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fdk-aac/libAACenc/src/intensity.cpp

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Snapshot 2bda038c163298531d47394bc2c09e1409c5d0db Change-Id: If584e579464f28b97d50e51fc76ba654a5536c54
2012-07-11 19:15:24 +02:00
/* -----------------------------------------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android
Disclaimer update, lib version increment - Update disclaimer in all source files. - Increment library version in each FDK sub-module. Bug 9428126 Change-Id: I490b96d4ee472246b01483202b0bb4f1e9c2a5d7
2013-08-09 02:26:40 +02:00
<EFBFBD> Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur F<EFBFBD>rderung der angewandten Forschung e.V.
Snapshot 2bda038c163298531d47394bc2c09e1409c5d0db Change-Id: If584e579464f28b97d50e51fc76ba654a5536c54
2012-07-11 19:15:24 +02:00
All rights reserved.
1. INTRODUCTION
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
of the MPEG specifications.
Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
individually for the purpose of encoding or decoding bit streams in products that are compliant with
the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
software may already be covered under those patent licenses when it is used for those licensed purposes only.
Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
applications information and documentation.
2. COPYRIGHT LICENSE
Redistribution and use in source and binary forms, with or without modification, are permitted without
payment of copyright license fees provided that you satisfy the following conditions:
You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
your modifications thereto in source code form.
You must retain the complete text of this software license in the documentation and/or other materials
provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
modifications thereto to recipients of copies in binary form.
The name of Fraunhofer may not be used to endorse or promote products derived from this library without
prior written permission.
You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
software or your modifications thereto.
Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
and the date of any change. For modified versions of the FDK AAC Codec, the term
"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
3. NO PATENT LICENSE
NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
respect to this software.
You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
by appropriate patent licenses.
4. DISCLAIMER
This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
or business interruption, however caused and on any theory of liability, whether in contract, strict
liability, or tort (including negligence), arising in any way out of the use of this software, even if
advised of the possibility of such damage.
5. CONTACT INFORMATION
Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany
www.iis.fraunhofer.de/amm
amm-info@iis.fraunhofer.de
----------------------------------------------------------------------------------------------------------- */
