summaryrefslogtreecommitdiffstats
path: root/libAACdec/src/rvlcconceal.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'libAACdec/src/rvlcconceal.cpp')
-rw-r--r--libAACdec/src/rvlcconceal.cpp639
1 files changed, 639 insertions, 0 deletions
diff --git a/libAACdec/src/rvlcconceal.cpp b/libAACdec/src/rvlcconceal.cpp
new file mode 100644
index 0000000..161c336
--- /dev/null
+++ b/libAACdec/src/rvlcconceal.cpp
@@ -0,0 +1,639 @@
+/****************************************************************************
+
+ (C) Copyright Fraunhofer IIS (2004)
+ 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.
+
+
+ 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.
+
+ $Id$
+
+****************************************************************************/
+/*!
+ \file
+ \brief rvlc concealment
+ \author Josef Hoepfl
+*/
+
+#include "rvlcconceal.h"
+
+
+#include "block.h"
+#include "rvlc.h"
+
+/*---------------------------------------------------------------------------------------------
+ function: calcRefValFwd
+
+ description: The function determines the scalefactor which is closed to the scalefactorband
+ conceal_min. The same is done for intensity data and noise energies.
+-----------------------------------------------------------------------------------------------
+ output: - reference value scf
+ - reference value internsity data
+ - reference value noise energy
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+static
+void calcRefValFwd (CErRvlcInfo *pRvlc,
+ CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+ int *refIsFwd,
+ int *refNrgFwd,
+ int *refScfFwd)
+{
+ int band,bnds,group,startBand;
+ int idIs,idNrg,idScf;
+ int conceal_min,conceal_group_min;
+ int MaximumScaleFactorBands;
+
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence)
+ MaximumScaleFactorBands = 16;
+ else
+ MaximumScaleFactorBands = 64;
+
+ conceal_min = pRvlc->conceal_min % MaximumScaleFactorBands;
+ conceal_group_min = pRvlc->conceal_min / MaximumScaleFactorBands;
+
+ /* calculate first reference value for approach in forward direction */
+ idIs = idNrg = idScf = 1;
+
+ /* set reference values */
+ *refIsFwd = - SF_OFFSET;
+ *refNrgFwd = pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - SF_OFFSET - 90 - 256;
+ *refScfFwd = pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - SF_OFFSET;
+
+ startBand = conceal_min-1;
+ for (group=conceal_group_min; group >= 0; group--) {
+ for (band=startBand; band >= 0; band--) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ break;
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if (idIs) {
+ *refIsFwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ idIs=0; /* reference value has been set */
+ }
+ break;
+ case NOISE_HCB:
+ if (idNrg) {
+ *refNrgFwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ idNrg=0; /* reference value has been set */
+ }
+ break ;
+ default:
+ if (idScf) {
+ *refScfFwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ idScf=0; /* reference value has been set */
+ }
+ break;
+ }
+ }
+ startBand = pRvlc->maxSfbTransmitted-1;
+ }
+
+}
+
+/*---------------------------------------------------------------------------------------------
+ function: calcRefValBwd
+
+ description: The function determines the scalefactor which is closed to the scalefactorband
+ conceal_max. The same is done for intensity data and noise energies.
