Array<T,N> convolutionWithFFT(
const Array<T,N>& A,
const Array<T,N>& B
){
TinyVector<int,N> a = A.length();
TinyVector<int,N> b = B.length();
Array<T,N> padA(a+b);
Array<T,N> padB(a+b);
padAround(A,padA);
padAround(B,padB);
Array<std::complex<T>,N> Afft = forwardFFT(padA);
Array<std::complex<T>,N> Bfft = forwardFFT(padB);
Afft *= Bfft;
Array<T,N> C = inverseFFT(Afft);
TinyVector<int, N> c = (a+b+1)/2;
return circularShift(C,c);
}
int main(void) //main program
{
ex_sask_init( ); //init sask
ADCChannelInit (pADCChannelHandle,adcBuffer); //init audio input handler
OCPWMInit (pOCPWMHandle,ocPWMBuffer);
ADCChannelStart (pADCChannelHandle); //start audio input handler
OCPWMStart (pOCPWMHandle);
while(1)
{
if(state==0) //Program is in READY state
{
state=0; //set state to 0[READY]
state=displayState(STATE_READY); //call ready state function and read new state back
turnOffAll(); //turn off all LEDs when leaving ready state
}
else if(state==1) //Program is in READ state
{
while(ADCChannelIsBusy(pADCChannelHandle)); //read audio input
ADCChannelRead (pADCChannelHandle,AudioIn,FFT_FRAME_SIZE);
state=3;
}
else if(state==3) //Program is in ANALZYE state
{
int i=0;
analysingState(1);
FFT(&AudioIn, &FFTcompResults); //FFT function used on audio input, using FFT_FRAME_SIZE and returning the results in FFTcompResults
analysingState(2);
generateAuralisation(&AuralisationWorkSpace, &FFTcompResults);
analysingState(3);
for(i=0;i<FFT_FRAME_SIZE;i++)
{
inverseFFT(AudioOut[i], AuralisationWorkSpace[i]);
}
state=displayState(STATE_ANALYSE); //analising finished
}
else if(state==4) //Program is in PLAY BACK state
{
int x;
for(x=0;x<FFT_FRAME_SIZE;x++)
{
while(OCPWMIsBusy(pOCPWMHandle));
OCPWMWrite (pOCPWMHandle,AudioOut[x],FFT_FRAME_SIZE);
playbackState();
}
OCPWMStop (pOCPWMHandle); //stop audio output
state=0;
}
else //Program is in ERROR state
{
state=displayState(STATE_ERROR); //show error state on LEDs and read new state
}
}
}
