public void UserInbandRequest(Bits bits)
{
int num = bits.Unpack(4);
bits.Advance(5 + 8 * num);
}
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_16C;
}
}
return(-1);
}
IL_16C:
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);
}
public void SpeexInbandRequest(Bits bits)
{
switch (bits.Unpack(4))
{
case 0:
bits.Advance(1);
return;
case 1:
bits.Advance(1);
return;
case 2:
bits.Advance(4);
return;
case 3:
bits.Advance(4);
return;
case 4:
bits.Advance(4);
return;
case 5:
bits.Advance(4);
return;
case 6:
bits.Advance(4);
return;
case 7:
bits.Advance(4);
return;
case 8:
bits.Advance(8);
return;
case 9:
this.stereo.Init(bits);
return;
case 10:
bits.Advance(16);
return;
case 11:
bits.Advance(16);
return;
case 12:
bits.Advance(32);
return;
case 13:
bits.Advance(32);
return;
case 14:
bits.Advance(64);
return;
case 15:
bits.Advance(64);
return;
default:
return;
}
}
