c++ open cv 中YUV422怎么转raw

将YUV422图像转换为原始（RAW）图像需要进行以下步骤：

1. 对于每个像素，从YUV422中提取Y值。
2. 对于每两个像素，从YUV422中提取U和V值。
3. 将U和V值插入到相邻的像素中，得到RGB值。
4. 将RGB值写入原始图像。

下面是一个示例代码：

// 读取YUV422图像
cv::Mat yuv422_image = cv::imread("input.yuv", cv::IMREAD_UNCHANGED);

// 创建原始图像
cv::Mat raw_image(yuv422_image.rows, yuv422_image.cols, CV_8UC3);

// 将YUV422转换为原始图像
for (int i = 0; i < yuv422_image.rows; i++) {
    for (int j = 0; j < yuv422_image.cols; j += 2) {
        // 提取Y值
        uint8_t y1 = yuv422_image.at<uint8_t>(i, j);
        uint8_t y2 = yuv422_image.at<uint8_t>(i, j + 1);

        // 提取U和V值
        uint8_t u = yuv422_image.at<uint8_t>(i, j + 1);
        uint8_t v = yuv422_image.at<uint8_t>(i, j + 3);

        // 计算RGB值
        int r1 = y1 + 1.13983 * (v - 128);
        int g1 = y1 - 0.39465 * (u - 128) - 0.58060 * (v - 128);
        int b1 = y1 + 2.03211 * (u - 128);

        int r2 = y2 + 1.13983 * (v - 128);
        int g2 = y2 - 0.39465 * (u - 128) - 0.58060 * (v - 128);
        int b2 = y2 + 2.03211 * (u - 128);

        // 写入原始图像
        raw_image.at<cv::Vec3b>(i, j)[0] = r1;
        raw_image.at<cv::Vec3b>(i, j)[1] = g1;
        raw_image.at<cv::Vec3b>(i, j)[2] = b1;

        raw_image.at<cv::Vec3b>(i, j + 1)[0] = r2;
        raw_image.at<cv::Vec3b>(i, j + 1)[1] = g2;
        raw_image.at<cv::Vec3b>(i, j + 1)[2] = b2;
    }
}

// 保存原始图像
cv::imwrite("output.raw", raw_image);