29.97 interlaced to 30p using Andrew Kramer’s frame rate converter

[Kevin Camp]

i wouldn’t use andrew’s frc for this.

just select the footage in the project window and choose file>interpret footage>main. in the interpret footage settings make sure that the separate fields option is set correctly for your field order (often lower field first for ntsc) and also check the option for preserve edges.

if you do in fact need 30 fps (not 29.97 fps) you can change the frame rate in that window to, just note that since 30 fps is not a standard frame rate, you will not be able to go to tape, dvd, blue ray or any broadcast destination, but if that’s not your final destination, then 30 fps is fine.

after that you can drop the footage on the make comp icon and view it. if the motion seems just a bit stuttery, this is due to the fact that now the footage is effectively half the original shutter speed, so there is less motion blur. try enabling frame blending (frame mix) for the footage and turn on frame blending for preview to see if that helps.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Clyde Villegas]

Will it affect the “timing” of the footage? Don’t you think it will affect the length of the video, like being longer (or shorter) than the original footage? How about the speed, will it be the same as the original footage?

ut in omnibus glorificetur Deus

[Kevin Camp]

it will be off 3 frames for every 100 frames, but it shouldn’t matter too much if everything else is 30 fps, everything should match up.

there are two advantages to making slight speed adjustments this way… one, it renders much faster; two, the image quality and smoothness of motion is much higher. you get all the original frames, and the original frames will look better than any interpolated frames. plus the motion will be as smooth as the original, often with frame rate conversion will see a hitch even with interpolated new frames.

also, i’m not sure ryan really needed to convert 29.97 to 30 fps, i’m not sure what you’d need 30 fps for? if all he needed was 30i to 30p, then making sure that ae was separating fields is an easy way to go, but there are other plugins that can do a better job de-interlacing, like revision’s fields kit, but it’s not free.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Ryan Santos]

Thanks guys! Is there a cheaper alternative (free is better;-) ) than revision’s fields kit?

[Kevin Camp]

i don’t know of a deinterlacing effect that is cheaper than fields kit off the top of my head… note, fields kit is just a deinterlacer, it does not adjust the frame rate…

i doubt any others are free, since ae will deinterlace right out of the box. i do think that if you set ae to separate fields, then enable frame blending (frame mix) for the footage, you’ll be quite happy with the result.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW