public virtual int Decode(Bits bits, float[] xout)
{
int num = 0;
float[] array = new float[3];
float num2 = 0f;
int num3 = 40;
float num4 = 0f;
float num5 = 0f;
if (bits == null && this.dtx_enabled != 0)
{
this.submodeID = 0;
}
else
{
if (bits == null)
{
this.DecodeLost(xout);
return(0);
}
while (bits.BitsRemaining() >= 5)
{
int num6;
if (bits.Unpack(1) != 0)
{
num6 = bits.Unpack(3);
int num7 = SbCodec.SB_FRAME_SIZE[num6];
if (num7 < 0)
{
throw new InvalidFormatException("Invalid sideband mode encountered (1st sideband): " + num6);
}
num7 -= 4;
bits.Advance(num7);
if (bits.Unpack(1) != 0)
{
num6 = bits.Unpack(3);
num7 = SbCodec.SB_FRAME_SIZE[num6];
if (num7 < 0)
{
throw new InvalidFormatException("Invalid sideband mode encountered. (2nd sideband): " + num6);
}
num7 -= 4;
bits.Advance(num7);
if (bits.Unpack(1) != 0)
{
throw new InvalidFormatException("More than two sideband layers found");
}
}
}
if (bits.BitsRemaining() < 4)
{
return(1);
}
num6 = bits.Unpack(4);
if (num6 == 15)
{
return(1);
}
if (num6 == 14)
{
this.inband.SpeexInbandRequest(bits);
}
else if (num6 == 13)
{
this.inband.UserInbandRequest(bits);
}
else if (num6 > 8)
{
throw new InvalidFormatException("Invalid mode encountered: " + num6);
}
if (num6 <= 8)
{
this.submodeID = num6;
goto IL_199;
}
}
return(-1);
}
IL_199:
Array.Copy(this.frmBuf, this.frameSize, this.frmBuf, 0, this.bufSize - this.frameSize);
Array.Copy(this.excBuf, this.frameSize, this.excBuf, 0, this.bufSize - this.frameSize);
if (this.submodes[this.submodeID] == null)
{
Filters.Bw_lpc(0.93f, this.interp_qlpc, this.lpc, 10);
float num8 = 0f;
for (int i = 0; i < this.frameSize; i++)
{
num8 += this.innov[i] * this.innov[i];
}
num8 = (float)Math.Sqrt((double)(num8 / (float)this.frameSize));
for (int i = this.excIdx; i < this.excIdx + this.frameSize; i++)
{
this.excBuf[i] = (float)((double)(3f * num8) * (this.random.NextDouble() - 0.5));
}
this.first = 1;
Filters.Iir_mem2(this.excBuf, this.excIdx, this.lpc, this.frmBuf, this.frmIdx, this.frameSize, this.lpcSize, this.mem_sp);
xout[0] = this.frmBuf[this.frmIdx] + this.preemph * this.pre_mem;
for (int i = 1; i < this.frameSize; i++)
{
xout[i] = this.frmBuf[this.frmIdx + i] + this.preemph * xout[i - 1];
}
this.pre_mem = xout[this.frameSize - 1];
this.count_lost = 0;
return(0);
}
this.submodes[this.submodeID].LsqQuant.Unquant(this.qlsp, this.lpcSize, bits);
if (this.count_lost != 0)
{
float num9 = 0f;
for (int i = 0; i < this.lpcSize; i++)
{
num9 += Math.Abs(this.old_qlsp[i] - this.qlsp[i]);
}
float num10 = (float)(0.6 * Math.Exp(-0.2 * (double)num9));
for (int i = 0; i < 2 * this.lpcSize; i++)
{
this.mem_sp[i] *= num10;
}
}
if (this.first != 0 || this.count_lost != 0)
{
for (int i = 0; i < this.lpcSize; i++)
{
this.old_qlsp[i] = this.qlsp[i];
}
}
if (this.submodes[this.submodeID].LbrPitch != -1)
{
num = this.min_pitch + bits.Unpack(7);
}
if (this.submodes[this.submodeID].ForcedPitchGain != 0)
{
int num11 = bits.Unpack(4);
num2 = 0.066667f * (float)num11;
}
int num12 = bits.Unpack(5);
