1. Closing
One of the important morphological operations applied to either grayscale or binary images is Closing. 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 (Closing)

3. 1 2 3 4 5 Definitions of the components/Keywords:
The morphological Closing operation performs dilation followed by erosion, using the same structuring element for both the operations .
Closing function smoothes contours, links neighboring features, and fills small gaps or holes.
The operation effectively brightens small objects in binary and grayscale images. Like the opening operation, primary objects retain their original shape.
Closing removes thin filaments of background pixels.
The effect of the closing operator is to preserve background regions that have a similar shape to this structuring element, or that can completely contain the structuring element, while eliminating all other regions of background pixels. 2 3 4 5

4. Master Layout 1 1
Original Image
Dilated Image
Image after closing 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 dilated 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 dilated 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 dilated 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 dilated 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
The resulting image is the dilated image 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
After dilation is done, erosion process is started 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 dilated image is now getting eroded 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 dilated image is now getting eroded by the same structuring element 5

14. 3 Step 10: 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 dilated image is now getting eroded by the same structuring element 5

15. 3 Step 10: 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 closing. 5

16. 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 16
Credits

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

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

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

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