high pass filter implement on a image

hello. i want to apply a high pass filter on a image. i m not understanding how apply a ideal high pass filter on image.please any one guide me.

[Pekko Tuominen]

Do you mean ideal in the same sense as a rectangular frequency filter is ideal for 1D signals? Or ideal with respect to the end result in some visual sense?

Answer 1

[Image Analyst]

There may be no ideal filter. Here's one possibility:

kernel = [-1 -1 -1;-1 8 -1;-1 -1 -1];
filteredImage = imfilter(grayImage, kernel, 'same');

You could also do filtering in the Fourier domain if you want.