/******************************** MPEG Audio Encoder **************************
Initial author: A. Horndasch (code originally from lwr) / Josef Hoepfl (FDK)
contents/description: intensity stereo processing
******************************************************************************/
#include "intensity.h"
#include "interface.h"
#include "psy_configuration.h"
#include "psy_const.h"
#include "qc_main.h"
#include "bit_cnt.h"
/* only set an IS seed it left/right channel correlation is above IS_CORR_THRESH */
#define IS_CORR_THRESH FL2FXCONST_DBL(0.95f)
/* when expanding the IS region to more SFBs only accept an error that is
* not more than IS_TOTAL_ERROR_THRESH overall and
* not more than IS_LOCAL_ERROR_THRESH for the current SFB */
#define IS_TOTAL_ERROR_THRESH FL2FXCONST_DBL(0.04f)
#define IS_LOCAL_ERROR_THRESH FL2FXCONST_DBL(0.01f)
/* the maximum allowed change of the intensity direction (unit: IS scale) - scaled with factor 0.25 - */
#define IS_DIRECTION_DEVIATION_THRESH_SF 2
#define IS_DIRECTION_DEVIATION_THRESH FL2FXCONST_DBL(2.0f/(1<<IS_DIRECTION_DEVIATION_THRESH_SF))
/* IS regions need to have a minimal percentage of the overall loudness, e.g. 0.06 == 6% */
#define IS_REGION_MIN_LOUDNESS FL2FXCONST_DBL(0.1f)
/* only perform IS if IS_MIN_SFBS neighboring SFBs can be processed */
#define IS_MIN_SFBS 6
/* only do IS if
* if IS_LEFT_RIGHT_RATIO_THRESH < sfbEnergyLeft[sfb]/sfbEnergyRight[sfb] < 1 / IS_LEFT_RIGHT_RATIO_THRESH
* -> no IS if the panning angle is not far from the middle, MS will do */
/* this is equivalent to a scale of +/-1.02914634566 */
#define IS_LEFT_RIGHT_RATIO_THRESH FL2FXCONST_DBL(0.7f)
/* scalefactor of realScale */
#define REAL_SCALE_SF 1
/* scalefactor overallLoudness */
#define OVERALL_LOUDNESS_SF 6
/* scalefactor for sum over max samples per goup */
#define MAX_SFB_PER_GROUP_SF 6
/* scalefactor for sum of mdct spectrum */
#define MDCT_SPEC_SF 6
typedef struct
{
FIXP_DBL corr_thresh; /*!< Only set an IS seed it left/right channel correlation is above corr_thresh */
FIXP_DBL total_error_thresh; /*!< When expanding the IS region to more SFBs only accept an error that is
not more than 'total_error_thresh' overall. */
FIXP_DBL local_error_thresh; /*!< When expanding the IS region to more SFBs only accept an error that is
not more than 'local_error_thresh' for the current SFB. */
FIXP_DBL direction_deviation_thresh; /*!< The maximum allowed change of the intensity direction (unit: IS scale) */
FIXP_DBL is_region_min_loudness; /*!< IS regions need to have a minimal percentage of the overall loudness, e.g. 0.06 == 6% */
INT min_is_sfbs; /*!< Only perform IS if 'min_is_sfbs' neighboring SFBs can be processed */
FIXP_DBL left_right_ratio_threshold; /*!< No IS if the panning angle is not far from the middle, MS will do */
} INTENSITY_PARAMETERS;
/*****************************************************************************
functionname: calcSfbMaxScale
description: Calc max value in scalefactor band
input: *mdctSpectrum
