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Image in front panel gets overwritten by the next VI

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I need to display an image before and after the threshold, but my issue is when using the same image path, the threshold VI will overwrite the first image indicator. This is a simplified version on my code. Why is this happening and how do I resolve this?

 

Kwan90_0-1576737068585.png

 

I attached a random grey scale image as well. Why does the image look like the quality has been reduced after the first image read?

 

Thank you in advance,

Kwan

 

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Solution
Accepted by topic author Ddarma

Those IMAQ wires are references to the data. The indicators update when the data that is referred to is modified. So, subsequent VIs that modify the data update the indicator.

 

IIRC, set the indicator to "snapshot mode" will fix that.

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Thanks! That solved the problem. 

 

The only situation I can think of for snapshot to be turned off is when I want a constantly updating image like viewing a camera. Is there any other reasons to have snapshot turned off?

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@Ddarma wrote:

The only situation I can think of for snapshot to be turned off is when I want a constantly updating image like viewing a camera. Is there any other reasons to have snapshot turned off?


I guess it's a matter of taste. It's been a while, but I think I turned snapshot on for all indicators as well.

 

The entire IMAQ model is not intuitive for LabVIEW, IMHO. Being forced to name images is just nasty, as naming things creates a global resource. And globals are usually not a good thing.

 

IMAQ is the reason I'm making an OpenCV library that works by value. Time prohibited, it will probably be done in two years 😒.

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