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after peak normalization before smoothing
+53
-4
+53
-4
src/ext/fft.c
+53
-4
src/ext/fft.c
···
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float fAmplification = 1.0f;
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bool bCreated = false;
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kiss_fft_cpx fftBuf[FFT_SIZE + 1];
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// float fFFTSmoothingFactor = 0.9f; // higher value, smoother FFT
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// static float fftDataSmoothed[FFT_SIZE];
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void OnReceiveFrames(ma_device* pDevice, void* pOutput, const void* pInput, ma_uint32 frameCount)
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{
···
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}
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//////////////////////////////////////////////////////////////////////////
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double tic_api_fft(tic_mem* memory, s32 freq) {
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static const float fPeakMinValue = 0.01f;
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static const float fPeakSmoothing = 0.995f;
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static float fPeakSmoothValue = 0.0f;
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double tic_api_fft(tic_mem* memory, s32 freq)
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{
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bool bPeakNormalization = true;
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if (bPeakNormalization) {
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float peakValue = fPeakMinValue;
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for (int i = 0; i < FFT_SIZE; i++) {
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float val = 2.0f * sqrtf(fftBuf[i].r * fftBuf[i].r + fftBuf[i].i * fftBuf[i].i);
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if (val > peakValue) {
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peakValue = val;
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}
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}
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if (peakValue > fPeakSmoothValue) {
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fPeakSmoothValue = peakValue;
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}
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if (peakValue < fPeakSmoothValue) {
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fPeakSmoothValue = fPeakSmoothValue * fPeakSmoothing + peakValue * (1 - fPeakSmoothing);
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}
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if (fPeakSmoothValue > 0.0f) {
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fAmplification = 1.0f / fPeakSmoothValue;
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if (freq < 10) {
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printf("freq: %d, fAmplification: %.2f\n", freq, fAmplification);
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}
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} else {
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fAmplification = 1.0f;
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}
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}
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u32 interval = FFT_SIZE / 256 / 2; // the 2 is to discard super high frequencies, they suck
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freq = freq * interval;
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freq = fmin(freq, FFT_SIZE);
···
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static const float scaling = 1.0f / (float)FFT_SIZE;
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float res = 0;
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for (int i = freq; i < freq + interval; ++i) {
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res += 2.0 * sqrtf(fftBuf[i].r * fftBuf[i].r + fftBuf[i].i * fftBuf[i].i) * scaling;
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res += 2.0f * sqrtf(fftBuf[i].r * fftBuf[i].r + fftBuf[i].i * fftBuf[i].i) * scaling * fAmplification;
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}
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if (freq < 10) {
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printf("freq: %d, res: %.2f\n", freq, res);
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}
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return res;
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}
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}
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// double tic_api_fft(tic_mem* memory, s32 freq)
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// {
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// u32 interval = FFT_SIZE / 256 / 2; // the 2 is to discard super high frequencies, they suck
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// freq = freq * interval;
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// freq = fmin(freq, FFT_SIZE);
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// freq = fmax(freq, 0);
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// static const float scaling = 1.0f / (float)FFT_SIZE;
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// float res = 0;
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// for (int i = freq; i < freq + interval; ++i) {
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// res += 2.0 * sqrtf(fftBuf[i].r * fftBuf[i].r + fftBuf[i].i * fftBuf[i].i) * scaling;
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// }
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// return res;
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// }