+-----------------------------------------------------------------------------------------------
+ output: - reference value scf
+ - reference value internsity data
+ - reference value noise energy
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+static
+void calcRefValBwd (CErRvlcInfo *pRvlc,
+ CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+ int *refIsBwd,
+ int *refNrgBwd,
+ int *refScfBwd)
+{
+ int band,bnds,group,startBand;
+ int idIs,idNrg,idScf;
+ int conceal_max,conceal_group_max;
+ int MaximumScaleFactorBands;
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence)
+ MaximumScaleFactorBands = 16;
+ else
+ MaximumScaleFactorBands = 64;
+
+ conceal_max = pRvlc->conceal_max % MaximumScaleFactorBands;
+ conceal_group_max = pRvlc->conceal_max / MaximumScaleFactorBands;
+
+ /* calculate first reference value for approach in backward direction */
+ idIs = idNrg = idScf = 1;
+
+ /* set reference values */
+ *refIsBwd = pRvlc->dpcm_is_last_position - SF_OFFSET;
+ *refNrgBwd = pRvlc->rev_global_gain + pRvlc->dpcm_noise_last_position - SF_OFFSET - 90 - 256 + pRvlc->dpcm_noise_nrg;
+ *refScfBwd = pRvlc->rev_global_gain - SF_OFFSET;
+
+ startBand=conceal_max+1;
+
+ /* if needed, re-set reference values */
+ for (group=conceal_group_max; group < pRvlc->numWindowGroups; group++) {
+ for (band=startBand; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ break;
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if (idIs) {
+ *refIsBwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ idIs=0; /* reference value has been set */
+ }
+ break;
+ case NOISE_HCB:
+ if (idNrg) {
+ *refNrgBwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ idNrg=0; /* reference value has been set */
+ }
+ break ;
+ default:
+ if (idScf) {
+ *refScfBwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ idScf=0; /* reference value has been set */
+ }
+ break;
+ }
+ }
+ startBand=0;
+ }
+
+}
+
+
+/*---------------------------------------------------------------------------------------------
+ function: BidirectionalEstimation_UseLowerScfOfCurrentFrame
+
+ description: This approach by means of bidirectional estimation is generally performed when
+ a single bit error has been detected, the bit error can be isolated between
+ 'conceal_min' and 'conceal_max' and the 'sf_concealment' flag is not set. The
+ sets of scalefactors decoded in forward and backward direction are compared
+ with each other. The smaller scalefactor will be considered as the correct one
+ respectively. The reconstruction of the scalefactors with this approach archieve
+ good results in audio quality. The strategy must be applied to scalefactors,
+ intensity data and noise energy seperately.
+-----------------------------------------------------------------------------------------------
+ output: Concealed scalefactor, noise energy and intensity data between conceal_min and
+ conceal_max
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+void BidirectionalEstimation_UseLowerScfOfCurrentFrame (CAacDecoderChannelInfo *pAacDecoderChannelInfo)
+{
+ CErRvlcInfo *pRvlc = &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo;
+ int band,bnds,startBand,endBand,group;
+ int conceal_min,conceal_max;
+ int conceal_group_min,conceal_group_max;
+ int MaximumScaleFactorBands;
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence) {
+ MaximumScaleFactorBands = 16;
+ }
+ else {
+ MaximumScaleFactorBands = 64;
+ }
+
+ /* If an error was detected just in forward or backward direction, set the corresponding border for concealment to a
+ appropriate scalefactor band. The border is set to first or last sfb respectively, because the error will possibly
+ not follow directly after the corrupt bit but just after decoding some more (wrong) scalefactors. */
+ if (pRvlc->conceal_min == CONCEAL_MIN_INIT)
+ pRvlc->conceal_min = 0;
+
+ if (pRvlc->conceal_max == CONCEAL_MAX_INIT)
+ pRvlc->conceal_max = (pRvlc->numWindowGroups-1)*16+pRvlc->maxSfbTransmitted-1;
