SharpTalkTTS
Released
FormantSynth.cs
#nullable enable
using System;
namespace SharpTalk
{
public class FormantSynth
{
public const int KMaxBandWidth = 1225;
public const int KPrecision = 13;
public const int KNoiseLen = 2048;
public const int KOnePtOh = 0x2000;
public const int KNoiseGain = 3200;
public const int KSampFrameLen = 112;
// Filter coefficients
private short Acoeff1, Bcoeff1, Ccoeff1;
private short Acoeff2, Bcoeff2, Ccoeff2;
private short Acoeff3, Bcoeff3, Ccoeff3;
private short Acoeff4, Bcoeff4, Ccoeff4;
private short Acoeff4p, Bcoeff4p, Ccoeff4p;
private short Acoeff5, Bcoeff5, Ccoeff5;
private short Acoeff6, Bcoeff6, Ccoeff6;
private short AcoeffNZ, BcoeffNZ, CcoeffNZ;
private short AcoeffNP, BcoeffNP, CcoeffNP;
// IIR delay taps
private short Na1, Nb1;
private short Na2, Nb2;
private short Na3, Nb3;
private short Na4, Nb4;
private short Na5, Nb5;
private short Na6, Nb6;
private short Na2a, Nb2a;
private short Na3a, Nb3a;
private short Na4a, Nb4a;
private short NaNZ, NbNZ;
private short NaNP, NbNP;
// Parallel bank input gains
private short amp2, amp3, amp4, amp5, amp6, ab;
// State
private int glotIndex;
private int noiseIndex;
private short lastnSamp;
private long curAmp_Full;
private short curAmp;
private short lastSample;
private long ampStep;
private long lastAmp;
// Glottal excitation
private int glotInc;
private int glotInc1;
private int glotIndex1;
private short[] voiceWaveform = new short[256];
private short[] voiceWaveform1 = new short[256];
public short VoiceChorus { get; set; }
public int GlotType { get; set; } = KUseHarm;
public byte[]? SampleWave { get; set; }
public int SampleInc { get; set; }
public int SampleIndex { get; set; }
public const int KUseHarm = 0;
public const int KUseSnd = 1;
public const int KUseSyncSnd = 2;
// Noise excitation
private byte[] noiseWave = Tables.NoiseWave;
private byte[] bandNoise = Tables.BandNoise;
private byte[] hpNoise = Tables.HPNoise;
// Gain
private short Av, Af;
private short wavesampleGain;
private short voiceNoiseGain;
private short reverbDepth;
private int reverbDelay;
private bool addReverb;
private bool hfEmph = true;
private short speechVolume = 256;
private short setNoiseGain = 3200;
private short voiceF1Gain, voiceF2Gain, voiceF3Gain;
private short nasalAmt;
private short fNP;
private short bNP;
private short breathGain;
private short breathCycle;
private byte[] breathWave;
private short voiceMinBW = 50;
// Parallel F-bank params (from voiceData)
private short f4_Par;
private short bw4_Par;
private short f5_Par;
private short bw5_Par;
private short f6_Par;
private short bw6_Par;
private short voice_F4_Freq;
private short voice_F4_BW;
public FormantSynth()
{
maxRvbDelay = 4096;
delayBuffer = new short[maxRvbDelay];
breathWave = Tables.BandNoise;
tapBuffer[0] = 404;
tapBuffer[1] = 1058;
tapBuffer[2] = 1362;
tapBuffer[3] = 2318;
tapBuffer[4] = 2909;
tapBuffer[5] = 3723;
tapBuffer[6] = 4030;
tapBuffer[7] = 4096;
