john@viper.Lynx.MN.Org (John Stanley) (05/06/88)
I'd appreceate information on what exactly the PackBits format is.
Don't bother telling me it's used to compress data, I already know
that. What I need to know is -how-it-works-.
I want to write some tools to read/write mac compatable compressed
files on other computers....
Thanks....
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John Stanley (john@viper.UUCP)
Software Consultant - DynaSoft Systems
UUCP: ...{amdahl,ihnp4,rutgers}!meccts!viper!johndarin@Apple.COM (Darin Adler) (05/07/88)
In article <885@viper.Lynx.MN.Org> john@viper.Lynx.MN.Org (John Stanley) writes: > I'd appreceate information on what exactly the PackBits format is. This is described in Macintosh Technical Note #171: PackBits Data Format. The data consists of a byte count followed by a run of bytes. If the byte count is positive, it is followed by that many bytes + 1. If the byte count is negative, the following byte is repeated that many times + 1. For example: packed data: FE AA ; -2, repeat 3 times 02 80 00 2A ; 2, use next 3 bytes FD AA ; -3, repeat 4 times 03 80 00 2A 22 ; 3, use next 4 bytes F9 AA ; -7, repeat 8 times unpacked data: AA AA AA 80 00 2A AA AA AA AA 80 00 2A 22 AA AA AA AA AA AA AA AA -- Darin Adler AppleLink:Adler4 UUCP: {sun,voder,nsc,mtxinu,dual}!apple!darin CSNET: darin@Apple.com
cyosta@taux01.UUCP (Yossie Silverman) (05/10/88)
Can some kind soul tell me what the format of region data in a PICT resource is? I am trying to write a program (on a mainframe) that will convert PICT resources to GKS Metafile format and I need this information. I realize that it will not be guerantied to work forever, but if it works at all that is enough for me me. Further, I would appreciate the format of the 512 byte header in PICT files for the same reason. Thanks in advance. Yossie Silverman -- Yossie Silverman What did the Caspian sea? National Semiconductor Ltd. (Israel) - Saki UUCP: taux01!yossie@nsc.UUCP NSA LSD FBI KGB PCP CIA MOSAD NUCLEAR MI5 SPY ASSASSINATE SDI -- OOCLAY ITAY