30.00 fps progressive to dvd compliant 29.97 help

[Adub]

Hey all!

I am working on a small dvd project for my mother (and her warm memories). She bought one of those newfangled Flip Video (the SD version) and the damn thing puts out 30fps progressive.

Note: I don't mean 29.97p, I mean 30.00000000fps progressive scan.

What would you guys recommend I do to reduce the framerate down to 29.97? Obviously I am trying to prevent jerkiness and everything else.

I was thinking mvflowfps(2). Anyone agree/have a better idea?

[Dark Shikari]

Why not just AssumeFPS and resample the audio accordingly?

[Adub]

That's why I posted. I don't mess with framerates a lot, so I didn't even know that that option existed. I am taking a look that the timestretch() and assumesamplerate() functions now that you have mentioned it.

Edit: okay, what do you guys think of this example script?


#My 30.000 fps progressive video
assumefps(30000/1001, sync_audio=false) #disable audio syncro because it messes with pitch, which is properly handled by timestretch()
timestretch(rate=47952.047952047952047952047952048, quickseek=false) #48000 / 1001

[Guest]

Simpler would be:

FDecimate(29.97)

with no need to touch the audio.

[Adub]

Alright, that works for me. Thanks neuron2, for both the advice and writing the plugin.

[Guest]

Basically the method just drops a frame every 1001 frames. Theoretically, there may be a small jerk every ~30 seconds, but with that kind of source it's not likely to be objectionable. If it is, then Dark's approach would be indicated.

You could also use ConvertFPS(). The advantage of FDecimate() is that it will preferentially remove duplicate frames if possible.

[IanB]

Geeeeze, just do this.#My 30.000 fps progressive video
Ar=AudioRate()
AssumeFPS(30000, 1001, sync_audio=True)
ResampleAudio(Ar)I defy you to detect the change in pitch even using the beat of a tuning fork (the beat period will be 1001 seconds, i.e. 16+ minutes) If you warm a tuning fork up in your pocket that will cause more change than this.

[Adub]

Okay, that works too. I decided to just go with neuron2's suggestion, just to get the damn video encoded, and it looks and sounds just fine. I will keep your way in mind for the future though IanB. The only reason I was worried about the pitch is because I am a quality freak. Doesn't even have to be perceptible quality. ;)

Ah, well, this works just fine. Thanks everyone for your responses.