float num13 = (float)Math.Exp((double)num12 / 3.5);
if (this.submodeID == 1)
{
int num14 = bits.Unpack(4);
if (num14 == 15)
{
this.dtx_enabled = 1;
}
else
{
this.dtx_enabled = 0;
}
}
if (this.submodeID > 1)
{
this.dtx_enabled = 0;
}
for (int j = 0; j < this.nbSubframes; j++)
{
int num15 = this.subframeSize * j;
int num16 = this.frmIdx + num15;
int num17 = this.excIdx + num15;
float num18 = (1f + (float)j) / (float)this.nbSubframes;
for (int i = 0; i < this.lpcSize; i++)
{
this.interp_qlsp[i] = (1f - num18) * this.old_qlsp[i] + num18 * this.qlsp[i];
}
Lsp.Enforce_margin(this.interp_qlsp, this.lpcSize, 0.002f);
for (int i = 0; i < this.lpcSize; i++)
{
this.interp_qlsp[i] = (float)Math.Cos((double)this.interp_qlsp[i]);
}
this.m_lsp.Lsp2lpc(this.interp_qlsp, this.interp_qlpc, this.lpcSize);
if (this.enhanced)
{
float num19 = 0.9f;
float lpcEnhK = this.submodes[this.submodeID].LpcEnhK1;
float lpcEnhK2 = this.submodes[this.submodeID].LpcEnhK2;
float gamma = (1f - (1f - num19 * lpcEnhK) / (1f - num19 * lpcEnhK2)) / num19;
Filters.Bw_lpc(lpcEnhK, this.interp_qlpc, this.awk1, this.lpcSize);
Filters.Bw_lpc(lpcEnhK2, this.interp_qlpc, this.awk2, this.lpcSize);
Filters.Bw_lpc(gamma, this.interp_qlpc, this.awk3, this.lpcSize);
}
num18 = 1f;
this.pi_gain[j] = 0f;
for (int i = 0; i <= this.lpcSize; i++)
{
this.pi_gain[j] += num18 * this.interp_qlpc[i];
num18 = -num18;
}
for (int i = 0; i < this.subframeSize; i++)
{
this.excBuf[num17 + i] = 0f;
}
int num20;
if (this.submodes[this.submodeID].LbrPitch != -1)
{
int lbrPitch = this.submodes[this.submodeID].LbrPitch;
if (lbrPitch != 0)
{
num20 = num - lbrPitch + 1;
if (num20 < this.min_pitch)
{
num20 = this.min_pitch;
}
int num21 = num + lbrPitch;
if (num21 > this.max_pitch)
{
num21 = this.max_pitch;
}
}
else
{
num20 = num;
}
}
else
{
num20 = this.min_pitch;
int num21 = this.max_pitch;
}
int num22 = this.submodes[this.submodeID].Ltp.Unquant(this.excBuf, num17, num20, num2, this.subframeSize, array, bits, this.count_lost, num15, this.last_pitch_gain);
if (this.count_lost != 0 && num13 < this.last_ol_gain)
{
float num23 = num13 / (this.last_ol_gain + 1f);
for (int i = 0; i < this.subframeSize; i++)
{
this.excBuf[this.excIdx + i] *= num23;
}
}
num18 = Math.Abs(array[0] + array[1] + array[2]);
num18 = Math.Abs(array[1]);
if (array[0] > 0f)
{
num18 += array[0];
}
else
{
num18 -= 0.5f * array[0];
}
if (array[2] > 0f)
{
num18 += array[2];
}
else
{
num18 -= 0.5f * array[0];
}
num5 += num18;
if (num18 > num4)
{
num3 = num22;
num4 = num18;
}
int num24 = j * this.subframeSize;
for (int i = num24; i < num24 + this.subframeSize; i++)
{
this.innov[i] = 0f;
}
float num26;
if (this.submodes[this.submodeID].HaveSubframeGain == 3)
{
int num25 = bits.Unpack(3);
num26 = (float)((double)num13 * Math.Exp((double)NbCodec.exc_gain_quant_scal3[num25]));
}
else if (this.submodes[this.submodeID].HaveSubframeGain == 1)
{
int num25 = bits.Unpack(1);
num26 = (float)((double)num13 * Math.Exp((double)NbCodec.exc_gain_quant_scal1[num25]));
}
else
{
num26 = num13;
}
if (this.submodes[this.submodeID].Innovation != null)
