void WebRtcVad_LogOfEnergy(WebRtc_Word16 *vector,
WebRtc_Word16 *enerlogval,
WebRtc_Word16 *power,
WebRtc_Word16 offset,
int vector_length)
{
WebRtc_Word16 enerSum = 0;
WebRtc_Word16 zeros, frac, log2;
WebRtc_Word32 energy;
int shfts = 0, shfts2;
energy = WebRtcSpl_Energy(vector, vector_length, &shfts);
if (energy > 0)
{
shfts2 = 16 - WebRtcSpl_NormW32(energy);
shfts += shfts2;
// "shfts" is the total number of right shifts that has been done to enerSum.
enerSum = (WebRtc_Word16)WEBRTC_SPL_SHIFT_W32(energy, -shfts2);
// Find:
// 160*log10(enerSum*2^shfts) = 160*log10(2)*log2(enerSum*2^shfts) =
// 160*log10(2)*(log2(enerSum) + log2(2^shfts)) =
// 160*log10(2)*(log2(enerSum) + shfts)
zeros = WebRtcSpl_NormU32(enerSum);
frac = (WebRtc_Word16)(((WebRtc_UWord32)((WebRtc_Word32)(enerSum) << zeros)
& 0x7FFFFFFF) >> 21);
log2 = (WebRtc_Word16)(((31 - zeros) << 10) + frac);
*enerlogval = (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(kLogConst, log2, 19)
+ (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(shfts, kLogConst, 9);
if (*enerlogval < 0)
{
*enerlogval = 0;
}
} else
int WebRtcIlbcfix_XcorrCoef(
WebRtc_Word16 *target, /* (i) first array */
WebRtc_Word16 *regressor, /* (i) second array */
WebRtc_Word16 subl, /* (i) dimension arrays */
WebRtc_Word16 searchLen, /* (i) the search lenght */
WebRtc_Word16 offset, /* (i) samples offset between arrays */
WebRtc_Word16 step /* (i) +1 or -1 */
){
int k;
WebRtc_Word16 maxlag;
WebRtc_Word16 pos;
WebRtc_Word16 max;
WebRtc_Word16 crossCorrScale, Energyscale;
WebRtc_Word16 crossCorrSqMod, crossCorrSqMod_Max;
WebRtc_Word32 crossCorr, Energy;
WebRtc_Word16 crossCorrmod, EnergyMod, EnergyMod_Max;
WebRtc_Word16 *tp, *rp;
WebRtc_Word16 *rp_beg, *rp_end;
WebRtc_Word16 totscale, totscale_max;
WebRtc_Word16 scalediff;
WebRtc_Word32 newCrit, maxCrit;
int shifts;
/* Initializations, to make sure that the first one is selected */
crossCorrSqMod_Max=0;
EnergyMod_Max=WEBRTC_SPL_WORD16_MAX;
totscale_max=-500;
maxlag=0;
pos=0;
/* Find scale value and start position */
if (step==1) {
max=WebRtcSpl_MaxAbsValueW16(regressor, (WebRtc_Word16)(subl+searchLen-1));
rp_beg = regressor;
rp_end = ®ressor[subl];
} else { /* step==-1 */
max=WebRtcSpl_MaxAbsValueW16(®ressor[-searchLen], (WebRtc_Word16)(subl+searchLen-1));
rp_beg = ®ressor[-1];
rp_end = ®ressor[subl-1];
}
/* Introduce a scale factor on the Energy in WebRtc_Word32 in
order to make sure that the calculation does not
overflow */
if (max>5000) {
shifts=2;
} else {
shifts=0;
}
/* Calculate the first energy, then do a +/- to get the other energies */
Energy=WebRtcSpl_DotProductWithScale(regressor, regressor, subl, shifts);
for (k=0;k<searchLen;k++) {
tp = target;
rp = ®ressor[pos];
crossCorr=WebRtcSpl_DotProductWithScale(tp, rp, subl, shifts);
if ((Energy>0)&&(crossCorr>0)) {
/* Put cross correlation and energy on 16 bit word */
crossCorrScale=(WebRtc_Word16)WebRtcSpl_NormW32(crossCorr)-16;
crossCorrmod=(WebRtc_Word16)WEBRTC_SPL_SHIFT_W32(crossCorr, crossCorrScale);
Energyscale=(WebRtc_Word16)WebRtcSpl_NormW32(Energy)-16;
EnergyMod=(WebRtc_Word16)WEBRTC_SPL_SHIFT_W32(Energy, Energyscale);
/* Square cross correlation and store upper WebRtc_Word16 */
crossCorrSqMod=(WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(crossCorrmod, crossCorrmod, 16);
/* Calculate the total number of (dynamic) right shifts that have
been performed on (crossCorr*crossCorr)/energy
*/
totscale=Energyscale-(crossCorrScale<<1);
/* Calculate the shift difference in order to be able to compare the two
(crossCorr*crossCorr)/energy in the same domain
*/
scalediff=totscale-totscale_max;
scalediff=WEBRTC_SPL_MIN(scalediff,31);
scalediff=WEBRTC_SPL_MAX(scalediff,-31);
/* Compute the cross multiplication between the old best criteria
and the new one to be able to compare them without using a
division */
if (scalediff<0) {
newCrit = ((WebRtc_Word32)crossCorrSqMod*EnergyMod_Max)>>(-scalediff);
maxCrit = ((WebRtc_Word32)crossCorrSqMod_Max*EnergyMod);
} else {
void WebRtcIlbcfix_CbSearch(
IlbcEncoder *iLBCenc_inst,
/* (i) the encoder state structure */
int16_t *index, /* (o) Codebook indices */
int16_t *gain_index, /* (o) Gain quantization indices */
int16_t *intarget, /* (i) Target vector for encoding */
int16_t *decResidual,/* (i) Decoded residual for codebook construction */
int16_t lMem, /* (i) Length of buffer */
int16_t lTarget, /* (i) Length of vector */
int16_t *weightDenum,/* (i) weighting filter coefficients in Q12 */
int16_t block /* (i) the subblock number */
) {
int16_t i, j, stage, range;
int16_t *pp, scale, tmp;
int16_t bits, temp1, temp2;
