>>>
>THIS SHOULD NOT BE THE CASE, IF YOU ARE GETTING DISTORTIONS THEN YOU HAVE A
>BUM COMPRESSION PROGRAM.
><<
>
>That's right Britt. LZW may have had some implementation issues from
>differing vendors. But the compression itself is considered "lossless",
>meaning that what goes in comes out.
>
>BTW I understand that LZW works by mapping out redundant pixels (ie. all
>the white ones, black ones, etc) rather than altering any individual
>pixels. Certainly any jpeg style artifacts are the result of poor
>programing or worse. The above should point out why LZW is not consistant
>with the resulting file size. Files with line work will benefit the most,
>while images with lots of complex details may not reduce much at all.
>
>Frank

I have actually seen file sizes increase when an image ia especially grainy!
Britt

Britt Griswold
Graphics And Publications
NASA Goddard Space Flight Center
Code 253  Bldg. 8  Rm. N15
Greenbelt, MD 20771

(301) 286-3381
(301) 286-1705 (FAX)
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