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+/***************************** MPEG-4 AAC Encoder **************************
+
+ (C) Copyright Fraunhofer IIS (1999)
+ 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.
+
+
+ $Id$
+ Initial author: M. Werner
+ contents/description: Band/Line energy calculations
+
+ 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 "band_nrg.h"
+
+
+/*****************************************************************************
+ functionname: FDKaacEnc_CalcSfbMaxScaleSpec
+ description:
+ input:
+ output:
+*****************************************************************************/
+void
+FDKaacEnc_CalcSfbMaxScaleSpec(const FIXP_DBL *RESTRICT mdctSpectrum,
+ const INT *RESTRICT bandOffset,
+ INT *RESTRICT sfbMaxScaleSpec,
+ const INT numBands)
+{
+ INT i,j;
+ FIXP_DBL maxSpc, tmp;
+
+ for(i=0; i<numBands; i++) {
+ maxSpc = (FIXP_DBL)0;
+ for (j=bandOffset[i]; j<bandOffset[i+1]; j++) {
+ tmp = fixp_abs(mdctSpectrum[j]);
+ maxSpc = fixMax(maxSpc, tmp);
+ }
+ sfbMaxScaleSpec[i] = (maxSpc==(FIXP_DBL)0) ? (DFRACT_BITS-2) : CntLeadingZeros(maxSpc)-1;
+ /* CountLeadingBits() is not necessary here since test value is always > 0 */
+ }
+}
+
+/*****************************************************************************
+ functionname: FDKaacEnc_CheckBandEnergyOptim
+ description:
+ input:
+ output:
+*****************************************************************************/
+FIXP_DBL
+FDKaacEnc_CheckBandEnergyOptim(const FIXP_DBL *RESTRICT mdctSpectrum,
+ INT *RESTRICT sfbMaxScaleSpec,
+ const INT *RESTRICT bandOffset,
+ const INT numBands,
+ FIXP_DBL *RESTRICT bandEnergy,
+ FIXP_DBL *RESTRICT bandEnergyLdData,
+ INT minSpecShift)
+{
+ INT i, j, scale, nr = 0;
+ FIXP_DBL maxNrgLd = FL2FXCONST_DBL(-1.0f);
+ FIXP_DBL maxNrg = 0;
+ FIXP_DBL spec;
+
+ for(i=0; i<numBands; i++) {
+ scale = fixMax(0, sfbMaxScaleSpec[i]-4);
+ FIXP_DBL tmp = 0;
+ for (j=bandOffset[i]; j<bandOffset[i+1]; j++){
+ spec = mdctSpectrum[j]<<scale;
+ tmp = fPow2AddDiv2(tmp, spec);
+ }
+ bandEnergy[i] = tmp<<1;
+
+ /* calculate ld of bandNrg, subtract scaling */
+ bandEnergyLdData[i] = CalcLdData(bandEnergy[i]);
+ if (bandEnergyLdData[i] != FL2FXCONST_DBL(-1.0f)) {
+ bandEnergyLdData[i] -= scale*FL2FXCONST_DBL(2.0/64);
+ }
+ /* find index of maxNrg */
+ if (bandEnergyLdData[i] > maxNrgLd) {
+ maxNrgLd = bandEnergyLdData[i];
+ nr = i;
+ }
+ }
+
+ /* return unscaled maxNrg*/
+ scale = fixMax(0,sfbMaxScaleSpec[nr]-4);
+ scale = fixMax(2*(minSpecShift-scale),-(DFRACT_BITS-1));
+
+ maxNrg = scaleValue(bandEnergy[nr], scale);
+
+ return maxNrg;
+}
+
+/*****************************************************************************
+ functionname: FDKaacEnc_CalcBandEnergyOptimLong
+ description:
+ input:
