/* bitAllocation.cpp - source file for class needed for psychoacoustic bit-allocation * written by C. R. Helmrich, last modified in 2020 - see License.htm for legal notices * * The copyright in this software is being made available under a Modified BSD-Style License * and comes with ABSOLUTELY NO WARRANTY. This software may be subject to other third- * party rights, including patent rights. No such rights are granted under this License. * * Copyright (c) 2018-2020 Christian R. Helmrich, project ecodis. All rights reserved. */ #include "exhaleLibPch.h" #include "bitAllocation.h" // static helper functions static inline uint32_t intSqrt (const uint32_t val) { return uint32_t (0.5 + sqrt ((double) val)); } static inline uint32_t jndModel (const uint32_t val, const uint32_t mean, const unsigned expTimes512, const unsigned mulTimes512) { const double exp = (double) expTimes512 / 512.0; // exponent const double mul = (double) mulTimes512 / 512.0; // a factor const double res = pow (mul * (double) val, exp) * pow ((double) mean, 1.0 - exp); return uint32_t (__min ((double) UINT_MAX, res + 0.5)); } static inline uint32_t squareMeanRoot (const uint32_t value1, const uint32_t value2) { const double meanRoot = (sqrt ((double) value1) + sqrt ((double) value2)) * 0.5; return uint32_t (meanRoot * meanRoot + 0.5); } static void jndPowerLawAndPeakSmoothing (uint32_t* const stepSizes, const unsigned nStepSizes, const uint32_t avgStepSize, const uint8_t sfm, const uint8_t tfm) { const unsigned expTimes512 = 512u - sfm; // 1.0 - sfm / 2.0 const unsigned mulTimes512 = __min (expTimes512, 512u - tfm); uint32_t stepSizeM3 = 0, stepSizeM2 = 0, stepSizeM1 = BA_EPS; // hearing threshold around zero Hz unsigned b; for (b = 0; b < __min (2, nStepSizes); b++) { stepSizeM3 = stepSizeM2; stepSizeM2 = stepSizeM1; stepSizeM1 = stepSizes[b] = jndModel (stepSizes[b], avgStepSize, expTimes512, mulTimes512); } stepSizes[0] = __min (stepSizeM1, stepSizes[0]); // `- becomes -- for (/*b*/; b < nStepSizes; b++) { const uint64_t oneMinusB = 128 - b; const uint32_t stepSizeB = jndModel (stepSizes[b], avgStepSize, expTimes512, mulTimes512); if ((stepSizeM3 <= stepSizeM2) && (stepSizeM3 <= stepSizeM1) && (stepSizeB <= stepSizeM2) && (stepSizeB <= stepSizeM1)) { const uint32_t maxM3M0 = __max (stepSizeM3, stepSizeB); // smoothen local spectral peak of _´`- shape stepSizes[b - 2] = uint32_t ((b * (uint64_t) stepSizes[b - 2] + oneMinusB * __min (maxM3M0, stepSizes[b - 2]) + 64) >> 7); // _-`- stepSizes[b - 1] = uint32_t ((b * (uint64_t) stepSizes[b - 1] + oneMinusB * __min (maxM3M0, stepSizes[b - 1]) + 64) >> 7); // _--- } stepSizeM3 = stepSizeM2; stepSizeM2 = stepSizeM1; stepSizeM1 = (stepSizes[b] = stepSizeB); // modified step-size may be smoothened in next loop iteration } } // constructor BitAllocator::BitAllocator () { for (unsigned ch = 0; ch < USAC_MAX_NUM_CHANNELS; ch++) { m_avgStepSize[ch] = 0; m_avgSpecFlat[ch] = 0; m_avgTempFlat[ch] = 0; } m_rateIndex = 0; m_tempSfbValue = nullptr; m_tnsPredictor = nullptr; } // public functions void BitAllocator::getChAverageSpecFlat (uint8_t meanSpecFlatInCh[USAC_MAX_NUM_CHANNELS], const unsigned nChannels) { if ((meanSpecFlatInCh == nullptr) || (nChannels > USAC_MAX_NUM_CHANNELS)) { return; } memcpy (meanSpecFlatInCh, m_avgSpecFlat, nChannels * sizeof (uint8_t)); } void BitAllocator::getChAverageTempFlat (uint8_t meanTempFlatInCh[USAC_MAX_NUM_CHANNELS], const unsigned nChannels) { if ((meanTempFlatInCh == nullptr) || (nChannels > USAC_MAX_NUM_CHANNELS)) { return; } memcpy (meanTempFlatInCh, m_avgTempFlat, nChannels * sizeof (uint8_t)); } uint8_t BitAllocator::getScaleFac (const uint32_t sfbStepSize, const int32_t* const sfbSignal, const uint8_t sfbWidth, const uint32_t sfbRmsValue) { uint8_t sf; uint32_t u; #if !RESTRICT_TO_AAC uint64_t meanSpecLoudness = 0; double d; #endif if ((sfbSignal == nullptr) || (sfbWidth == 0) || (sfbRmsValue < 46)) { return 0; // use lowest scale factor } #if RESTRICT_TO_AAC u = 0; for (sf = 0; sf < sfbWidth; sf++) { u += intSqrt (abs (sfbSignal[sf])); } u = uint32_t ((u * 16384ui64 + (sfbWidth >> 1)) / sfbWidth); u = uint32_t (0.5 + sqrt ((double) u) * 128.0); if (u < 42567) return 0; u = uint32_t ((sfbStepSize * 42567ui64 + (u >> 1)) / u); sf = (u > 1 ? uint8_t (0.5 + 17.7169498394 * log10 ((double) u)) : 4); #else for (sf = 0; sf < sfbWidth; sf++) // simple, low-complexity derivation method for USAC's arithmetic coder { const int64_t temp = ((int64_t) sfbSignal[sf] + 8) >> 4; // avoid overflow meanSpecLoudness += temp * temp; } meanSpecLoudness = uint64_t (0.5 + pow (256.0 * (double) meanSpecLoudness / sfbWidth, 0.25)); u = uint32_t (0.5 + pow ((double) sfbRmsValue, 0.75) * 256.0); // u = 2^8 * (sfbRmsValue^0.75) u = uint32_t ((meanSpecLoudness * sfbStepSize * 665 + (u >> 1)) / u); // u = sqrt(6.75) * m*thr/u d = (u > 1 ? log10 ((double) u) : 0.25); u = uint32_t (0.5 + pow ((double) sfbRmsValue, 0.25) * 16384.0); // u = 2^14 * (sfbRmsValue^0.25) u = uint32_t (((uint64_t) sfbStepSize * 42567 + (u >> 1)) / u); // u = sqrt(6.75) * thr/u d += (u > 1 ? log10 ((double) u) : 0.25); sf = uint8_t (0.5 + 8.8584749197 * d); // sf = (8/3) * log2(u1*u2) = (8/3) * (log2(u1)+log2(u2)) #endif return __min (SCHAR_MAX, sf); } unsigned BitAllocator::initAllocMemory (LinearPredictor* const linPredictor, const uint8_t numSwb, const uint8_t bitRateMode) { if (linPredictor == nullptr) { return 1; // invalid arguments error } m_rateIndex = bitRateMode; m_tnsPredictor = linPredictor; if ((m_tempSfbValue = (uint8_t*) malloc (__max (MAX_PREDICTION_ORDER * sizeof (short), numSwb) * sizeof (uint8_t))) == nullptr) { return 2; // memory allocation error } return 0; // no error } unsigned BitAllocator::initSfbStepSizes (const SfbGroupData* const groupData[USAC_MAX_NUM_CHANNELS], const uint8_t numSwbShort, const uint32_t specAnaStats[USAC_MAX_NUM_CHANNELS], const uint32_t tempAnaStats[USAC_MAX_NUM_CHANNELS], const unsigned nChannels, const unsigned samplingRate, uint32_t* const