video capture from window display

Pbm: I have a device that shows a microscope capture through usb port device interface. I would like to capture the video flow to process the images for research purposes.

I've tried several available codes with directshow that works for webcams and similar devices but they don't work because the interface device is not known.

Is there a way to capture the the video flow at a certain point of the system? Any helpful suggestion is welcome Thx 开发者_如何转开发:)

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If the microscope is not using directshow, then you will have to try to get access to the developers' API to access the data directly. You try using a screen grabber, but in all likelihood the use of overlay will prevent you getting access to the decoded frames.

If they are using directshow, there is more hope. You won't be able to break into their filter graph, since the directshow interfaces do not work well cross-process, but you should be able to locate their source device and build your own filter graph.

G