Re: LZ: Compression program (and questions for asm programmers)
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At 01:01 PM 9/11/96 -0400, you wrote:
>On Tue, 10 Sep 1996, Scott J. Rein wrote:
>
>
>
>Lempel-Ziv is very inefficient with pseudo-random data. Here's an
>exercise: using whatever graphics program you like, create an image where
>every contiguous pixel is a different colour, using a noise filter or
>whatever. Save the file in 2 formats - .BMP and .GIF.
>
>Most of the time, the BMP will actually be smaller than the GIF, even
>though it is a "raw" bitmap with no compression. This is because the GIF
>(which uses an LZW algorithm) is unable to compress most of the
>pseudorandom data, and so the tokens actually increase the filesize.
>
>It works well for pictures and text, but not for programs or other
>pseudorandom files.
>
>-Isaac
>
What compression method would you suggest? I downloaded all of the files
from the ftp site, but I don't really know what to make of them.
-- Scott Rein
srein@rain.org
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