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Lecture 2

Huffman Coding

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Multiple code

Letter Probability Code

a1a1 0.64

a1a2 0.016

a1a3 0.144

a2a1 0.016

a2a2 0.0004

a2a3 0.0036

a3a1 0.1440

a3a2 0.0036

a3a3 0.0324

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∑ P (aiaj) = 1

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Exercises

1. Using the Huffman tree constructed in this session, decode the

following sequence of bits, if possible. Otherwise, where does the

decoding fail?

10100010111010001000010011

2. Using the Huffman tree constructed in this session, write the bit

sequences that encode the messages:

test , state , telnet , notes

•

3. Mention one disadvantage of a lossless compression scheme and one

disadvantage of a lossy compression scheme.

4. Write a C/C++/Matlab program that implements the Huffman coding

algorithm.