l1
l2
output: none
returns: scalefactor
*****************************************************************************/
static INT
calcSfbMaxScale(const FIXP_DBL *mdctSpectrum,
const INT l1,
const INT l2)
{
INT i;
INT sfbMaxScale;
FIXP_DBL maxSpc;
maxSpc = FL2FXCONST_DBL(0.0);
for (i=l1; i<l2; i++) {
FIXP_DBL tmp = fixp_abs((FIXP_DBL)mdctSpectrum[i]);
maxSpc = fixMax(maxSpc, tmp);
}
sfbMaxScale = (maxSpc==FL2FXCONST_DBL(0.0)) ? (DFRACT_BITS-2) : CntLeadingZeros(maxSpc)-1;
return sfbMaxScale;
}
/*****************************************************************************
functionname: FDKaacEnc_initIsParams
description: Initialization of intensity parameters
input: isParams
output: isParams
returns: none
*****************************************************************************/
static void
FDKaacEnc_initIsParams(INTENSITY_PARAMETERS *isParams)
{
isParams->corr_thresh = IS_CORR_THRESH;
isParams->total_error_thresh = IS_TOTAL_ERROR_THRESH;
isParams->local_error_thresh = IS_LOCAL_ERROR_THRESH;
isParams->direction_deviation_thresh = IS_DIRECTION_DEVIATION_THRESH;
isParams->is_region_min_loudness = IS_REGION_MIN_LOUDNESS;
isParams->min_is_sfbs = IS_MIN_SFBS;
isParams->left_right_ratio_threshold = IS_LEFT_RIGHT_RATIO_THRESH;
}
/*****************************************************************************
functionname: FDKaacEnc_prepareIntensityDecision
description: Prepares intensity decision
input: sfbEnergyLeft
sfbEnergyRight
sfbEnergyLdDataLeft
sfbEnergyLdDataRight
mdctSpectrumLeft
sfbEnergyLdDataRight
isParams
output: hrrErr scale: none
isMask scale: none
realScale scale: LD_DATA_SHIFT + REAL_SCALE_SF
normSfbLoudness scale: none
returns: none
*****************************************************************************/
static void
FDKaacEnc_prepareIntensityDecision(const FIXP_DBL *sfbEnergyLeft,
const FIXP_DBL *sfbEnergyRight,
const FIXP_DBL *sfbEnergyLdDataLeft,
const FIXP_DBL *sfbEnergyLdDataRight,
const FIXP_DBL *mdctSpectrumLeft,
const FIXP_DBL *mdctSpectrumRight,
const INTENSITY_PARAMETERS *isParams,
FIXP_DBL *hrrErr,
INT *isMask,
FIXP_DBL *realScale,
FIXP_DBL *normSfbLoudness,
const INT sfbCnt,
const INT sfbPerGroup,
const INT maxSfbPerGroup,
const INT *sfbOffset)
{
INT j,sfb,sfboffs;
INT grpCounter;
/* temporary variables to compute loudness */
FIXP_DBL overallLoudness[MAX_NO_OF_GROUPS];
/* temporary variables to compute correlation */
FIXP_DBL channelCorr[MAX_GROUPED_SFB];
FIXP_DBL ml, mr;
FIXP_DBL prod_lr;
FIXP_DBL square_l, square_r;
FIXP_DBL tmp_l, tmp_r;
FIXP_DBL inv_n;
FDKmemclear(channelCorr, MAX_GROUPED_SFB*sizeof(FIXP_DBL));
FDKmemclear(normSfbLoudness, MAX_GROUPED_SFB*sizeof(FIXP_DBL));
FDKmemclear(overallLoudness, MAX_NO_OF_GROUPS*sizeof(FIXP_DBL));
FDKmemclear(realScale, MAX_GROUPED_SFB*sizeof(FIXP_DBL));
for (grpCounter = 0, sfboffs = 0; sfboffs < sfbCnt; sfboffs += sfbPerGroup, grpCounter++) {
overallLoudness[grpCounter] = FL2FXCONST_DBL(0.0f);
for (sfb = 0; sfb < maxSfbPerGroup; sfb++) {
INT sL,sR,s;
FIXP_DBL isValue = sfbEnergyLdDataLeft[sfb+sfboffs]-sfbEnergyLdDataRight[sfb+sfboffs];
