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Diffstat (limited to 'libSBRenc/src/tran_det.cpp')
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diff --git a/libSBRenc/src/tran_det.cpp b/libSBRenc/src/tran_det.cpp deleted file mode 100644 index 1e0a59f..0000000 --- a/libSBRenc/src/tran_det.cpp +++ /dev/null @@ -1,701 +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 ------------------------------------------------------------------------------------------------------------ */ - -#include "tran_det.h" - -#include "fram_gen.h" -#include "sbr_ram.h" -#include "sbr_misc.h" - -#include "genericStds.h" - -#define NORM_QMF_ENERGY 5.684341886080801486968994140625e-14 /* 2^-44 */ - -/* static FIXP_DBL ABS_THRES = fixMax( FL2FXCONST_DBL(1.28e5 * NORM_QMF_ENERGY), (FIXP_DBL)1) Minimum threshold for detecting changes */ -#define ABS_THRES ((FIXP_DBL)16) - -/******************************************************************************* - Functionname: spectralChange - ******************************************************************************* - \brief Calculates a measure for the spectral change within the frame - - The function says how good it would be to split the frame at the given border - position into 2 envelopes. - - The return value delta_sum is scaled with the factor 1/64 - - \return calculated value -*******************************************************************************/ -static FIXP_DBL spectralChange(FIXP_DBL Energies[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS], - INT *scaleEnergies, - FIXP_DBL EnergyTotal, - INT nSfb, - INT start, - INT border, - INT stop) -{ - INT i,j; - INT len1,len2; - FIXP_DBL delta,tmp0,tmp1,tmp2; - FIXP_DBL accu1,accu2,delta_sum,result; - - FDK_ASSERT(scaleEnergies[0] >= 0); - - /* equal for aac (would be not equal for mp3) */ - len1 = border-start; - len2 = stop-border; - - /* prefer borders near the middle of the frame */ - FIXP_DBL pos_weight; - pos_weight = FL2FXCONST_DBL(0.5f) - (len1*GetInvInt(len1+len2)); - pos_weight = /*FL2FXCONST_DBL(1.0)*/ (FIXP_DBL)MAXVAL_DBL - (fMult(pos_weight, pos_weight)<<2); - - delta_sum = FL2FXCONST_DBL(0.0f); - - /* Sum up energies of all QMF-timeslots for both halfs */ - for (j=0; j<nSfb; j++) { - #define NRG_SCALE 3 - /* init with some energy to prevent division by zero - and to prevent splitting for very low levels */ - accu1 = ((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY*8.0/32))) << fixMin(scaleEnergies[0],25))>>NRG_SCALE; /* complex init for compare with original version */ - accu2 = ((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY*8.0/32))) << fixMin(scaleEnergies[0],25))>>NRG_SCALE; /* can be simplified in dsp implementation */ - - /* Sum up energies in first half */ - for (i=start; i<border; i++) { - accu1 += (Energies[i][j]>>NRG_SCALE); - } - - /* Sum up energies in second half */ - for (i=border; i<stop; i++) { - accu2 += (Energies[i][j]>>NRG_SCALE); - } - - /* Energy change in current band */ - tmp0 = CalcLdData(accu2); - tmp1 = CalcLdData(accu1); - tmp2 = (tmp0 - tmp1 + CalcLdData(len1)-CalcLdData(len2)); - delta = fixp_abs(fMult(tmp2, FL2FXCONST_DBL(0.6931471806f))); - - /* Weighting with amplitude ratio of this band */ - result = (EnergyTotal == FL2FXCONST_DBL(0.0f)) - ? FL2FXCONST_DBL(0.f) - : FDKsbrEnc_LSI_divide_scale_fract( (accu1+accu2), - (EnergyTotal>>NRG_SCALE)+(FIXP_DBL)1, - (FIXP_DBL)MAXVAL_DBL >> fixMin(scaleEnergies[0],(DFRACT_BITS-1)) ); - - delta_sum += (FIXP_DBL)(fMult(sqrtFixp(result), delta)); - } - - return fMult(delta_sum, pos_weight); -} - - -/******************************************************************************* - Functionname: addLowbandEnergies - ******************************************************************************* - \brief Calculates total lowband energy - - The return value nrgTotal is scaled by the factor (1/32.0) - - \return total energy in the lowband -*******************************************************************************/ -static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies, - int *scaleEnergies, - int YBufferWriteOffset, - int nrgSzShift, - int tran_off, - UCHAR *freqBandTable, - int slots) -{ - FIXP_DBL nrgTotal; - FIXP_DBL accu1 = FL2FXCONST_DBL(0.0f); - FIXP_DBL accu2 = FL2FXCONST_DBL(0.0f); - int tran_offdiv2 = tran_off>>nrgSzShift; - int ts,k; - - /* Sum up lowband energy from one frame at offset tran_off */ - for (ts=tran_offdiv2; ts<YBufferWriteOffset; ts++) { - for (k = 0; k < freqBandTable[0]; k++) { - accu1 += Energies[ts][k] >> 6; - } - } - for (; ts<tran_offdiv2+(slots>>nrgSzShift); ts++) { - for (k = 0; k < freqBandTable[0]; k++) { - accu2 += Energies[ts][k] >> 6; - } - } - - nrgTotal = ( (accu1 >> fixMin(scaleEnergies[0],(DFRACT_BITS-1))) - + (accu2 >> fixMin(scaleEnergies[1],(DFRACT_BITS-1))) ) << (2); - - return(nrgTotal); -} - - -/******************************************************************************* - Functionname: addHighbandEnergies - ******************************************************************************* - \brief Add highband energies - - Highband energies are mapped to an array with smaller dimension: - Its time resolution is only 1 SBR-timeslot and its frequency resolution - is 1 SBR-band. Therefore the data to be fed into the spectralChange - function is reduced. - - The values EnergiesM are scaled by the factor (1/32.0) and scaleEnergies[0] - The return value nrgTotal is scaled by the factor (1/32.0) - - \return total energy in the highband -*******************************************************************************/ - -static FIXP_DBL addHighbandEnergies(FIXP_DBL **RESTRICT Energies, /*!< input */ - INT *scaleEnergies, - FIXP_DBL EnergiesM[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS], /*!< Combined output */ - UCHAR *RESTRICT freqBandTable, - INT nSfb, - INT sbrSlots, - INT timeStep) -{ - INT i,j,k,slotIn,slotOut,scale; - INT li,ui; - FIXP_DBL nrgTotal; - FIXP_DBL accu = FL2FXCONST_DBL(0.0f); - - /* Combine QMF-timeslots to SBR-timeslots, - combine QMF-bands to SBR-bands, - combine Left and Right channel */ - for (slotOut=0; slotOut<sbrSlots; slotOut++) { - slotIn = 2*slotOut; - - for (j=0; j<nSfb; j++) { - accu = FL2FXCONST_DBL(0.0f); - - li = freqBandTable[j]; - ui = freqBandTable[j + 1]; - - for (k=li; k<ui; k++) { - for (i=0; i<timeStep; i++) { - accu += (Energies[(slotIn+i)>>1][k] >> 5); - } - } - EnergiesM[slotOut][j] = accu; - } - } - - scale = fixMin(8,scaleEnergies[0]); /* scale energies down before add up */ - - if ((scaleEnergies[0]-1) > (DFRACT_BITS-1) ) - nrgTotal = FL2FXCONST_DBL(0.0f); - else { - /* Now add all energies */ - accu = FL2FXCONST_DBL(0.0f); - for (slotOut=0; slotOut<sbrSlots; slotOut++) { - for (j=0; j<nSfb; j++) { - accu += (EnergiesM[slotOut][j] >> scale); - } - } - nrgTotal = accu >> (scaleEnergies[0]-scale); - } - - return(nrgTotal); -} - - -/******************************************************************************* - Functionname: FDKsbrEnc_frameSplitter - ******************************************************************************* - \brief Decides if a FIXFIX-frame shall be splitted into 2 envelopes - - If no transient has been detected before, the frame can still be splitted - into 2 envelopes. -*******************************************************************************/ -void -FDKsbrEnc_frameSplitter(FIXP_DBL **Energies, - INT *scaleEnergies, - HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector, - UCHAR *freqBandTable, - UCHAR *tran_vector, - int YBufferWriteOffset, - int YBufferSzShift, - int nSfb, - int timeStep, - int no_cols) -{ - if (tran_vector[1]==0) /* no transient was detected */ - { - FIXP_DBL delta; - FIXP_DBL EnergiesM[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS]; - FIXP_DBL EnergyTotal,newLowbandEnergy,newHighbandEnergy; - INT border; - INT sbrSlots = fMultI(GetInvInt(timeStep),no_cols); - - FDK_ASSERT( sbrSlots * timeStep == no_cols ); - - /* - Get Lowband-energy over a range of 2 frames (Look half a frame back and ahead). - */ - newLowbandEnergy = addLowbandEnergies(Energies, - scaleEnergies, - YBufferWriteOffset, - YBufferSzShift, - h_sbrTransientDetector->tran_off, - freqBandTable, - no_cols); - - newHighbandEnergy = addHighbandEnergies(Energies, - scaleEnergies, - EnergiesM, - freqBandTable, - nSfb, - sbrSlots, - timeStep); - - if ( h_sbrTransientDetector->frameShift != 0 ) { - if (tran_vector[1]==0) - tran_vector[0] = 0; - } else - { - /* prevLowBandEnergy: Corresponds to 1 frame, starting with half a frame look-behind - newLowbandEnergy: Corresponds to 1 frame, starting in the middle of the current frame */ - EnergyTotal = (newLowbandEnergy + h_sbrTransientDetector->prevLowBandEnergy) >> 1; - EnergyTotal += newHighbandEnergy; - /* The below border should specify the same position as the middle border - of a FIXFIX-frame with 2 envelopes. */ - border = (sbrSlots+1) >> 1; - - delta = spectralChange(EnergiesM, - scaleEnergies, - EnergyTotal, - nSfb, - 0, - border, - sbrSlots); - - if (delta > (h_sbrTransientDetector->split_thr >> LD_DATA_SHIFT)) /* delta scaled by 1/64 */ - tran_vector[0] = 1; /* Set flag for splitting */ - else - tran_vector[0] = 0; - } - - /* Update prevLowBandEnergy */ - h_sbrTransientDetector->prevLowBandEnergy = newLowbandEnergy; - h_sbrTransientDetector->prevHighBandEnergy = newHighbandEnergy; - } -} - -/* - * Calculate transient energy threshold for each QMF band - */ -static void -calculateThresholds(FIXP_DBL **RESTRICT Energies, - INT *RESTRICT scaleEnergies, - FIXP_DBL *RESTRICT thresholds, - int YBufferWriteOffset, - int YBufferSzShift, - int noCols, - int noRows, - int tran_off) -{ - FIXP_DBL mean_val,std_val,temp; - FIXP_DBL i_noCols; - FIXP_DBL i_noCols1; - FIXP_DBL accu,accu0,accu1; - int