How can I do image processing operations only in ROI part of original image directly?

Question

Is that possible by using OpenCV to do some image processing operations only in ROI part of original image?

I search some articles on Internet. Most of codes look li

Answer 1

To blur the required region follow the following steps:

cv::Rect roi(x, y, w, h);
cv::GaussianBlur(image(roi), image(roi), Size(0, 0), 4); 

Follow this link for more information http://docs.opencv.org/modules/core/doc/basic_structures.html#id6

Mat::operator()(Range rowRange, Range colRange)

Mat::operator()(const Rect& roi)