/* delimitate intensity scale value to representable range */
realScale[sfb + sfboffs] = fixMin(FL2FXCONST_DBL(60.f/(1<<(REAL_SCALE_SF+LD_DATA_SHIFT))), fixMax(FL2FXCONST_DBL(-60.f/(1<<(REAL_SCALE_SF+LD_DATA_SHIFT))), isValue));
sL = fixMax(0,(CntLeadingZeros(sfbEnergyLeft[sfb + sfboffs])-1));
sR = fixMax(0,(CntLeadingZeros(sfbEnergyRight[sfb + sfboffs])-1));
s = (fixMin(sL,sR)>>2)<<2;
normSfbLoudness[sfb + sfboffs] = sqrtFixp(sqrtFixp(((sfbEnergyLeft[sfb + sfboffs]<<s) >> 1) + ((sfbEnergyRight[sfb + sfboffs]<<s) >> 1))) >> (s>>2);
overallLoudness[grpCounter] += normSfbLoudness[sfb + sfboffs] >> OVERALL_LOUDNESS_SF;
/* don't do intensity if
* - panning angle is too close to the middle or
* - one channel is non-existent or
* - if it is dual mono */
if( (sfbEnergyLeft[sfb + sfboffs] >= fMult(isParams->left_right_ratio_threshold,sfbEnergyRight[sfb + sfboffs]))
&& (fMult(isParams->left_right_ratio_threshold,sfbEnergyLeft[sfb + sfboffs]) <= sfbEnergyRight[sfb + sfboffs]) ) {
/* this will prevent post processing from considering this SFB for merging */
hrrErr[sfb + sfboffs] = FL2FXCONST_DBL(1.0/8.0);
}
}
}
for (grpCounter = 0, sfboffs = 0; sfboffs < sfbCnt; sfboffs += sfbPerGroup, grpCounter++) {
INT invOverallLoudnessSF;
FIXP_DBL invOverallLoudness;
if (overallLoudness[grpCounter] == FL2FXCONST_DBL(0.0)) {
invOverallLoudness = FL2FXCONST_DBL(0.0);
invOverallLoudnessSF = 0;
}
else {
invOverallLoudness = fDivNorm((FIXP_DBL)MAXVAL_DBL, overallLoudness[grpCounter],&invOverallLoudnessSF);
invOverallLoudnessSF = invOverallLoudnessSF - OVERALL_LOUDNESS_SF + 1; /* +1: compensate fMultDiv2() in subsequent loop */
}
invOverallLoudnessSF = fixMin(fixMax(invOverallLoudnessSF,-(DFRACT_BITS-1)),DFRACT_BITS-1);
for (sfb = 0; sfb < maxSfbPerGroup; sfb++) {
FIXP_DBL tmp;
tmp = fMultDiv2((normSfbLoudness[sfb + sfboffs]>>OVERALL_LOUDNESS_SF)<<OVERALL_LOUDNESS_SF,invOverallLoudness);
normSfbLoudness[sfb + sfboffs] = scaleValue(tmp, invOverallLoudnessSF);
channelCorr[sfb + sfboffs] = FL2FXCONST_DBL(0.0f);
FDK_ASSERT(50 >= 49);
/* max width of scalefactorband is 96; width's are always even */
/* inv_n is scaled with factor 2 to compensate fMultDiv2() in subsequent loops */
inv_n = GetInvInt((sfbOffset[sfb + sfboffs + 1] - sfbOffset[sfb + sfboffs])>>1);
if (inv_n > FL2FXCONST_DBL(0.0f)) {
INT s,sL,sR;
/* correlation := Pearson's product-moment coefficient */
/* compute correlation between channels and check if it is over threshold */
ml = FL2FXCONST_DBL(0.0f);
mr = FL2FXCONST_DBL(0.0f);
prod_lr = FL2FXCONST_DBL(0.0f);
square_l = FL2FXCONST_DBL(0.0f);
square_r = FL2FXCONST_DBL(0.0f);
sL = calcSfbMaxScale(mdctSpectrumLeft,sfbOffset[sfb+sfboffs],sfbOffset[sfb+sfboffs+1]);
sR = calcSfbMaxScale(mdctSpectrumRight,sfbOffset[sfb+sfboffs],sfbOffset[sfb+sfboffs+1]);
s = fixMin(sL,sR);
for (j = sfbOffset[sfb + sfboffs]; j < sfbOffset[sfb + sfboffs + 1]; j++) {
ml += fMultDiv2((mdctSpectrumLeft[j] << s),inv_n); // scaled with mdctScale - s + inv_n
mr += fMultDiv2((mdctSpectrumRight[j] << s),inv_n); // scaled with mdctScale - s + inv_n
}
ml = fMultDiv2(ml,inv_n); // scaled with mdctScale - s + inv_n
mr = fMultDiv2(mr,inv_n); // scaled with mdctScale - s + inv_n
for (j = sfbOffset[sfb + sfboffs]; j < sfbOffset[sfb + sfboffs + 1]; j++) {
tmp_l = fMultDiv2((mdctSpectrumLeft[j] << s),inv_n) - ml; // scaled with mdctScale - s + inv_n
tmp_r = fMultDiv2((mdctSpectrumRight[j] << s),inv_n) - mr; // scaled with mdctScale - s + inv_n
prod_lr += fMultDiv2(tmp_l,tmp_r); // scaled with 2*(mdctScale - s + inv_n) + 1
square_l += fPow2Div2(tmp_l); // scaled with 2*(mdctScale - s + inv_n) + 1
square_r += fPow2Div2(tmp_r); // scaled with 2*(mdctScale - s + inv_n) + 1
}
prod_lr = prod_lr << 1; // scaled with 2*(mdctScale - s + inv_n)
square_l = square_l << 1; // scaled with 2*(mdctScale - s + inv_n)
square_r = square_r << 1; // scaled with 2*(mdctScale - s + inv_n)
if (square_l > FL2FXCONST_DBL(0.0f) && square_r > FL2FXCONST_DBL(0.0f)) {
INT channelCorrSF = 0;
/* local scaling of square_l and square_r is compensated after sqrt calculation */
sL = fixMax(0,(CntLeadingZeros(square_l)-1));
sR = fixMax(0,(CntLeadingZeros(square_r)-1));
s = ((sL + sR)>>1)<<1;
sL = fixMin(sL,s);
sR = s-sL;
tmp = fMult(square_l<<sL,square_r<<sR);
tmp = sqrtFixp(tmp);
FDK_ASSERT(tmp > FL2FXCONST_DBL(0.0f));
/* numerator and denominator have the same scaling */
if (prod_lr < FL2FXCONST_DBL(0.0f) ) {
channelCorr[sfb + sfboffs] = -(fDivNorm(-prod_lr,tmp,&channelCorrSF));
}
else {
channelCorr[sfb + sfboffs] = (fDivNorm( prod_lr,tmp,&channelCorrSF));
}
channelCorrSF = fixMin(fixMax(( channelCorrSF + ((sL+sR)>>1)),-(DFRACT_BITS-1)),DFRACT_BITS-1);
if (channelCorrSF < 0) {
channelCorr[sfb + sfboffs] = channelCorr[sfb + sfboffs] >> (-channelCorrSF);
}
else {
/* avoid overflows due to limited computational accuracy */
if ( fAbs(channelCorr[sfb + sfboffs]) > (((FIXP_DBL)MAXVAL_DBL)>>channelCorrSF) ) {
if (channelCorr[sfb + sfboffs] < FL2FXCONST_DBL(0.0f))
channelCorr[sfb + sfboffs] = -(FIXP_DBL) MAXVAL_DBL;
else
channelCorr[sfb + sfboffs] = (FIXP_DBL) MAXVAL_DBL;
}
else {
channelCorr[sfb + sfboffs] = channelCorr[sfb + sfboffs] << channelCorrSF;
}
}
}
}
/* for post processing: hrrErr is the error in terms of (too little) correlation
* weighted with the loudness of the SFB; SFBs with small hrrErr can be merged */
if (hrrErr[sfb + sfboffs] == FL2FXCONST_DBL(1.0/8.0)) {
continue;
}
hrrErr[sfb + sfboffs] = fMultDiv2((FL2FXCONST_DBL(0.25f)-(channelCorr[sfb + sfboffs]>>2)),normSfbLoudness[sfb + sfboffs]);
/* set IS mask/vector to 1, if correlation is high enough */
if (fAbs(channelCorr[sfb + sfboffs]) >= isParams->corr_thresh) {
isMask[sfb + sfboffs] = 1;
}
}
}
}
/*****************************************************************************
functionname: FDKaacEnc_finalizeIntensityDecision
description: Finalizes intensity decision
input: isParams scale: none
hrrErr scale: none
realIsScale scale: LD_DATA_SHIFT + REAL_SCALE_SF
normSfbLoudness scale: none
output: isMask scale: none
returns: none
