[comp.sys.mac.hypercard] Hypercard binary format

doug@eris (Doug Merritt) (04/24/88)

1) From what I've heard, the binary file format of hypercard is
undocumented. Has anyone reverse engineered it? Even partially?

2) I heard a rumor that Bill Atkinson said that he would release
the binary specs if and when someone came up with a Hypercard lookalike
on the IBM PC. Anyone know if this is true, or what it may imply?

3) A friend of mine wrote an article for BMUG that discusses Apple's
patent on image compression, which *may* have something (everything?)
to do with the hard part of the reverse engineering in #1 above.
Anyone interested in a summary? It was in the Fall 1987 BMUG, I
believe; author was Mark Thorson.

4) I'd like to be able to recognize hypercard binaries as such when
they get thrown onto other systems (BBS's, Unix, etc). Is there a
magic number or something that makes them easily identifiable?

Thanks for any and all help.

	Doug Merritt		doug@mica.berkeley.edu (ucbvax!mica!doug)
			or	ucbvax!unisoft!certes!doug
			or	sun.com!cup.portal.com!doug-merritt

alibaba@ucscb.UCSC.EDU (Alexander M. Rosenberg) (04/24/88)

HyperCard uses either 24 or 31 different compression schemes. I've forgotten
which. This makes reverse engineering it very impossible, leading me to
believe that HyperDA was written with help from Apple.

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