I have an image and I want to perform OpenCV boxFilter
on a ROI
of this image.
image = cv::imread(argv[1], CV_LOAD_IMAGE_COLOR);
cv::Rect roi( 10, 10, 64, 64);
cv::Mat output;
cv::boxFilter(image(roi),output,-1,cv::Size(scale_size,scale_size));
I want to know what happen if the kernel is out of the ROI
? Use the pixels out of the ROI
but still within the image to do the filtering or just use the value specified by the BorderType
?
Actually I want to use the former to do the filtering.
... the answer is actually incorrect (will be deleted when it is un-accepted) ...