[fritsch]

There is content that is sadly not progressive completely, but mixed with interlaced stuff, which one cannot auto detect. Therefore there is an option for the user to force it on. It can change per spec. Especially TV in great britain has such streams.

I cannot do more than: Give a straight howto, which clearly in fat / bold says: Don't force deinterlace to On ...

I can explain things to you - but I can't understand them for you.