{
this.submodes[this.submodeID].Innovation.Unquantify(this.innov, num24, this.subframeSize, bits);
}
for (int i = num24; i < num24 + this.subframeSize; i++)
{
this.innov[i] *= num26;
}
if (this.submodeID == 1)
{
float num27 = num2;
for (int i = 0; i < this.subframeSize; i++)
{
this.excBuf[num17 + i] = 0f;
}
while (this.voc_offset < this.subframeSize)
{
if (this.voc_offset >= 0)
{
this.excBuf[num17 + this.voc_offset] = (float)Math.Sqrt((double)(1f * (float)num));
}
this.voc_offset += num;
}
this.voc_offset -= this.subframeSize;
num27 = 0.5f + 2f * (num27 - 0.6f);
if (num27 < 0f)
{
num27 = 0f;
}
if (num27 > 1f)
{
num27 = 1f;
}
for (int i = 0; i < this.subframeSize; i++)
{
float voc_m = this.excBuf[num17 + i];
this.excBuf[num17 + i] = 0.8f * num27 * this.excBuf[num17 + i] * num13 + 0.6f * num27 * this.voc_m1 * num13 + 0.5f * num27 * this.innov[num24 + i] - 0.5f * num27 * this.voc_m2 + (1f - num27) * this.innov[num24 + i];
this.voc_m1 = voc_m;
this.voc_m2 = this.innov[num24 + i];
this.voc_mean = 0.95f * this.voc_mean + 0.05f * this.excBuf[num17 + i];
this.excBuf[num17 + i] -= this.voc_mean;
}
}
else
{
for (int i = 0; i < this.subframeSize; i++)
{
this.excBuf[num17 + i] += this.innov[num24 + i];
}
}
if (this.submodes[this.submodeID].DoubleCodebook != 0)
{
for (int i = 0; i < this.subframeSize; i++)
{
this.innov2[i] = 0f;
}
this.submodes[this.submodeID].Innovation.Unquantify(this.innov2, 0, this.subframeSize, bits);
for (int i = 0; i < this.subframeSize; i++)
{
this.innov2[i] *= num26 * 0.454545438f;
}
for (int i = 0; i < this.subframeSize; i++)
{
this.excBuf[num17 + i] += this.innov2[i];
}
}
for (int i = 0; i < this.subframeSize; i++)
{
this.frmBuf[num16 + i] = this.excBuf[num17 + i];
}
if (this.enhanced && this.submodes[this.submodeID].CombGain > 0f)
{
this.filters.Comb_filter(this.excBuf, num17, this.frmBuf, num16, this.subframeSize, num22, array, this.submodes[this.submodeID].CombGain);
}
if (this.enhanced)
{
Filters.Filter_mem2(this.frmBuf, num16, this.awk2, this.awk1, this.subframeSize, this.lpcSize, this.mem_sp, this.lpcSize);
Filters.Filter_mem2(this.frmBuf, num16, this.awk3, this.interp_qlpc, this.subframeSize, this.lpcSize, this.mem_sp, 0);
}
else
{
for (int i = 0; i < this.lpcSize; i++)
{
this.mem_sp[this.lpcSize + i] = 0f;
}
Filters.Iir_mem2(this.frmBuf, num16, this.interp_qlpc, this.frmBuf, num16, this.subframeSize, this.lpcSize, this.mem_sp);
}
}
xout[0] = this.frmBuf[this.frmIdx] + this.preemph * this.pre_mem;
for (int i = 1; i < this.frameSize; i++)
{
xout[i] = this.frmBuf[this.frmIdx + i] + this.preemph * xout[i - 1];
}
this.pre_mem = xout[this.frameSize - 1];
for (int i = 0; i < this.lpcSize; i++)
{
this.old_qlsp[i] = this.qlsp[i];
}
this.first = 0;
this.count_lost = 0;
this.last_pitch = num3;
this.last_pitch_gain = 0.25f * num5;
this.pitch_gain_buf[this.pitch_gain_buf_idx++] = this.last_pitch_gain;
if (this.pitch_gain_buf_idx > 2)
{
this.pitch_gain_buf_idx = 0;
}
this.last_ol_gain = num13;
return(0);
}
/// <summary>
/// Decode the given input bits.