int16_t base_size;
int32_t codedEner, targetEner;
int16_t gains[CB_NSTAGES+1];
int16_t *cb_vecPtr;
int16_t indexOffset, sInd, eInd;
int32_t CritMax=0;
int16_t shTotMax=WEBRTC_SPL_WORD16_MIN;
int16_t bestIndex=0;
int16_t bestGain=0;
int16_t indexNew, CritNewSh;
int32_t CritNew;
int32_t *cDotPtr;
int16_t noOfZeros;
int16_t *gainPtr;
int32_t t32, tmpW32;
int16_t *WebRtcIlbcfix_kGainSq5_ptr;
/* Stack based */
int16_t CBbuf[CB_MEML+LPC_FILTERORDER+CB_HALFFILTERLEN];
int32_t cDot[128];
int32_t Crit[128];
int16_t targetVec[SUBL+LPC_FILTERORDER];
int16_t cbvectors[CB_MEML + 1]; /* Adding one extra position for
Coverity warnings. */
int16_t codedVec[SUBL];
int16_t interpSamples[20*4];
int16_t interpSamplesFilt[20*4];
int16_t energyW16[CB_EXPAND*128];
int16_t energyShifts[CB_EXPAND*128];
int16_t *inverseEnergy=energyW16; /* Reuse memory */
int16_t *inverseEnergyShifts=energyShifts; /* Reuse memory */
int16_t *buf = &CBbuf[LPC_FILTERORDER];
int16_t *target = &targetVec[LPC_FILTERORDER];
int16_t *aug_vec = (int16_t*)cDot; /* length [SUBL], reuse memory */
/* Determine size of codebook sections */
base_size=lMem-lTarget+1;
if (lTarget==SUBL) {
base_size=lMem-19;
}
/* weighting of the CB memory */
noOfZeros=lMem-WebRtcIlbcfix_kFilterRange[block];
WebRtcSpl_MemSetW16(&buf[-LPC_FILTERORDER], 0, noOfZeros+LPC_FILTERORDER);
WebRtcSpl_FilterARFastQ12(
decResidual+noOfZeros, buf+noOfZeros,
weightDenum, LPC_FILTERORDER+1, WebRtcIlbcfix_kFilterRange[block]);
/* weighting of the target vector */
WEBRTC_SPL_MEMCPY_W16(&target[-LPC_FILTERORDER], buf+noOfZeros+WebRtcIlbcfix_kFilterRange[block]-LPC_FILTERORDER, LPC_FILTERORDER);
WebRtcSpl_FilterARFastQ12(
intarget, target,
weightDenum, LPC_FILTERORDER+1, lTarget);
/* Store target, towards the end codedVec is calculated as
the initial target minus the remaining target */
WEBRTC_SPL_MEMCPY_W16(codedVec, target, lTarget);
/* Find the highest absolute value to calculate proper
vector scale factor (so that it uses 12 bits) */
temp1 = WebRtcSpl_MaxAbsValueW16(buf, (int16_t)lMem);
temp2 = WebRtcSpl_MaxAbsValueW16(target, (int16_t)lTarget);
if ((temp1>0)&&(temp2>0)) {
temp1 = WEBRTC_SPL_MAX(temp1, temp2);
scale = WebRtcSpl_GetSizeInBits(WEBRTC_SPL_MUL_16_16(temp1, temp1));
} else {
/* temp1 or temp2 is negative (maximum was -32768) */
scale = 30;
}
/* Scale to so that a mul-add 40 times does not overflow */
scale = scale - 25;
scale = WEBRTC_SPL_MAX(0, scale);
/* Compute energy of the original target */
targetEner = WebRtcSpl_DotProductWithScale(target, target, lTarget, scale);
/* Prepare search over one more codebook section. This section
is created by filtering the original buffer with a filter. */
WebRtcIlbcfix_FilteredCbVecs(cbvectors, buf, lMem, WebRtcIlbcfix_kFilterRange[block]);
range = WebRtcIlbcfix_kSearchRange[block][0];
if(lTarget == SUBL) {
/* Create the interpolated samples and store them for use in all stages */
/* First section, non-filtered half of the cb */
WebRtcIlbcfix_InterpolateSamples(interpSamples, buf, lMem);
/* Second section, filtered half of the cb */
WebRtcIlbcfix_InterpolateSamples(interpSamplesFilt, cbvectors, lMem);
/* Compute the CB vectors' energies for the first cb section (non-filtered) */
WebRtcIlbcfix_CbMemEnergyAugmentation(interpSamples, buf,
scale, 20, energyW16, energyShifts);
/* Compute the CB vectors' energies for the second cb section (filtered cb) */
WebRtcIlbcfix_CbMemEnergyAugmentation(interpSamplesFilt, cbvectors,
scale, (int16_t)(base_size+20), energyW16, energyShifts);
/* Compute the CB vectors' energies and store them in the vector
* energyW16. Also the corresponding shift values are stored. The
* energy values are used in all three stages. */
WebRtcIlbcfix_CbMemEnergy(range, buf, cbvectors, lMem,
lTarget, energyW16+20, energyShifts+20, scale, base_size);
} else {
/* Compute the CB vectors' energies and store them in the vector
* energyW16. Also the corresponding shift values are stored. The
* energy values are used in all three stages. */
WebRtcIlbcfix_CbMemEnergy(range, buf, cbvectors, lMem,
lTarget, energyW16, energyShifts, scale, base_size);
/* Set the energy positions 58-63 and 122-127 to zero
(otherwise they are uninitialized) */
WebRtcSpl_MemSetW16(energyW16+range, 0, (base_size-range));
WebRtcSpl_MemSetW16(energyW16+range+base_size, 0, (base_size-range));
}
/* Calculate Inverse Energy (energyW16 is already normalized
and will contain the inverse energy in Q29 after this call */
WebRtcIlbcfix_EnergyInverse(energyW16, base_size*CB_EXPAND);
/* The gain value computed in the previous stage is used
