7CS6.3 Data Compression Techniques (Comp. Engg.) 


Units  Contents of the subjects 
Compression TechniquesCompression Techniques: Lossless, lossy, measure of performance, modeling & coding. Lossless compression: Derivation of average information, data models, uniquely decodable codes with tests, prefix codes, KraftMc Millan inequality. Huffman coding: Algorithms, minimum variance Huffman codes, optimality, length extended codes, adaptive coding, Rice codes, using Huffman codes for lossless image compression.  
Arithmetic coding with application to lossless compression. Dictionary Techniques: LZ77, LZ78, LZW Predictive coding: BurrowsWheeler Transform and movetofront coding, JPEGLS Facsimile Encoding: Run length, T.4 and T.6  
Lossy coding Mathematical preliminaries: Distortion criteria, conditional entropy, average mutual information, differential entropy, rate distortion theory, probability and linear system models. Scalar quantization: The quantization problem, uniform quantizer, Forward adaptive quantization, nonuniform quantizationFormal adopting quantization, companded Quantization Vector quantization: Introduction, advantages, The LindeRuzoGrey algorithm, lattice vector quantization.  
Differential encoding – Introduction, Basic algorithm, Adaptive DPCM, Delta modulation, speech and image coding using delta modulation. Sampling in frequency and time domain, ztransform, DCT, DST, DWHT, quantization and coding of transform coefficient.  
Sub band coding: Introduction, Filters, Basic algorithm, Design of Filter banks, G.722, MPEG. Wavelet based compression: Introduction, wavelets multiresolution analysis and the scaling function implementation using filters. 
Text/References:
1. Sayood K: Introduction to Data Compression: ELSEVIER 2005.