Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!helios!perkins
From: perkins@cs.tamu.edu (Stephen Perkins)
Newsgroups: comp.sys.mac.programmer
Subject: Format if PICT(1) 'bitData' type
Message-ID: <11750@helios.TAMU.EDU>
Date: 4 Feb 91 04:42:24 GMT
Sender: usenet@helios.TAMU.EDU
Distribution: comp.sys.mac.programmer
Organization: Computer Science Department, Texas A&M University
Lines: 23

I have been trying to decode a version 1 PICT file and I have
been unable to find a definition for the 'bitData' data type.
This type is used inside a PackBitsRect (among other things)
and may contain data that has been packed by the PackBits routine.

Inside Mac vol 5 (pg 105) gives the definition of a pixData data type,
but I don't think that bitData and pixData are quite the same
thing. Note #4 on page 104 describes how PICT files version 2 
differ from version 1.  It is here that they mention the 
bitData data type.  I couldn't find the definition in 
vol. 1 and I am hoping that someone out there may have it
in a technical note (or possibly know it off hand...)!

Also, does anybody know the format of data encoded with
the PackBits routine.  I am writing a non-mac application
and I need to decode PICT files (and, therefore, data encoded
with PackBits) without using any toolbox routines.

Any help would be greatly appreciated!

Thanks,

Steve Perkins  ( perkins@cssun.tamu.edu )