VTDecoderXPCService taking CPU

Sometimes I notice CPU load for no reason and I see in Activity Monitor that VTDecoderXPCService is using 15-30% of CPU.

After I restart Safari it is ok for some time until it happens again.

Any ideas? Could be flash related? When this happens there is no videos loaded in tabs but maybe one play triggers the problem.

Should I just uninstall Flash from the system? I'm still on Mavericks and Safari 7 - will youtube play without issues via HTML5? I heard they made it work on Safari 8, not sure about 7.

Thank you