couch@mill.me.toronto.edu () (06/24/88)
Does anyone have experience with gray scale images with MS Windows. I am trying to display a 16 level gray scale image within a Windows application. I am using a VGA compatible card (ATI VIP). If I retrieve the screen display context and create a compatible bitmap, the bitmap is in the following form: red scan 0..n-1 green scan 0..n-1 blue scan 0..n-1 where n is the height of the image in raster lines. Pixels in a scanline are represented by one bit per colour. The problem with this arrangement is that only eight colours can be specified. I want to use the full 16 available with the VGA standard. Thanks in advance.
roper@june.cs.washington.edu (Michael Roper) (06/26/88)
couch@mill.me.toronto.edu writes: > > Pixels in a scanline are represented by one bit per colour. > The problem with this arrangement is that only eight colours > can be specified. I want to use the full 16 available with > the VGA standard. Microsoft Windows has always used 3-plane bitmaps because they were concerned about performance. However, there is at least one driver for EGA systems which supports 4-plane bitmaps, providing 16 colors. The driver is called "EGA-16" and is available for about $40 from: hDC Computer Corp. 15379 N.E. 90th St. Redmond, WA 98052 phone (206) 885-5550 fax (206) 881-9770 Unfortunately, it does not support VGA, although it works fine with a VGA in EGA mode. hDC is currently working on VGA-64, which would provide 64 colors in some VGA modes. I don't know when they expect to ship. EGA-16 also comes with a Windows utility for setting your 16-color palette (from up to 256 available). If it matters, I work for hDC, although not on EGA-16. -- Mike Roper * "I think I'm going to sneeze." ARPA: roper@june.cs.washington.edu * "A Klingon?" "Sneeze?" UUCP: ihnp4!uw-beaver!uw-june!roper * "It's the only kind I know."