Why does VTEncoderXPCService take up all my cpu? 2010 Macbook Pro. Pretty frequently, my mac will spend over 100% cpu on VTEncoderXPCService. It causes the fan to spin up and it causes the computer to get hot. 

ps -ef | grep -i vtencoder


shows 

01   879     1   0 Mon10PM ??       261:54.85 /System/Library/Frameworks/VideoToolbox.framework/Versions/A/XPCServices/VTEncoderXPCService.xpc/Contents/MacOS/VTEncoderXPCService


which doesn't shed much light on the situation for me.

I'm not doing anything with video when this happens, either.

Any thoughts on what this is doing and/or how I can get it to not heat up my laptop so much?
It seems to be related to pulling movies out of Photos.  I had a large movie I was trying to take out of photos to a folder and move to an external drive.  This process was using over 300% of CPU for several minutes.