Histogram Equalization

This slides about Histogram Equalization: Basic Idea and Definition

1. Unit 3 Image Enhancement Image Histogram Equalization Lecture By Kalyan Acharjya k alyan5.blogspot.in Lecture No 11

2. Histogram It is a plot of frequency of occurrence of an event.

3. Histogram An image histogram is a graphical representation between number of pixels and intensity values. It plots the number of pixels vs. each intensity value .

4. Draw the Image Histogram

5. Why Histogram? Indentifying the contrast of a image Numbers of Objects Thresholding Segmentation

6. Histogram Processing Types of processing: Histogram equalization Histogram matching (specification) Local enhancement

7. Histogram Processing The histogram of a digital image with gray levels from 0 to L-1 is a discrete function h( r k )= n k , where: r k is the kth gray level n k is the no pixels in the image with that gray level n is the total number of pixels in the image k = 0, 1, 2, …, L-1 Normalized histogram: p( r k )= n k /n S um of all components = 1

8. Histogram Equalization Histogram equalization (HE) results are similar to contrast stretching but offer the advantage of full automation. S ince HE automatically determines a transformation function to produce a new image with a uniform histogram.

9. Results after Histogram Equalization

10. Result after Histogram Equalizations

11. How and why does it work ?

12. Perform the Histogram Equalization on the following Image *This numerical copied from The Educational Channel (You Tube)

13. Histogram Equalization

14. Assignment Online Submission Due Date 30 Sept 2018 1. Comments on Role of Digital Image Processing in Modern Imaging Based Medical Treatments. 2. Explain your view on Importance of Image Understanding in Recent Computer Vision Applications Mid Term 1 Marks and Assignment Submission links are available at kalyan5.blogspot.in OR You can directly visit at http://bit.do/dipr_jnu

15. Any Questions? Thank You