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Diffstat (limited to 'libAACdec/src/rvlcconceal.cpp')
| -rw-r--r-- | libAACdec/src/rvlcconceal.cpp | 697 |
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diff --git a/libAACdec/src/rvlcconceal.cpp b/libAACdec/src/rvlcconceal.cpp deleted file mode 100644 index ae6b4da..0000000 --- a/libAACdec/src/rvlcconceal.cpp +++ /dev/null @@ -1,697 +0,0 @@ - -/* ----------------------------------------------------------------------------------------------------------- -Software License for The Fraunhofer FDK AAC Codec Library for Android - -© Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. - 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 ------------------------------------------------------------------------------------------------------------ */ - -/*! - \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; - } - } - } -} - |