/// </summary>
/// <returns>1 if a terminator was found, 0 if not.</returns>
/// <exception cref="InvalidFormatException">If there is an error detected in the data stream.</exception>
public virtual int Decode(Bits bits, float[] xout)
{
int i, sub, pitch, ol_pitch = 0, m;
float[] pitch_gain = new float[3];
float ol_gain = 0.0f, ol_pitch_coef = 0.0f;
int best_pitch = 40;
float best_pitch_gain = 0;
float pitch_average = 0;
if (bits == null && dtx_enabled != 0)
{
submodeID = 0;
}
else
{
/*
* If bits is NULL, consider the packet to be lost (what could we do
* anyway)
*/
if (bits == null)
{
DecodeLost(xout);
return(0);
}
/*
* Search for next narrowband block (handle requests, skip wideband
* blocks)
*/
do
{
if (bits.BitsRemaining() < 5)
{
return(-1);
}
if (bits.Unpack(1) != 0)
{ /*
* Skip wideband block (for
* compatibility)
*/
// Wideband
/* Get the sub-mode that was used */
m = bits.Unpack(NSpeex.SbCodec.SB_SUBMODE_BITS);
int advance = NSpeex.SbCodec.SB_FRAME_SIZE[m];
if (advance < 0)
{
throw new InvalidFormatException(
"Invalid sideband mode encountered (1st sideband): "
+ m);
// return -2;
}
advance -= (NSpeex.SbCodec.SB_SUBMODE_BITS + 1);
bits.Advance(advance);
if (bits.Unpack(1) != 0)
{ /*
* Skip ultra-wideband block
* (for compatibility)
*/
/* Get the sub-mode that was used */
m = bits.Unpack(NSpeex.SbCodec.SB_SUBMODE_BITS);
advance = NSpeex.SbCodec.SB_FRAME_SIZE[m];
if (advance < 0)
{
throw new InvalidFormatException(
"Invalid sideband mode encountered. (2nd sideband): "
+ m);
// return -2;
}
advance -= (NSpeex.SbCodec.SB_SUBMODE_BITS + 1);
bits.Advance(advance);
if (bits.Unpack(1) != 0)
{ /* Sanity check */
throw new InvalidFormatException(
"More than two sideband layers found");
// return -2;
}
}
// */
}
if (bits.BitsRemaining() < 4)
{
return(1);
}
/* Get the sub-mode that was used */
m = bits.Unpack(NSpeex.NbCodec.NB_SUBMODE_BITS);
if (m == 15)
{ /* We found a terminator */
return(1);
}
else if (m == 14)
{ /* Speex in-band request */
inband.SpeexInbandRequest(bits);
}
else if (m == 13)
{ /* User in-band request */
inband.UserInbandRequest(bits);
}
else if (m > 8)
{ /* Invalid mode */
throw new InvalidFormatException(
"Invalid mode encountered: " + m);
// return -2;
}
} while (m > 8);
submodeID = m;
}
/* Shift all buffers by one frame */
System.Array.Copy(frmBuf, frameSize, frmBuf, 0, bufSize
- frameSize);
System.Array.Copy(excBuf, frameSize, excBuf, 0, bufSize
- frameSize);
/* If null mode (no transmission), just set a couple things to zero */
if (submodes[submodeID] == null)
{
