cv::Mat::step

1. step[0]是矩阵中一行元素的字节数
2. step[1]是矩阵中一个元素的字节数(elemSize)

step1 = step / elemSize1，elemSize1是元素的每个通道所占的字节数

1. step1(0)是矩阵一行元素的通道数（不是很贴切）2
2. step1(1)是矩阵一个元素的通道数（channel()）

    Mat img(3, 4, CV_16UC4, Scalar_<uchar>(1, 2, 3, 4));

    cout << img << endl;
    cout << "step:" << img.step << endl;
    cout << "step[0]:" << img.step[0] << endl;
    cout << "step[1]:" << img.step[1] << endl;
    cout << "step1(0):" << img.step1(0) << endl;
    cout << "step1(1):" << img.step1(1) << endl;

Result:

image.png