Audio Senoidal generador

#define NOMINMAX
#include <windows.h>
#include <iostream>
#include <cmath>
#include <limits>
#include <fstream>
#include <string>

typedef signed short                    BitDepth;// 16bit audio
typedef unsigned long long QWORD;

const double pi = 3.141592653589;
const DWORD samplerate              =   44100;
const WORD channels                 =   2;
const unsigned short SOUND_DURATION =   1;//    1 second for example.
const QWORD NUM_SAMPLES             =   SOUND_DURATION * samplerate * channels;

void sineWave(BitDepth buffer[], double freq) {
    BitDepth amplitude = std::numeric_limits<BitDepth>::max()*0.5;
    QWORD c=0;
    double d=(samplerate/freq);
    for(QWORD i=0; i<NUM_SAMPLES; i+=channels) {
        double deg=360.0/d;
        buffer[i] = buffer[i+(1*(channels-1))] = sin((c++*deg)*pi/180)*amplitude;
    }
}

template<typename _Ty> void write(std::ofstream& stream, const _Ty& ty) {
    stream.write((const char*)&ty, sizeof(_Ty));
}

void writeWaveFile(const char* filename, BitDepth* buffer) {
    std::ofstream stream(filename, std::ios::binary);

    stream.write("RIFF", 4);
    ::write<int>(stream, 36+(NUM_SAMPLES*sizeof(BitDepth)));
    stream.write("WAVEfmt ", 8);
    ::write<int>(stream, 16);
    ::write<short>(stream, 1);
    ::write<unsigned short>(stream, channels);
    ::write<int>(stream, samplerate);
    ::write<int>(stream, samplerate*channels*sizeof(BitDepth));
    ::write<short>(stream, channels*sizeof(BitDepth));
    ::write<short>(stream, sizeof(BitDepth)*8);
    stream.write("data", 4);
    ::write<int>(stream, NUM_SAMPLES*sizeof(BitDepth));
    stream.write((const char*)&buffer[0], NUM_SAMPLES*sizeof(BitDepth));
    stream.close();
}

int main(int argc, char** argv) {
    SetConsoleTitleA("PCM Audio Example");

    std::string filename = "sine";

    BitDepth* buffer = new BitDepth[NUM_SAMPLES];
    memset(buffer, 0, NUM_SAMPLES*sizeof(BitDepth));

    sineWave(buffer, 1000.0);


    writeWaveFile(std::string(filename+std::string(".wav")).c_str(), buffer);
    delete[] buffer;

    std::cout << filename << ".wav written!" << std::endl;
    std::cin.get();
    return 0;
}