Deinterlacer:
Allow setting different deinterlacing algorithm method for interlaced footage on rendering.
I think you don’t have to choose anything if you use progressive video material.
And: Render full colour range … if you need 10-bit color instead of 8-bit color. Please note that this does not work with effects (yet).
I think normally do not use it.
A big compliment to those who wrote the Kdenlive manual.