Boolean FFTBufferManager::ComputeFFT(int32_t *outFFTData, float_t *outMajorPitch) { if (HasNewAudioData()) { SpectrumAnalysisProcess(mSpectrumAnalysis, mAudioBuffer, outFFTData, outMajorPitch, true); OSAtomicDecrement32Barrier(&mHasAudioData); OSAtomicIncrement32Barrier(&mNeedsAudioData); mAudioBufferCurrentIndex = 0; return true; } else if (mNeedsAudioData == 0) OSAtomicIncrement32Barrier(&mNeedsAudioData); return false; }
Boolean FFTBufferManager::ComputeFFT(int32_t *outFFTData) { if (HasNewAudioData()) { // for(int i=0;i<mFFTLength;i++) // { // if(mAudioBuffer[i]>0.15) // printf("%f\n",mAudioBuffer[i]); // } //Generate a split complex vector from the real data # define NOISE_FILTER 0.01; for(int i=0;i<4096;i++) { //DENOISE if(mAudioBuffer[i]>0) { mAudioBuffer[i] -= NOISE_FILTER; if(mAudioBuffer[i] < 0) { mAudioBuffer[i] = 0; } } else if(mAudioBuffer[i]<0) { mAudioBuffer[i] += NOISE_FILTER; if(mAudioBuffer[i]>0) { mAudioBuffer[i] = 0; } } else { mAudioBuffer[i] = 0; } } vDSP_ctoz((COMPLEX *)mAudioBuffer, 2, &mDspSplitComplex, 1, mFFTLength); //Take the fft and scale appropriately vDSP_fft_zrip(mSpectrumAnalysis, &mDspSplitComplex, 1, mLog2N, kFFTDirection_Forward); vDSP_vsmul(mDspSplitComplex.realp, 1, &mFFTNormFactor, mDspSplitComplex.realp, 1, mFFTLength); vDSP_vsmul(mDspSplitComplex.imagp, 1, &mFFTNormFactor, mDspSplitComplex.imagp, 1, mFFTLength); //Zero out the nyquist value mDspSplitComplex.imagp[0] = 0.0; //Convert the fft data to dB Float32 tmpData[mFFTLength]; vDSP_zvmags(&mDspSplitComplex, 1, tmpData, 1, mFFTLength); //In order to avoid taking log10 of zero, an adjusting factor is added in to make the minimum value equal -128dB vDSP_vsadd(tmpData, 1, &mAdjust0DB, tmpData, 1, mFFTLength); Float32 one = 1; vDSP_vdbcon(tmpData, 1, &one, tmpData, 1, mFFTLength, 0); //Convert floating point data to integer (Q7.24) vDSP_vsmul(tmpData, 1, &m24BitFracScale, tmpData, 1, mFFTLength); for(UInt32 i=0; i<mFFTLength; ++i) outFFTData[i] = (SInt32) tmpData[i]; for(int i=0;i<mFFTLength/4;i++) { printf("%i:::%i\n",i,outFFTData[i]/16777216+120); } OSAtomicDecrement32Barrier(&mHasAudioData); OSAtomicIncrement32Barrier(&mNeedsAudioData); mAudioBufferCurrentIndex = 0; return true; } else if (mNeedsAudioData == 0) OSAtomicIncrement32Barrier(&mNeedsAudioData); return false; }