DocumentCode
1010519
Title
On the hardness of finding optimal multiple preset dictionaries
Author
Mitzenmacher, Michael
Author_Institution
Div. of Eng. & Appl. Sci., Harvard Univ., Cambridge, MA, USA
Volume
50
Issue
7
fYear
2004
fDate
7/1/2004 12:00:00 AM
Firstpage
1536
Lastpage
1539
Abstract
We show that the following simple compression problem is NP-hard: given a collection of documents, find the pair of Huffman dictionaries that minimizes the total compressed size of the collection, where the best dictionary from the pair is used to compress each document. We also show the NP-hardness of finding optimal multiple preset dictionaries for LZ´77-based compression schemes. Our reductions make use of the catalog segmentation problem, a natural partitioning problem. Our results justify heuristic attacks used in practice.
Keywords
Huffman codes; data compression; dictionaries; optimisation; Huffman coding; LZ´77-based compression schemes; NP-hard; catalog segmentation problem; natural partitioning problem; optimal multiple preset dictionaries; two-stage compression; Code standards; Computational efficiency; Concurrent computing; Costs; Decoding; Dictionaries; Encoding; Huffman coding; Testing; Transform coding;
fLanguage
English
Journal_Title
Information Theory, IEEE Transactions on
Publisher
ieee
ISSN
0018-9448
Type
jour
DOI
10.1109/TIT.2004.830778
Filename
1306550
Link To Document