+ output:
+*****************************************************************************/
+INT
+FDKaacEnc_CalcBandEnergyOptimLong(const FIXP_DBL *RESTRICT mdctSpectrum,
+ INT *RESTRICT sfbMaxScaleSpec,
+ const INT *RESTRICT bandOffset,
+ const INT numBands,
+ FIXP_DBL *RESTRICT bandEnergy,
+ FIXP_DBL *RESTRICT bandEnergyLdData)
+{
+ INT i, j, shiftBits = 0;
+ FIXP_DBL maxNrgLd = FL2FXCONST_DBL(0.0f);
+
+ FIXP_DBL spec;
+
+ for(i=0; i<numBands; i++) {
+ INT leadingBits = sfbMaxScaleSpec[i]-4; /* max sfbWidth = 96 ; 2^7=128 => 7/2 = 4 (spc*spc) */
+ FIXP_DBL tmp = FL2FXCONST_DBL(0.0);
+ /* don't use scaleValue() here, it increases workload quite sufficiently... */
+ if (leadingBits>=0) {
+ for (j=bandOffset[i];j<bandOffset[i+1];j++) {
+ spec = mdctSpectrum[j]<<leadingBits;
+ tmp = fPow2AddDiv2(tmp, spec);
+ }
+ } else {
+ INT shift = -leadingBits;
+ for (j=bandOffset[i];j<bandOffset[i+1];j++){
+ spec = mdctSpectrum[j]>>shift;
+ tmp = fPow2AddDiv2(tmp, spec);
+ }
+ }
+ bandEnergy[i] = tmp<<1;
+ }
+
+ /* calculate ld of bandNrg, subtract scaling */
+ LdDataVector(bandEnergy, bandEnergyLdData, numBands);
+ for(i=numBands; i--!=0; ) {
+ FIXP_DBL scaleDiff = (sfbMaxScaleSpec[i]-4)*FL2FXCONST_DBL(2.0/64);
+
+ bandEnergyLdData[i] = (bandEnergyLdData[i] >= ((FL2FXCONST_DBL(-1.f)>>1) + (scaleDiff>>1)))
+ ? bandEnergyLdData[i]-scaleDiff : FL2FXCONST_DBL(-1.f);
+ /* find maxNrgLd */
+ maxNrgLd = fixMax(maxNrgLd, bandEnergyLdData[i]);
+ }
+
+ if (maxNrgLd<=(FIXP_DBL)0)
+ {
+ for(i=numBands; i--!=0; )
+ {
+ INT scale = fixMin((sfbMaxScaleSpec[i]-4)<<1,(DFRACT_BITS-1));
+ bandEnergy[i] = scaleValue(bandEnergy[i], -scale);
+ }
+ return 0;
+ }
+ else
+ { /* scale down NRGs */
+ while (maxNrgLd>FL2FXCONST_DBL(0.0f))
+ {
+ maxNrgLd -= FL2FXCONST_DBL(2.0/64);
+ shiftBits++;
+ }
+ for(i=numBands; i--!=0; )
+ {
+ INT scale = fixMin( ((sfbMaxScaleSpec[i]-4)+shiftBits)<<1, (DFRACT_BITS-1));
+ bandEnergyLdData[i] -= shiftBits*FL2FXCONST_DBL(2.0/64);
+ bandEnergy[i] = scaleValue(bandEnergy[i], -scale);
+ }
+ return shiftBits;
+ }
+}
+
+
+/*****************************************************************************
+ functionname: FDKaacEnc_CalcBandEnergyOptimShort
+ description:
+ input:
+ output:
+*****************************************************************************/
+void
+FDKaacEnc_CalcBandEnergyOptimShort(const FIXP_DBL *RESTRICT mdctSpectrum,
+ INT *RESTRICT sfbMaxScaleSpec,
+ const INT *RESTRICT bandOffset,
+ const INT numBands,
+ FIXP_DBL *RESTRICT bandEnergy)
+{
+ INT i, j;
+
+ for(i=0; i<numBands; i++)
+ {
+ int leadingBits = fixMax(0,sfbMaxScaleSpec[i]-4); /* max sfbWidth = 96 ; 2^7=128 => 7/2 = 4 (spc*spc) */
+ FIXP_DBL tmp = FL2FXCONST_DBL(0.0);
+ for (j=bandOffset[i];j<bandOffset[i+1];j++)
+ {
