VIDEO_OPEN

VIDEO_OPEN_PARMS

Contains information defining the channel type to open on a video capture device.

typedef struct {
    DWORD dwSize;         //size of this structure
    FOURCC fccType;       //see below
    FOURCC fccComp;       //reserved; not used
    DWORD dwVersion;      //see below
    DWORD dwFlags;        //see below
    DWORD dwError;        //see below
    LPVOID pV1Reserved;   //reserved; not used
    LPVOID pV2Reserved;   //reserved; not used
    DWORD dwDevNode;      //see below
} VIDEO_OPEN_PARMS;       //see below

fccType

Four-character code identifying the type of channel being opened. For capture devices, this is set to "vcap".

dwVersion

Current version number of the video capture command being used. Set this to VIDEOAPIVERSION.

dwFlags

Flags identifying the type of channel. The following flags are defined:

VIDEO_EXTERNALIN	Specifies a channel that loads data from an external source into a frame buffer. This can also be called the capture channel.
VIDEO_IN	Specifies a channel that transfers data from the frame buffer to system memory.
VIDEO_OUT	Specifies a channel that transfers data from system memory to the frame buffer.
VIDEO_EXTERNALOUT	Specifies a channel that controls display of frame buffer images. Display might be either on a second monitor, or via overlay.

dwError

Error value the driver should return to the client application if it fails the open.

dwDevNode

Device node in the registry for the plug and play capture driver; the value refers to the section of the registry that contains configuration information for the driver.

This structure is identical to the ICOPEN structure used by installable compressors. This lets a driver handle both video capture and decompressor messages with a single DriverProc entry point.