change input image with camera

[grace.]

what block diagram i used if input image changes with input camera

 

[wiebe@CARYA]

You need a grab or snap VI. 

http://zone.ni.com/reference/en-XX/help/370281AG-01/nivisionlvbasics/acquire_or_read_an_image/

[grace.]

https://www.youtube.com/watch?v=-o2h3AQOuiE

what block diagram used ?

[wiebe@CARYA]

Look into grid calibration (Google).

There's no telling how their exact diagram looks like, without seeing it.