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2. content. We will give an introduction to Rate Distortion theorySome examples will be included. Han Vinck 2012. 3. Fundamental quantity in Information theory . entropy The minimum average number of binary digits needed tospecify a source output (message) uniquely is called SOUR
                
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1. Introduction to rate-distortion theory A.J. Han Vinck
University of Essen
May 2012 
2. 2 content  We will give an introduction to Rate Distortion theory
Some examples will be included
 Han Vinck 2012 
3. 3 Fundamental quantity in Information theory			 Han Vinck 2012 
4. 4  Recall: Express everything in bits  0 and 1 Han Vinck 2012 
5. 5 Han Vinck 2012 
6. 6 model Han Vinck 2012 
7. 7 Rate Distortion Theory Han Vinck 2012 The distortion is a part of the problem
The set of representatives is fixed
The distortion is a part of the problem
The set of representatives is fixed
 
8. 8 Han Vinck 2012 
9. 9 Source representation   Han Vinck 2012 
10. 10 Source representation I( X; X ) 	= H(X)  H(X|X) = H(X)  H(X|X)
	 H(X) 	= I( X; X )  +  H(X|X)      (now H(X|X) ? 0)
Hence, 	minimizing I(X;X) for all possible transitions X ? X  giving an average
  distortion D  gives a lower bound R(D) for the representation of  X  Han Vinck 2012 
11. 11 Formal definition The rate distortion function for X and X is formally defined as
	 Han Vinck 2012 
12. 12 Example 1 Han Vinck 2012 
13. 13 Example 1: explanation Han Vinck 2012 
14. 14 Example 2: binary source  Han Vinck 2012 
15. 15 Han Vinck 2012 
16. 16 Example 2 Han Vinck 2012 
17. 17 quantization Han Vinck 2012 
18. 18 Quantization for Gaussian X with mean 0 Han Vinck 2012 
19. 19 Quantization for uniformly distributed X with mean 0 Han Vinck 2012 
20. 20 Han Vinck 2012