I'm posting this for one of the GaTech users working with MPEGs and 
the Display.

Mark

>Date: Sun, 17 Mar 2002 02:19:25 -0500 (EST)
>From: Yisrael Lowenstein <gte356h at prism.gatech.edu>
>To: <squeakers at cc.gatech.edu>
>Cc: <squeak at cs.uiuc.edu>
>Subject: [squeakers] 32-bit BMP problems.
>Sender: owner-squeakers at cc.gatech.edu
>Reply-To: squeakers at cc.gatech.edu
>
>I have been working with loading bitmaps in squeak to do Digital Video
>Special Effects for SqueakEnd and have come across a problem:
>
>here's my test code:
>
>aform := Form fromBMPFileNamed: 32bitbitmap.BMP.
>Transcript show: (aform colorAt: 1 at 1).
>
>this will return "Color transparent" even though it is clearly not!
>
>I have narrowed the problem down to the fact that these are represented
>differently internally than other 32 bit forms.  if you explore the bitmap
>of aform, you will se a bunch of SmallIntegers.  If you grap a 32 bit
>bitmap from the screen (using "anotherForm := Form fromUser." while you
>are in a 32-bit display depth) and explore that form's bitmap, you will
>see that it is made up of LargePositiveIntegers.  Consequently, colorAt:
>works just great on anotherForm...
>
>So, event though both of these (the fromUser form and the bmp-file form)
>claim to be 32-bit forms, they are represented differently internally.  Is
>this a bug?  or some sort of limitation?  how can I get around it?
>
>Any help would be GREATLY appreciated.
>
>	Lushi
>
>  o      |Yisrael Lowenstein: Computer Science Master's Student & Squeaker
>    ()  o|lushi at bigfoot.com; gte356h at prism.gatech.edu; lushi at cc.gatech.edu
>o_/||\/ |"Before you criticize a man, walk a mile in his shoes. That way
>    ||   | when you do criticize him, you'll be a mile away and have his
>   _/\_  | shoes." - Unknown                    AIM: YisraelL  ICQ: 1037061
>   Class Schedule: http://www.prism.gatech.edu/~gte356h/schedule/


-- 
--------------------------
Mark Guzdial : Georgia Tech : College of Computing : Atlanta, GA 30332-0280
Associate Professor - Learning Sciences & Technologies.
Collaborative Software Lab - http://coweb.cc.gatech.edu/csl/
(404) 894-5618 : Fax (404) 894-0673 : guzdial at cc.gatech.edu
http://www.cc.gatech.edu/gvu/people/Faculty/Mark.Guzdial.html