Presenter: Cheng – Yeh Tsao 100 Mbits adaptive data compressor design using selectively shiftable content-addressable memory S. Jones, PhD, CEng Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom, IEE PROCEEDINGS-G, Vol. 139, No. 4, AUGUST I992 Presenter: Cheng – Yeh Tsao

Outline Data compression BSTW algorithm Architecture Conclusions

Data compression Huffman coding Lempel – Ziv coding Arithmetic coding High probability of occurrence Lempel – Ziv coding Sliding window Arithmetic coding Creating a code string which represent a fractional value on the number line between 0 and 1

BSTW (Bentley, Sleator, Tarjan and Wei ) algorithm Data in Table length: -It is effect the match probability Tuple size: -It is effect the frequency of match Coding strategy: -It is effect the complexity DEFG n m LMON HIJK ABCD DEFG 1 2 3 ABCD DEFG 1 DEFG 1 ABCD 2 HIJK 2 HIJK 3 LMON 3 LMON Address Data

Architecture (1/2) Organization of selectively shiftable content-addressable memory

Architecture (2/2) Chip architecture

Conclusion The algorithm can reduce text and image data to around two-thirds of its original volume It is shown that a selectively shiftable CAM can support rapid data compression

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