scaleFactor0,scaleFactor1,commonScale; - int i,j; - - i_noCols = GetInvInt(noCols + tran_off ) << YBufferSzShift; - i_noCols1 = GetInvInt(noCols + tran_off - 1) << YBufferSzShift; - - /* calc minimum scale of energies of previous and current frame */ - commonScale = fixMin(scaleEnergies[0],scaleEnergies[1]); - - /* calc scalefactors to adapt energies to common scale */ - scaleFactor0 = fixMin((scaleEnergies[0]-commonScale), (DFRACT_BITS-1)); - scaleFactor1 = fixMin((scaleEnergies[1]-commonScale), (DFRACT_BITS-1)); - - FDK_ASSERT((scaleFactor0 >= 0) && (scaleFactor1 >= 0)); - - /* calculate standard deviation in every subband */ - for (i=0; i<noRows; i++) - { - int startEnergy = (tran_off>>YBufferSzShift); - int endEnergy = ((noCols>>YBufferSzShift)+tran_off); - int shift; - - /* calculate mean value over decimated energy values (downsampled by 2). */ - accu0 = accu1 = FL2FXCONST_DBL(0.0f); - - for (j=startEnergy; j<YBufferWriteOffset; j++) - accu0 += fMult(Energies[j][i], i_noCols); - for (; j<endEnergy; j++) - accu1 += fMult(Energies[j][i], i_noCols); - - mean_val = (accu0 >> scaleFactor0) + (accu1 >> scaleFactor1); /* average */ - shift = fixMax(0,CountLeadingBits(mean_val)-6); /* -6 to keep room for accumulating upto N = 24 values */ - - /* calculate standard deviation */ - accu = FL2FXCONST_DBL(0.0f); - - /* summe { ((mean_val-nrg)^2) * i_noCols1 } */ - for (j=startEnergy; j<YBufferWriteOffset; j++) { - temp = ((FIXP_DBL)mean_val - ((FIXP_DBL)Energies[j][i] >> scaleFactor0))<<shift; - temp = fPow2(temp); - temp = fMult(temp, i_noCols1); - accu += temp; - } - for (; j<endEnergy; j++) { - temp = ((FIXP_DBL)mean_val - ((FIXP_DBL)Energies[j][i] >> scaleFactor1))<<shift; - temp = fPow2(temp); - temp = fMult(temp, i_noCols1); - accu += temp; - } - - std_val = sqrtFixp(accu)>>shift; /* standard deviation */ - - /* - Take new threshold as average of calculated standard deviation ratio - and old threshold if greater than absolute threshold - */ - temp = ( commonScale<=(DFRACT_BITS-1) ) - ? fMult(FL2FXCONST_DBL(0.66f), thresholds[i]) + (fMult(FL2FXCONST_DBL(0.34f), std_val) >> commonScale) - : (FIXP_DBL) 0; - - thresholds[i] = fixMax(ABS_THRES,temp); - - FDK_ASSERT(commonScale >= 0); - } -} - -/* - * Calculate transient levels for each QMF time slot. - */ -static void -extractTransientCandidates(FIXP_DBL **RESTRICT Energies, - INT *RESTRICT scaleEnergies, - FIXP_DBL *RESTRICT thresholds, - FIXP_DBL *RESTRICT transients, - int YBufferWriteOffset, - int YBufferSzShift, - int noCols, - int start_band, - int stop_band, - int tran_off, - int addPrevSamples) -{ - FIXP_DBL i_thres; - C_ALLOC_SCRATCH_START(EnergiesTemp, FIXP_DBL, 2*QMF_MAX_TIME_SLOTS); - FIXP_DBL *RESTRICT pEnergiesTemp = EnergiesTemp; - int tmpScaleEnergies0, tmpScaleEnergies1; - int endCond; - int startEnerg,endEnerg; - int i,j,jIndex,jpBM; - - tmpScaleEnergies0 = scaleEnergies[0]; - tmpScaleEnergies1 = scaleEnergies[1]; - - /* Scale value for first energies, upto YBufferWriteOffset */ - tmpScaleEnergies0 = fixMin(tmpScaleEnergies0, MAX_SHIFT_DBL); - /* Scale value for first energies, from YBufferWriteOffset upwards */ - tmpScaleEnergies1 = fixMin(tmpScaleEnergies1, MAX_SHIFT_DBL); - - FDK_ASSERT((tmpScaleEnergies0 >= 0) && (tmpScaleEnergies1 >= 0)); - - /* Keep