+ FIXP_DBL spec = mdctSpectrum[j]<<leadingBits;
+ tmp = fPow2AddDiv2(tmp, spec);
+ }
+ bandEnergy[i] = tmp<<1;
+ }
+
+ for(i=0; i<numBands; i++)
+ {
+ INT scale = 2*fixMax(0,sfbMaxScaleSpec[i]-4); /* max sfbWidth = 96 ; 2^7=128 => 7/2 = 4 (spc*spc) */
+ scale = fixMin(scale,(DFRACT_BITS-1));
+ bandEnergy[i] >>= scale;
+ }
+}
+
+
+/*****************************************************************************
+ functionname: FDKaacEnc_CalcBandNrgMSOpt
+ description:
+ input:
+ output:
+*****************************************************************************/
+void FDKaacEnc_CalcBandNrgMSOpt(const FIXP_DBL *RESTRICT mdctSpectrumLeft,
+ const FIXP_DBL *RESTRICT mdctSpectrumRight,
+ INT *RESTRICT sfbMaxScaleSpecLeft,
+ INT *RESTRICT sfbMaxScaleSpecRight,
+ const INT *RESTRICT bandOffset,
+ const INT numBands,
+ FIXP_DBL *RESTRICT bandEnergyMid,
+ FIXP_DBL *RESTRICT bandEnergySide,
+ INT calcLdData,
+ FIXP_DBL *RESTRICT bandEnergyMidLdData,
+ FIXP_DBL *RESTRICT bandEnergySideLdData)
+{
+ INT i, j, minScale;
+ FIXP_DBL NrgMid, NrgSide, specm, specs;
+
+ for (i=0; i<numBands; i++) {
+
+ NrgMid = NrgSide = FL2FXCONST_DBL(0.0);
+ minScale = fixMin(sfbMaxScaleSpecLeft[i], sfbMaxScaleSpecRight[i])-4;
+ minScale = fixMax(0, minScale);
+
+ if (minScale > 0) {
+ for (j=bandOffset[i];j<bandOffset[i+1];j++) {
+ FIXP_DBL specL = mdctSpectrumLeft[j]<<(minScale-1);
+ FIXP_DBL specR = mdctSpectrumRight[j]<<(minScale-1);
+ specm = specL + specR;
+ specs = specL - specR;
+ NrgMid = fPow2AddDiv2(NrgMid, specm);
+ NrgSide = fPow2AddDiv2(NrgSide, specs);
+ }
+ } else {
+ for (j=bandOffset[i];j<bandOffset[i+1];j++) {
+ FIXP_DBL specL = mdctSpectrumLeft[j]>>1;
+ FIXP_DBL specR = mdctSpectrumRight[j]>>1;
+ specm = specL + specR;
+ specs = specL - specR;
+ NrgMid = fPow2AddDiv2(NrgMid, specm);
+ NrgSide = fPow2AddDiv2(NrgSide, specs);
+ }
+ }
+ bandEnergyMid[i] = NrgMid<<1;
+ bandEnergySide[i] = NrgSide<<1;
+ }
+
+ if(calcLdData) {
+ LdDataVector(bandEnergyMid, bandEnergyMidLdData, numBands);
+ LdDataVector(bandEnergySide, bandEnergySideLdData, numBands);
+ }
+
+ for (i=0; i<numBands; i++)
+ {
+ INT minScale = fixMin(sfbMaxScaleSpecLeft[i], sfbMaxScaleSpecRight[i]);
+ INT scale = fixMax(0, 2*(minScale-4));
+
+ if (calcLdData)
+ {
+ /* using the minimal scaling of left and right channel can cause very small energies;
+ check ldNrg before subtract scaling multiplication: fract*INT we don't need fMult */
+
+ int minus = scale*FL2FXCONST_DBL(1.0/64);
+
+ if (bandEnergyMidLdData[i] != FL2FXCONST_DBL(-1.0f))
+ bandEnergyMidLdData[i] -= minus;
+
+ if (bandEnergySideLdData[i] != FL2FXCONST_DBL(-1.0f))
+ bandEnergySideLdData[i] -= minus;
+ }
+ scale = fixMin(scale, (DFRACT_BITS-1));
+ bandEnergyMid[i] >>= scale;
+ bandEnergySide[i] >>= scale;
+ }
+}