}
public void SetVoice(short nGain, bool bit16, short f4_Freq, short f4_BW, short f4p_Freq, short bw4p_BW, short f5p_Freq, short bw5p_BW, short f6p_Freq, short bw6p_BW, short nasal_Base, short nasal_BW, short aGain = 0, short aCycle = 192)
{
breathGain = (short)((aGain * KNoiseGain) / 100);
breathCycle = aCycle;
long tempLong = nGain;
voiceNoiseGain = (short)MRatio(tempLong, 100, KPrecision);
if (bit16)
{
voiceNoiseGain = (short)MMul2(voiceNoiseGain, 0xCCCC, 16);
}
setNoiseGain = voiceNoiseGain;
voice_F4_Freq = HzToPitch(f4_Freq);
voice_F4_BW = f4_BW;
f4_Par = HzToPitch(f4p_Freq);
bw4_Par = bw4p_BW;
f5_Par = HzToPitch(f5p_Freq);
bw5_Par = bw5p_BW;
f6_Par = HzToPitch(f6p_Freq);
bw6_Par = bw6p_BW;
fNP = HzToPitch(nasal_Base);
bNP = nasal_BW;
InitFixedFormants();
}
private void InitFixedFormants()
{
Calc_Pole_Coefficients(out Acoeff4, out Bcoeff4, out Ccoeff4, voice_F4_Freq, voice_F4_BW);
Calc_Pole_Coefficients(out Acoeff4p, out Bcoeff4p, out Ccoeff4p, f4_Par, bw4_Par);
Acoeff4p = (short)MMul2(Acoeff4p, KNoiseGain, KPrecision);
Calc_Pole_Coefficients(out Acoeff5, out Bcoeff5, out Ccoeff5, f5_Par, bw5_Par);
Acoeff5 = (short)MMul2(Acoeff5, KNoiseGain, KPrecision);
Calc_Pole_Coefficients(out Acoeff6, out Bcoeff6, out Ccoeff6, f6_Par, bw6_Par);
Acoeff6 = (short)MMul2(Acoeff6, KNoiseGain, KPrecision);
Calc_Pole_Coefficients(out AcoeffNP, out BcoeffNP, out CcoeffNP, fNP, bNP);
}
// Reverb state
private const int KNumOfTaps = 8;
private short[] tapBuffer = new short[KNumOfTaps];
private short[] delayBuffer;
private int maxRvbDelay;
private int delay_Index;
private long lastRevbSample;
private static int MMul2(long x, long y, int s)
{
return (int)((x * y) >> s);
}
private static int MRatio(long x, long y, int s)
{
return (int)((x << s) / y);
}
private static int MUnScale(long x, int s)
{
return (int)(x >> s);
}
private static short MDiv(int x, int y, int s)
{
return (short)(x >> s);
}
public void Calc_Pole_Coefficients(out short Acoeff, out short Bcoeff, out short Ccoeff, short pitch, short bandWidth, int voiceMinBW = 50)
{
if (bandWidth > KMaxBandWidth) bandWidth = (short)KMaxBandWidth;
if (bandWidth < voiceMinBW) bandWidth = (short)voiceMinBW;
if (pitch < 256) pitch = 256;
if (pitch >= 256 + Tables.CosTbl.Length) pitch = (short)(256 + Tables.CosTbl.Length - 1);
int bwIndex = (bandWidth - 50) / 5;
Ccoeff = Tables.CcoeffTbl[bwIndex];
short cosVal = Tables.CosTbl[pitch - 256];
Bcoeff = (short)MMul2(Tables.BcoeffTbl[bwIndex], cosVal, KPrecision - 1);
Acoeff = (short)(KOnePtOh - Bcoeff - Ccoeff);
}
public void Calc_Zero_Coefficients(out short Acoeff, out short Bcoeff, out short Ccoeff, short pitch, short bandWidth)
{
if (bandWidth > KMaxBandWidth) bandWidth = (short)KMaxBandWidth;
if (pitch < 256) pitch = 256;
if (pitch >= 256 + Tables.CosTbl.Length) pitch = (short)(256 + Tables.CosTbl.Length - 1);
int bwIndex = (bandWidth - 50) / 5;
Ccoeff = Tables.CcoeffTbl[bwIndex];
short cosVal = Tables.CosTbl[pitch - 256];
