law.
******************************************************************************/
#include "transform.h"
#include "dct.h"
#include "psy_const.h"
#include "aacEnc_rom.h"
#include "FDK_tools_rom.h"
INT FDKaacEnc_Transform_Real (const INT_PCM * pTimeData,
FIXP_DBL *RESTRICT mdctData,
const INT blockType,
const INT windowShape,
INT *prevWindowShape,
const INT frameLength,
INT *mdctData_e,
INT filterType
,FIXP_DBL * RESTRICT overlapAddBuffer
)
{
const INT_PCM * RESTRICT timeData;
INT i;
/* tl: transform length
fl: left window slope length
nl: left window slope offset
fr: right window slope length
nr: right window slope offset
See FDK_tools/doc/intern/mdct.tex for more detail. */
int tl, fl, nl, fr, nr;
const FIXP_WTP * RESTRICT pLeftWindowPart;
const FIXP_WTP * RESTRICT pRightWindowPart;
/*
* MDCT scale:
* + 1: fMultDiv2() in windowing.
* + 1: Because of factor 1/2 in Princen-Bradley compliant windowed TDAC.
*/
*mdctData_e = 1+1;
tl = frameLength;
timeData = pTimeData;
switch( blockType ) {
case LONG_WINDOW:
{
int offset = (windowShape == LOL_WINDOW) ? ((frameLength * 3)>>2) : 0;
fl = frameLength - offset;
fr = frameLength - offset;
}
break;
case STOP_WINDOW:
fl = frameLength >> 3;
fr = frameLength;
break;
case START_WINDOW: /* or StopStartSequence */
fl = frameLength;
fr = frameLength >> 3;
break;
case SHORT_WINDOW:
fl = fr = frameLength >> 3;
tl >>= 3;
timeData = pTimeData + 3*fl + (fl/2);
break;
default:
FDK_ASSERT(0);
return -1;
break;
}
/* Taken from FDK_tools/src/mdct.cpp Derive NR and NL */
nr = (tl - fr)>>1;
nl = (tl - fl)>>1;
pLeftWindowPart = FDKgetWindowSlope(fl, *prevWindowShape);
pRightWindowPart = FDKgetWindowSlope(fr, windowShape);
/* windowing */
if (filterType != FB_ELD)
{
/* Left window slope offset */
for (i=0; i<nl ; i++)
{
#if SAMPLE_BITS == DFRACT_BITS /* SPC_BITS and DFRACT_BITS should be equal. */
mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] >> ( 1 );
#else
mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] << (DFRACT_BITS - SAMPLE_BITS - 1);
#endif
}
/* Left window slope */
for (i=0; i<fl/2; i++)
{
FIXP_DBL tmp0;
tmp0 = fMultDiv2((FIXP_PCM)timeData[i+nl], pLeftWindowPart[i].v.im);
mdctData[(tl/2)+i+nl] = fMultSubDiv2(tmp0, (FIXP_PCM)timeData[tl-nl-i-1], pLeftWindowPart[i].v.re);
}
/* Right window slope offset */
for(i=0; i<nr; i++)
{
#if SAMPLE_BITS == DFRACT_BITS /* This should be SPC_BITS instead of DFRACT_BITS. */
mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] >> (1);
#else
mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] << (DFRACT_BITS - SAMPLE_BITS - 1);
#endif
}
/* Right window slope */
for (i=0; i<fr/2; i++)
{
FIXP_DBL tmp1;
tmp1 = fMultDiv2((FIXP_PCM)timeData[tl+nr+i], pRightWindowPart[i].v.re);
mdctData[(tl/2)-nr-i-1] = -fMultAddDiv2(tmp1, (FIXP_PCM)timeData[(tl*2)-nr-i-1], pRightWindowPart[i].v.im);
}
}
if (filterType == FB_ELD)
{
const FIXP_WTB *pWindowELD=NULL;
int i, N = frameLength, L = frameLength;
if (frameLength == 512) {
pWindowELD = ELDAnalysis512;
} else {
pWindowELD = ELDAnalysis480;
}
for(i=0;i<N/4;i++)
{
FIXP_DBL z0, outval;
z0 = (fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i])<< (WTS0-1)) + (fMult((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N/2+i])<< (WTS0-1));
outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1));
outval += (fMultDiv2((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N+N/2+i]) >> (-WTS1) );
outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i])>> (-WTS2-1));
overlapAddBuffer[N/2+i] = overlapAddBuffer[i];
overlapAddBuffer[i] = z0;
mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1));
mdctData[N-1-i] = outval;
overlapAddBuffer[N+N/2-1-i] = outval;
}
for(i=N/4;i<N/2;i++)
{
FIXP_DBL z0, outval;
z0 = fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i]) << (WTS0-1);
outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1)) ;
outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i]) >> (-WTS2-1));
overlapAddBuffer[N/2+i] = overlapAddBuffer[i] + (fMult((FIXP_PCM)timeData[L-N/4+i], pWindowELD[N/2+i])<< (WTS0-1) );
overlapAddBuffer[i] = z0;
mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1));
mdctData[N-1-i] = outval;
overlapAddBuffer[N+N/2-1-i] = outval;
}
}
dct_IV(mdctData, tl, mdctData_e);
*prevWindowShape = windowShape;
return 0;
}
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