1. Opening
One of the important morphological operations applied to either grayscale or binary images is Opening. It is derived from the fundamental operations Erosion and Dilation.
Course Name: Digital Image Processing Level(UG/PG): UG
Author(s) : Phani Swathi Chitta
Mentor: Prof. Saravanan Vijayakumaran
*The contents in this ppt are licensed under Creative Commons Attribution-NonCommercial-ShareAlike 2.5 India license

2. Learning Objectives
After interacting with this Learning Object, the learner will be able to:
Explain one of the morphological operations (Opening)

3. 1 2 3 4 5 Definitions of the components/Keywords:
The morphological Opening operation is erosion followed by dilation, using the same structuring element for both the operations .
The opening operation removes noise from an image while maintaining the overall sizes of objects in the foreground.
Opening is a useful process for smoothing contours, removing pixel noise, eliminating narrow extensions, and breaking thin links between features.
After using an opening operation to darken small objects and remove noise, thresholding or other morphological processes can be applied to the image to further refine the display of the primary shapes within the image.
Opening removes thin filaments of object pixels.
The effect of the opening operator is to preserve foreground regions that have a similar shape to this structuring element, or that can completely contain the structuring element, while eliminating all other regions of foreground pixels. 2 3 4 5

4. Master Layout 1 1
Original Image
Eroded Image
Image after opening 2 3
Give radio buttons to select any one structuring element of sizes 5x5, 7x7, 11x11
The structuring elements (SE) are 4 5

5. 3 Step 1: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
Show the original image first then show the structuring element selected by the user
The text in DT should appear in parallel to the figures
The original image
The structuring element 5

6. 3 Step 2: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The resulting image is the eroded image 5

7. 3 Step 3: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The resulting image is the eroded image 5

8. 3 Step 4: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The resulting image is the eroded image 5

9. 3 Step 5: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The resulting image is the eroded image 5

10. 3 Step 6: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
After erosion is done, dilation process is started 5

11. 3 Step 7: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The eroded image is now getting dilated by the same structuring element 5

12. 3 Step 8: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The eroded image is now getting dilated by the same structuring element 5

13. 3 Step 9: 1 2 4 5 Instruction for the animator
Text to be displayed in the working area (DT)
The SE must move on the original image such that the center of the SE must move pixel by pixel on the original image
The text in DT should appear in parallel to the figures
The right most image is the resulting image of opening. 5

14. Test your understanding
Electrical Engineering
Slide 1
Slide 3
Slide
23, 24,25
Slide 26
Introduction
Definitions
Analogy
Test your understanding
(questionnaire)‏
Lets Sum up (summary)‏
Want to know more…
(Further Reading)‏
Interactivity:
Try it yourself
Select any one of the figures
a b
c d
Select the structuring element 14
Credits

15. Questionnaire 1
1. What is the resulting image of fig. A after opening, using the Structuring Element
Fig. A
Answers: a) b)
c) d) None 2 3 4 5

16. Questionnaire 1
2. Fig. A is the resulting image after opening. What will be the original image(Opening is done using 7x7 Structuring Element)?
Fig. A
Answers: a) b)
c) d) 2 3 4 5

17. Questionnaire 1
3. After opening operation, will the resulting image look like original image?
Answers: a) Always
b) Sometimes
c) Never
d) None 2 3 4 5

18. Links for further reading
Reference websites:
Morphological processing Recap & Extend / Digital Image Processing Lecture Morphological processing Recap &Extend.pdf
_OPEN.html
Books:
Digital Image Processing – Rafael C. Gonzalez, Richard E. Woods, Third edition, Prentice Hall