Delay in data reading in image processing

[iErd]

Hello,

I get images from 3d cameras using labview .net libraries. I used clone subvi s because I wanted the image from these two cameras to work simultaneously in the labview environment. However, since one of these cameras has a connection problem, it is experiencing a delay in the image acquisition process. Cameras take images of moving parts. My main question here is what can I do to get the image simultaneously in LabView environment.

Camera communication is done via Ethernet. The first camera connection is made, then images are taken from the cameras to get more than one image from the camera, and when the program is stopped, the camera connection is disconnected. The state machine structure was used in the continuous data acquisition from the camera.
What are the parameters in the labview environment that can cause data delay when taking images from the camera?

[wiebe@CARYA]

You need 2 loops to do 2 things independently.

The 2 VIs will process the data in parallel, but the sequence will not continue to until everything in it is finished. So if 1 VI hangs, the structure will have to wait until it's done.

[iErd]

Hello,

I set the subvi I use as clone subvi. Sometimes two image data is delayed at the same time, sometimes only one of them is delayed in the range of milliseconds (200-300ms). 

Creating two separate parallel frame structures complicates my work because I can then save the data back to another subvi. I need to work on it. Is there any other solution?

Best regards

[wiebe@CARYA]

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@iErd wrote:

Creating two separate parallel frame structures complicates my work because I can then save the data back to another subvi. I need to work on it. Is there any other solution?

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Not really.

If you have two asynchronous processes, putting them in one loop will synchronize them.

If you split up the loop, as a consequence you'll have to a) 'centralize' the data or b) treat the data completely separately.

If you don't want a slow device to stall the loop, there are only hacks, like giving the VI a low time out (if possible). Then it won't stall, or at least not as long.

[iErd]

Hi,

In fact, I couldn't find the reason for the video delay in such a structure that has only one sequence and no time delay. Because it doesn't always do that. He rarely does. Subvi clear indicators when called option is also active.

Do you know anything more specific on the subject?

[wiebe@CARYA]

I know almost everything about the subject 😁.

Without seeing the subVI, it will be hard to get more specific.

Most means of communication can stall, and if it does, it will hang the loop it's in.