how to apply a filter on image?

I want to apply a filter such that it's hot spot or origin lies in the center of the image. Please suggest me a matlab code to do it.

Answer 1

[David Young]

The hot spot is positioned relative to the filter bounds, not relative to the image bounds. To apply a filter, use conv2 or filter2. There are examples in the Image Processing Toolbox documentation.

The 'same' shape option to conv2 has the effect of putting the hot spot at the centre of the filter, provided its size on each axis is odd.