*****************************************************************************/
static void
FDKaacEnc_finalizeIntensityDecision(const FIXP_DBL *hrrErr,
INT *isMask,
const FIXP_DBL *realIsScale,
const FIXP_DBL *normSfbLoudness,
const INTENSITY_PARAMETERS *isParams,
const INT sfbCnt,
const INT sfbPerGroup,
const INT maxSfbPerGroup)
{
INT sfb,sfboffs, j;
INT startIsSfb = 0;
INT inIsBlock;
INT currentIsSfbCount;
FIXP_DBL overallHrrError;
FIXP_DBL isScaleLast = FL2FXCONST_DBL(0.0f);
FIXP_DBL isRegionLoudness;
for (sfboffs = 0; sfboffs < sfbCnt; sfboffs += sfbPerGroup) {
inIsBlock = 0;
currentIsSfbCount = 0;
overallHrrError = FL2FXCONST_DBL(0.0f);
isRegionLoudness = FL2FXCONST_DBL(0.0f);
for (sfb = 0; sfb < maxSfbPerGroup; sfb++) {
if (isMask[sfboffs + sfb] == 1) {
if (currentIsSfbCount == 0) {
startIsSfb = sfboffs + sfb;
isScaleLast = realIsScale[sfboffs + sfb];
}
inIsBlock = 1;
currentIsSfbCount++;
overallHrrError += hrrErr[sfboffs + sfb] >> (MAX_SFB_PER_GROUP_SF-3);
isRegionLoudness += normSfbLoudness[sfboffs + sfb] >> MAX_SFB_PER_GROUP_SF;
}
else {
/* based on correlation, IS should not be used
* -> use it anyway, if overall error is below threshold
* and if local error does not exceed threshold
* otherwise: check if there are enough IS SFBs
*/
if (inIsBlock) {
overallHrrError += hrrErr[sfboffs + sfb] >> (MAX_SFB_PER_GROUP_SF-3);
isRegionLoudness += normSfbLoudness[sfboffs + sfb] >> MAX_SFB_PER_GROUP_SF;
if ( (hrrErr[sfboffs + sfb] < (isParams->local_error_thresh>>3)) && (overallHrrError < (isParams->total_error_thresh>>MAX_SFB_PER_GROUP_SF)) ) {
currentIsSfbCount++;
/* overwrite correlation based decision */
isMask[sfboffs + sfb] = 1;
} else {
inIsBlock = 0;
}
}
}
/* check for large direction deviation */
if (inIsBlock) {
if( fAbs(isScaleLast-realIsScale[sfboffs + sfb]) < (isParams->direction_deviation_thresh>>(REAL_SCALE_SF+LD_DATA_SHIFT-IS_DIRECTION_DEVIATION_THRESH_SF)) ) {
isScaleLast = realIsScale[sfboffs + sfb];
}
else{
isMask[sfboffs + sfb] = 0;
inIsBlock = 0;
currentIsSfbCount--;
}
}
if (currentIsSfbCount > 0 && (!inIsBlock || sfb == maxSfbPerGroup - 1)) {
/* not enough SFBs -> do not use IS */
if (currentIsSfbCount < isParams->min_is_sfbs || (isRegionLoudness < isParams->is_region_min_loudness>>MAX_SFB_PER_GROUP_SF)) {
for(j = startIsSfb; j <= sfboffs + sfb; j++) {
isMask[j] = 0;
}
}
currentIsSfbCount = 0;
overallHrrError = FL2FXCONST_DBL(0.0f);
isRegionLoudness = FL2FXCONST_DBL(0.0f);
}
}
}
}
/*****************************************************************************
functionname: FDKaacEnc_IntensityStereoProcessing
description: Intensity stereo processing tool
input: sfbEnergyLeft
sfbEnergyRight
mdctSpectrumLeft
mdctSpectrumRight
sfbThresholdLeft
sfbThresholdRight
sfbSpreadEnLeft
sfbSpreadEnRight
sfbEnergyLdDataLeft
sfbEnergyLdDataRight
output: isBook
isScale
pnsData->pnsFlag
msDigest zeroed from start to sfbCnt
msMask zeroed from start to sfbCnt
mdctSpectrumRight zeroed where isBook!=0
sfbEnergyRight zeroed where isBook!=0
sfbSpreadEnRight zeroed where isBook!=0
sfbThresholdRight zeroed where isBook!=0
