16位灰度图转8位

//16位灰度图转8位
static Mat Gray16To8(Mat &src, Mat &dst, int height, int width)
{
    double minv = 0.0, maxv = 0.0;
    double* minp = &minv;
    double* maxp = &maxv;
    minMaxIdx(src, minp, maxp);
    ushort *p_src;
    uchar *p_dst;
    for (int i = 0; i < height; i++)
    {
        p_src = src.ptr<ushort>(i);
        p_dst = dst.ptr<uchar>(i);
        for (int j = 0; j < width; j++)
        {
            p_dst[j] = (p_src[j] - minv) / (maxv - minv) * 255;
        }
    }

    return dst;
}