sfbStepSizes, const unsigned lfeChannelIndex /*= USAC_MAX_NUM_CHANNELS*/, const bool tnsDisabled /*= false*/) { // equal-loudness weighting based on data from: K. Kurakata, T. Mizunami, and K. Matsushita, "Percentiles // of Normal Hearing-Threshold Distribution Under Free-Field Listening Conditions in Numerical Form," Ac. // Sci. Tech, vol. 26, no. 5, pp. 447-449, Jan. 2005, https://www.researchgate.net/publication/239433096. const unsigned HF/*idx*/= ((123456 - samplingRate) >> 11) + (samplingRate < 37566 ? 2 : 0); // start SFB const unsigned LF/*idx*/= 9; const unsigned MF/*idx*/= (samplingRate < 27713 ? HF : __min (HF, 30u)); const unsigned msShift = (samplingRate + 36736) >> 15; // TODO: 768 smp const unsigned msOffset = 1 << (msShift - 1); uint32_t nMeans = 0, sumMeans = 0; if ((groupData == nullptr) || (specAnaStats == nullptr) || (tempAnaStats == nullptr) || (sfbStepSizes == nullptr) || (numSwbShort < MIN_NUM_SWB_SHORT) || (numSwbShort > MAX_NUM_SWB_SHORT) || (nChannels > USAC_MAX_NUM_CHANNELS) || (samplingRate < 7350) || (samplingRate > 96000) || (lfeChannelIndex > USAC_MAX_NUM_CHANNELS)) { return 1; // invalid arguments error } for (unsigned ch = 0; ch < nChannels; ch++) { const SfbGroupData& grpData = *groupData[ch]; const uint32_t maxSfbInCh = __min (MAX_NUM_SWB_LONG, grpData.sfbsPerGroup); const uint32_t nBandsInCh = grpData.numWindowGroups * maxSfbInCh; const uint32_t* rms = grpData.sfbRmsValues; uint32_t* stepSizes = &sfbStepSizes[ch * numSwbShort * NUM_WINDOW_GROUPS]; // --- apply INTRA-channel simultaneous masking, equal-loudness weighting, and thresholding to SFB RMS data uint32_t maskingSlope = 0, gr, b, elw = 58254; // 8/9 uint32_t rmsEqualLoud = 0; uint32_t sumStepSizes = 0; m_avgStepSize[ch] = 0; b = ((specAnaStats[ch] >> 16) & UCHAR_MAX); // start with squared spec. flatness from spectral analysis b = __max (b * b, (tempAnaStats[ch] >> 24) * (tempAnaStats[ch] >> 24)); // ..and from temporal analysis m_avgSpecFlat[ch] = uint8_t ((b + (1 << 7)) >> 8); // normalized maximum b = ((tempAnaStats[ch] >> 16) & UCHAR_MAX); // now derive squared temp. flatness from temporal analysis b = __max (b * b, (specAnaStats[ch] >> 24) * (specAnaStats[ch] >> 24)); // ..and from spectral analysis m_avgTempFlat[ch] = uint8_t ((b + (1 << 7)) >> 8); // normalized maximum if ((nBandsInCh == 0) || (grpData.numWindowGroups > NUM_WINDOW_GROUPS)) { continue; } if ((ch == lfeChannelIndex) || (grpData.numWindowGroups != 1)) // LFE, SHORT windows: no masking or ELW { for (gr = 0; gr < grpData.numWindowGroups; gr++) { const uint32_t* gRms = &rms[numSwbShort * gr]; uint32_t* gStepSizes = &stepSizes[numSwbShort * gr]; for (b = numSwbShort - 1; b >= maxSfbInCh; b--) { gStepSizes[b] = 0; } for (/*b*/; b > 0; b--) { gStepSizes[b] = __max (gRms[b], BA_EPS); sumStepSizes += intSqrt (gStepSizes[b]); } gStepSizes[0] = __max (gRms[0], BA_EPS); sumStepSizes += intSqrt (gStepSizes[0]); } // for gr if (ch != lfeChannelIndex) { // --- SHORT windows: apply