VTU Computer Science (Semester 6)
Data Compression
May 2016
Total marks: --
Total time: --
INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary


1(a) Define data compression. With an example, explain the process of modeling and coding.
6 M
1(b) Develop a Huffman code for the character sequence 'zigzagzip' generated by a source. Draw the Huffman tree for the code. Comput the entrophy of the source, average length of the Huffman code and its redundancy.
10 M
1(c) Verfiy if the code {0, 10, 101, 001, 110, 1110} is uniquely decodable.
4 M

2(a) A receiver received some encoded symbols from channel that were encoded using LZW algorithm. The received symbols and initial dictionary are as given below.
Encoded symbols: 3 4 1 2 1 3 2 5 11 13 9 11.
Initial Disctionary
Index 1 2 3 4 5
Entry 1 N O P -

i) Decode the symbol sequence
ii) Reverse the decoded sequence and encode it using the same initial dictionary.
10 M
2(b) Explain in detail, the coding scheems used in group - 3 facsimile apparatus.
10 M

3(a) Define autocorrection. Write short note on ARMA (N,M) model.
6 M
3(b) Briefly explain the function of a quantizer. Show that, for every bit being included in uniform quantizer of uniformly distributed source, the signal-to-noise ratio increases by 6dB.
10 M
3(c) Highlight the various distortion criterions used in lossy compression schemes.
4 M

4(a) Explain vector quantization in detail.
8 M
4(b) With necessary diagrams, explain Delta modulation. Also explain how the error developed can be avoided.
12 M

5(a) Find the inverse z-Transform of \(F(z)\dfrac{6z^{2}-9z}{z^{2}-2.5z+1} \)
6 M
5(b) How are the elements of DCT and DST matrix represeted? Derive the DWHT transform matrix.
6 M
5(c) Briefly explain the fundamental concept of the following in relation with Linear systems. Sealing, Time Invariance, Transfer Function, Impuse Response.
8 M

6(a) With a neat block diagram, explain iin detail the basic sub band coding algorithm.
10 M
6(b) With a block diagram, explain MPEG - AAC encoder.
10 M

7(a) Explain multi-resolution analysis and scaling function with an example.
10 M
7(b) With a neat diagram, explain SPIHT.
10 M

8(a) With a neat diagram, explain H.261 video coding algorithm.
10 M
8(b) Explain H.264 advanced video coding.
10 M



More question papers from Data Compression
SPONSORED ADVERTISEMENTS