+
+ conceal_min = pRvlc->conceal_min % MaximumScaleFactorBands;
+ conceal_group_min = pRvlc->conceal_min / MaximumScaleFactorBands;
+ conceal_max = pRvlc->conceal_max % MaximumScaleFactorBands;
+ conceal_group_max = pRvlc->conceal_max / MaximumScaleFactorBands;
+
+ if (pRvlc->conceal_min == pRvlc->conceal_max) {
+
+ int refIsFwd,refNrgFwd,refScfFwd;
+ int refIsBwd,refNrgBwd,refScfBwd;
+
+ bnds = pRvlc->conceal_min;
+ calcRefValFwd(pRvlc,pAacDecoderChannelInfo,&refIsFwd,&refNrgFwd,&refScfFwd);
+ calcRefValBwd(pRvlc,pAacDecoderChannelInfo,&refIsBwd,&refNrgBwd,&refScfBwd);
+
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ break;
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if (refIsFwd < refIsBwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refIsFwd;
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refIsBwd;
+ break;
+ case NOISE_HCB:
+ if (refNrgFwd < refNrgBwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refNrgFwd;
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refNrgBwd;
+ break;
+ default:
+ if (refScfFwd < refScfBwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refScfFwd;
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = refScfBwd;
+ break;
+ }
+ }
+ else {
+ pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[pRvlc->conceal_max] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[pRvlc->conceal_max];
+ pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[pRvlc->conceal_min] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[pRvlc->conceal_min];
+
+ /* consider the smaller of the forward and backward decoded value as the correct one */
+ startBand = conceal_min;
+ if (conceal_group_min == conceal_group_max)
+ endBand = conceal_max;
+ else
+ endBand = pRvlc->maxSfbTransmitted-1;
+
+ for (group=conceal_group_min; group <= conceal_group_max; group++) {
+ for (band=startBand; band <= endBand; band++) {
+ bnds = 16*group+band;
+ if (pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds] < pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds])
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ }
+ startBand = 0;
+ if ((group+1) == conceal_group_max)
+ endBand = conceal_max;
+ }
+ }
+
+ /* now copy all data to the output buffer which needs not to be concealed */
+ if (conceal_group_min == 0)
+ endBand = conceal_min;
+ else
+ endBand = pRvlc->maxSfbTransmitted;
+ for (group=0; group <= conceal_group_min; group++) {
+ for (band=0; band < endBand; band++) {
+ bnds = 16*group+band;
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ }
+ if ((group+1) == conceal_group_min)
+ endBand = conceal_min;
+ }
+
+ startBand = conceal_max+1;
+ for (group=conceal_group_max; group < pRvlc->numWindowGroups; group++) {
+ for (band=startBand; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ }
+ startBand = 0;
+ }
+}
+
+/*---------------------------------------------------------------------------------------------
+ function: BidirectionalEstimation_UseScfOfPrevFrameAsReference
+
+ description: This approach by means of bidirectional estimation is generally performed when
+ a single bit error has been detected, the bit error can be isolated between
+ 'conceal_min' and 'conceal_max', the 'sf_concealment' flag is set and the
+ previous frame has the same block type as the current frame. The scalefactor
+ decoded in forward and backward direction and the scalefactor of the previous
+ frame are compared with each other. The smaller scalefactor will be considered
+ as the correct one. At this the codebook of the previous and current frame must
+ be of the same set (scf, nrg, is) in each scalefactorband. Otherwise the
+ scalefactor of the previous frame is not considered in the minimum calculation.
+ The reconstruction of the scalefactors with this approach archieve good results
+ in audio quality. The strategy must be applied to scalefactors, intensity data
+ and noise energy seperately.
