# Digital Image Processing 7th MJ13 EC2029

Anna University , Chennai
Question Paper
B.E./B.TECH DEGREE EXAMINATION , MAY/JUNE 2013
Seventh Semester
Electronics and Communication Engineering
EC 2029 / EC 708 – DIGITAL IMAGE PROCESSING
(Regulation 2008)

GATE  |  TANCET  |  Govt & PSU Papers  |  Bank Papers  |  Travel Tips

PART A – (10 X 2 = 20 marks)

1. Define Optical illusion and Mach band.
2. Define checker board effect and false contouring.
3. Give the PDF of Gaussian noise and plot it.
4. Define and give the transfer function of contraharmonic filter.
5. Define image degradation model and sketch it.
6. Define rubber sheet transformation.
7. Write sobel horizontal and vertical edge detection masks.
8. Define region splitting and merging.
9. State the optimality conditions for Huffman code.
10. State the need for data compression.

PART B – (5 X 16 = 80 marks)

11. (a) (i) Explain the basic concepts of sampling and quantization with neat sketch. (8)
(ii) Find the DCT Transform and its inverse for the given 2X2 image [ 3 6 ; 6 4 ]
(Or)
(b) (i) Obtain forward KL transform for the given vectors.
X1 = [ 1 0 0 ] ; X2 = [ 1 0 1 ] ; X3 = [ 1 1 0 ] (Transpose these vectors) and analyse how the principal components are used for remote sensing applications?

12. (a) Describe histogram equalization. Obtain histogram equalization for the following image segment of size 5 X 5. Write the interference on the image segment before and after equalization.

20 20 20 18 16
15 15 16 18 15
15 15 19 15 17
16 17 19 18 16
20 18 17 20 15 (5 X 5) matrix (16)
(Or)
(b) (i) Describe how homomorphic filtering is used to separate illumination and reflectance components? (8)
(ii) How mean filters are used for image enhancement. (8)

13. (a) Describe constrained least square filtering for image restoration and derive its transfer function. (16)
(Or)
(b) (i) Explain the concepts of geometric transformation for image restoration? (8)
(ii) How weiner filtering is helpful to reduce the mean square error? (8)

14. (a) (i) How do you link edge pixels through global processing? (8)
(ii) Describe Watershed segmentation algorithm. (8)
(Or)
(b) (i) Explain region based segmentation and region growing with an example. (8)
(ii) Discuss how to construct dams using morphological operation? (8)

15. (a) (i) Briefly explain transform coding with neat sketch. (8)
(ii) A source emits letters from an alphabet A = {a1 , a2 , a3 , a4 , a5} with probabilities P(a1) = 0.2 , P(a2) = 0.4 , P(a3) = 0.2 , P(a4) = 0.1 and P(a5) = 0.1. (8)
(1) Find the Huffman code for this source?
(2) Find the average length of the code and its redundancy?
(Or)
(b) (i) Generate the tag for the sequence 1 3 2 1 for the probabilities P(1) = 0.8 ,P(2) = 0.02 , P(3) = 0.18. (8)
(ii) How an image is compressed using JPEG image compression standard? (8)