smpte timecode from chrono

int main()
{
    uint64_t test_hours = 2;
    uint64_t test_minutes = 43;
    uint64_t test_seconds = 32;
    uint64_t test_frames = 3;

    std::cout << "EXPECTED: " << test_hours << ":" << test_minutes << ":" << test_seconds << ":" << test_frames << std::endl;

    double hr_ms = test_hours * 60 * 60 * 1000;
    double mi_ms = test_minutes * 60 * 1000;
    double s_ms = test_seconds * 1000;
    double fr_ms = 1000 * test_frames / 24.;

    double time = hr_ms + mi_ms + s_ms + fr_ms;
    uint64_t ut = static_cast<uint64_t>(time);

    auto ch_time = std::chrono::milliseconds(ut);

    int hours = std::chrono::floor<std::chrono::hours>(ch_time).count();
    int minutes = std::chrono::floor<std::chrono::minutes>(ch_time).count();
    int seconds = std::chrono::floor<std::chrono::seconds>(ch_time).count();
    int milliseconds = std::chrono::floor<std::chrono::milliseconds>(ch_time).count();

    minutes -= hours * 60;
    seconds -= ((hours * 60) + minutes) * 60;
    milliseconds -= ((((hours * 60) + minutes) * 60) + seconds) * 1000;

    double frames = std::floor(static_cast<double>(milliseconds) * 24. / 1000.);
    int frames_i = static_cast<int>(frames);

    std::cout << "ACTUAL:   " << hours << ":" << minutes << ":" << seconds << ":" << frames_i << std::endl;

    return 0;
}