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diff --git a/libSBRenc/src/tran_det.cpp b/libSBRenc/src/tran_det.cpp new file mode 100644 index 0000000..b6cde99 --- /dev/null +++ b/libSBRenc/src/tran_det.cpp @@ -0,0 +1,701 @@ + +/* ----------------------------------------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2012 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); +} + |