how can i use gocv mat's method replace the java submat method?

[busyfree]

Description

I'm using gocv to transfer java blindwatermark to go implement.

    //
    // java code
    //
    // C++: Mat Mat::operator()(Rect roi)
    //

    // javadoc: Mat::operator()(roi)
    public Mat submat(Rect roi) {
        return new Mat(n_submat(nativeObj, roi.x, roi.y, roi.width, roi.height));
    }

Your Environment

• Operating System and version: mac os 12.1
• OpenCV version used: 4.5.4
• How did you install OpenCV? brew install opencv
• GoCV version used: v0.29.0
• Go version: go1.17.5
• Did you run the env.sh or env.cmd script before trying to go run or go build? Yes

[zhifengzhuang]

maybe you can use Mat.Region?