* as an upper limit to what the next stage gain value
* is allowed to be. In stage 0, 16384 (1.0 in Q14) is used as
* the upper limit. */
gains[0] = 16384;
for (stage=0; stage<CB_NSTAGES; stage++) {
/* Set up memories */
range = WebRtcIlbcfix_kSearchRange[block][stage];
/* initialize search measures */
CritMax=0;
shTotMax=-100;
bestIndex=0;
bestGain=0;
/* loop over lags 40+ in the first codebook section, full search */
cb_vecPtr = buf+lMem-lTarget;
/* Calculate all the cross correlations (augmented part of CB) */
if (lTarget==SUBL) {
WebRtcIlbcfix_AugmentedCbCorr(target, buf+lMem,
interpSamples, cDot,
20, 39, scale);
cDotPtr=&cDot[20];
} else {
cDotPtr=cDot;
}
/* Calculate all the cross correlations (main part of CB) */
WebRtcSpl_CrossCorrelation(cDotPtr, target, cb_vecPtr, lTarget, range, scale, -1);
/* Adjust the search range for the augmented vectors */
if (lTarget==SUBL) {
range=WebRtcIlbcfix_kSearchRange[block][stage]+20;
} else {
range=WebRtcIlbcfix_kSearchRange[block][stage];
}
indexOffset=0;
/* Search for best index in this part of the vector */
WebRtcIlbcfix_CbSearchCore(
cDot, range, stage, inverseEnergy,
inverseEnergyShifts, Crit,
&indexNew, &CritNew, &CritNewSh);
/* Update the global best index and the corresponding gain */
WebRtcIlbcfix_CbUpdateBestIndex(
CritNew, CritNewSh, (int16_t)(indexNew+indexOffset), cDot[indexNew+indexOffset],
inverseEnergy[indexNew+indexOffset], inverseEnergyShifts[indexNew+indexOffset],
&CritMax, &shTotMax, &bestIndex, &bestGain);
sInd=bestIndex-(int16_t)(CB_RESRANGE>>1);
eInd=sInd+CB_RESRANGE;
if (sInd<0) {
eInd-=sInd;
sInd=0;
}
if (eInd>=range) {
eInd=range-1;
sInd=eInd-CB_RESRANGE;
}
range = WebRtcIlbcfix_kSearchRange[block][stage];
if (lTarget==SUBL) {
i=sInd;
if (sInd<20) {
WebRtcIlbcfix_AugmentedCbCorr(target, cbvectors+lMem,
interpSamplesFilt, cDot,
(int16_t)(sInd+20), (int16_t)(WEBRTC_SPL_MIN(39, (eInd+20))), scale);
i=20;
}
cDotPtr=&cDot[WEBRTC_SPL_MAX(0,(20-sInd))];
cb_vecPtr = cbvectors+lMem-20-i;
/* Calculate the cross correlations (main part of the filtered CB) */
WebRtcSpl_CrossCorrelation(cDotPtr, target, cb_vecPtr, lTarget, (int16_t)(eInd-i+1), scale, -1);
} else {
cDotPtr = cDot;
cb_vecPtr = cbvectors+lMem-lTarget-sInd;
/* Calculate the cross correlations (main part of the filtered CB) */
WebRtcSpl_CrossCorrelation(cDotPtr, target, cb_vecPtr, lTarget, (int16_t)(eInd-sInd+1), scale, -1);
}
/* Adjust the search range for the augmented vectors */
indexOffset=base_size+sInd;
/* Search for best index in this part of the vector */
WebRtcIlbcfix_CbSearchCore(
cDot, (int16_t)(eInd-sInd+1), stage, inverseEnergy+indexOffset,
inverseEnergyShifts+indexOffset, Crit,
&indexNew, &CritNew, &CritNewSh);
/* Update the global best index and the corresponding gain */
WebRtcIlbcfix_CbUpdateBestIndex(
CritNew, CritNewSh, (int16_t)(indexNew+indexOffset), cDot[indexNew],
inverseEnergy[indexNew+indexOffset], inverseEnergyShifts[indexNew+indexOffset],
&CritMax, &shTotMax, &bestIndex, &bestGain);
index[stage] = bestIndex;
bestGain = WebRtcIlbcfix_GainQuant(bestGain,
(int16_t)WEBRTC_SPL_ABS_W16(gains[stage]), stage, &gain_index[stage]);
/* Extract the best (according to measure) codebook vector
Also adjust the index, so that the augmented vectors are last.
Above these vectors were first...
*/
if(lTarget==(STATE_LEN-iLBCenc_inst->state_short_len)) {
if(index[stage]<base_size) {
pp=buf+lMem-lTarget-index[stage];
} else {
pp=cbvectors+lMem-lTarget-
index[stage]+base_size;
}
} else {
if (index[stage]<base_size) {
if (index[stage]>=20) {
/* Adjust index and extract vector */
index[stage]-=20;
pp=buf+lMem-lTarget-index[stage];
} else {
/* Adjust index and extract vector */
index[stage]+=(base_size-20);
WebRtcIlbcfix_CreateAugmentedVec((int16_t)(index[stage]-base_size+40),
buf+lMem, aug_vec);
pp = aug_vec;
}
} else {
if ((index[stage] - base_size) >= 20) {
/* Adjust index and extract vector */
index[stage]-=20;
pp=cbvectors+lMem-lTarget-
index[stage]+base_size;
} else {
/* Adjust index and extract vector */
index[stage]+=(base_size-20);
WebRtcIlbcfix_CreateAugmentedVec((int16_t)(index[stage]-2*base_size+40),
cbvectors+lMem, aug_vec);
pp = aug_vec;
}
}
}
/* Subtract the best codebook vector, according
to measure, from the target vector */
WebRtcSpl_AddAffineVectorToVector(target, pp, (int16_t)(-bestGain), (int32_t)8192, (int16_t)14, (int)lTarget);
/* record quantized gain */
gains[stage+1] = bestGain;
} /* end of Main Loop. for (stage=0;... */
/* Calculte the coded vector (original target - what's left) */
for (i=0;i<lTarget;i++) {
codedVec[i]-=target[i];
}
