[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: SDK vs ZIP?



Bryan Parkoff <none@nospam.net> wrote:
>     What is the difference between SDK and ZIP compression utility?  Apple 
> II does have ZIP utility, but it is very slow at 1MHz.  I tried to compress 
> using ZIP on Apple IIgs at 7MHz so it seems running okay little faster for 
> couple minutes.  It seems that SDK is little faster.  Why?

SDK (ShrinkIt) is using a combination of RLE and LZW.  Zip is using
Deflate, which is a very different algorithm.  Deflate is fairly slow
when compressing data, much faster when uncompressing.

ShrinkIt is hand-coded assembly, the Zip utility is probably C code.

-- 
Send mail to fadden@fadden.com (Andy McFadden) - http://www.fadden.com/
CD-Recordable FAQ - http://www.cdrfaq.org/
CiderPress Apple II archive utility for Windows - http://www.faddensoft.com/
Fight Internet Spam - http://spam.abuse.net/spam/ & http://spamcop.net/