30p to 50i while preserving "the look"

[2Bdecided]

This is kind of a rhetorical question, because my gut instinct is that it's impossible, but...

I have some 30fps (29.97 progressive) footage that I want to convert to "PAL".

I can use the mvflowfps(2) scripts to go to smooth 50fps and then re-interlace.

The problem is that the footage doesn't look the same. I hate to say this (because I usually hate "the film look" and love "the video look") but it's animation, and it just looks wrong as smooth 50i.

30fps doesn't judder like 24p-in-60i, is slightly smoother than 24fps native, but isn't really smooth like 60i.

So how can I preserve this look in 50i?


I thought about DGpulldown, but of course 30fps is already too many frames for 50i.

I used convertfps (EDIT: I mean ChangeFPS) in AVIsynth instead, and the result looks a bit juddery.

I'm almost thinking of going to 25fps via mvflowfps, but this seems silly - so slow, and artefacts seem more visible on pure progressive frames (slower frame rate may cause this too!).

Any ideas?

This is partly "for my own interest" since I think the best way to treat the content is to do nothing and watch it as "NTSC", except you never know when you might find a TV that doesn't like this. Plus the extra resolution of PAL (added via EEDI2) is quite nice.

Cheers,
David.

[halsboss]

I had NTSC stuff played on players (almost all, nowadays) which "converted" to play sort of OK on a PAL TV... so I understand your inclination to do nothing and watch it as "NTSC" and this would be an academic exercise.

[IanB]

Have you tried a simple ChangeFPS(50) + Interlacing.

And did you test both Blend and Switch mode with ConvertFPS(). Did you correctly tune the VBI value in switch mode? The visual effect is very critical as is correct field order.

MV with traditional animation is usually poor as the motion is unnatural. Modern CGI generated "true life" animation can give better result.

[2Bdecided]

Have you tried a simple ChangeFPS(50) + Interlacing. - sorry, my mistake - that's actually what I was using, which is juddery.

And did you test both Blend and Switch mode with ConvertFPS(). Did you correctly tune the VBI value in switch mode? The visual effect is very critical as is correct field order.I've never tried the VBI value - I should do. I didn't like the broken verticals on CRTs and unpredictability on everything else. I'll have another go though - thanks.

MV with traditional animation is usually poor as the motion is unnatural. Modern CGI generated "true life" animation can give better result.Luckily this has normal motion every frame. However, looking very carefully at it, I'm wondering if just maybe it was cleverly converted from 24fps - or it could just be the animation - some of the motion blur goes very "bitty", and it doesn't look like MPEG coding artefacts.

Cheers,
David.

[2Bdecided]

I had NTSC stuff played on players (almost all, nowadays) which "converted" to play sort of OK on a PAL TV... so I understand your inclination to and this would be an academic exercise.One of mine seems to repeat/drop fields to hit the required frame rate. Same as ChangeFPS, but without the nice fake resolution boost of EEDI2.

Where mine really chokes is on 24p content: it judders horribly, whereas a simple speed up to 25p in software makes everything great (except the audio ;) ).

Cheers,
David.

[Undead Sega]

30p is quite smooth to be honest, but i understand it wont be as smooth as 50i or 50p. i was myself looking for a technique for make a 25p to 50i, but thats all in the machinery, as it does that itself. correct me if im wrong on this.

u could always interpolate frames to 50p and make it 50i.

[Mug Funky]

my bet is on convertfps. it'll give a slight feeling of ghosting, but so long as your eyes aren't tracking objects and are just glued to the middle of the screen the results motion-wise should be visually the same.

it would be something like:

30psource...

filters...

your favourite resizer to 576 lines...

convertfps(50)

assumetff()
separatefields().selectevery(4,0,3).weave()
assumetff() # just in case