NSpeex.Filters.Bw_lpc(.93f, interp_qlpc, lpc, 10);
float innov_gain = 0;
for (i = 0; i < frameSize; i++)
{
innov_gain += innov[i] * innov[i];
}
innov_gain = (float)Math.Sqrt(innov_gain / frameSize);
for (i = excIdx; i < excIdx + frameSize; i++)
{
excBuf[i] = (float)(3 * innov_gain * (random.NextDouble() - .5f));
}
first = 1;
/* Final signal synthesis from excitation */
NSpeex.Filters.Iir_mem2(excBuf, excIdx, lpc, frmBuf, frmIdx,
frameSize, lpcSize, mem_sp);
xout[0] = frmBuf[frmIdx] + preemph * pre_mem;
for (i = 1; i < frameSize; i++)
{
xout[i] = frmBuf[frmIdx + i] + preemph * xout[i - 1];
}
pre_mem = xout[frameSize - 1];
count_lost = 0;
return(0);
}
/* Unquantize LSPs */
submodes[submodeID].LsqQuant.Unquant(qlsp, lpcSize, bits);
/* Damp memory if a frame was lost and the LSP changed too much */
if (count_lost != 0)
{
float lsp_dist = 0, fact;
for (i = 0; i < lpcSize; i++)
{
lsp_dist += Math.Abs(old_qlsp[i] - qlsp[i]);
}
fact = (float)(.6d * Math.Exp(-.2d * lsp_dist));
for (i = 0; i < 2 * lpcSize; i++)
{
mem_sp[i] *= fact;
}
}
/* Handle first frame and lost-packet case */
if (first != 0 || count_lost != 0)
{
for (i = 0; i < lpcSize; i++)
{
old_qlsp[i] = qlsp[i];
}
}
/* Get open-loop pitch estimation for low bit-rate pitch coding */
if (submodes[submodeID].LbrPitch != -1)
{
ol_pitch = min_pitch + bits.Unpack(7);
}
if (submodes[submodeID].ForcedPitchGain != 0)
{
int quant = bits.Unpack(4);
ol_pitch_coef = 0.066667f * quant;
}
/* Get global excitation gain */
int qe = bits.Unpack(5);
ol_gain = (float)Math.Exp(qe / 3.5d);
/* unpacks unused dtx bits */
if (submodeID == 1)
{
int extra = bits.Unpack(4);
if (extra == 15)
{
dtx_enabled = 1;
}
else
{
dtx_enabled = 0;
}
}
if (submodeID > 1)
{
dtx_enabled = 0;
}
/* Loop on subframes */
for (sub = 0; sub < nbSubframes; sub++)
{
int offset, spIdx, extIdx;
float tmp;
/* Offset relative to start of frame */
offset = subframeSize * sub;
/* Original signal */
spIdx = frmIdx + offset;
/* Excitation */
extIdx = excIdx + offset;
/* LSP interpolation (quantized and unquantized) */
tmp = (1.0f + sub) / nbSubframes;
for (i = 0; i < lpcSize; i++)
{
interp_qlsp[i] = (1 - tmp) * old_qlsp[i] + tmp * qlsp[i];
}
/* Make sure the LSP's are stable */
NSpeex.Lsp.Enforce_margin(interp_qlsp, lpcSize, .002f);
/* Compute interpolated LPCs (unquantized) */
for (i = 0; i < lpcSize; i++)
{
interp_qlsp[i] = (float)System.Math.Cos(interp_qlsp[i]);
}
m_lsp.Lsp2lpc(interp_qlsp, interp_qlpc, lpcSize);
/* Compute enhanced synthesis filter */
if (enhanced)
{
float r = .9f;
float k1, k2, k3;
