Framerates of interlaced footage

[CursedLemon]

Having a hard time phrasing this question. I have some ripped DVDs that I want to convert to deinterlaced H.265 transcodes, but it occurred to me that I don't really know what framerate to rip them at. They're all at 29.97 as interlaced files, but some of them might be 24FPS material for example (when they're 60FPS it's fairly obvious). How do I go about converting these files so that I match the framerate?

[jagabo]

You perform an inverse telecine to restore the original 23.976 fps progressive film frames. In AviSynth it's TFM().TDecimate(). In Handbrake it's Deinterlace -> Decomb, and set the frame rate to 23.976. But there can be many possible complications...

[CursedLemon]

Is there any way to definitively tell if footage is 23.976 vs 29.97? Sometimes it's hard for my eyes to discern, especially with animation.

[manono]

With animations, yes, it can be difficult. But they always have places with scrolls or pans - where there's movement every frame. Then you look to see if every frame is interlaced or if there's the telltale 3 progressive and 2 interlaced frames in every 5-frame sequence. The 3/2 sequences tell you to IVTC back to 23.976fps.

Anyway, animations are never pure interlace (with sometimes some exceptions, such as end credits) and the intended framerate is most often 23.976, although there might sometimes be some real 29.97fps sections. You could always post samples until you get the hang of it. And there can be other complications as well, such poor PAL2NTSC conversions.

" I don't really know what framerate to rip them at."

"Rip" means to decrypt to the hard drive. Thus, they'll be "ripped" at the original 29.97fps. You probably mean to say 'convert' or 'reencode'.