## Image Processing - Dec 2011

### Information Technology (Semester 7)

TOTAL MARKS: 80

TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.

(2) Attempt any **three** from the remaining questions.

(3) Assume data if required.

(4) Figures to the right indicate full marks.
**1(a)** Classify the following DT system on linearity, time invariance causality

(i) y(n)- 2ny(n-1)=x{n}

(ii) y(n)=x^{2}{n}

(iii) y(n)=2^{x(n)}x{n}(5 marks)
**1(b)** The first five DFT co-efficient of a real eight point sequence x{n} are

X{0} = 0.5, X{1} = 2+j, X{2} = 3+2j, X{3} = j, X{4} = 3,

find the remaining co-efficients. (5 marks)
**1(c)** Show that the first difference of its chain code normalizes to its rotation.(5 marks)
**1(d)** Median filter is the best solution to remove salt and pepper noise. Justify.(5 marks)
**2(a)** Obtain the Hadamard matrix of N=8.(6 marks)
**2(b)** List any two properties of 2-D-DFT. Prove any one of them. (4 marks)
**2(c)** Using a 4 point FFT algorithm, evaluate 2-D DFT of the following image

(10 marks)
**3(a)** Explain the following operation:

(i) Erosion

(ii) Dilation

(iii) Skeletonization

(iv) Prunning(10 marks)
**3(b)** Consider the image given below. Calculate the direction of the edge at the centre of point of the image

(10 marks)
**4(a)** Explain JPEG baseline compression scheme in detail.(5 marks)
**4(b)** Explain sub band coding in image compression using Wavelet transform.(5 marks)
**4(c)** Compute the coding redundancy of the following image using Huffman code

(10 marks)
**5(a)** Find a difference equation of a DT causal LTI system which has ?{n} as input and cos [(?/4) n] is output. Derive the necessary equation.(10 marks)
**5(b)** Impulse response of FIR filter is given by h(n) = {1,1}. Find the response of the system to input x{n} where x{n} = {2,2,4} using FFT/IFFT.(10 marks)
**6(a)** For the 3-bit 4X4 image perform the following operation:-

(i) Negative

(ii) Thresholding with T=4

(iii) Intensity level slicing with background r_{1}=2 & r_{2}=5

(iv) bit-plane slicing for MSB & LSB

(8 marks)
**6(b)** If the 1-DCT kernel is g(x,u) =

Find The DCT of given image:

(8 marks)
**6(c)** Discuss the limitations of the Laplacian operator for edge detection compared with the gradient operators.(4 marks)

### Write short notes on any two :-

**7(a)** Object Detection using coorelation principle.(10 marks)
**7(b)** Region based segmentation.(10 marks)
**7(c)** Content Based Image Retrieval (C.B.I.R)(10 marks)
**7(d)** Copyright marking.(10 marks)