+-----------------------------------------------------------------------------------------------
+ output: Concealed scalefactor, noise energy and intensity data between conceal_min and
+ conceal_max
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+void BidirectionalEstimation_UseScfOfPrevFrameAsReference (
+ CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+ CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo
+ )
+{
+ CErRvlcInfo *pRvlc = &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo;
+ int band,bnds,startBand,endBand,group;
+ int conceal_min,conceal_max;
+ int conceal_group_min,conceal_group_max;
+ int MaximumScaleFactorBands;
+ int commonMin;
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence) {
+ MaximumScaleFactorBands = 16;
+ }
+ else {
+ MaximumScaleFactorBands = 64;
+ }
+
+ /* If an error was detected just in forward or backward direction, set the corresponding border for concealment to a
+ appropriate scalefactor band. The border is set to first or last sfb respectively, because the error will possibly
+ not follow directly after the corrupt bit but just after decoding some more (wrong) scalefactors. */
+ if (pRvlc->conceal_min == CONCEAL_MIN_INIT)
+ pRvlc->conceal_min = 0;
+
+ if (pRvlc->conceal_max == CONCEAL_MAX_INIT)
+ pRvlc->conceal_max = (pRvlc->numWindowGroups-1)*16+pRvlc->maxSfbTransmitted-1;
+
+ conceal_min = pRvlc->conceal_min % MaximumScaleFactorBands;
+ conceal_group_min = pRvlc->conceal_min / MaximumScaleFactorBands;
+ conceal_max = pRvlc->conceal_max % MaximumScaleFactorBands;
+ conceal_group_max = pRvlc->conceal_max / MaximumScaleFactorBands;
+
+ pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[pRvlc->conceal_max] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[pRvlc->conceal_max];
+ pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[pRvlc->conceal_min] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[pRvlc->conceal_min];
+
+ /* consider the smaller of the forward and backward decoded value as the correct one */
+ startBand = conceal_min;
+ if (conceal_group_min == conceal_group_max)
+ endBand = conceal_max;
+ else
+ endBand = pRvlc->maxSfbTransmitted-1;
+
+ for (group=conceal_group_min; group <= conceal_group_max; group++) {
+ for (band=startBand; band <= endBand; band++) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = 0;
+ break;
+
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==INTENSITY_HCB) || (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==INTENSITY_HCB2) ) {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ }
+ else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ }
+ break;
+
+ case NOISE_HCB:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==NOISE_HCB) ) {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ } else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ }
+ break;
+
+ default:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=ZERO_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=NOISE_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=INTENSITY_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=INTENSITY_HCB2) )
+ {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ } else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ }
+ break;
+ }
+ }
+ startBand = 0;
+ if ((group+1) == conceal_group_max)
+ endBand = conceal_max;
+ }
+
+ /* now copy all data to the output buffer which needs not to be concealed */
+ if (conceal_group_min == 0)
+ endBand = conceal_min;
+ else
+ endBand = pRvlc->maxSfbTransmitted;
+ for (group=0; group <= conceal_group_min; group++) {
+ for (band=0; band < endBand; band++) {
+ bnds = 16*group+band;
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ }
+ if ((group+1) == conceal_group_min)
+ endBand = conceal_min;
+ }
+
+ startBand = conceal_max+1;
+ for (group=conceal_group_max; group < pRvlc->numWindowGroups; group++) {
+ for (band=startBand; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ }
+ startBand = 0;
+ }
+}
+
+/*---------------------------------------------------------------------------------------------
+ function: StatisticalEstimation
+
+ description: This approach by means of statistical estimation is generally performed when
+ both the start value and the end value are different and no further errors have
+ been detected. Considering the forward and backward decoded scalefactors, the
+ set with the lower scalefactors in sum will be considered as the correct one.
+ The scalefactors are differentially encoded. Normally it would reach to compare
+ one pair of the forward and backward decoded scalefactors to specify the lower
+ set. But having detected no further errors does not necessarily mean the absence
+ of errors. Therefore all scalefactors decoded in forward and backward direction
+ are summed up seperately. The set with the lower sum will be used. The strategy
+ must be applied to scalefactors, intensity data and noise energy seperately.
