User`s guide

6 Acquiring Image Data
6-26
Specifying a Noncontiguous Acquisition
Although FramesPerTrigger specifies the number of frames to acquire, these frames
do not have to be captured contiguously from the video stream. You can specify that the
toolbox skip a certain number of frames between frames it acquires. To do this, set the
value of the FrameGrabInterval property.
Note The FrameGrabInterval property controls the interval at which the toolbox
acquires frames from the video stream (measured in frames). This property does not
control the rate at which frames are provided by the device, otherwise known as the
frame rate.
The following figure illustrates how the FrameGrabInterval property affects an
acquisition.
Impact of FrameGrabInterval on Data Logging
Determining How Much Data Has Been Logged
To determine how many frames have been acquired by a video input object, check the
value of the FramesAcquired property. This property tells how many frames the object
has acquired since it was started. To determine how many frames are currently available
in the memory buffer, see “Determining How Many Frames Are Available” on page
6-28.