语音信号数字处理研究

//--------------------------------------------------------------------------- #include <vcl.h> #pragma hdrstop #include <math> #include "SpectrumThread.h" #pragma package(smart_init) const double PI=3.14159265; //--------------------------------------------------------------------------- __fastcall SpectrumThread::SpectrumThread(bool CreateSuspended, TPaintBox *in, int ic) : TThread(CreateSuspended) { count=ic; view=in; data=new short[ic * 2]; WaveR=new double[ic]; WaveI=new double[ic]; busy=false; } //--------------------------------------------------------------------------- __fastcall SpectrumThread::~SpectrumThread(void) { delete[] data; delete[] WaveR; delete[] WaveI; } //--------------------------------------------------------------------------- void SpectrumThread::Process(short *idata) { if(!busy) { memcpy(data, idata, 2 * count * sizeof(short)); Resume(); } } //--------------------------------------------------------------------------- void SpectrumThread::SetMousePoint(int x, int y) { if(!busy) { point.x=x; point.y=y; } } //--------------------------------------------------------------------------- void __fastcall SpectrumThread::Execute(void) { //---- Place thread code here ---- while(!Terminated) { FillBuffer(); } } //--------------------------------------------------------------------------- void __fastcall SpectrumThread::FillBuffer(void) { long zerolevel=view->ClientHeight - 30; int i, dx, freq; double ts=static_cast<double>(view->ClientWidth) / static_cast<double>(count) * 2; busy=true; view->Canvas->Lock(); view->Canvas->Brush->Color=clBlack; view->Canvas->Pen->Color=clWhite; view->Canvas->Rectangle(0, 0, view->ClientWidth, view->ClientHeight); view->Canvas->Pen->Color=clYellow; view->Canvas->MoveTo(0, zerolevel); view->Canvas->LineTo(view->ClientWidth, zerolevel); dx=view->ClientWidth / 22; for(long i=dx; i < view->ClientWidth - dx; i+=dx) { view->Canvas->TextOutA(i - 12, zerolevel + 2, IntToStr(i / dx) + "kHz"); } freq=point.x * 22050 / view->ClientWidth; view->Canvas->TextOutA(view->ClientWidth - 50, 10, IntToStr(freq) + "Hz"); memset(WaveI, 0, count * sizeof(double)); for(i=0; i < count; i++) { WaveR[i]=data[i * 2]; } FFT(WaveR, WaveI, count, 1); view->Canvas->Pen->Color=clAqua; view->Canvas->MoveTo(0, zerolevel - sqrt(WaveR[0] * WaveR[0] + WaveI[0] * WaveI[0]) / count * 2); for(i=1; i < count / 2; i++) { view->Canvas->LineTo(i * ts, zerolevel - sqrt(WaveR[i] * WaveR[i] + WaveI[i] * WaveI[i]) / count * 2); } memset(WaveI, 0, count * sizeof(double)); for(i=0; i < count; i++) { WaveR[i]=data[i * 2 + 1]; } FFT(WaveR, WaveI, count, 1); view->Canvas->Pen->Color=clRed; view->Canvas->MoveTo(0, zerolevel - sqrt(WaveR[0] * WaveR[0] + WaveI[0] * WaveI[0]) / count * 2); for(i=1; i < count / 2; i++) { view->Canvas->LineTo(i * ts, zerolevel - sqrt(WaveR[i] * WaveR[i] + WaveI[i] * WaveI[i]) / count * 2); } view->Canvas->Unlock(); busy=false; Suspend(); } //--------------------------------------------------------------------------- void __fastcall SpectrumThread::fft1(double *br, double *bi, int il, const double *st, const double *ct) { //the size of br,bi should be equal to il. //and size of st and ct no less than il. int is=il >> 1; int mpx=0; int ic=1; int ia; while(is) { is>>=1; mpx++; } is=il; for(ia=1; ia <= mpx; ia++) { int ib; int ka=0; is>>=1; for(ib=1; ib <= ic; ib++) { int in=1; int k; for(k=1; k <= is; k++) { int j1=ka + k; int j2=j1 + is; double xr=br[j1]; double xi=bi[j1]; double yr=br[j2]; double yi=bi[j2]; br[j1]=xr + yr; bi[j1]=xi + yi; xr-=yr; xi-=yi; br[j2]=xr * ct[in] - xi * st[in]; bi[j2]=xr * st[in] + xi * ct[in]; in+=ic; } ka+=is << 1; } ic<<=1; } } /* */ void __fastcall SpectrumThread::binrv(double *bc, int il, const int *lb) { int is=il - 1; int i; for(i=2; i <= is; i++) { int ig=lb[i]; if(ig <= i) continue; double xx=bc[i]; bc[i]=bc[ig]; bc[ig]=xx; } } /* */ void __fastcall SpectrumThread::brtab(int *lbr, int il) { int is=il >> 1; int mpx=0; while(is) { is>>=1; mpx++; } int ln; for(ln=1; ln <= il; ln++) { int j1=ln - 1; int ibord=0; for(int k=1; k <= mpx; k++) { int j2=j1 >> 1; ibord=ibord * 2 + (j1 - 2 * j2); j1=j2; } lbr[ln]=ibord + 1; } } /* */ void __fastcall SpectrumThread::cstab(double *st, double *ct, int il, int ity) { double yy; yy= -PI * 2.0 / il; if(ity < 0) yy= -yy; int l; double ang=0.0; for(l=1; l <= il; l++) { st[l]=sin(ang); ct[l]=cos(ang); ang+=yy; } } /* */ void __fastcall SpectrumThread::FFT(double *br, double *bi, int n, int ity) //ity>0 forward ,ity<0 backward //n=pow(2,m); //Here br and bi start from 0. { double *ct, *st; int *il; if(n <= 0) return; double invsqrtn=1.0 / sqrt(n); ct= (double *)malloc(sizeof(double) * n) - 1; st= (double *)malloc(sizeof(double) * n) - 1; cstab(st, ct, n, ity); il= (int *)malloc(sizeof(int) * n) - 1; brtab(il, n); fft1(br - 1, bi - 1, n, st, ct); binrv(br - 1, n, il); binrv(bi - 1, n, il); for(int i=0; i < n; i++) { br[i]*=invsqrtn; bi[i]*=invsqrtn; } free(il + 1); free(ct + 1); free(st + 1); }