k1 = submodes[submodeID].LpcEnhK1;
k2 = submodes[submodeID].LpcEnhK2;
k3 = (1 - (1 - r * k1) / (1 - r * k2)) / r;
NSpeex.Filters.Bw_lpc(k1, interp_qlpc, awk1, lpcSize);
NSpeex.Filters.Bw_lpc(k2, interp_qlpc, awk2, lpcSize);
NSpeex.Filters.Bw_lpc(k3, interp_qlpc, awk3, lpcSize);
}
/* Compute analysis filter at w=pi */
tmp = 1;
pi_gain[sub] = 0;
for (i = 0; i <= lpcSize; i++)
{
pi_gain[sub] += tmp * interp_qlpc[i];
tmp = -tmp;
}
/* Reset excitation */
for (i = 0; i < subframeSize; i++)
{
excBuf[extIdx + i] = 0;
}
/* Adaptive codebook contribution */
int pit_min, pit_max;
/* Handle pitch constraints if any */
if (submodes[submodeID].LbrPitch != -1)
{
int margin = submodes[submodeID].LbrPitch;
if (margin != 0)
{
pit_min = ol_pitch - margin + 1;
if (pit_min < min_pitch)
{
pit_min = min_pitch;
}
pit_max = ol_pitch + margin;
if (pit_max > max_pitch)
{
pit_max = max_pitch;
}
}
else
{
pit_min = pit_max = ol_pitch;
}
}
else
{
pit_min = min_pitch;
pit_max = max_pitch;
}
/* Pitch synthesis */
pitch = submodes[submodeID].Ltp.Unquant(excBuf, extIdx, pit_min,
ol_pitch_coef, subframeSize, pitch_gain, bits, count_lost,
offset, last_pitch_gain);
/* If we had lost frames, check energy of last received frame */
if (count_lost != 0 && ol_gain < last_ol_gain)
{
float fact_0 = ol_gain / (last_ol_gain + 1);
for (i = 0; i < subframeSize; i++)
{
excBuf[excIdx + i] *= fact_0;
}
}
tmp = Math.Abs(pitch_gain[0] + pitch_gain[1]
+ pitch_gain[2]);
tmp = Math.Abs(pitch_gain[1]);
if (pitch_gain[0] > 0)
{
tmp += pitch_gain[0];
}
else
{
tmp -= .5f * pitch_gain[0];
}
if (pitch_gain[2] > 0)
{
tmp += pitch_gain[2];
}
else
{
tmp -= .5f * pitch_gain[0];
}
pitch_average += tmp;
if (tmp > best_pitch_gain)
{
best_pitch = pitch;
best_pitch_gain = tmp;
}
/* Unquantize the innovation */
int q_energy, ivi = sub * subframeSize;
float ener;
for (i = ivi; i < ivi + subframeSize; i++)
{
innov[i] = 0.0f;
}
/* Decode sub-frame gain correction */
if (submodes[submodeID].HaveSubframeGain == 3)
{
q_energy = bits.Unpack(3);
ener = (float)(ol_gain * Math.Exp(NSpeex.NbCodec.exc_gain_quant_scal3[q_energy]));
}
else if (submodes[submodeID].HaveSubframeGain == 1)
{
q_energy = bits.Unpack(1);
ener = (float)(ol_gain * Math.Exp(NSpeex.NbCodec.exc_gain_quant_scal1[q_energy]));
}
else
{
ener = ol_gain;
}
if (submodes[submodeID].Innovation != null)
{
/* Fixed codebook contribution */
submodes[submodeID].Innovation.Unquantify(innov, ivi,
subframeSize, bits);
}
/* De-normalize innovation and update excitation */
for (i = ivi; i < ivi + subframeSize; i++)
{
