I just did finishing work on an independent DV feature that was shot in 24pA. Due to camera operator error, about 30% of the footage was shot as 29.97i, a pretty major screw-up. The editor had tried to convert the 29.97i to 24p using Magic Bullet in After Effects, and the results were simply awful. I was pretty sure that I could get better results using Compressor, so I did a few test clips.
To my astonishment, the Compressor-converted clips looked AMAZING, as if they had always been 24p. Out of around 60 clips, only one or two had slight artifacts that were only visible on very close inspection. I ended up batch converting all of the 29.97i footage to 24p using Compressor, and the client was ecstatic. The converted clips match the native 24p clips perfectly – no one would ever know the difference from watching the film.
The optical flow / motion estimation technology that Apple inherited form Shake works wonders in Compressor for format conversions. The devil is in the details – Frame controls need to be turned on in the inspector tab, and there are specific settings to use for the best results. It’s too lengthy to go through them all in this post, but feel free to PM me if you need assistance.
Compressor can’t make SD footage look as good as HD when scaling it up, but when it comes to conforming all of your source footage to a uniform frame rate, it works extremely well. Maybe not Teranex quality, but quite usable nonetheless. You may want to show 4:3 SD footage pillarboxed (black bars on the sides) to avoid the further degradation of scaling it up to fit the 16:9 frame.