addPrevSamples extra previous transient candidates. */ - FDKmemmove(transients, transients + noCols - addPrevSamples, (tran_off+addPrevSamples) * sizeof (FIXP_DBL)); - FDKmemclear(transients + tran_off + addPrevSamples, noCols * sizeof (FIXP_DBL)); - - endCond = noCols; /* Amount of new transient values to be calculated. */ - startEnerg = (tran_off-3)>>YBufferSzShift; /* >>YBufferSzShift because of amount of energy values. -3 because of neighbors being watched. */ - endEnerg = ((noCols+ (YBufferWriteOffset<<YBufferSzShift))-1)>>YBufferSzShift; /* YBufferSzShift shifts because of half energy values. */ - - /* Compute differential values with two different weightings in every subband */ - for (i=start_band; i<stop_band; i++) - { - FIXP_DBL thres = thresholds[i]; - - if((LONG)thresholds[i]>=256) - i_thres = (LONG)( (LONG)MAXVAL_DBL / ((((LONG)thresholds[i]))+1) )<<(32-24); - else - i_thres = (LONG)MAXVAL_DBL; - - /* Copy one timeslot and de-scale and de-squish */ - if (YBufferSzShift == 1) { - for(j=startEnerg; j<YBufferWriteOffset; j++) { - FIXP_DBL tmp = Energies[j][i]; - EnergiesTemp[(j<<1)+1] = EnergiesTemp[j<<1] = tmp>>tmpScaleEnergies0; - } - for(; j<=endEnerg; j++) { - FIXP_DBL tmp = Energies[j][i]; - EnergiesTemp[(j<<1)+1] = EnergiesTemp[j<<1] = tmp>>tmpScaleEnergies1; - } - } else { - for(j=startEnerg; j<YBufferWriteOffset; j++) { - FIXP_DBL tmp = Energies[j][i]; - EnergiesTemp[j] = tmp>>tmpScaleEnergies0; - } - for(; j<=endEnerg; j++) { - FIXP_DBL tmp = Energies[j][i]; - EnergiesTemp[j] = tmp>>tmpScaleEnergies1; - } - } - - /* Detect peaks in energy values. */ - - jIndex = tran_off; - jpBM = jIndex+addPrevSamples; - - for (j=endCond; j--; jIndex++, jpBM++) - { - - FIXP_DBL delta, tran; - int d; - - delta = (FIXP_DBL)0; - tran = (FIXP_DBL)0; - - for (d=1; d<4; d++) { - delta += pEnergiesTemp[jIndex+d]; /* R */ - delta -= pEnergiesTemp[jIndex-d]; /* L */ - delta -= thres; - - if ( delta > (FIXP_DBL)0 ) { - tran += fMult(i_thres, delta); - } - } - transients[jpBM] += tran; - } - } - C_ALLOC_SCRATCH_END(EnergiesTemp, FIXP_DBL, 2*QMF_MAX_TIME_SLOTS); -} - -void -FDKsbrEnc_transientDetect(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTran, - FIXP_DBL **Energies, - INT *scaleEnergies, - UCHAR *transient_info, - int YBufferWriteOffset, - int YBufferSzShift, - int timeStep, - int frameMiddleBorder) -{ - int no_cols = h_sbrTran->no_cols; - int qmfStartSample; - int addPrevSamples; - int timeStepShift=0; - int i, cond; - - /* Where to start looking for transients in the transient candidate buffer */ - qmfStartSample = timeStep * frameMiddleBorder; - /* We need to look one value backwards in the transients, so we might need one more previous value. */ - addPrevSamples = (qmfStartSample > 0) ? 0: 1; - - switch (timeStep) { - case 1: timeStepShift = 0; break; - case 2: timeStepShift = 1; break; - case 4: timeStepShift = 2; break; - } - - calculateThresholds(Energies, - scaleEnergies, - h_sbrTran->thresholds, - YBufferWriteOffset, - YBufferSzShift, - h_sbrTran->no_cols, - h_sbrTran->no_rows, - h_sbrTran->tran_off); - - extractTransientCandidates(Energies, - scaleEnergies, - h_sbrTran->thresholds, - h_sbrTran->transients, - YBufferWriteOffset, - YBufferSzShift, - h_sbrTran->no_cols, - 