/* Gain adjustment for energy matching */
codedEner = WebRtcSpl_DotProductWithScale(codedVec, codedVec, lTarget, scale);
j=gain_index[0];
temp1 = (int16_t)WebRtcSpl_NormW32(codedEner);
temp2 = (int16_t)WebRtcSpl_NormW32(targetEner);
if(temp1 < temp2) {
bits = 16 - temp1;
} else {
bits = 16 - temp2;
}
tmp = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(gains[1],gains[1], 14);
targetEner = WEBRTC_SPL_MUL_16_16(
WEBRTC_SPL_SHIFT_W32(targetEner, -bits), tmp);
tmpW32 = ((int32_t)(gains[1]-1))<<1;
/* Pointer to the table that contains
gain_sq5TblFIX * gain_sq5TblFIX in Q14 */
gainPtr=(int16_t*)WebRtcIlbcfix_kGainSq5Sq+gain_index[0];
temp1 = (int16_t)WEBRTC_SPL_SHIFT_W32(codedEner, -bits);
WebRtcIlbcfix_kGainSq5_ptr = (int16_t*)&WebRtcIlbcfix_kGainSq5[j];
/* targetEner and codedEner are in Q(-2*scale) */
for (i=gain_index[0];i<32;i++) {
/* Change the index if
(codedEnergy*gainTbl[i]*gainTbl[i])<(targetEn*gain[0]*gain[0]) AND
gainTbl[i] < 2*gain[0]
*/
t32 = WEBRTC_SPL_MUL_16_16(temp1, (*gainPtr));
t32 = t32 - targetEner;
if (t32 < 0) {
if ((*WebRtcIlbcfix_kGainSq5_ptr) < tmpW32) {
j=i;
WebRtcIlbcfix_kGainSq5_ptr = (int16_t*)&WebRtcIlbcfix_kGainSq5[i];
}
}
gainPtr++;
}
gain_index[0]=j;
return;
}
void WebRtcIlbcfix_CbSearchCore(
int32_t *cDot, /* (i) Cross Correlation */
int16_t range, /* (i) Search range */
int16_t stage, /* (i) Stage of this search */
int16_t *inverseEnergy, /* (i) Inversed energy */
int16_t *inverseEnergyShift, /* (i) Shifts of inversed energy
with the offset 2*16-29 */
int32_t *Crit, /* (o) The criteria */
int16_t *bestIndex, /* (o) Index that corresponds to
maximum criteria (in this
vector) */
int32_t *bestCrit, /* (o) Value of critera for the
chosen index */
int16_t *bestCritSh) /* (o) The domain of the chosen
criteria */
{
int32_t maxW32, tmp32;
int16_t max, sh, tmp16;
int i;
int32_t *cDotPtr;
int16_t cDotSqW16;
int16_t *inverseEnergyPtr;
int32_t *critPtr;
int16_t *inverseEnergyShiftPtr;
/* Don't allow negative values for stage 0 */
if (stage==0) {
cDotPtr=cDot;
for (i=0;i<range;i++) {
*cDotPtr=WEBRTC_SPL_MAX(0, (*cDotPtr));
cDotPtr++;
}
}
/* Normalize cDot to int16_t, calculate the square of cDot and store the upper int16_t */
maxW32 = WebRtcSpl_MaxAbsValueW32(cDot, range);
sh = (int16_t)WebRtcSpl_NormW32(maxW32);
cDotPtr = cDot;
inverseEnergyPtr = inverseEnergy;
critPtr = Crit;
inverseEnergyShiftPtr=inverseEnergyShift;
max=WEBRTC_SPL_WORD16_MIN;
for (i=0;i<range;i++) {
/* Calculate cDot*cDot and put the result in a int16_t */
tmp32 = WEBRTC_SPL_LSHIFT_W32(*cDotPtr,sh);
tmp16 = (int16_t)WEBRTC_SPL_RSHIFT_W32(tmp32,16);
cDotSqW16 = (int16_t)(((int32_t)(tmp16)*(tmp16))>>16);
/* Calculate the criteria (cDot*cDot/energy) */
*critPtr=WEBRTC_SPL_MUL_16_16(cDotSqW16, (*inverseEnergyPtr));
/* Extract the maximum shift value under the constraint
that the criteria is not zero */
if ((*critPtr)!=0) {
max = WEBRTC_SPL_MAX((*inverseEnergyShiftPtr), max);
}
inverseEnergyPtr++;
inverseEnergyShiftPtr++;
critPtr++;
cDotPtr++;
}
/* If no max shifts still at initialization value, set shift to zero */
if (max==WEBRTC_SPL_WORD16_MIN) {
max = 0;
}
/* Modify the criterias, so that all of them use the same Q domain */
critPtr=Crit;
inverseEnergyShiftPtr=inverseEnergyShift;
for (i=0;i<range;i++) {
/* Guarantee that the shift value is less than 16
in order to simplify for DSP's (and guard against >31) */
tmp16 = WEBRTC_SPL_MIN(16, max-(*inverseEnergyShiftPtr));
(*critPtr)=WEBRTC_SPL_SHIFT_W32((*critPtr),-tmp16);
critPtr++;
inverseEnergyShiftPtr++;
}
/* Find the index of the best value */
*bestIndex = WebRtcSpl_MaxIndexW32(Crit, range);
*bestCrit = Crit[*bestIndex];
/* Calculate total shifts of this criteria */
*bestCritSh = 32 - 2*sh + max;
return;
}
// Compute speech/noise probability
// speech/noise probability is returned in: probSpeechFinal
//snrLocPrior is the prior SNR for each frequency (in Q11)
//snrLocPost is the post SNR for each frequency (in Q11)
void WebRtcNsx_SpeechNoiseProb(NsxInst_t* inst,
uint16_t* nonSpeechProbFinal,
uint32_t* priorLocSnr,
uint32_t* postLocSnr) {
uint32_t zeros, num, den, tmpU32no1, tmpU32no2, tmpU32no3;
int32_t invLrtFX, indPriorFX, tmp32, tmp32no1, tmp32no2, besselTmpFX32;
int32_t frac32, logTmp;
int32_t logLrtTimeAvgKsumFX;
int16_t indPriorFX16;
int16_t tmp16, tmp16no1, tmp16no2, tmpIndFX, tableIndex, frac, intPart;
int i, normTmp, normTmp2, nShifts;
// compute feature based on average LR factor
// this is the average over all frequencies of the smooth log LRT
logLrtTimeAvgKsumFX = 0;
for (i = 0; i < inst->magnLen; i++) {
besselTmpFX32 = (int32_t)postLocSnr[i]; // Q11
