Filtering and motion detection

[fberreth]

I hope this is not too off-topic and that this was not suggested before (at least not too often) but when I read about all those spatial and temporal filters and the problems they have - I think the best motion detection after all is in the encoder. When it chooses a macroblock X from the previous frame to be placed in the current frame - information like this is highly valuable for filters and maybe it would be a good idea to have a plugin right there. Just an idea.
Maybe I'm just nuts - sorry. After all I don't know too much about MPEG encoding & filters but you devs that are listening here do.