读取巨大的二进制文件 （~1.5 GB） 并将结果写入文本文件 C++

问：

我正在尝试逐块读取一个巨大的二进制文件，解码每个块并将其输出到文本文件中，以便于故障排除。到目前为止，我已经编写了一个代码来做到这一点，但它非常慢（需要几个小时才能解码整个文件）。

这是我的代码：

template<class T> std::vector<T> readBytes(std::ifstream& input, int numOfBytes) {
    std::vector<T> output;
    output.reserve(numOfBytes);

    T* buf = new T[numOfBytes];
    input.read((char*)buf, sizeof(T) * numOfBytes);

    for (int i = 0; i < numOfBytes; ++i) {
        output.push_back(buf[i]);
    }
    
    delete[] buf;
    return output;
}

std::ifstream file("lidar_Mission.dat", std::ios::binary | std::ios::ate);
std::streampos total_bytes(file.tellg());
file.seekg(12, std::ios::beg); //skip the header

while (file) {
    if (file.good()) {
        //Read the required chunk and store it in a vector
        std::vector<std::int8_t> time(readBytes<std::int8_t>(file, 8));
        std::vector<std::int8_t> lidarx(readBytes<std::int8_t>(file, 4));
        std::vector<std::int8_t> lidary(readBytes<std::int8_t>(file, 4));
        std::vector<std::int8_t> lidarz(readBytes<std::int8_t>(file, 4));
        std::vector<std::int8_t> intensity(readBytes<std::int8_t>(file, 2));
        std::vector<char> classification(readBytes<char>(file, 1));
        std::vector<char> Return_scan(readBytes<char>(file, 1));

        uint8_t timeArr[8] = { time[0], time[1],time[2],time[3],time[4],time[5],time[6],time[7] };
        uint8_t lidarxArr[4] = { lidarx[0], lidarx[1],lidarx[2],lidarx[3] };
        uint8_t lidaryArr[4] = { lidary[0], lidary[1],lidary[2],lidary[3] };
        uint8_t lidarzArr[4] = { lidarz[0], lidarz[1],lidarz[2],lidarz[3] };
        uint8_t intenArr[2] = { intensity[0], intensity[1] };
        uint8_t clssArr[1] = { classification[0]};
        uint8_t Retn_scnArr[1] = { Return_scan[0]};
                
        //Type punning
        double timestamp = *((double*)&timeArr);
        float x = *((float*)lidarxArr);
        float y = *((float*)lidaryArr);
        float z = *((float*)lidarzArr);
        uint16_t inten = *((uint16_t*)intenArr);
        uint8_t clss = *((uint8_t*)clssArr);
        uint8_t Retn_scn = *((uint8_t*)Retn_scnArr);
        
        //Write to a text file
        std::ofstream fout;

        fout.open("test2", std::ios::out | std::ios::app);

        fout << std::fixed << std::setprecision(9) << std::left << std::setw(19) << timestamp
            << std::setprecision(10) << std::setw(15) << x
            << std::setprecision(10) << std::setw(15) << y
            << std::setw(16) << z
            << std::setw(10) << inten
            << std::endl;
        fout.close();
    }else{
        throw std::exception();
    }
}

关于如何让它运行得更快的任何想法？谢谢