Question

In spatial domain, which of the following operation is done on the pixels in sharpening the image?

(a) Integration

(b) Average

(c) Median

(d) Differentiation

This question was posed to me in an online quiz.

Question is from Sharpening Spatial Filters topic in chapter Intensity Transformations and Spatial Filtering of Digital Image Processing

Answer 1

Right choice is (d) Differentiation

For explanation I would say: We know that, in blurring the image, we perform the average of pixels which can be considered as integration. As sharpening is the opposite process of blurring, logically we can tell that we perform differentiation on the pixels to sharpen the image.