View Full Version : Overlay Bitmap

February 29, 2004, 03:56:57

Can I use the opacity for the bitmap overlay? In the sample code has am SRCCOPY what's this? Have a percentage for opacity?

Other question is can I made with this activex a simple Video Character Generator? Can I put bitmaps scroll, craw in the video? and text too?

Can anybody help me?


Stefan Geissler
March 1, 2004, 08:15:45
Hello ChingLing,

Opacity (alpha blending) is not supported by the OverlayBitmap.

Yes, you could make a simple Video Character Generator . You must create the bitmap, that is painted on the live video on your own and copy it with BitBlt (See Windows API GDI functions) on the OverlayBitmap.
SRCCOPY is a Windows API defined constant for the BitBlt() and Stretchblt() functions. It means, that the source bitmap is copied without changes on the target bitmap.