normTmp = WebRtcSpl_NormU32(postLocSnr[i]);
num = WEBRTC_SPL_LSHIFT_U32(postLocSnr[i], normTmp); // Q(11+normTmp)
if (normTmp > 10) {
den = WEBRTC_SPL_LSHIFT_U32(priorLocSnr[i], normTmp - 11); // Q(normTmp)
} else {
den = WEBRTC_SPL_RSHIFT_U32(priorLocSnr[i], 11 - normTmp); // Q(normTmp)
}
if (den > 0) {
besselTmpFX32 -= WEBRTC_SPL_UDIV(num, den); // Q11
} else {
besselTmpFX32 -= num; // Q11
}
// inst->logLrtTimeAvg[i] += LRT_TAVG * (besselTmp - log(snrLocPrior)
// - inst->logLrtTimeAvg[i]);
// Here, LRT_TAVG = 0.5
zeros = WebRtcSpl_NormU32(priorLocSnr[i]);
frac32 = (int32_t)(((priorLocSnr[i] << zeros) & 0x7FFFFFFF) >> 19);
tmp32 = WEBRTC_SPL_MUL(frac32, frac32);
tmp32 = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL(tmp32, -43), 19);
tmp32 += WEBRTC_SPL_MUL_16_16_RSFT((int16_t)frac32, 5412, 12);
frac32 = tmp32 + 37;
// tmp32 = log2(priorLocSnr[i])
tmp32 = (int32_t)(((31 - zeros) << 12) + frac32) - (11 << 12); // Q12
logTmp = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL_32_16(tmp32, 178), 8);
// log2(priorLocSnr[i])*log(2)
tmp32no1 = WEBRTC_SPL_RSHIFT_W32(logTmp + inst->logLrtTimeAvgW32[i], 1);
// Q12
inst->logLrtTimeAvgW32[i] += (besselTmpFX32 - tmp32no1); // Q12
logLrtTimeAvgKsumFX += inst->logLrtTimeAvgW32[i]; // Q12
}
inst->featureLogLrt = WEBRTC_SPL_RSHIFT_W32(logLrtTimeAvgKsumFX * 5,
inst->stages + 10);
// 5 = BIN_SIZE_LRT / 2
// done with computation of LR factor
//
//compute the indicator functions
//
// average LRT feature
// FLOAT code
// indicator0 = 0.5 * (tanh(widthPrior *
// (logLrtTimeAvgKsum - threshPrior0)) + 1.0);
tmpIndFX = 16384; // Q14(1.0)
tmp32no1 = logLrtTimeAvgKsumFX - inst->thresholdLogLrt; // Q12
nShifts = 7 - inst->stages; // WIDTH_PR_MAP_SHIFT - inst->stages + 5;
//use larger width in tanh map for pause regions
if (tmp32no1 < 0) {
tmpIndFX = 0;
tmp32no1 = -tmp32no1;
//widthPrior = widthPrior * 2.0;
nShifts++;
}
tmp32no1 = WEBRTC_SPL_SHIFT_W32(tmp32no1, nShifts); // Q14
// compute indicator function: sigmoid map
tableIndex = (int16_t)WEBRTC_SPL_RSHIFT_W32(tmp32no1, 14);
if ((tableIndex < 16) && (tableIndex >= 0)) {
tmp16no2 = kIndicatorTable[tableIndex];
tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
frac = (int16_t)(tmp32no1 & 0x00003fff); // Q14
tmp16no2 += (int16_t)WEBRTC_SPL_MUL_16_16_RSFT(tmp16no1, frac, 14);
if (tmpIndFX == 0) {
tmpIndFX = 8192 - tmp16no2; // Q14
} else {
tmpIndFX = 8192 + tmp16no2; // Q14
}
}
indPriorFX = WEBRTC_SPL_MUL_16_16(inst->weightLogLrt, tmpIndFX); // 6*Q14
//spectral flatness feature
if (inst->weightSpecFlat) {
tmpU32no1 = WEBRTC_SPL_UMUL(inst->featureSpecFlat, 400); // Q10
tmpIndFX = 16384; // Q14(1.0)
//use larger width in tanh map for pause regions
tmpU32no2 = inst->thresholdSpecFlat - tmpU32no1; //Q10
nShifts = 4;
if (inst->thresholdSpecFlat < tmpU32no1) {
tmpIndFX = 0;
tmpU32no2 = tmpU32no1 - inst->thresholdSpecFlat;
//widthPrior = widthPrior * 2.0;
nShifts++;
}
tmp32no1 = (int32_t)WebRtcSpl_DivU32U16(WEBRTC_SPL_LSHIFT_U32(tmpU32no2,
nShifts), 25);
//Q14
tmpU32no1 = WebRtcSpl_DivU32U16(WEBRTC_SPL_LSHIFT_U32(tmpU32no2, nShifts),
25); //Q14
// compute indicator function: sigmoid map
// FLOAT code
// indicator1 = 0.5 * (tanh(sgnMap * widthPrior *
// (threshPrior1 - tmpFloat1)) + 1.0);
tableIndex = (int16_t)WEBRTC_SPL_RSHIFT_U32(tmpU32no1, 14);
if (tableIndex < 16) {
tmp16no2 = kIndicatorTable[tableIndex];
tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
frac = (int16_t)(tmpU32no1 & 0x00003fff); // Q14
tmp16no2 += (int16_t)WEBRTC_SPL_MUL_16_16_RSFT(tmp16no1, frac, 14);
if (tmpIndFX) {
tmpIndFX = 8192 + tmp16no2; // Q14
} else {
tmpIndFX = 8192 - tmp16no2; // Q14
}
}
indPriorFX += WEBRTC_SPL_MUL_16_16(inst->weightSpecFlat, tmpIndFX); // 6*Q14
}
//for template spectral-difference
if (inst->weightSpecDiff) {
tmpU32no1 = 0;
if (inst->featureSpecDiff) {
normTmp = WEBRTC_SPL_MIN(20 - inst->stages,
WebRtcSpl_NormU32(inst->featureSpecDiff));
tmpU32no1 = WEBRTC_SPL_LSHIFT_U32(inst->featureSpecDiff, normTmp);
// Q(normTmp-2*stages)
tmpU32no2 = WEBRTC_SPL_RSHIFT_U32(inst->timeAvgMagnEnergy,
20 - inst->stages - normTmp);
if (tmpU32no2 > 0) {
// Q(20 - inst->stages)
tmpU32no1 = WEBRTC_SPL_UDIV(tmpU32no1, tmpU32no2);
} else {
tmpU32no1 = (uint32_t)(0x7fffffff);
}
}
tmpU32no3 = WEBRTC_SPL_UDIV(WEBRTC_SPL_LSHIFT_U32(inst->thresholdSpecDiff,
17),
25);
tmpU32no2 = tmpU32no1 - tmpU32no3;
nShifts = 1;
tmpIndFX = 16384; // Q14(1.0)
//use larger width in tanh map for pause regions
if (tmpU32no2 & 0x80000000) {
tmpIndFX = 0;
tmpU32no2 = tmpU32no3 - tmpU32no1;
//widthPrior = widthPrior * 2.0;
nShifts--;
}