0, - h_sbrTran->no_rows, - h_sbrTran->tran_off, - addPrevSamples ); - - transient_info[0] = 0; - transient_info[1] = 0; - transient_info[2] = 0; - - /* Offset by the amount of additional previous transient candidates being kept. */ - qmfStartSample += addPrevSamples; - - /* Check for transients in second granule (pick the last value of subsequent values) */ - for (i=qmfStartSample; i<qmfStartSample + no_cols; i++) { - cond = (h_sbrTran->transients[i] < fMult(FL2FXCONST_DBL(0.9f), h_sbrTran->transients[i - 1]) ) - && (h_sbrTran->transients[i - 1] > h_sbrTran->tran_thr); - - if (cond) { - transient_info[0] = (i - qmfStartSample)>>timeStepShift; - transient_info[1] = 1; - break; - } - } - - if ( h_sbrTran->frameShift != 0) { - /* transient prediction for LDSBR */ - /* Check for transients in first <frameShift> qmf-slots of second frame */ - for (i=qmfStartSample+no_cols; i<qmfStartSample + no_cols+h_sbrTran->frameShift; i++) { - - cond = (h_sbrTran->transients[i] < fMult(FL2FXCONST_DBL(0.9f), h_sbrTran->transients[i - 1]) ) - && (h_sbrTran->transients[i - 1] > h_sbrTran->tran_thr); - - if (cond) { - int pos = (int) ( (i - qmfStartSample-no_cols) >> timeStepShift ); - if ((pos < 3) && (transient_info[1]==0)) { - transient_info[2] = 1; - } - break; - } - } - } -} - -int -FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector, - INT frameSize, - INT sampleFreq, - sbrConfigurationPtr params, - int tran_fc, - int no_cols, - int no_rows, - int YBufferWriteOffset, - int YBufferSzShift, - int frameShift, - int tran_off) -{ - INT totalBitrate = params->codecSettings.standardBitrate * params->codecSettings.nChannels; - INT codecBitrate = params->codecSettings.bitRate; - FIXP_DBL bitrateFactor_fix, framedur_fix; - INT scale_0, scale_1; - - FDKmemclear(h_sbrTransientDetector,sizeof(SBR_TRANSIENT_DETECTOR)); - - h_sbrTransientDetector->frameShift = frameShift; - h_sbrTransientDetector->tran_off = tran_off; - - if(codecBitrate) { - bitrateFactor_fix = fDivNorm((FIXP_DBL)totalBitrate, (FIXP_DBL)(codecBitrate<<2),&scale_0); - } - else { - bitrateFactor_fix = FL2FXCONST_DBL(1.0/4.0); - scale_0 = 0; - } - - framedur_fix = fDivNorm(frameSize, sampleFreq); - - /* The longer the frames, the more often should the FIXFIX- - case transmit 2 envelopes instead of 1. - Frame durations below 10 ms produce the highest threshold - so that practically always only 1 env is transmitted. */ - FIXP_DBL tmp = framedur_fix - FL2FXCONST_DBL(0.010); - - tmp = fixMax(tmp, FL2FXCONST_DBL(0.0001)); - tmp = fDivNorm(FL2FXCONST_DBL(0.000075), fPow2(tmp), &scale_1); - - scale_1 = -(scale_1 + scale_0 + 2); - - FDK_ASSERT(no_cols <= QMF_MAX_TIME_SLOTS); - FDK_ASSERT(no_rows <= QMF_CHANNELS); - - h_sbrTransientDetector->no_cols = no_cols; - h_sbrTransientDetector->tran_thr = (FIXP_DBL)((params->tran_thr << (32-24-1)) / no_rows); - h_sbrTransientDetector->tran_fc = tran_fc; - - if (scale_1>=0) { - h_sbrTransientDetector->split_thr = fMult(tmp, bitrateFactor_fix) >> scale_1; - } - else { - h_sbrTransientDetector->split_thr = fMult(tmp, bitrateFactor_fix) << (-scale_1); - } - - h_sbrTransientDetector->no_rows = no_rows; - h_sbrTransientDetector->mode = params->tran_det_mode; - h_sbrTransientDetector->prevLowBandEnergy = FL2FXCONST_DBL(0.0f); - - return (0); -} - |