sfbEnergyLdDataRight FL2FXCONST_DBL(-1.0) where isBook!=0
sfbThresholdLdDataRight FL2FXCONST_DBL(-0.515625f) where isBook!=0
returns: none
*****************************************************************************/
void FDKaacEnc_IntensityStereoProcessing(
FIXP_DBL *sfbEnergyLeft,
FIXP_DBL *sfbEnergyRight,
FIXP_DBL *mdctSpectrumLeft,
FIXP_DBL *mdctSpectrumRight,
FIXP_DBL *sfbThresholdLeft,
FIXP_DBL *sfbThresholdRight,
FIXP_DBL *sfbThresholdLdDataRight,
FIXP_DBL *sfbSpreadEnLeft,
FIXP_DBL *sfbSpreadEnRight,
FIXP_DBL *sfbEnergyLdDataLeft,
FIXP_DBL *sfbEnergyLdDataRight,
INT *msDigest,
INT *msMask,
const INT sfbCnt,
const INT sfbPerGroup,
const INT maxSfbPerGroup,
const INT *sfbOffset,
const INT allowIS,
INT *isBook,
INT *isScale,
PNS_DATA *RESTRICT pnsData[2]
)
{
INT sfb,sfboffs, j;
FIXP_DBL scale;
FIXP_DBL lr;
FIXP_DBL hrrErr[MAX_GROUPED_SFB];
FIXP_DBL normSfbLoudness[MAX_GROUPED_SFB];
FIXP_DBL realIsScale[MAX_GROUPED_SFB];
INTENSITY_PARAMETERS isParams;
INT isMask[MAX_GROUPED_SFB];
FDKmemclear((void*)isBook,sfbCnt*sizeof(INT));
FDKmemclear((void*)isMask,sfbCnt*sizeof(INT));
FDKmemclear((void*)realIsScale,sfbCnt*sizeof(FIXP_DBL));
FDKmemclear((void*)isScale,sfbCnt*sizeof(INT));
FDKmemclear((void*)hrrErr,sfbCnt*sizeof(FIXP_DBL));
if (!allowIS)
return;
FDKaacEnc_initIsParams(&isParams);
/* compute / set the following values per SFB:
* - left/right ratio between channels
* - normalized loudness
* + loudness == average of energy in channels to 0.25
* + normalization: division by sum of all SFB loudnesses
* - isMask (is set to 0 if channels are the same or one is 0)
*/
FDKaacEnc_prepareIntensityDecision(sfbEnergyLeft,
sfbEnergyRight,
sfbEnergyLdDataLeft,
sfbEnergyLdDataRight,
mdctSpectrumLeft,
mdctSpectrumRight,
&isParams,
hrrErr,
isMask,
realIsScale,
normSfbLoudness,
sfbCnt,
sfbPerGroup,
maxSfbPerGroup,
sfbOffset);
FDKaacEnc_finalizeIntensityDecision(hrrErr,
isMask,
realIsScale,
normSfbLoudness,
&isParams,
sfbCnt,
sfbPerGroup,
maxSfbPerGroup);
for (sfb=0; sfb<sfbCnt; sfb+=sfbPerGroup) {
for (sfboffs=0; sfboffs<maxSfbPerGroup; sfboffs++) {
INT sL, sR;
FIXP_DBL inv_n;
msMask[sfb+sfboffs] = 0;
if (isMask[sfb+sfboffs] == 0) {
continue;
}
if ( (sfbEnergyLeft[sfb+sfboffs] < sfbThresholdLeft[sfb+sfboffs])
&&(fMult(FL2FXCONST_DBL(1.0f/1.5f),sfbEnergyRight[sfb+sfboffs]) > sfbThresholdRight[sfb+sfboffs]) ) {
continue;
}
/* NEW: if there is a big-enough IS region, switch off PNS */
if (pnsData[0]) {
if(pnsData[0]->pnsFlag[sfb+sfboffs]) {
pnsData[0]->pnsFlag[sfb+sfboffs] = 0;
}
if(pnsData[1]->pnsFlag[sfb+sfboffs]) {
pnsData[1]->pnsFlag[sfb+sfboffs] = 0;
}
}
inv_n = GetInvInt((sfbOffset[sfb + sfboffs + 1] - sfbOffset[sfb + sfboffs])>>1); // scaled with 2 to compensate fMultDiv2() in subsequent loop
sL = calcSfbMaxScale(mdctSpectrumLeft,sfbOffset[sfb+sfboffs],sfbOffset[sfb+sfboffs+1]);
sR = calcSfbMaxScale(mdctSpectrumRight,sfbOffset[sfb+sfboffs],sfbOffset[sfb+sfboffs+1]);
lr = FL2FXCONST_DBL(0.0f);
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++)
lr += fMultDiv2(fMultDiv2(mdctSpectrumLeft[j]<<sL,mdctSpectrumRight[j]<<sR),inv_n);