tmpU32no1 = WEBRTC_SPL_RSHIFT_U32(tmpU32no2, nShifts);
// compute indicator function: sigmoid map
/* FLOAT code
indicator2 = 0.5 * (tanh(widthPrior * (tmpFloat1 - threshPrior2)) + 1.0);
*/
tableIndex = (int16_t)WEBRTC_SPL_RSHIFT_U32(tmpU32no1, 14);
if (tableIndex < 16) {
tmp16no2 = kIndicatorTable[tableIndex];
tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
frac = (int16_t)(tmpU32no1 & 0x00003fff); // Q14
tmp16no2 += (int16_t)WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(
tmp16no1, frac, 14);
if (tmpIndFX) {
tmpIndFX = 8192 + tmp16no2;
} else {
tmpIndFX = 8192 - tmp16no2;
}
}
indPriorFX += WEBRTC_SPL_MUL_16_16(inst->weightSpecDiff, tmpIndFX); // 6*Q14
}
//combine the indicator function with the feature weights
// FLOAT code
// indPrior = 1 - (weightIndPrior0 * indicator0 + weightIndPrior1 *
// indicator1 + weightIndPrior2 * indicator2);
indPriorFX16 = WebRtcSpl_DivW32W16ResW16(98307 - indPriorFX, 6); // Q14
// done with computing indicator function
//compute the prior probability
// FLOAT code
// inst->priorNonSpeechProb += PRIOR_UPDATE *
// (indPriorNonSpeech - inst->priorNonSpeechProb);
tmp16 = indPriorFX16 - inst->priorNonSpeechProb; // Q14
inst->priorNonSpeechProb += (int16_t)WEBRTC_SPL_MUL_16_16_RSFT(
PRIOR_UPDATE_Q14, tmp16, 14); // Q14
//final speech probability: combine prior model with LR factor:
memset(nonSpeechProbFinal, 0, sizeof(uint16_t) * inst->magnLen);
if (inst->priorNonSpeechProb > 0) {
for (i = 0; i < inst->magnLen; i++) {
// FLOAT code
// invLrt = exp(inst->logLrtTimeAvg[i]);
// invLrt = inst->priorSpeechProb * invLrt;
// nonSpeechProbFinal[i] = (1.0 - inst->priorSpeechProb) /
// (1.0 - inst->priorSpeechProb + invLrt);
// invLrt = (1.0 - inst->priorNonSpeechProb) * invLrt;
// nonSpeechProbFinal[i] = inst->priorNonSpeechProb /
// (inst->priorNonSpeechProb + invLrt);
if (inst->logLrtTimeAvgW32[i] < 65300) {
tmp32no1 = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL(
inst->logLrtTimeAvgW32[i], 23637),
14); // Q12
intPart = (int16_t)WEBRTC_SPL_RSHIFT_W32(tmp32no1, 12);
if (intPart < -8) {
intPart = -8;
}
frac = (int16_t)(tmp32no1 & 0x00000fff); // Q12
// Quadratic approximation of 2^frac
tmp32no2 = WEBRTC_SPL_RSHIFT_W32(frac * frac * 44, 19); // Q12
tmp32no2 += WEBRTC_SPL_MUL_16_16_RSFT(frac, 84, 7); // Q12
invLrtFX = WEBRTC_SPL_LSHIFT_W32(1, 8 + intPart)
+ WEBRTC_SPL_SHIFT_W32(tmp32no2, intPart - 4); // Q8
normTmp = WebRtcSpl_NormW32(invLrtFX);
normTmp2 = WebRtcSpl_NormW16((16384 - inst->priorNonSpeechProb));
if (normTmp + normTmp2 >= 7) {
if (normTmp + normTmp2 < 15) {
invLrtFX = WEBRTC_SPL_RSHIFT_W32(invLrtFX, 15 - normTmp2 - normTmp);
// Q(normTmp+normTmp2-7)
tmp32no1 = WEBRTC_SPL_MUL_32_16(invLrtFX,
(16384 - inst->priorNonSpeechProb));
// Q(normTmp+normTmp2+7)
invLrtFX = WEBRTC_SPL_SHIFT_W32(tmp32no1, 7 - normTmp - normTmp2);
// Q14
} else {
tmp32no1 = WEBRTC_SPL_MUL_32_16(invLrtFX,
(16384 - inst->priorNonSpeechProb));
// Q22
invLrtFX = WEBRTC_SPL_RSHIFT_W32(tmp32no1, 8); // Q14
}
tmp32no1 = WEBRTC_SPL_LSHIFT_W32((int32_t)inst->priorNonSpeechProb,
8); // Q22
nonSpeechProbFinal[i] = (uint16_t)WEBRTC_SPL_DIV(tmp32no1,
(int32_t)inst->priorNonSpeechProb + invLrtFX); // Q8
}
}
}
}
}
/* MA filter */
void WebRtcIsacfix_NormLatticeFilterMa(int16_t orderCoef,
int32_t *stateGQ15,
int16_t *lat_inQ0,
int16_t *filt_coefQ15,
int32_t *gain_lo_hiQ17,
int16_t lo_hi,
int16_t *lat_outQ9)
{
int16_t sthQ15[MAX_AR_MODEL_ORDER];
int16_t cthQ15[MAX_AR_MODEL_ORDER];
int u, i, k, n;
int16_t temp2,temp3;
int16_t ord_1 = orderCoef+1;
int32_t inv_cthQ16[MAX_AR_MODEL_ORDER];
int32_t gain32, fQtmp;
int16_t gain16;
int16_t gain_sh;
int32_t tmp32, tmp32b;
int32_t fQ15vec[HALF_SUBFRAMELEN];
int32_t gQ15[MAX_AR_MODEL_ORDER+1][HALF_SUBFRAMELEN];
int16_t sh;
int16_t t16a;
int16_t t16b;
for (u=0;u<SUBFRAMES;u++)
{
int32_t temp1 = WEBRTC_SPL_MUL_16_16(u, HALF_SUBFRAMELEN);
/* set the Direct Form coefficients */
temp2 = (int16_t)WEBRTC_SPL_MUL_16_16(u, orderCoef);
temp3 = (int16_t)WEBRTC_SPL_MUL_16_16(2, u)+lo_hi;
/* compute lattice filter coefficients */
memcpy(sthQ15, &filt_coefQ15[temp2], orderCoef * sizeof(int16_t));
WebRtcSpl_SqrtOfOneMinusXSquared(sthQ15, orderCoef, cthQ15);
/* compute the gain */
gain32 = gain_lo_hiQ17[temp3];
gain_sh = WebRtcSpl_NormW32(gain32);
gain32 = WEBRTC_SPL_LSHIFT_W32(gain32, gain_sh); //Q(17+gain_sh)
for (k=0;k<orderCoef;k++)
{
gain32 = WEBRTC_SPL_MUL_16_32_RSFT15(cthQ15[k], gain32); //Q15*Q(17+gain_sh)>>15 = Q(17+gain_sh)
inv_cthQ16[k] = WebRtcSpl_DivW32W16((int32_t)2147483647, cthQ15[k]); // 1/cth[k] in Q31/Q15 = Q16
}
gain16 = (int16_t)(gain32 >> 16); // Q(1+gain_sh).
