As you know, Ptr<Filter> cv::cuda::createMedianFilter (int srcType, int windowSize, int partition=128) function added to OpenCV3.1.0.
I'm trying to do a median filter on 8 bit large images (6000*6000) with custom window size(up to 21). I compare cv::medianBlur and cv::cuda::createMedianFilter and results was
windowSize cv::medianBlur cv::cuda::createMedianFilter
3 0.071 sec 3.637 sec
5 0.285 sec 3.679 sec
11 2.641 sec 3.652 sec
19 2.566 sec 3.719 sec
1) why cuda::createMedianFilter is slower than cv::medianBlur?
2) How can i write a kernel code to implement median filter that use opencv Mat with custom kernel size?