Deoldify Vapoursynth filter

[Selur]

Since you are the only one out there who knows how to use it, I need feedback on what to change so that:
a. one can enable the option without the preview or the encoding crashing
b. one can not set stuff that causes crashes. If one specifies to demanding settings for one's hardware that is 'okay' to crash. But enabling feature X should always create correct calls.

Cu Selur