#include <bits/stdc++.h>
#include <libopenmpt/libopenmpt.hpp>
 
int main(int argc, char* argv[]) {
    constexpr size_t buffersize = 480;
    constexpr int32_t samplerate = 48000;
    if (argc < 2) {
        std::cout << "nuh uh\n";
        return 1;
    }
    std::ifstream file(argv[1], std::ios::binary);
    openmpt::module mod(file);

    mod.set_render_param(openmpt::module::render_param::RENDER_INTERPOLATIONFILTER_LENGTH, 1); // no interpolation

    std::ofstream stream("data.pcm", std::ios::binary);
    try {
        std::vector<int16_t> pcm_buffer_left(buffersize);
        std::vector<int16_t> pcm_buffer_right(buffersize);
        while (true) {
            std::size_t count = mod.read(samplerate, buffersize, pcm_buffer_left.data(), pcm_buffer_right.data());
            if (count == 0) break;
            stream.write(reinterpret_cast<const char*>(pcm_buffer_left.data()), count * sizeof(int16_t));
            stream.write(reinterpret_cast<const char*>(pcm_buffer_right.data()), count * sizeof(int16_t));
        }
        stream.close();
    }
    catch (const std::bad_alloc&) {
        std::cerr << "Error: out of memory\n";
        stream.close();
        return 1;
    }
    catch (const std::exception& e) {
        std::cerr << "Error: " << std::string(e.what() ? e.what() : "unknown error") << '\n';
        stream.close();
        return 1;
    }

    return 0;
}

ffmpeg -f s16le -ar 48k -ac 2 -i data.pcm output.wav