/* normalized lattice filter */
/*****************************/
/* initial conditions */
for (i=0;i<HALF_SUBFRAMELEN;i++)
{
fQ15vec[i] = WEBRTC_SPL_LSHIFT_W32((int32_t)lat_inQ0[i + temp1], 15); //Q15
gQ15[0][i] = WEBRTC_SPL_LSHIFT_W32((int32_t)lat_inQ0[i + temp1], 15); //Q15
}
fQtmp = fQ15vec[0];
/* get the state of f&g for the first input, for all orders */
for (i=1;i<ord_1;i++)
{
// Calculate f[i][0] = inv_cth[i-1]*(f[i-1][0] + sth[i-1]*stateG[i-1]);
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT15(sthQ15[i-1], stateGQ15[i-1]);//Q15*Q15>>15 = Q15
tmp32b= fQtmp + tmp32; //Q15+Q15=Q15
tmp32 = inv_cthQ16[i-1]; //Q16
t16a = (int16_t)(tmp32 >> 16);
t16b = (int16_t) (tmp32-WEBRTC_SPL_LSHIFT_W32(((int32_t)t16a), 16));
if (t16b<0) t16a++;
tmp32 = LATTICE_MUL_32_32_RSFT16(t16a, t16b, tmp32b);
fQtmp = tmp32; // Q15
// Calculate g[i][0] = cth[i-1]*stateG[i-1] + sth[i-1]* f[i][0];
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT15(cthQ15[i-1], stateGQ15[i-1]); //Q15*Q15>>15 = Q15
tmp32b = WEBRTC_SPL_MUL_16_32_RSFT15(sthQ15[i-1], fQtmp); //Q15*Q15>>15 = Q15
tmp32 = tmp32 + tmp32b;//Q15+Q15 = Q15
gQ15[i][0] = tmp32; // Q15
}
/* filtering */
/* save the states */
for(k=0;k<orderCoef;k++)
{
// for 0 <= n < HALF_SUBFRAMELEN - 1:
// f[k+1][n+1] = inv_cth[k]*(f[k][n+1] + sth[k]*g[k][n]);
// g[k+1][n+1] = cth[k]*g[k][n] + sth[k]* f[k+1][n+1];
WebRtcIsacfix_FilterMaLoopFix(sthQ15[k], cthQ15[k], inv_cthQ16[k],
&gQ15[k][0], &gQ15[k+1][1], &fQ15vec[1]);
}
fQ15vec[0] = fQtmp;
for(n=0;n<HALF_SUBFRAMELEN;n++)
{
//gain32 >>= gain_sh; // Q(17+gain_sh) -> Q17
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT16(gain16, fQ15vec[n]); //Q(1+gain_sh)*Q15>>16 = Q(gain_sh)
sh = 9-gain_sh; //number of needed shifts to reach Q9
t16a = (int16_t) WEBRTC_SPL_SHIFT_W32(tmp32, sh);
lat_outQ9[n + temp1] = t16a;
}
/* save the states */
for (i=0;i<ord_1;i++)
{
stateGQ15[i] = gQ15[i][HALF_SUBFRAMELEN-1];
}
//process next frame
}
return;
}
/* filter the signal using normalized lattice filter */
void WebRtcIsacfix_NormLatticeFilterAr(int16_t orderCoef,
int16_t *stateGQ0,
int32_t *lat_inQ25,
int16_t *filt_coefQ15,
int32_t *gain_lo_hiQ17,
int16_t lo_hi,
int16_t *lat_outQ0)
{
int ii,n,k,i,u;
int16_t sthQ15[MAX_AR_MODEL_ORDER];
int16_t cthQ15[MAX_AR_MODEL_ORDER];
int32_t tmp32;
int16_t tmpAR;
int16_t ARfQ0vec[HALF_SUBFRAMELEN];
int16_t ARgQ0vec[MAX_AR_MODEL_ORDER+1];
int32_t inv_gain32;
int16_t inv_gain16;
int16_t den16;
int16_t sh;
int16_t temp2,temp3;
int16_t ord_1 = orderCoef+1;
for (u=0;u<SUBFRAMES;u++)
{
int32_t temp1 = WEBRTC_SPL_MUL_16_16(u, HALF_SUBFRAMELEN);
//set the denominator and numerator of the Direct Form
temp2 = (int16_t)WEBRTC_SPL_MUL_16_16(u, orderCoef);
temp3 = (int16_t)WEBRTC_SPL_MUL_16_16(2, u) + lo_hi;
for (ii=0; ii<orderCoef; ii++) {
sthQ15[ii] = filt_coefQ15[temp2+ii];
}
WebRtcSpl_SqrtOfOneMinusXSquared(sthQ15, orderCoef, cthQ15);
/* Simulation of the 25 files shows that maximum value in
the vector gain_lo_hiQ17[] is 441344, which means that
it is log2((2^31)/441344) = 12.2 shifting bits from
saturation. Therefore, it should be safe to use Q27 instead
of Q17. */
tmp32 = WEBRTC_SPL_LSHIFT_W32(gain_lo_hiQ17[temp3], 10); // Q27
for (k=0;k<orderCoef;k++) {
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT15(cthQ15[k], tmp32); // Q15*Q27>>15 = Q27
}
sh = WebRtcSpl_NormW32(tmp32); // tmp32 is the gain
den16 = (int16_t) WEBRTC_SPL_SHIFT_W32(tmp32, sh-16); //Q(27+sh-16) = Q(sh+11) (all 16 bits are value bits)
inv_gain32 = WebRtcSpl_DivW32W16((int32_t)2147483647, den16); // 1/gain in Q31/Q(sh+11) = Q(20-sh)
//initial conditions
inv_gain16 = (int16_t)(inv_gain32 >> 2); // 1/gain in Q(20-sh-2) = Q(18-sh)
for (i=0;i<HALF_SUBFRAMELEN;i++)
{
tmp32 = WEBRTC_SPL_LSHIFT_W32(lat_inQ25[i + temp1], 1); //Q25->Q26
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT16(inv_gain16, tmp32); //lat_in[]*inv_gain in (Q(18-sh)*Q26)>>16 = Q(28-sh)
tmp32 = WEBRTC_SPL_SHIFT_W32(tmp32, -(28-sh)); // lat_in[]*inv_gain in Q0
ARfQ0vec[i] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
}
for (i=orderCoef-1;i>=0;i--) //get the state of f&g for the first input, for all orders
{
tmp32 = (cthQ15[i] * ARfQ0vec[0] - sthQ15[i] * stateGQ0[i] + 16384) >> 15;
tmpAR = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
tmp32 = (sthQ15[i] * ARfQ0vec[0] + cthQ15[i] * stateGQ0[i] + 16384) >> 15;
ARgQ0vec[i+1] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
ARfQ0vec[0] = tmpAR;
}
ARgQ0vec[0] = ARfQ0vec[0];
// Filter ARgQ0vec[] and ARfQ0vec[] through coefficients cthQ15[] and sthQ15[].