Bcoeff = (short)MMul2(Tables.BcoeffTbl[bwIndex], cosVal, KPrecision - 1);
Bcoeff = (short)(-Bcoeff);
Ccoeff = (short)(-Ccoeff);
Acoeff = (short)(KOnePtOh + Bcoeff + Ccoeff);
}
public void InvDFT(short[] vWave, short[] vWave1, short vGain)
{
if (vWave == null || vWave1 == null)
{
for (int j = 0; j < 256; j++)
{
voiceWaveform[j] = 0;
voiceWaveform1[j] = 0;
}
return;
}
int voiceWaveGain = MRatio(vGain, 200, 16);
for (int j = 0; j < 256; j++)
{
voiceWaveform[j] = 0;
voiceWaveform1[j] = 0;
}
for (int i = 0; i < 48; i++)
{
short amp = (short)MMul2(vWave[i], voiceWaveGain, 16);
short amp1 = (short)MMul2(vWave1[i], voiceWaveGain, 16);
int sIndex = 0;
for (int j = 0; j < 256; j++)
{
short sine = Tables.SineWave15[sIndex];
voiceWaveform[j] = (short)(voiceWaveform[j] + (short)MMul2(amp, sine, 16));
voiceWaveform1[j] = (short)(voiceWaveform1[j] + (short)MMul2(amp1, sine, 16));
sIndex = (sIndex + i) & 0xFF;
}
}
int max = 0;
int max1 = 0;
for (int j = 0; j < 256; j++)
{
if (Math.Abs(voiceWaveform[j]) > max) max = Math.Abs(voiceWaveform[j]);
if (Math.Abs(voiceWaveform1[j]) > max1) max1 = Math.Abs(voiceWaveform1[j]);
}
if (max1 > 0)
{
int max2 = MRatio(max, max1, 16);
for (int j = 0; j < 256; j++)
{
voiceWaveform1[j] = (short)MMul2(voiceWaveform1[j], max2, 16);
}
}
}
public void SynthesizeFrame(Frame frame, short[] outputBuffer, int offset)
{
if ((curAmp == 0) && (Af == 0))
{
glotIndex = 0;
glotIndex1 = 0;
Na1 = Nb1 = Na2 = Nb2 = Na3 = Nb3 = Na4 = Nb4 = 0;
NaNP = NbNP = NaNZ = NbNZ = 0;
lastAmp = 0;
}
Calc_Pole_Coefficients(out Acoeff1, out Bcoeff1, out Ccoeff1, (short)(frame.F1 + voiceF1Gain), frame.Bw1);
Calc_Pole_Coefficients(out Acoeff2, out Bcoeff2, out Ccoeff2, (short)(frame.F2 + voiceF2Gain), frame.Bw2);
Calc_Pole_Coefficients(out Acoeff3, out Bcoeff3, out Ccoeff3, (short)(frame.F3 + voiceF3Gain), frame.Bw3);
bool noNasal;
int nGain = 0;
if (frame.FNZ != fNP)
{
noNasal = false;
Calc_Zero_Coefficients(out AcoeffNZ, out BcoeffNZ, out CcoeffNZ, (short)(frame.FNZ + nasalAmt), bNP);
nGain = MRatio(AcoeffNP, AcoeffNZ, 16);
}
else
{
noNasal = true;
}
bool ampBank = false;
short rawAv = frame.Av;
Av = (short)(rawAv * speechVolume);
Af = (short)((frame.Af * speechVolume) << 2);
ab = (short)(frame.AB * speechVolume);
if (Af > 0 || ab > 0) ampBank = true;
short totalBreathGain = (short)MMul2(breathGain, Av, KPrecision);
short Acoeff2q = 0, Acoeff3q = 0, Acoeff4q = 0, Acoeff5q = 0, Acoeff6q = 0;
if (frame.A2 > 0) { amp2 = (short)(frame.A2 << (KPrecision - 5)); Acoeff2q = (short)MMul2(Acoeff2, amp2, KPrecision); ampBank = true; }
else { amp2 = 0; Nb2a = 0; Na2a = 0; }
if (frame.A3 > 0) { amp3 = (short)(frame.A3 << (KPrecision - 5)); Acoeff3q = (short)MMul2(Acoeff3, amp3, KPrecision); ampBank = true; }
else { amp3 = 0; Nb3a = 0; Na3a = 0; }
if (frame.A4 > 0) { amp4 = (short)(frame.A4 << (KPrecision - 5)); Acoeff4q = (short)MMul2(Acoeff4p, amp4, KPrecision); ampBank = true; }
