Ask about drawing the client
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A camera and a frame grabber have been set up. And the frame grabber has been installed in PCI. When I use continuous grab mode, the image data are written into a specified memory continuously and cover the old data. Then how can I update the image from the memory to the client screen since I have tried calling StretchDIBits in OnDraw(), but I find it is not efficient with the client area twinkling frequently. Is there any efficient way like copying the data directly to the display memory? How? Thanks
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A camera and a frame grabber have been set up. And the frame grabber has been installed in PCI. When I use continuous grab mode, the image data are written into a specified memory continuously and cover the old data. Then how can I update the image from the memory to the client screen since I have tried calling StretchDIBits in OnDraw(), but I find it is not efficient with the client area twinkling frequently. Is there any efficient way like copying the data directly to the display memory? How? Thanks
Override OnEraseBackground to do nothing.
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A camera and a frame grabber have been set up. And the frame grabber has been installed in PCI. When I use continuous grab mode, the image data are written into a specified memory continuously and cover the old data. Then how can I update the image from the memory to the client screen since I have tried calling StretchDIBits in OnDraw(), but I find it is not efficient with the client area twinkling frequently. Is there any efficient way like copying the data directly to the display memory? How? Thanks
For this kind of application DirectDraw is the best solution, With DirectDraw; Less PCI bandwith consumption. You can manipulate video memory directly in various video format. You can solve flickering/twinkling by Double Buffering, Waiting Vertical SYNC.