perceptual just noticeable difference (JND) model and local band-peak smoothing nMeans++; for (b = maxSfbInCh - 1; b > 0; b--) // gentle temporal band-peak smoothing; a spectral one follows { uint32_t maxGrpStep = stepSizes[b], stepSizeM1 = BA_EPS; for (gr = 1; gr < grpData.numWindowGroups; gr++) { const uint32_t curGrpStep = stepSizes[b + numSwbShort * gr]; if (curGrpStep > maxGrpStep) maxGrpStep = curGrpStep; } for (gr = 0; gr < grpData.numWindowGroups; gr++) { const uint32_t newGrpStep = __max (stepSizeM1, (gr + 1 == grpData.numWindowGroups ? BA_EPS : stepSizes[b + numSwbShort * (gr + 1)])); stepSizeM1 = stepSizes[b + numSwbShort * gr]; if ((stepSizeM1 == maxGrpStep) && (maxGrpStep > newGrpStep)) { const uint32_t sqrtOldStep = intSqrt (maxGrpStep); const uint32_t sqrtNewStep = intSqrt (newGrpStep); uint32_t& gStepSize = stepSizes[b + numSwbShort * gr]; sumStepSizes += (gStepSize = (sqrtOldStep + sqrtNewStep) >> 1) - sqrtOldStep; gStepSize *= gStepSize; // for square-mean-root } } } // for b m_avgStepSize[ch] = __min (USHRT_MAX, (sumStepSizes + (nBandsInCh >> 1)) / nBandsInCh); sumMeans += m_avgStepSize[ch]; m_avgStepSize[ch] *= m_avgStepSize[ch]; for (gr = 0; gr < grpData.numWindowGroups; gr++) // separate spectral peak smoothing for each group { jndPowerLawAndPeakSmoothing (&stepSizes[numSwbShort * gr], maxSfbInCh, m_avgStepSize[ch], m_avgSpecFlat[ch], 0); } } continue; } stepSizes[0] = __max (rms[0], BA_EPS); for (b = 1; b < __min (LF, maxSfbInCh); b++) // apply steeper low-frequency simultaneous masking slopes { maskingSlope = (stepSizes[b - 1] + (msOffset << (9u - b))) >> (msShift + 9u - b); stepSizes[b] = __max (rms[b], maskingSlope + BA_EPS); } for (/*b*/; b < __min (MF, maxSfbInCh); b++) // apply typical mid-frequency simultaneous masking slopes { maskingSlope = (stepSizes[b - 1] + msOffset) >> msShift; stepSizes[b] = __max (rms[b], maskingSlope + BA_EPS); } if ((samplingRate >= 27713) && (samplingRate < 75132)) { for (/*b*/; b < __min (HF, maxSfbInCh); b++) // compensate high-frequency slopes for linear SFB width { maskingSlope = ((uint64_t) stepSizes[b - 1] * (9u + b - MF) + (msOffset << 3u)) >> (msShift + 3u); stepSizes[b] = __max (rms[b], maskingSlope + BA_EPS); } for (/*b = HF region*/; b < maxSfbInCh; b++) // apply extra high-frequency equal-loudness attenuation { for (unsigned d = b - HF; d > 0; d--) { elw = (elw * 52430 - SHRT_MIN) >> 16; // elw *= 4/5 } rmsEqualLoud = uint32_t (((uint64_t) rms[b] * elw - SHRT_MIN) >> 16); // equal loudness weighting maskingSlope = ((uint64_t) stepSizes[b - 1] * (9u + b - MF) + (msOffset << 3u)) >> (msShift + 3u); stepSizes[b] = __max (rmsEqualLoud, maskingSlope + BA_EPS); } } else // no equal-loudness weighting for low or high rates { for (/*b = MF region*/; b < maxSfbInCh; b++) // compensate high-frequency slopes for linear SFB width { maskingSlope = ((uint64_t) stepSizes[b - 1] * (9u + b - MF) + (msOffset << 3u)) >> (msShift + 3u); stepSizes[b] = __max (rms[b], maskingSlope + BA_EPS); } } stepSizes[b] = 0; for (b -= 1; b > __min (MF, maxSfbInCh); b--) // complete simultaneous masking by reversing the pattern { sumStepSizes += intSqrt (stepSizes[b]); maskingSlope = ((uint64_t) stepSizes[b] * (8u + b - MF) + (msOffset << 3u)) >> (msShift + 3u); stepSizes[b - 1] = __max (stepSizes[b - 1], maskingSlope); } for (/*b*/; b > __min (LF, maxSfbInCh); b--) // typical reversed mid-freq. simultaneous masking slopes { sumStepSizes += intSqrt (stepSizes[b]); maskingSlope = (stepSizes[b] + msOffset) >> msShift; stepSizes[b - 1] = __max (stepSizes[b - 1], maskingSlope); } for (/*b = min (9, maxSfbInCh)*/; b > 0; b--) // steeper reversed low-freq. simultaneous masking slopes { sumStepSizes += intSqrt (stepSizes[b]); maskingSlope = (stepSizes[b] + (msOffset << (10u - b))) >> (msShift + 10u - b); stepSizes[b - 1] = __max (stepSizes[b - 1], maskingSlope); } sumStepSizes += intSqrt (stepSizes[0]); // --- LONG window: apply perceptual JND model and local band-peak smoothing, undo equal-loudness weighting nMeans++; m_avgStepSize[ch] = __min (USHRT_MAX, (sumStepSizes + (nBandsInCh >> 1)) / nBandsInCh); sumMeans += m_avgStepSize[ch]; m_avgStepSize[ch] *= m_avgStepSize[ch]; jndPowerLawAndPeakSmoothing (stepSizes, maxSfbInCh, m_avgStepSize[ch], m_avgSpecFlat[ch], tnsDisabled ? m_avgTempFlat[ch] : 0); if ((samplingRate >= 27713) && (samplingRate < 75132)) { elw = 36; // 36/32 = 9/8 for (b = HF; b < maxSfbInCh; b++) // undo above additional high-frequency equal-loudness attenuation { for (unsigned d = b - HF; d > 0; d--) { elw = (16u + elw * 40) >> 5; // inverse elw *= 5/4. NOTE: this may overflow for 64 kHz, that's OK } if (elw == 138 || elw >= 1024) elw--; rmsEqualLoud = uint32_t (__min (UINT_MAX, (16u + (uint64_t) stepSizes[b] * elw) >> 5)); stepSizes[b] = rmsEqualLoud; } } } // for ch if ((nMeans < 2) || (sumMeans <= nMeans * BA_EPS)) // in case of one channel or low-RMS input, we're done { return 0; // no error } sumMeans = (sumMeans + (nMeans >> 1)) / nMeans; sumMeans *= sumMeans; // since we've averaged square-roots #if BA_INTER_CHAN_SIM_MASK if (nMeans > 3) { // TODO: cross-channel simultaneous masking for 4.0 - 7.1 } #endif for (unsigned ch = 0; ch < nChannels; ch++) { const SfbGroupData& grpData = *groupData[ch]; const uint32_t maxSfbInCh = __min (MAX_NUM_SWB_LONG, grpData.sfbsPerGroup); const uint32_t nBandsInCh = grpData.numWindowGroups * maxSfbInCh; const uint32_t chStepSize = m_avgStepSize[ch]; uint32_t* stepSizes = &sfbStepSizes[ch * numSwbShort * NUM_WINDOW_GROUPS]; // --- apply INTER-channel simultaneous masking and JND modeling to calculated INTRA-channel step-size data uint64_t mAvgStepSize; // modified and averaged step-size if ((nBandsInCh == 0) || (grpData.numWindowGroups > NUM_WINDOW_GROUPS) || (ch == lfeChannelIndex)) { continue; } mAvgStepSize = jndModel (chStepSize, sumMeans, 7 << 6 /*7/8*/, 512); for (unsigned gr = 0; gr < grpData.numWindowGroups; gr++) { uint32_t* gStepSizes = &stepSizes[numSwbShort * gr]; for (unsigned b = 0; b < maxSfbInCh; b++) { gStepSizes[b] = uint32_t (__min (UINT_MAX, (mAvgStepSize * gStepSizes[b] + (chStepSize >> 1)) / chStepSize)); } } // for gr m_avgStepSize[ch] = (uint32_t) mAvgStepSize; } // for ch return 0; // no error } unsigned BitAllocator::imprSfbStepSizes (const SfbGroupData* const groupData[USAC_MAX_NUM_CHANNELS], const uint8_t numSwbShort, const int32_t* const mdctSpec[USAC_MAX_NUM_CHANNELS], const unsigned nSamplesInFrame, const unsigned nChannels, const unsigned samplingRate, uint32_t* const sfbStepSizes, const unsigned firstChannelIndex, const uint8_t* const sfm, const bool commonWindow, const uint8_t* const sfbStereoData /*= nullptr*/, const uint8_t stereoConfig /*= 0*/) { const uint8_t maxSfbL16k = 16 + __min (35, (9 << 17) / __max (1, samplingRate)); // SFB index at 15.8 kHz const uint32_t redFactor = __max ((samplingRate < 27713 ? 2 : 1), __min (3, m_rateIndex)) - (stereoConfig >> 3); const uint32_t redWeight = __min (4, 9 - __min (9, m_rateIndex)); short* const tempCoeffs = (short* const) m_tempSfbValue; if ((groupData == nullptr) || (mdctSpec == nullptr) || (sfbStepSizes == nullptr) || (sfm == nullptr) || (nSamplesInFrame > 2048) || (numSwbShort < MIN_NUM_SWB_SHORT) || (numSwbShort > MAX_NUM_SWB_SHORT) || (nChannels > USAC_MAX_NUM_CHANNELS) || (samplingRate < 7350) || (samplingRate > 96000) || (firstChannelIndex > USAC_MAX_NUM_CHANNELS)) { return 1; // invalid arguments error } for (unsigned ch = firstChannelIndex; ch < firstChannelIndex + nChannels; ch++) { const SfbGroupData& grpData = *groupData[ch]; const uint32_t maxSfbInCh = __min (MAX_NUM_SWB_LONG, grpData.sfbsPerGroup); const bool eightShorts = (grpData.numWindowGroups != 1); const bool lowRateTuning = (samplingRate >= 27713) && (sfm[ch] <= (SCHAR_MAX >> 1)); const uint32_t* rms = grpData.sfbRmsValues; uint32_t* stepSizes = &sfbStepSizes[ch * numSwbShort * NUM_WINDOW_GROUPS]; if ((grpData.numWindowGroups * maxSfbInCh == 0) || (grpData.numWindowGroups > NUM_WINDOW_GROUPS)) { continue; } for (unsigned gr = 0; gr < grpData.numWindowGroups; gr++) { const uint16_t* grpOff = &grpData.sfbOffsets[numSwbShort * gr]; const uint8_t* grpSte = (sfbStereoData == nullptr ? nullptr : &sfbStereoData[numSwbShort * gr]); const uint32_t* grpRms = &rms[numSwbShort * gr]; const uint32_t* refRms = &groupData[firstChannelIndex + nChannels - 1 - ch]->sfbRmsValues[numSwbShort * gr]; uint32_t* grpStepSizes = &stepSizes[numSwbShort * gr]; uint32_t b, grpRmsMin = INT_MAX; // min. RMS value, used for overcoding reduction uint64_t s = (eightShorts ? (nSamplesInFrame * grpData.windowGroupLength[gr]) >> 1 : nSamplesInFrame << 2); memset (m_tempSfbValue, UCHAR_MAX, maxSfbInCh * sizeof (uint8_t)); if ((m_rateIndex == 0) && lowRateTuning && (maxSfbInCh > 0) && !eightShorts) { uint32_t numRedBands = nSamplesInFrame; // final result lies between 1/4 and 1/2 if ((nChannels == 2) && commonWindow && (grpSte != nullptr)) { for (b = 0; b < maxSfbInCh; b++) if (grpSte[b] == 0) numRedBands += grpOff[b + 1] - grpOff[b]; } b = MAX_NUM_SWB_LONG - ((numRedBands * ((SCHAR_MAX >> 1) + 1 - sfm[ch]) + (1 << 11)) >> 12); while ((b < maxSfbInCh) && (grpRms[b] > grpRms[b - 1])) b++; // start after peak for (b += ((nChannels == 2) && commonWindow ? b & 1 : 0); b < maxSfbInCh; b++) { grpStepSizes[b] = __max (grpStepSizes[b], grpRms[b] >= (UINT_MAX >> 1) ? UINT_MAX : (grpRms[b] + 1) << 1); } } // undercoding reduction for case where large number of coefs is quantized to zero for (b = 0; b < maxSfbInCh; b++) { const uint32_t rmsComp = (grpSte != nullptr && grpSte[b] > 0 ? squareMeanRoot (refRms[b], grpRms[b]) : grpRms[b]); const uint32_t rmsRef9 = (commonWindow ? refRms[b] >> 9 : rmsComp); const uint8_t sfbWidth = grpOff[b + 1] - grpOff[b]; if (redWeight > 0 && !eightShorts && sfbWidth > (samplingRate >= 18783 ? 8 : 12)) // transient SFBs { const uint32_t gains = m_tnsPredictor->calcParCorCoeffs (&mdctSpec[ch][grpOff[b]], sfbWidth, MAX_PREDICTION_ORDER, tempCoeffs) >> 24; m_tempSfbValue[b] = UCHAR_MAX - uint8_t ((512u + gains * gains * redWeight) >> (10 + (sfbWidth > 16 ? 0 : (20 - sfbWidth) >> 2))); if ((b >= 2) && (m_tempSfbValue[b - 1] < m_tempSfbValue[b]) && (m_tempSfbValue[b - 1] < m_tempSfbValue[b - 2])) { m_tempSfbValue[b - 1] = __min (m_tempSfbValue[b], m_tempSfbValue[b - 2]); // remove local peaks } } if (grpRms[b] < grpRmsMin) grpRmsMin = grpRms[b]; #if 1 if ((m_rateIndex > 0) || lowRateTuning) #endif if (rmsComp >= rmsRef9 && (rmsComp < (grpStepSizes[b] >> 1))) // zero-quantized { s -= (sfbWidth * redFactor * __min (1u << 11, rmsComp) + (1u << 10)) >> 11; } } if ((samplingRate >= 27713) && (b < maxSfbL16k) && !eightShorts) // zeroed HF data { const uint32_t rmsComp = (grpSte != nullptr && grpSte[b] > 0 ? squareMeanRoot (refRms[b], grpRms[b]) : grpRms[b]); const uint32_t rmsRef9 = (commonWindow ? refRms[b] >> 9 : rmsComp); const uint8_t sfbWidth = grpOff[maxSfbL16k] - grpOff[b]; #if 1 if ((m_rateIndex > 0) || lowRateTuning) #endif if (rmsComp >= rmsRef9) // check only first SFB above max_sfb for simplification { s -= (sfbWidth * redFactor * __min (1u << 11, rmsComp) + (1u << 10)) >> 11; } } s = (eightShorts ? s / ((nSamplesInFrame * grpData.windowGroupLength[gr]) >> 8) : s / (nSamplesInFrame >> 5)); if (redWeight > 0 && !eightShorts) memset (tempCoeffs /*= m_tempSfbValue*/, UCHAR_MAX, MAX_PREDICTION_ORDER * sizeof (short)); for (b = 0; b < maxSfbInCh; b++) // improve step-sizes by limiting and attenuation { grpStepSizes[b] = uint32_t ((__max (grpRmsMin, grpStepSizes[b]) * s * (m_tempSfbValue[b] + 1u) + (1u << 14)) >> 15); if (grpStepSizes[b] <= (grpRms[b] >> 11)) grpStepSizes[b] = __max (BA_EPS, grpRms[b] >> 11); if ((m_rateIndex == 0) && lowRateTuning) // clip near-zero SNRs to a minimum SNR { const uint32_t rms = uint32_t ((grpRms[b] * (8192u - (uint64_t) sfm[ch] * sfm[ch]) + (1u << 12)) >> 13); if ((grpStepSizes[b] > grpRms[b]) && ((grpStepSizes[b] >> 1) <= rms)) grpStepSizes[b] = grpRms[b]; } } } } // for ch return 0; // no error }