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Phil
April 13, 2005, 21:32:02
I'm using Imaging Control's Grabber class in a command-line (non-UI) application to capture a single image from a camera. Among other things, I call the grabber's methods startLive, snapImages, getActiveMemBuffer, and then stopLive. Briefly, the image appears and then disappears. Does anyone know why this is happening and how it can be prevented?

Thanks.

Stefan Geissler
April 14, 2005, 09:14:32
Hi Phil,

what do you mean with "image appears"?

The grabber creates an ActiveMovie Window, that will be destroyed, if stopLive has been called. Thus, no video image is displayed. If you want to see the grabbed image, you must write code to display it on your own.

Phil
April 14, 2005, 17:23:37
I run the application to capture an image from the command line, and it does so. However, I am expecting no user interface at all. It is supposed to happen in the background. Your library seems to display the captured image very briefly, and then it disappears. Naturally, there is no HWND assigned to the grabber for my application.

Tim Cassens
April 14, 2005, 18:11:30
Just pass false as parameter to your startLive call. The parameter of startLive determines whether live video is displayed on screen.

If the parameter is true (or not set, which defaults to true), live video is displayed in the window specified by setHWND or just in the top left corner of the screen if you did not specify a window at all.

If the parameter is false, no live video will be displayed, but all grabbing operations will still work.

Best regards
Tim Cassens

Phil
April 15, 2005, 01:41:38
Thanks Tim. Your solution worked.