ECE 470: Introduction to Robotics Homework 6
Question 1.
1) A gray scale image I of our campus has a dimension of 945x1680 shown in Fig. 1. A
region of interest (ROI) from row 391 to 420 and column 1071 to 1100 is specified to
encompass a window in the scene with an array of intensity values as shown in Fig. 2.
This ROI is denoted as I_ROI= I (391:420, 1071:1100).
Fig. 1
a) For a 5x5 sub-region I_subROI= I_ROI (10:14,26:30),
i. Write down the intensity matrix. You may choose to demarcate this region on
Fig. 2 itself. (1 point)
ii. Tabulate the available intensity values and their respective occurrence. Plot the
histogram (4 points)
iii. Perform histogram equalization and plot the new histogram (6 points)
iv. Comment on the histograms produced in (ii) and (iii) (1 points)
b) Determine the transformed intensity value of I_subROI (5,5) using a 3x3 mean filter
𝐹𝑚𝑒𝑎𝑛 =
1
3×3
[
1 1 1
1 1 1
1 1 1
] (2 points).
Question 2
2) The image, I is being operated by 3 different kernel operators independently to
produce output images G1, G2 and G3 as shown in Fig. 3. The following operators
are being used
𝐹1 = [
−1 0 1
−2 0 2
−1 0 1
], 𝐹2 = [
−1 −2 −1
0 0 0
1 2 1
], 𝐹3 = [
. 11 . 11 . 11
. 11 . 11 . 11
. 11 . 11 . 11
]
With some explanation, match the operators with their respective output images.
Fig. 3
(6 points)
