ECE547 Image Processing Sept 25, 2008
Exercise 3
Lecturer: Prof. Thomas Huang Due: Oct 9, 2008
Problem 1 (Compression Ratio)
Compute the compression ratio that you achieved in MP3. Assume that it takes the original image
was 128 ×128 with 8 bits per pixel. Suppose that it takes 7 bits to encode each row and column
value, 3 bits to encode a, and 8 bits to encode b. What is the compression ratio for blocksize=4
and blocksize=8?
Problem 2 Fractal Encoding
For these problems, it would be really helpful to have some program which draw can draw an
IFS. The easiest way is probably to use plotifs.m, which you should be able to obtain online at
http://courses.ece.uiuc.edu/ece547/exercises/plotifs.m1. In MATLAB, you can turn on
the grid using grid on.
Cross
Below is an image of a simple 2-D fractal. Find the corresponding IFS and its fractal (Hausdorff)
dimension.
−1/2 −1/3 −1/6 0 1/6 1/3
−1/2
−1/3
−1/6
0
1/6
1/3
1Other choices include using FRACTINT, if you can get a copy which runs on your system. You may also search
for Java IFS applets on the web.
E3-1
