T215 a Perform unsharp sharpening on the raw image using a m

T2.15

a) Perform unsharp sharpening on the raw image using a mean filter and a Gaussian filter (with the same kernel size). How do the sharpened images produced by the two different smoothing functions compare?

b) Try re- sharpening this image using a filter with larger kernel sizes (e.g. 5×5, 7×7 and 9×9). How does increasing the kernel size affect the result?

c) What would you expect to see if the kernel size were allowed to approach the image size?

Solution

a)The unsharp filter is implemented as a window based operator ,it relies on a convolution kernel to perform spatial filtering

In the image shose edges have been slightly blurred by camera focus .In order to extract q sharpened view of the edges , we smooth the image using mean filter and then substract the smooth ed result from the original image.