Exception on Removal of Gpu Operation

[TheTripleV]

Steps to Reproduce:

1. Add a webcam/video source
2. Make it visible
3. Add a blur operation (I just left it at box blur)
4. Connect the blur's input to the source
5. Make the blur visible
6. Set the blur to gpu preferred
7. Remove the blur
8. Exception occurs

Thread[JavaFX Application Thread,5,main] threw an exception

Stack Trace:

java.lang.NullPointerException: This pointer address is NULL.
	at org.bytedeco.javacpp.opencv_core$Mat.channels(Native Method)
	at edu.wpi.grip.ui.util.ImageConverter.convert(ImageConverter.java:58)
	at edu.wpi.grip.ui.preview.ImageSocketPreviewView.lambda$convertImage$0(ImageSocketPreviewView.java:32)
	at edu.wpi.grip.ui.util.GripPlatform.lambda$onJavaFXRunnerEvent$0(GripPlatform.java:74)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:428)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:427)
	at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
	at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
	at com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:174)
	at java.base/java.lang.Thread.run(Thread.java:834)

System Info:

Property Name	Property
GRIP Version	v1.5.2-44-g37733eae3-cuda
java.version	11.0.2
javafx.version	11
os.name	Windows 10
os.version	10.0
os.arch	amd64

os.build | 1903 | 18362.113 cuda.version | 10.0.130 (2018/8/25)

[SamCarlberg]

That's pretty weird, I've never seen that happen. I'll look into it when I'm next using Windows.