CameraServer telemetry exceptions

[Starlight220]

The log here has the following exceptions:

Mar 24, 2023 6:51:40 PM edu.wpi.first.shuffleboard.plugin.cameraserver.source.CameraServerSource lambda$new$5
WARNING: Could not get bandwidth
VideoException [edu.wpi.first.cscore.VideoException: empty value]
	at edu.wpi.first.cscore.CameraServerJNI.getTelemetryAverageValue(Native Method)
	at edu.wpi.first.cscore.CameraServerJNI.getTelemetryAverageValue(CameraServerJNI.java:364)
	at edu.wpi.first.cscore.VideoSource.getActualDataRate(VideoSource.java:334)
	at edu.wpi.first.shuffleboard.plugin.cameraserver.source.CameraServerSource.lambda$new$5(CameraServerSource.java:139)

Mar 24, 2023 6:51:40 PM edu.wpi.first.shuffleboard.plugin.cameraserver.source.CameraServerSource lambda$new$5
WARNING: Could not get framerate
VideoException [edu.wpi.first.cscore.VideoException: empty value]
	at edu.wpi.first.cscore.CameraServerJNI.getTelemetryAverageValue(Native Method)
	at edu.wpi.first.cscore.CameraServerJNI.getTelemetryAverageValue(CameraServerJNI.java:364)
	at edu.wpi.first.cscore.VideoSource.getActualFPS(VideoSource.java:321)
	at edu.wpi.first.shuffleboard.plugin.cameraserver.source.CameraServerSource.lambda$new$5(CameraServerSource.java:145)

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@PeterJohnson Now that I look at the API docs of those cscore methods, I see this warning:

   * <p>CameraServerJNI#setTelemetryPeriod() must be called for this to be valid (throws
   * VisionException if telemetry is not enabled).

It appears that this might be what's happening here, despite that method being called here, after loading the native libs, when the plugin is loaded:

shuffleboard/plugins/cameraserver/src/main/java/edu/wpi/first/shuffleboard/plugin/cameraserver/CameraServerPlugin.java

Line 57 in 69b2dc2

CameraServerJNI.setTelemetryPeriod(1.0);

Is it possible that one second isn't fast enough? What can cause this?

Originally posted by @Starlight220 in #773 (comment)