## Digital Image Processing - Dec 2016

### Electronics Engineering (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.

### Solve any four Q1 (a,b,c,d,e)

**1(a)** Justify the statement "Quality of picture depends on the no: of pixels and the no: of gray level representing the pictures".(5 marks)
**1(b)** Explain RGB color model to represent a digital image.(5 marks)
**1(c)** Can two different images have the same histogram? Justify your answer.(5 marks)
**1(d)** Define chain codes in 4-connectivity and 8-connectivity.(5 marks)
**1(e)** Compare arithmetic coding and Huffinan coding.(5 marks)
**2(a)** Apply the following Image Enhancement techniques for the given 3 bits per pixel image segment.$ 1=\begin{bmatrix}
2 & 1 & 2& 1& 0\\\\
7 & 1 & 4& 3& 2\\\\
2& 4& 1& 3& 7\\\\
1& 3& 4& 6& 3\\\\
1& 4& 1& 3& 4
\end{bmatrix} $/

i) Digital Negative

ii) Bit plane Slicing

iii) Thresholding with T=5(10 marks)
**2(b)** Perform histogram equalization and plot the histograms before and afte equalization.

Gray level | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |

No.of pixel | 128 | 75 | 280 | 416 | 635 | 1058 | 820 | 684 |

**2(b)**Explain various image enhancement techniques in frequency domain.(10 marks)

**3(a)**Givethe 7×7 Image segment,perform diation using the structuring element shown: Structuring element:

1 | 0 |

0 | 1 |

0 | 0 | 0 | 0 | 0 | 0 | 0 |

0 | 1 | 0 | 1 | 0 | 1 | 0 |

0 | 1 | 0 | 1 | 0 | 1 | 0 |

0 | 1 | 0 | 1 | 0 | 1 | 0 |

0 | 1 | 1 | 1 | 1 | 1 | 0 |

0 | 0 | 0 | 1 | 0 | 0 | 0 |

0 | 0 | 0 | 1 | 0 | 0 | 0 |

**3(b)**Explain image segmentation based on similarity with help of examples.(10 marks)

**4(a)**A source emits 6 symbols with the following probabilities. Construct the Huffman code and calculate the average code word length and coding efficiency.

Symbol | A | B | C | D | E | F |

Probability | 0.2 | 0.3 | 0.06 | 0.15 | 0.04 | 0.25 |

**4(b)**Explain with block diagram the transform based coding.(10 marks)

**5(a)**Check whether the DFT matrix is unitary or not and calcuate the 2D-DFT of the given image segment using matrix multiplication method $$f(x,y)=\begin{matrix} 0 & 0& 0 & 1\\ 1 & 2& 0& 0\\ 1 & 0& 1& 1\\ 2& 0& 2& 0 \end{matrix}$$(10 marks)

### write a short note any two Q6.(a,b,c,d)

**6(a)** Hit or Miss Transformation(10 marks)
**6(b)** Discrete Wavelet Transform(10 marks)
**6(c)** Thresholding techniques(10 marks)
**6(d)** Image file format(10 marks)