PeakDetection.tpp

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#pragma once
 
template <size_t sampleSize>
PeakDetection<sampleSize>::PeakDetection(uint8_t lag, float threshold, float influence) {
    this->lag = lag;
    this->threshold = threshold;
    this->influence = influence;
}
 
template <size_t sampleSize>
void PeakDetection<sampleSize>::GetStdDev(uint8_t start, uint8_t length, float* data, float& avgRet, float& stdRet) {
    float average = 0.0f;
    float stdDev = 0.0f;
 
    for (uint8_t i = 0; i < length; i++) {
        average += data[start + i];
    }
 
    average /= (float)length;
 
    for (uint8_t i = 0; i < length; i++) {
        stdDev += powf(data[start + i] - average, 2.0f);
    }
 
    avgRet = average;
    stdRet = sqrtf(stdDev / (float)length);
}
 
template <size_t sampleSize>
void PeakDetection<sampleSize>::Calculate(float* data, bool* peaks) {
    float average = 0.0f;
    float stdDev = 0.0f;
    float maxData = 0.0f;
 
    for (uint8_t i = 0; i < sampleSize; i++) {
        filData[i] = 0.0f;
        avg[i] = 0.0f;
        std[i] = 0.0f;
        maxData = Mathematics::Max(maxData, data[i]);
    }
 
    if (maxData > threshold) {
        GetStdDev(0, lag, data, average, stdDev);
 
        avg[lag - 1] = average;
        std[lag - 1] = stdDev;
 
        for (uint8_t i = lag; i < sampleSize - lag; i++) {
            if (fabs(data[i] - avg[i - 1]) > threshold * std[i - 1]) {
                if (data[i] > avg[i - 1]) peaks[i] = true;
                filData[i] = influence * data[i] + (1.0f - influence) * filData[i - 1];
            } else {
                peaks[i] = false;
                filData[i] = data[i];
            }
 
            GetStdDev(i - lag + 1, i, data, avg[i], std[i]);
 
            avg[i] = average;
            std[i] = stdDev;
        }
    } else {
        for (uint8_t i = 0; i < sampleSize; i++) {
            peaks[i] = false;
        }
    }
}