lr = lr<<1;
if (lr < FL2FXCONST_DBL(0.0f)) {
/* This means OUT OF phase intensity stereo, cf. standard */
INT s0, s1, s2;
FIXP_DBL tmp, d, ed = FL2FXCONST_DBL(0.0f);
s0 = fixMin(sL,sR);
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
d = ((mdctSpectrumLeft[j]<<s0)>>1) - ((mdctSpectrumRight[j]<<s0)>>1);
ed += fMultDiv2(d,d)>>(MDCT_SPEC_SF-1);
}
msMask[sfb+sfboffs] = 1;
tmp = fDivNorm(sfbEnergyLeft[sfb+sfboffs],ed,&s1);
s2 = (s1) + (2*s0) - 2 - MDCT_SPEC_SF;
if (s2 & 1) {
tmp = tmp>>1;
s2 = s2+1;
}
s2 = (s2>>1) + 1; // +1 compensate fMultDiv2() in subsequent loop
s2 = fixMin(fixMax(s2,-(DFRACT_BITS-1)),(DFRACT_BITS-1));
scale = sqrtFixp(tmp);
if (s2 < 0) {
s2 = -s2;
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
mdctSpectrumLeft[j] = (fMultDiv2(mdctSpectrumLeft[j],scale) - fMultDiv2(mdctSpectrumRight[j],scale)) >> s2;
mdctSpectrumRight[j] = FL2FXCONST_DBL(0.0f);
}
}
else {
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
mdctSpectrumLeft[j] = (fMultDiv2(mdctSpectrumLeft[j],scale) - fMultDiv2(mdctSpectrumRight[j],scale)) << s2;
mdctSpectrumRight[j] = FL2FXCONST_DBL(0.0f);
}
}
}
else {
/* This means IN phase intensity stereo, cf. standard */
INT s0,s1,s2;
FIXP_DBL tmp, s, es = FL2FXCONST_DBL(0.0f);
s0 = fixMin(sL,sR);
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
s = ((mdctSpectrumLeft[j]<<s0)>>1) + ((mdctSpectrumRight[j]<<s0)>>1);
es += fMultDiv2(s,s)>>(MDCT_SPEC_SF-1); // scaled 2*(mdctScale - s0 + 1) + MDCT_SPEC_SF
}
msMask[sfb+sfboffs] = 0;
tmp = fDivNorm(sfbEnergyLeft[sfb+sfboffs],es,&s1);
s2 = (s1) + (2*s0) - 2 - MDCT_SPEC_SF;
if (s2 & 1) {
tmp = tmp>>1;
s2 = s2 + 1;
}
s2 = (s2>>1) + 1; // +1 compensate fMultDiv2() in subsequent loop
s2 = fixMin(fixMax(s2,-(DFRACT_BITS-1)),(DFRACT_BITS-1));
scale = sqrtFixp(tmp);
if (s2 < 0) {
s2 = -s2;
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
mdctSpectrumLeft[j] = (fMultDiv2(mdctSpectrumLeft[j],scale) + fMultDiv2(mdctSpectrumRight[j],scale)) >> s2;
mdctSpectrumRight[j] = FL2FXCONST_DBL(0.0f);
}
}
else {
for (j=sfbOffset[sfb+sfboffs]; j<sfbOffset[sfb+sfboffs+1]; j++) {
mdctSpectrumLeft[j] = (fMultDiv2(mdctSpectrumLeft[j],scale) + fMultDiv2(mdctSpectrumRight[j],scale)) << s2;
mdctSpectrumRight[j] = FL2FXCONST_DBL(0.0f);
}
}
}
isBook[sfb+sfboffs] = CODE_BOOK_IS_IN_PHASE_NO;
if ( realIsScale[sfb+sfboffs] < FL2FXCONST_DBL(0.0f) ) {
isScale[sfb+sfboffs] = (INT)(((realIsScale[sfb+sfboffs]>>1)-FL2FXCONST_DBL(0.5f/(1<<(REAL_SCALE_SF+LD_DATA_SHIFT+1))))>>(DFRACT_BITS-1-REAL_SCALE_SF-LD_DATA_SHIFT-1)) + 1;
}
else {
isScale[sfb+sfboffs] = (INT)(((realIsScale[sfb+sfboffs]>>1)+FL2FXCONST_DBL(0.5f/(1<<(REAL_SCALE_SF+LD_DATA_SHIFT+1))))>>(DFRACT_BITS-1-REAL_SCALE_SF-LD_DATA_SHIFT-1));
}
sfbEnergyRight[sfb+sfboffs] = FL2FXCONST_DBL(0.0f);
sfbEnergyLdDataRight[sfb+sfboffs] = FL2FXCONST_DBL(-1.0f);
sfbThresholdRight[sfb+sfboffs] = FL2FXCONST_DBL(0.0f);
sfbThresholdLdDataRight[sfb+sfboffs] = FL2FXCONST_DBL(-0.515625f);
sfbSpreadEnRight[sfb+sfboffs] = FL2FXCONST_DBL(0.0f);
*msDigest = MS_SOME;
}
}
}