Thanks for the catch on cropping! I think I got those 72 values by working with a PAL source, and forgot to change them for NTSC...

Yeah, I hate having to do the convertto's, but tempgaussmc_beta1() only works in yv12, and I really like its deinterlacing results. Deinterlacing/interpolated scale/reinterlacing seems to produce a less aliased image than the basic script, which IMO looks better, but yes, it certainly makes things a lot more complicated (and slower) than just scaling the image.

EDIT: Wait, I think I got what you were saying about having the full frame and not messing with the fields. I thought crappy old 4:3 letterboxed DVDs would be hard-telecined, but maybe they just have the pulldown flag just like modern DVDs... I'll try the whole process without deinterlacing/interlacing, but still using the interpolated scale, and report back.