Example_of_Signal_Processing_on_Linux/SignalProcessor.hpp at master · CarlPoirier/Example_of_Signal_Processing_on_Linux · GitHub

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class SignalProcessor {


public:

    SignalProcessor() {

    }


    // Find out delay between two signals using cross-correlation
    // We assume delay is positive
    static int GetDelay(int16_t* buffer1, int16_t* buffer2, size_t samplesQty) {

        long long* correlation = new long long[samplesQty]();

        for (unsigned int i = 0; i < samplesQty; i++) {

            for (unsigned int j = 0; j < samplesQty; j++) {

                //std::cout << buffer1[j] << " ";
                correlation[i] += buffer1[j] * buffer2[(i+j < samplesQty)*(i+j)];

            }

        }

        // Find correlation peak
        unsigned int peak = 0;
        long long maxValue = 0;
        for (unsigned int i = 0; i < samplesQty; i++) {

            if (correlation[i] > maxValue) {
                maxValue = correlation[i];
                peak = i;
            }

        }

        delete[] correlation;

        return peak;

    }


    // We assume delay is positive
    static void Delay(int16_t* buffer, unsigned int samplesQty, int delay) {

        for (int i = samplesQty-1; i >= 0; i--) {

            buffer[i] = (i-delay >= 0)*buffer[(i-delay)];

        }

    }


    // Scale a signal using integer math, with numerator and denumerator of scale
    static void Scale(int16_t* buffer, size_t samplesQty, int num, int denum) {

        for (int i = 0; i < samplesQty; i++) {

            buffer[i] = buffer[i]*num/denum;

        }

    }


    // Subtract buffer 2 from buffer 1
    static void Subtract(int16_t* buffer1, int16_t* buffer2, size_t samplesQty) {

        for (int i = 0; i < samplesQty; i++) {

            buffer1[i] -= buffer2[i];

        }

    }


    ~SignalProcessor() {

    }

};