28 lines
720 B
C
28 lines
720 B
C
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#pragma once
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#include "stdafx.h"
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#include <assert.h>
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#include <numeric>
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class LowPassFilter
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{
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private:
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uint8_t _prevSampleCounter = 0;
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int16_t _prevSamples[10] = { 0,0,0,0,0,0,0,0,0,0};
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public:
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void ApplyFilter(int16_t *buffer, size_t sampleCount, int strength, double volume = 1.0f)
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{
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assert(strength <= 10);
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for(int i = 0; i < sampleCount; i++) {
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if(strength > 0) {
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int32_t sum = std::accumulate(&_prevSamples[0], &_prevSamples[strength], 0);
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buffer[i] = (int16_t)((sum + buffer[i]) / (strength + 1) * volume);
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_prevSamples[_prevSampleCounter] = buffer[i];
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_prevSampleCounter = (_prevSampleCounter + 1) % strength;
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} else {
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buffer[i] = (int16_t)(buffer[i] * volume);
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}
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}
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}
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};
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