Playing Back Captured Video Data, Using VCKernel.lib
If a device supports video playback, its kernel-mode video capture driver must provide a DrawFrameFunc function, which VCKernel.lib can call in response to a request from a user-mode driver. This function copies bitmap data in the device’s frame buffer, while performing data conversion operations, if necessary. If the device supports playback, the driver’s GetOverlayModeFunc function must provide a return value that indicates the video formats the device can accept.