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Chapter 8 - Video Digitizer Components / Video Digitizer Components Reference

Video Digitizer Component Functions / Controlling Digitization

VDSetPlayThruOnOff

The VDSetPlayThruOnOff function allows applications to control continuous digitization.

pascal VideoDigitizerError VDSetPlayThruOnOff
                                 (VideoDigitizerComponent ci,
                                  short state);

ci

Specifies the video digitizer component for the request. Applications obtain this reference from the Component Manager's OpenComponent function.

state

A short integer that specifies whether to use continuous digitization. The following values are valid:

digitizerOff

Turns off continuous digitization

digitizerOn

Turns on continuous digitization

When an application stops continuous digitization, the video digitizer component must restore its alpha channel, blending mask, or key color settings to graphics mode.

DESCRIPTION

When opened, video digitizer components are always set to off, so that no digitization is taking place. Your application can use the VDSetPlayThruOnOff function to turn continuous digitization on and off.

RESULT CODES

noErr	0	No error
digiUnimpErr	-2201	Function not supported
qtParamErr	-2202	Invalid parameter value

SEE ALSO

Applications can also use single-frame digitization by calling the VDGrabOneFrame or VDGrabOneFrameAsync function, described in the next section and on page 8-56, respectively.

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