innov[i] *= ener;
}
/* Vocoder mode */
if (submodeID == 1)
{
float g = ol_pitch_coef;
for (i = 0; i < subframeSize; i++)
{
excBuf[extIdx + i] = 0;
}
while (voc_offset < subframeSize)
{
if (voc_offset >= 0)
{
excBuf[extIdx + voc_offset] = (float)Math.Sqrt(1.0f * ol_pitch);
}
voc_offset += ol_pitch;
}
voc_offset -= subframeSize;
g = .5f + 2 * (g - .6f);
if (g < 0)
{
g = 0;
}
if (g > 1)
{
g = 1;
}
for (i = 0; i < subframeSize; i++)
{
float itmp = excBuf[extIdx + i];
excBuf[extIdx + i] = .8f * g * excBuf[extIdx + i] * ol_gain
+ .6f * g * voc_m1 * ol_gain + .5f * g
* innov[ivi + i] - .5f * g * voc_m2 + (1 - g)
* innov[ivi + i];
voc_m1 = itmp;
voc_m2 = innov[ivi + i];
voc_mean = .95f * voc_mean + .05f * excBuf[extIdx + i];
excBuf[extIdx + i] -= voc_mean;
}
}
else
{
for (i = 0; i < subframeSize; i++)
{
excBuf[extIdx + i] += innov[ivi + i];
}
}
/* Decode second codebook (only for some modes) */
if (submodes[submodeID].DoubleCodebook != 0)
{
for (i = 0; i < subframeSize; i++)
{
innov2[i] = 0;
}
submodes[submodeID].Innovation.Unquantify(innov2, 0, subframeSize,
bits);
for (i = 0; i < subframeSize; i++)
{
innov2[i] *= ener * (1 / 2.2f);
}
for (i = 0; i < subframeSize; i++)
{
excBuf[extIdx + i] += innov2[i];
}
}
for (i = 0; i < subframeSize; i++)
{
frmBuf[spIdx + i] = excBuf[extIdx + i];
}
/* Signal synthesis */
if (enhanced && submodes[submodeID].CombGain > 0)
{
filters.Comb_filter(excBuf, extIdx, frmBuf, spIdx,
subframeSize, pitch, pitch_gain,
submodes[submodeID].CombGain);
}
if (enhanced)
{
/* Use enhanced LPC filter */
NSpeex.Filters.Filter_mem2(frmBuf, spIdx, awk2, awk1,
subframeSize, lpcSize, mem_sp, lpcSize);
NSpeex.Filters.Filter_mem2(frmBuf, spIdx, awk3, interp_qlpc,
subframeSize, lpcSize, mem_sp, 0);
}
else
{
/* Use regular filter */
for (i = 0; i < lpcSize; i++)
{
mem_sp[lpcSize + i] = 0;
}
NSpeex.Filters.Iir_mem2(frmBuf, spIdx, interp_qlpc, frmBuf,
spIdx, subframeSize, lpcSize, mem_sp);
}
}
/* Copy output signal */
xout[0] = frmBuf[frmIdx] + preemph * pre_mem;
for (i = 1; i < frameSize; i++)
{
xout[i] = frmBuf[frmIdx + i] + preemph * xout[i - 1];
}
pre_mem = xout[frameSize - 1];
/* Store the LSPs for interpolation in the next frame */
for (i = 0; i < lpcSize; i++)
{
old_qlsp[i] = qlsp[i];
}
/* The next frame will not be the first (Duh!) */
first = 0;
count_lost = 0;
last_pitch = best_pitch;
last_pitch_gain = .25f * pitch_average;
pitch_gain_buf[pitch_gain_buf_idx++] = last_pitch_gain;
if (pitch_gain_buf_idx > 2) /* rollover */
{
pitch_gain_buf_idx = 0;
}
last_ol_gain = ol_gain;
return(0);
}