spolsky-joel@CS.YALE.EDU (Joel Spolsky) (04/12/89)
I did a few benchmarks with LZHUF on a Sun today. Compression was about 10% better than 16-bit compress (Ziv Lempel Welch compression with 9 bit codes expanding to up to 16 bits). I'm going to do some large scale testing to make sure this is reliable. If anybody wants a copy of the source code suitable for SunOS 4.0 (and probably many other unices) send me eMail. The only major change is replacing ints with shorts. +----------------+----------------------------------------------------------+ | Joel Spolsky | bitnet: spolsky@yalecs.bitnet uucp: ...!yale!spolsky | | | internet: spolsky@cs.yale.edu voicenet: 203-436-1483 | +----------------+----------------------------------------------------------+ #include <disclaimer.h>
davidsen@steinmetz.ge.com (Wm. E. Davidsen Jr) (04/13/89)
In article <56625@yale-celray.yale.UUCP> spolsky-joel@CS.YALE.EDU (Joel Spolsky) writes: | If anybody wants a copy of the source code suitable for SunOS 4.0 (and | probably many other unices) send me eMail. The only major change is | replacing ints with shorts. I'm sending a request by mail, but I'll make a few comments here. First, converting int to short will only put off the problem, since many machines don't have 16 bit short. There are some logic errors which assume "silent anding" to 16 bits, and I admit I haven't found them all. Also, I have a version which works on over 99% of the files I've tried. It hangs on at least two, which work with the 16 bit version. Again I suspect a trunctation assumption. I also have another (just one) file which works on 386 and VAX but not on Sun or Convex. I believe it's related to using LSB byte order. I hope we can have a single version which will run on everything from Z80 to Cray. The original author has done a good job, let's try to get a really fixed version before propigating it. I have sent a test file to Rahul to help validate the new zoo versions. -- bill davidsen (wedu@crd.GE.COM) {uunet | philabs}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me