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.