How to sharpen an image using OpenCV? There are many ways of smoothing or blurring but none that I could see of sharpening.
One general procedure is laid out in the wikipedia article on unsharp masking: You use a gaussian smoothing filter and subtract the smoothed version from the original image (in a weighted way so the values of a constant area remain constant).
To get a sharpened version of
The parameters there are something you need to adjust for yourself.
There's also laplacian sharpening, you should find something on that when you google.
you can find a sample code about sharpening image using "unsharp mask" algorithm at OpenCV Documentation
changing values of