## Image Processing - Dec 2013

### 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.

### Attempt the following

**1 (a)** Explain the fundamental of Digital Image Processing.(5 marks)
**1 (b)** What are different point processing techniques used for image enhancement?(5 marks)
**1 (c) ** What is segmentation? Explain why it is required?(5 marks)
**1 (d)** What is Image compression?(5 marks)
**2 (a)** Classify the signal as energy or power signal :-

$$x(n)=\left\{\begin{array}{l}{\left(\frac{1}{2}\right)}^n\ \ \&n\geq{}0 \\{\left(2\right)}^n\ \ \&n<0\end{array}\right.$$(5 marks)
**2 (b)** State whether system is linear/ Non-linear, Time-Variant/ Time-Invariant, Casual/Anticausal, Stable/Unstable :-

y(n)=nx(n).(5 marks)
**2 (c) ** Let x(n)={1,2,3,4}

(i) Find x[k]

(ii) Find DFT of x_{e}(n) and x_{o}(n) using x[k].(10 marks)
**3 (a)** Let x(n)={1,2,3,4,5,6,7} and h(n)={1,0,2} :-

**3 (b)**Given :-

$$F=\left[\begin{array}{cccc}1 & 1 & 2 & 1 \\2 & 1 & 1 & 2 \\1 & 3 & 2 & 1 \\2 & 1 & 2 & 1\end{array}\right]$$

Find 2D Hadamard transform?(10 marks)

**4 (a)**Given :-

$$f\left[x,y\right]=\left[\begin{array}{cc}4 & 5 & 6 \\7 & 8 & 9\end{array}\right]$$

$$f\left[x,y\right]=\left[\begin{array}{cc}1 & 1 \\1 & 1\end{array}\right]$$

Find linear convolution?(10 marks)

**4 (b)**Grey Level Histogram of an image is given below, compute Histogram Equalization. Draw the Histogram of input and output image:-

Grey Levels | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |

No. of Pixels | 790 | 1023 | 850 | 656 | 329 | 245 | 122 | 81 |

**5 (a)**Explain basic principle of detecting following in the images :-

(i) Points

(ii) Lines

(iii) Edges.(10 marks)

**5 (b)**Given below is table of eight symbol and their frequency of occurrence :-

Symbol | S_{0} | S_{1} | S_{2} | S_{3} | S_{4} | S_{5} | S_{6} | S_{7} |

Frequency | 0.25 | 0.15 | 0.06 | 0.08 | 0.21 | 0.14 | 0.07 | 0.04 |

Give Huffman code for each eight symbol. What is coding efficiency?(10 marks)

**6 (a)**Explain in detail Lossy image compression.(10 marks)

**6 (b)**Explain following terms :-

(i) Dialation

(ii) Erosion.(10 marks)

### Write short notes on any four :-

**7 (a)** Image Acquisition(5 marks)
**7 (b)** Filters in frequency domain.(5 marks)
**7 (c) ** Image segmentation(5 marks)
**7 (d) ** Walsh transform(5 marks)
**7 (e) ** Digital watermaking.(5 marks)