WebRtcIsacfix_FilterArLoop(ARgQ0vec, ARfQ0vec, cthQ15, sthQ15, orderCoef);
for(n=0;n<HALF_SUBFRAMELEN;n++)
{
lat_outQ0[n + temp1] = ARfQ0vec[n];
}
/* cannot use memcpy in the following */
for (i=0;i<ord_1;i++)
{
stateGQ0[i] = ARgQ0vec[i];
}
}
return;
}
void WebRtcIlbcfix_CbUpdateBestIndex(
WebRtc_Word32 CritNew, /* (i) New Potentially best Criteria */
WebRtc_Word16 CritNewSh, /* (i) Shift value of above Criteria */
WebRtc_Word16 IndexNew, /* (i) Index of new Criteria */
WebRtc_Word32 cDotNew, /* (i) Cross dot of new index */
WebRtc_Word16 invEnergyNew, /* (i) Inversed energy new index */
WebRtc_Word16 energyShiftNew, /* (i) Energy shifts of new index */
WebRtc_Word32 *CritMax, /* (i/o) Maximum Criteria (so far) */
WebRtc_Word16 *shTotMax, /* (i/o) Shifts of maximum criteria */
WebRtc_Word16 *bestIndex, /* (i/o) Index that corresponds to
maximum criteria */
WebRtc_Word16 *bestGain) /* (i/o) Gain in Q14 that corresponds
to maximum criteria */
{
WebRtc_Word16 shOld, shNew, tmp16;
WebRtc_Word16 scaleTmp;
WebRtc_Word32 gainW32;
/* Normalize the new and old Criteria to the same domain */
if (CritNewSh>(*shTotMax)) {
shOld=WEBRTC_SPL_MIN(31,CritNewSh-(*shTotMax));
shNew=0;
} else {
shOld=0;
shNew=WEBRTC_SPL_MIN(31,(*shTotMax)-CritNewSh);
}
/* Compare the two criterias. If the new one is better,
calculate the gain and store this index as the new best one
*/
if (WEBRTC_SPL_RSHIFT_W32(CritNew, shNew)>
WEBRTC_SPL_RSHIFT_W32((*CritMax),shOld)) {
tmp16 = (WebRtc_Word16)WebRtcSpl_NormW32(cDotNew);
tmp16 = 16 - tmp16;
/* Calculate the gain in Q14
Compensate for inverseEnergyshift in Q29 and that the energy
value was stored in a WebRtc_Word16 (shifted down 16 steps)
=> 29-14+16 = 31 */
scaleTmp = -energyShiftNew-tmp16+31;
scaleTmp = WEBRTC_SPL_MIN(31, scaleTmp);
gainW32 = WEBRTC_SPL_MUL_16_16_RSFT(
((WebRtc_Word16)WEBRTC_SPL_SHIFT_W32(cDotNew, -tmp16)), invEnergyNew, scaleTmp);
/* Check if criteria satisfies Gain criteria (max 1.3)
if it is larger set the gain to 1.3
(slightly different from FLP version)
*/
if (gainW32>21299) {
*bestGain=21299;
} else if (gainW32<-21299) {
*bestGain=-21299;
} else {
*bestGain=(WebRtc_Word16)gainW32;
}
*CritMax=CritNew;
*shTotMax=CritNewSh;
*bestIndex = IndexNew;
}
return;
}
/* filter the signal using normalized lattice filter */
void WebRtcIsacfix_NormLatticeFilterAr(size_t orderCoef,
int16_t *stateGQ0,
int32_t *lat_inQ25,
int16_t *filt_coefQ15,
int32_t *gain_lo_hiQ17,
int16_t lo_hi,
int16_t *lat_outQ0)
{
size_t ii, k, i;
int n, u;
int16_t sthQ15[MAX_AR_MODEL_ORDER];
int16_t cthQ15[MAX_AR_MODEL_ORDER];
int32_t tmp32;
int16_t tmpAR;
int16_t ARfQ0vec[HALF_SUBFRAMELEN];
int16_t ARgQ0vec[MAX_AR_MODEL_ORDER+1];
int32_t inv_gain32;
int16_t inv_gain16;
int16_t den16;
int16_t sh;
int16_t temp2,temp3;
size_t ord_1 = orderCoef+1;
for (u=0;u<SUBFRAMES;u++)
{
int32_t temp1 = u * HALF_SUBFRAMELEN;
//set the denominator and numerator of the Direct Form
temp2 = (int16_t)(u * orderCoef);
temp3 = (int16_t)(2 * u + lo_hi);
for (ii=0; ii<orderCoef; ii++) {
sthQ15[ii] = filt_coefQ15[temp2+ii];
}
WebRtcSpl_SqrtOfOneMinusXSquared(sthQ15, orderCoef, cthQ15);
// Originally, this line was assumed to never overflow, since "[s]imulation
// of the 25 files shows that maximum value in the vector gain_lo_hiQ17[]
// is 441344, which means that it is log2((2^31)/441344) = 12.2 shifting
// bits from saturation. Therefore, it should be safe to use Q27 instead of
// Q17." However, a fuzzer test succeeded in provoking an overflow here,
// which we ignore on the theory that only "abnormal" inputs cause
// overflow.
tmp32 = OverflowingLShiftS32(gain_lo_hiQ17[temp3], 10); // Q27
for (k=0;k<orderCoef;k++) {
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT15(cthQ15[k], tmp32); // Q15*Q27>>15 = Q27
}
sh = WebRtcSpl_NormW32(tmp32); // tmp32 is the gain
den16 = (int16_t) WEBRTC_SPL_SHIFT_W32(tmp32, sh-16); //Q(27+sh-16) = Q(sh+11) (all 16 bits are value bits)
inv_gain32 = WebRtcSpl_DivW32W16((int32_t)2147483647, den16); // 1/gain in Q31/Q(sh+11) = Q(20-sh)
//initial conditions
inv_gain16 = (int16_t)(inv_gain32 >> 2); // 1/gain in Q(20-sh-2) = Q(18-sh)
for (i=0;i<HALF_SUBFRAMELEN;i++)
{
tmp32 = OverflowingLShiftS32(lat_inQ25[i + temp1], 1); // Q25->Q26
tmp32 = WEBRTC_SPL_MUL_16_32_RSFT16(inv_gain16, tmp32); //lat_in[]*inv_gain in (Q(18-sh)*Q26)>>16 = Q(28-sh)
tmp32 = WEBRTC_SPL_SHIFT_W32(tmp32, -(28-sh)); // lat_in[]*inv_gain in Q0
ARfQ0vec[i] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
}
// Get the state of f & g for the first input, for all orders.
for (i = orderCoef; i > 0; i--)
{
tmp32 = (cthQ15[i - 1] * ARfQ0vec[0] - sthQ15[i - 1] * stateGQ0[i - 1] +
16384) >> 15;
tmpAR = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
tmp32 = (sthQ15[i - 1] * ARfQ0vec[0] + cthQ15[i - 1] * stateGQ0[i - 1] +
16384) >> 15;
ARgQ0vec[i] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
ARfQ0vec[0] = tmpAR;
}
ARgQ0vec[0] = ARfQ0vec[0];
// Filter ARgQ0vec[] and ARfQ0vec[] through coefficients cthQ15[] and sthQ15[].
WebRtcIsacfix_FilterArLoop(ARgQ0vec, ARfQ0vec, cthQ15, sthQ15, orderCoef);
for(n=0;n<HALF_SUBFRAMELEN;n++)
{
lat_outQ0[n + temp1] = ARfQ0vec[n];
}
/* cannot use memcpy in the following */
for (i=0;i<ord_1;i++)
{
stateGQ0[i] = ARgQ0vec[i];
}
}
return;
}