Article View: comp.sys.mac
Article #29250Re: some (should-be) ground-rules f
From: gillies
Date: Thu, 16 Jun 1988 18:46
Date: Thu, 16 Jun 1988 18:46
18 lines
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1223 bytes
When you learn a little bit compression algorithms, you find that
almost ANY algorithm can be misimplemented to get poor performance.
And the decompressor will still work!
I can implement anti-Huffman coding to EXPAND the data AS MUCH as
possible. The Huffman decompressor will still work.
I can implement LZW to do A RESET after every byte code. The data
will always expand to 300% of its original size (assuming 12-bit
codes). The LZW decompressor will still work.
Just because the data decompresses, doesn't mean it was compressed
well.. The LZW paper does not define a unique compression output.
Many possible outputs are possible, and some are VERY bad.
Don Gillies {ihnp4!uiucdcs!gillies} U of Illinois
{gillies@cs.uiuc.edu}
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Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!husc6!bbn!rochester!cornell!batcomputer!itsgw!mailrus!iuvax!pur-ee!uiucdcs!uiucdcsp!gillies From: gillies@uiucdcsp.cs.uiuc.edu Newsgroups: comp.sys.mac Subject: Re: some (should-be) ground-rules f Message-ID: <76000232@uiucdcsp> Date: 16 Jun 88 18:46:00 GMT References: <2758@utastro.UUCP> Lines: 18 Nf-ID: #R:utastro.UUCP:2758:uiucdcsp:76000232:000:750 Nf-From: uiucdcsp.cs.uiuc.edu!gillies Jun 16 13:46:00 1988