Re: areaDetector Overlay problem

[Mark Rivers via Tech-talk <tech-talk at aps.anl.gov>]

Hi Jörn,

• Shouldn't the overlay plugin add another image to the output att a defined address (5 in this case)?

No, the plugin does not use different addresses for the output for each overlay (1-8).  It always uses address 0.

Each overlay (1-8) is independent and the output image contains all of those overlays that are enabled, so you could have both a cursor and text, for example.

Since you are not seeing the overlay when you use address 0, that could be because of the following:

• The NDPluginOverlay itself is not enabled.  You must enable both the overlay plugin and the specific overlays (1-8) that you want.
• The color of the overlay is not set to a very visible color.
• The width is set too small.  If the width is 1 and you are using a viewer that downsizes the original image for your screen that can result in some pixels not being displayed at all.  Try increasing the width to 3, for example.

Please send a screenshot of NDOverlayN or NDOverlay8 so we can see how you have defined the overlay features.

Mark

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From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Jörn Dreyer via Tech-talk <tech-talk at aps.anl.gov>
Sent: Thursday, September 5, 2024 2:22 AM
To: EPICS Talk <tech-talk at aps.anl.gov>
Subject: areaDetector Overlay problem

 

Hi,

currently I have a problem to get the overlay plugin working. I would like to draw a cursor onto my image.
I have an ADBase set up with an asynPort "cam1". I connect an Overlay plugin "OVER1" to the output of this asynPort with asyn address set to 0.
I defined the cursor "CURSOR1" at NDOverlay8 line 5 and enabled it.
An NDStdArray is connected to asynPort "OVER1".
And here the problem starts. If I set the asyn address to 0, I see the original image from the camera.
If I set it to 1...X nothing happens. No more images are seen.
Shouldn't the overlay plugin add another image to the output att a defined address (5 in this case)?
Or did I understand the functionality of plugins completely wrong?

Any help appreciated.

Joern