User`s guide

preview
Object State Preview Window Behavior
Running=on
If Trigge rType is set to immedia te or manual,the
Video Preview window continues to update the image
displayed.
If
TriggerType is set to hardware,theVideoPreview
window stops updating the image displayed until a
trigger occurs.
Logging=on
Video P review window might drop some data frames,
but this will not affect the frames logged to memory
or disk.
Custom
Update
Function
preview creates application-defined data for the im age object, himage,
assigning it the name
'UpdatePreviewWindowFcn' and setting its
valuetoanemptyarray(
[]). You can configure the value of the
'UpdatePreviewWindowFcn' application data and retrieve its v alue
using the MATLAB
setappdata and getappdata functions, respectively.
If you set the value of
'UpdatePreviewWindowFcn' to a function
handle,
preview invokes the function every time a new image frame is
available. You can use this function to define custom processing of the
previewed image data. When
preview invokes the function handle you
specify, it passes three arguments to your function:
•
obj — The video input obje ct being pre view ed
•
event — An event structure containing image frame information.
For more i nfo rmation, see below.
•
himage — A handle to the image object that is being upda t ed
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