User-Mode Video Capture Driver Messages

The following table lists the messages that the DriverProc function in a user-mode video capture driver can receive, along with the operation the driver performs when it receives each message. Message definitions are contained in msviddrv.h and msvideo.h.

Message	Operation Performed by Driver
DVM_CONFIGURESTORAGE	Saves or restores configuration information.
DVM_DIALOG	Displays a dialog box to obtain configuration information.
DVM_DST_RECT	Sets or retrieves destination rectangle parameters.
DVM_FORMAT	Sets or retrieves video-capture format parameters.
DVM_FRAME	Transfers data from the frame buffer.
DVM_GET_CHANNEL_CAPS	Returns channel capabilities.
DVM_GETERRORTEXT	Returns the text string associated with an error number.
DVM_GETVIDEOAPIVER	Returns the video API version used by the driver.
DVM_PALETTE	Sets or retrieves a logical palette.
DVM_PALETTERGB555	Sets a logical palette and an RGB555 translation table.
DVM_SRC_RECT	Sets or retrieves source rectangle parameters.
DVM_STREAM_ADDBUFFER	Adds a data buffer to a capture stream.
DVM_STREAM_FINI	Terminates a capture stream.
DVM_STREAM_GETERROR	Returns a stream’s error status.
DVM_STREAM_GETPOSITION	Returns the current position within a capture stream.
DVM_STREAM_INIT	Initializes a capture stream.
DVM_STREAM_PREPAREHEADER	Prepares a data buffer.
DVM_STREAM_RESET	Stops and resets a capture stream.
DVM_STREAM_START	Starts a capture stream.
DVM_STREAM_STOP	Stops a capture stream.
DVM_STREAM_UNPREPAREHEADER	Removes preparation from a data buffer.
DVM_UPDATE	Updates a screen overlay area.