else { amp4 = 0; Nb4a = 0; Na4a = 0; }
if (frame.A5 > 0) { amp5 = (short)(frame.A5 << (KPrecision - 5)); Acoeff5q = (short)MMul2(Acoeff5, amp5, KPrecision); ampBank = true; }
else { amp5 = 0; Nb5 = 0; Na5 = 0; }
if (frame.A6 > 0) { amp6 = (short)(frame.A6 << (KPrecision - 5)); Acoeff6q = (short)MMul2(Acoeff6, amp6, KPrecision); ampBank = true; }
else { amp6 = 0; Nb6 = 0; Na6 = 0; }
glotInc = Tables.TopOctave[frame.F0 & 0xFF] >> (3 - (frame.F0 >> 8));
if (VoiceChorus != 0)
{
int curF0Pitch = frame.F0 + VoiceChorus;
if (curF0Pitch < 0) curF0Pitch = 0;
glotInc1 = Tables.TopOctave[curF0Pitch & 0xFF] >> (3 - (curF0Pitch >> 8));
}
const int kAmpStepRes = 16;
ampStep = (((long)Av << kAmpStepRes) - lastAmp) >> 3;
curAmp_Full = lastAmp;
lastAmp = ((long)Av << kAmpStepRes);
int local_ampCtr = 0;
for (int sampCtr = (KSampFrameLen / 2) - 1; sampCtr >= 0; --sampCtr)
{
if (local_ampCtr < 8) { curAmp_Full += ampStep; curAmp = (short)(curAmp_Full >> kAmpStepRes); local_ampCtr++; }
else { curAmp = Av; }
int sourceC = 0, SampV = 0, sourceP = 0, SampAB = 0, Samp2 = 0, Samp3 = 0, Samp4 = 0, Samp5 = 0, Samp6 = 0;
if (curAmp > 0 || ampBank || totalBreathGain > 0)
{
noiseIndex = (noiseIndex + 1) & (KNoiseLen - 1);
if (curAmp > 0)
{
short vPulse;
if (GlotType == KUseHarm)
{
glotIndex = (glotInc + glotIndex) & 0xFFFFFF;
vPulse = voiceWaveform[glotIndex >> 16];
if (VoiceChorus != 0)
{
glotIndex1 = (glotInc1 + glotIndex1) & 0xFFFFFF;
vPulse = MDiv(vPulse + voiceWaveform1[glotIndex1 >> 16], 2, 1);
}
}
else
{
glotIndex = (glotInc + glotIndex) & 0xFFFFFF;
if (SampleWave != null)
{
SampleIndex = (SampleInc + SampleIndex) & 0xFFFFFF;
vPulse = (short)(SampleWave[SampleIndex >> 16] - 128);
vPulse = (short)MMul2(vPulse, wavesampleGain, KPrecision);
}
else vPulse = 0;
}
sourceC = MMul2(vPulse, curAmp, KPrecision);
}
else
{
// No voicing, but still advance glotIndex for breathCycle gating
if (totalBreathGain > 0) glotIndex = (glotInc + glotIndex) & 0xFFFFFF;
else { lastnSamp = 0; glotIndex = 0; glotIndex1 = 0; }
sourceC = 0;
}
// Breath (aspiration) source — injected when cycle position exceeds breathCycle
if (totalBreathGain > 0 && (glotIndex >> 16) > breathCycle)
sourceC += MMul2((short)(breathWave[noiseIndex] - 128), totalBreathGain, KPrecision - 2);
if (curAmp > 0 || Af > 0 || totalBreathGain > 0)
{
sourceC += MMul2((short)(bandNoise[noiseIndex] - 128), Af, KPrecision);
if (noNasal) SampV = sourceC;
else
{
SampV = sourceC + MUnScale(((long)BcoeffNZ * NaNZ) + ((long)CcoeffNZ * NbNZ), KPrecision);
NbNZ = NaNZ; NaNZ = (short)sourceC;
SampV = MMul2(SampV, nGain, 16);
SampV = SampV + MUnScale(((long)BcoeffNP * NaNP) + ((long)CcoeffNP * NbNP), KPrecision);
NbNP = NaNP; NaNP = (short)SampV;
}
SampV = MUnScale(((long)Acoeff1 * SampV) + ((long)Bcoeff1 * Na1) + ((long)Ccoeff1 * Nb1), KPrecision);
Nb1 = Na1; Na1 = (short)SampV;
SampV = MUnScale(((long)Acoeff2 * SampV) + ((long)Bcoeff2 * Na2) + ((long)Ccoeff2 * Nb2), KPrecision);
