Kernel-mode video capture drivers can provide three functions for setting device characteristics that are based on the channel configuration options defined by the user-mode driver. These functions are:
Code in VCKernel.lib calls these functions in response to requests from the user-mode driver, which are explained in Configuring Video Channels, Using VCUser.lib.
Whenever video data format characteristics are changed, the kernel-mode driver should call VC_SetImageSize to indicate the maximum number of bytes needed to store an image, using the current format.