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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; groupnumWindowGroups; 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; groupnumWindowGroups; 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; groupnumWindowGroups; 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; } } } }