IMAQ Overlay - Probe more consistent than image

[ChristophF]

Hi, I am having a certain problem that might be more aesthetic than problematic.

 Imaqdx Grab runs in a loop, aquiring frames in real time which then are processed within this loop, and finally some calculated points are overlayed onto the image. The last thing I do in this loop is send the image with overlay to a front panel image control, so that the user can see the results overlayed on the image in real time.

However, the image is very "flickery", so mainly the image appears without results overlayed and they show up only from time to time,. The results are correctly calculated for each frame though. If I use a probe to look at the purple image wire just before it goes to the indicator in the block diagram, the probe constantly shows the overlayed lines without any flickering.

I hope I made myself semi-clear, if not see picture attached. Does anybody have a clue why this could be?

Thanks in advance

[Gregory]

Do you call any property nodes for the image indicator in your code? That could cause some things to change on the front panel without affecting the data that you are sending to the image control. Also, if you right click on a wire and click "clean up wire" it will take many kinks out, and if you make the wires only run from left to right, it will make the code a little bit easier to read. Let me know!

[Alexander_Sobolev · Accepted solution]

Where do you have clear overlay to remove previous measurements? It is better to place it before new overlay to give labview more time to show it.

May be I am wrong, but indicator can be only a command to show image and drawing happens in separate thread later.

And probe creates copy of image data when it is called and does not progress untill it finishes copying. With image I prefer to do it manually: have a separate image display buffer (Create image.vi) and copy there after all processing and overlay is done (copy image.vi).

[ChristophF]

Thanks for both your suggestions: I added Clear Overlay as well as doing the copying trick and it is working without a hitch now. Great!