This document contains questions and answers about image processing filters. It explains that the median filter is nonlinear as demonstrated by an example where the median of combined values is not equal to the median of individual values. It also identifies a convolution mask that enhances horizontal edges. Additionally, it analyzes two filters, determining that one is non-separable and emphasizes images while the other is separable and detects edges based on its coefficients summing to zero.

1. Questions and Answers

2. Q1.

3. Sol.
Rotate Horizontal and vertical operators in required direction

4. Q2. State which one of the following filters is nonlinear: High Boost
Filter, Weighted Averaging Filter, Sobel Filter, Median Filter. Justify your
answer with an example.

5. Soln. The answer is median. This can be demonstrated by simple
example, i.e., median(0,1,0)+median(2,0,0)=0+0=0. This is not the
same as the median of (2,1,0) which is 1.

6. Q3. Given this convolution mask, i) what type of filter is it? ii) How will
it affect the image?

7. Soln. Enhance horizontal edges (vertical lines)

8. Question
For each filter given below, answer the following questions.
a) Is it a separable filter? If yes, present the horizontal and vertical
filters.
b) What is the functionality of the filter? Explain your reasoning.

9. Solution
H_1: non-separable, high emphasis because coefficients sum to 1, but
has both positive and negative values.
H_2: separable, edge detection because coefficients sum to 0,