Summary: AMERICAN UNIVERSITY OF BEIRUT
FACULTY OF ENGINEERING AND ARCHITECTURE
DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING
EECE691C Digital Signal Processing Laboratory Week 6
2-D Digital Systems Pre-lab
1 Overview and Goals
The concept of systems can be generalized to multidimensional signals, such as images. In this
lab, you are going to look at some simple image processing systems. First, basic single-pixel gray
level transformations will be introduced. Next you are going to learn about histogram-
equalization that can be thought of as an image-specific gray level transformation. Last, you will
try out some spatial filters, which are somehow equivalent to 2-dimensional convolution.
2 Gray Level Transformations
An image processing system that looks at every input pixel gray level and generates a
corresponding output gray level according to a fixed gray level map is referred to as a basic gray
level transformation. You might think of this transformation as an analytic function, or a mapping
performed through a discrete table. The figures below represent some gray level transformations.
Use MATAB's vectorization and vector indexing to implement each gray level mapping. Do NOT
use loops. Select 2 grayscale images of your choice, and apply the 3 systems on both. Identify the
operation performed by each.
[General hint: When you load a grayscale image using imread, your answers will be of type uint8 and