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Compression Field Expands

Just after we finish a special issue comparing the major compression programs (thanks, Ken!), the industry burps and spits out another few entrants. The compression market started with Pack-It, then StuffIt, and then StuffIt Deluxe and Compact Pro and DiskDoubler and Diamond, and now up pop the shareware AutoSqueeze, the DoubleUp board from Sigma Designs, the Gold Card from Pinnacle Micro, and SuperDisk! from Alysis Software.

You’ve heard about the main programs and the DoubleUp board already, so I’ll restrict myself to the new stuff. In many ways, AutoSqueeze from Dawson Dean is the most interesting, because it’s a shareware entry and because it’s simple to use. Once you install the AutoSqueeze INIT, to keep a file or a folder (and all the files in it) compressed you add the word "compressed" to the end of the name. Once you’ve done that, AutoSqueeze automatically compresses the file or folder and automatically expands when needed, although since there is no progress dialog, it seems that the Mac has slowed down a lot. There are a few problems with this technique. First, adding a long word like "compressed" to a file name may be obvious, but it’s not particularly easy to do and restricts file names significantly. A user-definable extension in the Control Panel interface would be best. Second, AutoSqueeze doesn’t change the file type, creator, or icon, so there’s no way to tell if a file is compressed without reading the name (as I’m sure many Mac users fail to do when they’re looking for a certain file in icon view). Because of this, it would be easy to copy a compressed file to floppy without expanding it, rendering it useless on the other end if the recipient didn’t use AutoSqueeze. AutoSqueeze’s main problem, though, is that it’s not as fast as DiskDoubler, nor can it compress files as much. Since the shareware price of $20 isn’t that much less than DiskDoubler’s $45 price, I’d recommend DiskDoubler over AutoSqueeze, if only for the excellent support provided by Salient. Otherwise, I am quite impressed with AutoSqueeze – if it had shown up two years ago it would have been an instant hit.

The DoubleUp board from Sigma Designs was the first hardware compression unit, but Pinnacle Micro followed quickly with its Gold Card. The DoubleUp board uses a compression chip from Stac Technology (a major compression force in the PC world and makers of the Stacker, a PC compression card), and the Gold Card uses a chip from Stac’s main competitor, InfoChip Systems, makers of Expanz!, the first PC compression card. Unlike the DoubleUp card, which uses DiskDoubler as an interface to choose which files to compress and expand, the Gold Card completely takes over, using software that compresses and expands all files all the time. Pinnacle Micro claims the card can compress at 600K per second and expand at about 1 MB per second, which is why it opted for complete compression of all files. Nonetheless, I use some programs and files so often that I wouldn’t want any slowdown in loading and quitting. The Gold Card will list for $395, which is more than the $229 DoubleUp, but Pinnacle says that its card is better and thus worth more. That’s a succinct way of explaining the price difference. If you don’t want complete transparency, Aladdin Software plans to bundle the Gold Card with StuffIt Deluxe, and that bundle will not include Pinnacle’s software.

The final entry into the compression battles claims to destroy other programs in benchmark tests. Alysis claims that its SuperDisk! creates slightly smaller files than do StuffIt Deluxe and DiskDoubler and is significantly faster. Compact Pro can supposedly create smaller files, but Alysis claims SuperDisk! is much faster. I haven’t seen SuperDisk! yet (it should be out in a few weeks for a list price of $89), but if it’s as fast as claimed, I’ll be impressed. In its first release, SuperDisk! includes a free decompression utility and will be able to make self-extracting archives with only 5K of overhead, a full 8K less than Compact Pro’s self-extracting archives. When I talked to Alysis, they said that they would probably support other file formats, such as the aging but still popular StuffIt 1.5.1 format, in the next release. Alysis will use a scheme similar to AutoSqueeze’s, but you only have to add ".s" to the end of the file or folder name, and apparently (I haven’t checked this personally), SuperDisk! can compress applications, something AutoSqueeze can’t do. SuperDisk! has an option to provide progress feedback, something which AutoSqueeze needs badly.

And for those of you who like a little rumor to spice up your lives, wait for DiskDoubler 4.0. An extremely reliable but thoroughly anonymous source says that DiskDoubler 4.0 will compress files more than Compact Pro (and thus more than anything currently out there, although SuperDisk! may change that). DiskDoubler 4.0 will work with System 7.0 and will solve some current problems (such as not being able to open a compressed file into a currently active application under MultiFinder) simply by using System 7.0. So many choices and so little time!

Pinnacle Micro — 800/553-7070 — 714/727-3300
Alysis Software — 415/566-2263
Salient — 415/321-5375 — 800/326-0092

Information from:
Alysis rep — Alysis on America Online

Related articles:
MacWEEK — 26-Feb-91, Vol. 5, #8, pg. 1
MacWEEK — 22-Jan-91, Vol. 5, #3, pg. 10
InfoWorld — 25-Feb-91, Vol. 13, #8, pg. 38
PC WEEK — 21-Jan-91, Vol. 8, #3, pg. 28

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