Nb2 = Na2; Na2 = (short)SampV;
SampV = MUnScale(((long)Acoeff3 * SampV) + ((long)Bcoeff3 * Na3) + ((long)Ccoeff3 * Nb3), KPrecision);
Nb3 = Na3; Na3 = (short)SampV;
SampV = MUnScale(((long)Acoeff4 * SampV) + ((long)Bcoeff4 * Na4) + ((long)Ccoeff4 * Nb4), KPrecision);
Nb4 = Na4; Na4 = (short)SampV;
}
sourceP = MMul2((short)(noiseWave[noiseIndex] - 128), voiceNoiseGain, KPrecision);
if (ab > 0) SampAB = MMul2(sourceP, ab, KPrecision - 1);
if (amp2 > 0) { Samp2 = MUnScale(((long)Acoeff2q * sourceP) + ((long)Bcoeff2 * Na2a) + ((long)Ccoeff2 * Nb2a), KPrecision); Nb2a = Na2a; Na2a = (short)Samp2; }
if (amp3 > 0) { Samp3 = MUnScale(((long)Acoeff3q * sourceP) + ((long)Bcoeff3 * Na3a) + ((long)Ccoeff3 * Nb3a), KPrecision); Nb3a = Na3a; Na3a = (short)Samp3; }
if (amp4 > 0) { Samp4 = MUnScale(((long)Acoeff4q * sourceP) + ((long)Bcoeff4p * Na4a) + ((long)Ccoeff4p * Nb4a), KPrecision); Nb4a = Na4a; Na4a = (short)Samp4; }
if (amp5 > 0) { Samp5 = MUnScale(((long)Acoeff5q * sourceP) + ((long)Bcoeff5 * Na5) + ((long)Ccoeff5 * Nb5), KPrecision); Nb5 = Na5; Na5 = (short)Samp5; }
if (amp6 > 0) { Samp6 = MUnScale(((long)Acoeff6q * sourceP) + ((long)Bcoeff6 * Na6) + ((long)Ccoeff6 * Nb6), KPrecision); Nb6 = Na6; Na6 = (short)Samp6; }
int nSamp = SampV + (SampAB - Samp3 + Samp4 - Samp5 + Samp6 - Samp2);
if (hfEmph)
{
nSamp += (nSamp >> 2);
int tSamp = nSamp - (lastSample - (lastSample >> 2));
lastSample = (short)nSamp;
nSamp = tSamp + (nSamp >> 1);
}
if (nSamp > 8191) nSamp = 8191; else if (nSamp < -8191) nSamp = -8191;
outputBuffer[offset++] = (short)((((nSamp - lastnSamp) >> 1) + lastnSamp) << 2);
outputBuffer[offset++] = (short)(nSamp << 2);
lastnSamp = (short)nSamp;
}
else
{
lastnSamp = 0; glotIndex = 0; glotIndex1 = 0;
outputBuffer[offset++] = 0; outputBuffer[offset++] = 0;
}
}
}
public static short HzToPitch(short hz)
{
const int ratioK = 2621;
int fk, freq;
if (hz <= 0) return 0;
if (hz < 100) { freq = hz << 3; fk = 0x0; }
else if (hz < 200) { freq = hz << 2; fk = 0x100; }
else if (hz < 400) { freq = hz << 1; fk = 0x200; }
else if (hz < 800) { freq = hz; fk = 0x300; }
else if (hz < 1600) { freq = hz >> 1; fk = 0x400; }
else if (hz < 3200) { freq = hz >> 2; fk = 0x500; }
else { freq = hz >> 3; fk = 0x600; }
int ratio = ((freq - 400) * ratioK) >> 11;
if (ratio < 0) ratio = 0;
if (ratio >= Tables.logOf2Tbl.Length) ratio = Tables.logOf2Tbl.Length - 1;
return (short)(Tables.logOf2Tbl[ratio] + fk);
}
public static short PitchToHz(short pitch)
{
int freq = (Tables.OctFreqTbl[(pitch & 0xF00) >> 8] * Tables.ExpOf2Tbl[pitch & 0xFF]) >> 15;
return (short)freq;
}
}
public struct Frame
{
public short Av;
public short Af;
public short F0;
public short F1;
public short F2;
public short F3;
public short A2;
public short A3;
public short A4;
public short A5;
public short A6;
public short FNZ;
public short AB;
public short Bw1;
public short Bw2;
public short Bw3;
public short PhonEdge;
public long Marker;
}
} // namespace