Labview Vision, Extract fraction of image after zoom and pan.

[BNJensen]

Hi all,

I need to extract and save a fraction of an image, after the user has used zoom an pan in an Image Display.

I already use ROI for something else...

I can't find any properties of the Image Display, which are useful for finding the coordinates of the view.

How can i find "left, top, right, bottom" of the view?

This (unresolved) topic deals with the a similar question:

how to determine what image pixels are currently displayed in an Vision Image display after zoom and...

Cheers,

BNJ

[p4keal · Accepted solution]

I assume this example can solve your problem. I use the properties: ZoomSingle, Image Central Position and Image Area Size. From their I can calculate the  the shown section and to create a rectangle for the IMAQ Extract2.

[BNJensen]

Ahh, Thanks p4keal!!

Great and illustrative reply!

It was the "Image Center Position", that I had missed, was actually changing with pan.

You saved my day

Cheers,

Brian

[p4keal]

You are wellcome 🙂

[LVUser77]

Hi p4keal,

I'm using LabVIEW 2017, and I could locate IMAQ Extract2 with the rectangle array you showed. Can you please upload your LabVIEW code?

Thank you so much in advance.

Best regards!

[AnalogKid2DigitalMan]

IMAQ Extract 2 is part of the Vision Development Module, a toolkit purchased separately from LabVIEW.

-AK2DM

[LVUser77]

Yes, I have Vision Acquisition Software 17.5 and Vision Development Module 2017. The IMAQdx Extract Image doesn't have any information on the displayed image.