Digital Image Processing

Homework 3, Due 5/22

Problem 1

Lowpass Filtering

(a) Implement the Gaussian lowpass filter in Eq. (4.3-7). You must be able to

specify the size, M x N, of the resulting 2D function. In addition, you must be able

to specify where the 2D location of the center of the Gaussian function.

(b) Download Fig. 4.11(a) [this image is the same as Fig. 4.18(a)] and lowpass

filter it to obtain Fig. 4.18(c).

Fig4.11(a).bmp

 

Problem 2

Highpass Filtering Using a Lowpass Image

(a) Subtract your image in Problem 1 from the original to obtain a sharpened

image, as in Eq. (4.4-14). You will note that the resulting image does not resemble

the Gaussian highpass results in Fig. 4.26. Explain why this is so.

(b) Adjust the variance of your Gaussian lowpass filter until the result obtained by

image subtraction looks similar to Fig. 4.26(c). Explain your result.

Fig4.11(a).bmp

 

ftp your homework to

ftp://csc551@ftp.csie.nuk.edu.tw

in the directory 影像處理\HW3

by the following format:

檔案名稱:hw#_學號.zip

例如:資工同學,作業3

    檔案名稱:hw3_a09355xx.zip

The password is given in class.