User`s guide

FrameGrabInter val
Purpose Specify how often to acquire frame from video stream
Description The FrameGrab Interval property specifies how often the vide o input
object acquires a frame from the video stream. By default, objects
acquire every frame in the video stream, but y ou can u se this property
to specify other acquisition intervals.
Note Do not confuse the frame grab interval with the frame rate. The
frame rate d escribe s the rate a t which an image acquisition device
provides frames, typically measur ed in seconds, such as 30 fram es pe r
second. The frame grab interval is m easured in frames, not seconds. If
a particular device’s frame rate is configurable, the video source object
might include the frame rate as a device-specific property.
For example, when you specify a FrameGrabInterva l value of 3,the
object acquires every third frame from the video stream, as illustrated
in this figure. The object acquires the first frame in the video stream
before applying the
FrameGrabInterval.
Yo u specify the source of the video stream in the SelectedSourceName
property.
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