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Diffstat (limited to 'fdk-aac/libAACdec/src/rvlcconceal.cpp')
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diff --git a/fdk-aac/libAACdec/src/rvlcconceal.cpp b/fdk-aac/libAACdec/src/rvlcconceal.cpp new file mode 100644 index 0000000..77fda68 --- /dev/null +++ b/fdk-aac/libAACdec/src/rvlcconceal.cpp @@ -0,0 +1,787 @@ +/* ----------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2018 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 +----------------------------------------------------------------------------- */ + +/**************************** AAC decoder library ****************************** + + Author(s): + + Description: + +*******************************************************************************/ + +/*! + \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) == BLOCK_SHORT) + 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) == BLOCK_SHORT) + 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) == BLOCK_SHORT) { + 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; + SHORT commonMin; + + if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == BLOCK_SHORT) { + 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 = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousScaleFactor[bnds]); + } else { + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + } + break; + + case NOISE_HCB: + if (pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousCodebook[bnds] == NOISE_HCB) { + commonMin = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousScaleFactor[bnds]); + } else { + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = fMin( + 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 = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousScaleFactor[bnds]); + } else { + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = fMin( + 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 */ + + 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; + SHORT commonMin; + + 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 = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousScaleFactor[bnds]); + } else { + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = -110; + } + break; + + case NOISE_HCB: + if (pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousCodebook[bnds] == NOISE_HCB) { + commonMin = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(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 = fMin( + pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds], + pAacDecoderChannelInfo->pComData->overlay.aac + .aRvlcScfBwd[bnds]); + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = + fMin(commonMin, pAacDecoderStaticChannelInfo->concealmentInfo + .aRvlcPreviousScaleFactor[bnds]); + } else { + pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = 0; + } + break; + } + } + } +} |