VC_Capture

BOOL
VC_Capture(
    VCUSER_HANDLE vh,
    BOOL bAcquire
    );

The VC_Capture function requests the kernel-mode driver to enable or disable acquisition of video capture data into the frame buffer.

Parameters

vh

Handle to the kernel-mode driver, obtained from VC_OpenDevice.

bAcquire

Set to TRUE to enable capture, or FALSE to disable capture.

Return Value

Returns TRUE if successful. Otherwise returns FALSE.

Comments

User-mode video capture drivers should call VC_Capture with bAcquire set to TRUE when processing a DVM_STREAM_INIT command for the VIDEO_EXTERNALIN channel. They should call the function with bAcquire set to FALSE when processing a DVM_STREAM_FINI command for the VIDEO_EXTERNALIN channel.

Disabling capture when overlay is enabled has the effect of freezing the captured video.

The VC_Capture function calls DeviceIoControl (described in the Win32 SDK) to send either an IOCTL_VIDC_CAPTURE_ON or an IOCTL_VIDC_CAPTURE_OFF control code to the specified kernel-mode driver. When a kernel-mode driver using VCKernel.lib receives one of these control codes, its CaptureFunc function is called.