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chingling
February 29, 2004, 04:56:57
Hi!

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?


Thanks
ChingLing

Stefan Geissler
March 1, 2004, 09:15:45
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.