Axis - Image Lag

[Sandahl]

We are having issues getting the camera image to be fluid. We are using Labview. We believe the issue has to do with overall frame rate and compression that is being used. We are not sure where these setting are to be modified so they are maintained when viewed in the driver station. We have tried setting the resolution to 160x120, but the image shown is always 320x240. Can someone point us in the right direction.

Thanks
Team 2883

[TogetherSword8]

We are also using LabView, and our camera happened to just work. We didn't even know we had it hooked up until we accidentally opened the wrong program and all the sudden we had the picture. Maybe try restoring it to default settings?

Team 888

[Efiske]

It's strange, but for me the camera lag goes down when you crank up the camera settings. So, set size to 640x480, and compression to about 10.

You do this by opening up Begin.vi and changing the inputs into the various Camera VIs.

Alternatively, if your programmer has already implemented the vision processing code, that tends to mess with the camera's settings. Make sure you're using the default code (e.g. make a new project).

[Greg McKaskle]

The dashboard and cRIO have largely independent sessions to the camera. I suspect that there are settings which are shared between them, but I think I've also seen that the robot can request one image size and the dashboard another, and the camera gives everyone what they ask for.

I do not believe that setting the camera setting on the cRIO to 640x480 is a good move. It takes about 100ms to decode that image, and I don't see how it will improve the framerate to the dashboard.

If you are working on a good framerate to the dashboard, you can open the source to it and change the settings in the sample code. It uses the default cluster of 30,30,320x240 -- 30fps, 30% compression, and 320x240 pixels in size. Create the cluster constant if you want to make changes.

Before doing that, I'd add a loop timing to see how often it runs and see if you can determine the cause. One thing to watch for is low lighting. The camera will lengthen the exposure if the light levels are too low. This is unlikely to happen at competitions, but could easily happen in a practice or shop environment.

Greg McKaskle