+-----------------------------------------------------------------------------------------------
+ output: Concealed scalefactor, noise energy and intensity data
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+void StatisticalEstimation (CAacDecoderChannelInfo *pAacDecoderChannelInfo)
+{
+ CErRvlcInfo *pRvlc = &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo;
+ int band,bnds,group;
+ int sumIsFwd,sumIsBwd; /* sum of intensity data forward/backward */
+ int sumNrgFwd,sumNrgBwd; /* sum of noise energy data forward/backward */
+ int sumScfFwd,sumScfBwd; /* sum of scalefactor data forward/backward */
+ int useIsFwd,useNrgFwd,useScfFwd; /* the flags signals the elements which are used for the final result */
+ int MaximumScaleFactorBands;
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence)
+ MaximumScaleFactorBands = 16;
+ else
+ MaximumScaleFactorBands = 64;
+
+ sumIsFwd = sumIsBwd = sumNrgFwd = sumNrgBwd = sumScfFwd = sumScfBwd = 0;
+ useIsFwd = useNrgFwd = useScfFwd = 0;
+
+ /* calculate sum of each group (scf,nrg,is) of forward and backward direction */
+ for (group=0; group<pRvlc->numWindowGroups; group++) {
+ for (band=0; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ break;
+
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ sumIsFwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ sumIsBwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break;
+
+ case NOISE_HCB:
+ sumNrgFwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ sumNrgBwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break ;
+
+ default:
+ sumScfFwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ sumScfBwd += pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break;
+ }
+ }
+ }
+
+ /* find for each group (scf,nrg,is) the correct direction */
+ if ( sumIsFwd < sumIsBwd )
+ useIsFwd = 1;
+
+ if ( sumNrgFwd < sumNrgBwd )
+ useNrgFwd = 1;
+
+ if ( sumScfFwd < sumScfBwd )
+ useScfFwd = 1;
+
+ /* conceal each group (scf,nrg,is) */
+ for (group=0; group<pRvlc->numWindowGroups; group++) {
+ for (band=0; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ break;
+
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if (useIsFwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break;
+
+ case NOISE_HCB:
+ if (useNrgFwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break ;
+
+ default:
+ if (useScfFwd)
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds];
+ else
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds];
+ break;
+ }
+ }
+ }
+}
+
+
+/*---------------------------------------------------------------------------------------------
+ description: Approach by means of predictive interpolation
+ This approach by means of predictive estimation is generally performed when
+ the error cannot be isolated between 'conceal_min' and 'conceal_max', the
+ 'sf_concealment' flag is set and the previous frame has the same block type
+ as the current frame. Check for each scalefactorband if the same type of data
+ (scalefactor, internsity data, noise energies) is transmitted. If so use the
+ scalefactor (intensity data, noise energy) in the current frame. Otherwise set
+ the scalefactor (intensity data, noise energy) for this scalefactorband to zero.
+-----------------------------------------------------------------------------------------------
+ output: Concealed scalefactor, noise energy and intensity data
+-----------------------------------------------------------------------------------------------
+ return: -
+-------------------------------------------------------------------------------------------- */
+
+void PredictiveInterpolation (
+ CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+ CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo
+ )
+{
+ CErRvlcInfo *pRvlc = &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo;
+ int band,bnds,group;
+ int MaximumScaleFactorBands;
+ int commonMin;
+
+ if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == EightShortSequence)
+ MaximumScaleFactorBands = 16;
+ else
+ MaximumScaleFactorBands = 64;
+
+ for (group=0; group<pRvlc->numWindowGroups; group++) {
+ for (band=0; band < pRvlc->maxSfbTransmitted; band++) {
+ bnds = 16*group+band;
+ switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) {
+ case ZERO_HCB:
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = 0;
+ break;
+
+ case INTENSITY_HCB:
+ case INTENSITY_HCB2:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==INTENSITY_HCB) || (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==INTENSITY_HCB2) ) {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ }
+ else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = -110;
+ }
+ break;
+
+ case NOISE_HCB:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]==NOISE_HCB) ) {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ }
+ else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = -110;
+ }
+ break;
+
+ default:
+ if ( (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=ZERO_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=NOISE_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=INTENSITY_HCB)
+ && (pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousCodebook[bnds]!=INTENSITY_HCB2) ) {
+ commonMin = FDKmin(pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds],pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd[bnds]);
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = FDKmin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo.aRvlcPreviousScaleFactor[bnds]);
+ }
+ else {
+ pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = 0;
+ }
+ break;
+ }
+ }
+ }
+}
+