Which is better, Vegas 6 (60i to 24p) or DVFilmakers 60i to 24p?
 

I read here that Vegas 6's 24p conversion from 60i looks really good. Does it look close to the 24p cams (DVX-100/XL-2). Or does DVFilmaker do a better job?

James, let's get technical. Does anyone know what method Vegas uses to convert to 24p? This thread would indicate that it's throwing away 60% of the fields and interpolating based on the remaining fields. That sounds extreme, I'm not sure I can believe that.

Another thread said it does a basic inverse telecine (IVTC). That means it throws out 20% of the fields and possibly deinterlaces the remaining fields, either through interpolation or field blending (sounds like it's configurable).

Does anyone have a better reference for how it works?

IVTC will look fine for NTSC playback, but it's not for film out.

Josh

Whatever it's doing, it does do damn good job of it.

I have both DVFilm and Vegas 6. Up until Vegas 6 I would have said DVFilm did a better job, but Vegas 6 does what to my eyes looks like a perfect 60i to 24p. They've changed the frame rate conversion algorythm. I've posted questions on the Sony site several times asking how it works, but the question has been ignored each time. I suspect that they're treating 60i like 60p then dropping frames from this in something based on a 3:2:2:3 pattern but I'm not sure. Whatever it is, it really looks good.

By the way, PAL conversion is equally good too now. So does uprezzing interlaced video.

*removed* doh!

Thanks for posting the clip. If you look at the upright poles about 60% through the clip, and advance frame by frame, you will see that there is a double image, a double image, then a triple image, a triple image, etc. So, it's definitely doing some frame blending, I would say. Slight double images can occur in DVFilm Maker, but I've never seen a triple image. Interesting. If it was interpolating, there would be a single image. MB would give you a single image. It would also probably strobe badly on this clip. The blending tends to smooth the strobing out.

It's an interesting pattern, though, I can't figure it out exactly. There should be a test clip for 60i to 24p conversion that will help you figure out what's going on.

Josh

I downloaded the clip and stepping through it frame by frame, I can see what you're talking about. Then I went through one of my own conversions frame by frame and it was perfect.

I don't know why our results are different.

Lawrence, I believe there are at least two modes, from the previous threads I read: interpolation and blending. He's probably using blending, you're probably using interpolation. There are circumstances where one is better than another.

There were two modes (interpolation or blending) which affected 24p renders on Vegas 5 and before. In Vegas 6, neither one is used on a 60i to 24p render. In looking at his file again, It looks like he might have rendered to 24p instead of 23.97 which meant that it couldn't use a 3:2:2:3 pulldown perfectly.

*edit*

checking something...

Ok, couldn't be sure if I originally exported that last clip under Vegas 5 or 6 (just got my upgrade last week and that ghetto footage is from last week and I don't remember).


Anyway, here's a new clip, just captured it off tape now, just exported it now (straight from Vegas to Quicktime). 23.976, Interpolate fields, etc etc.

Click

Hope that's a better indication of 24p under Vegas. I still see a 2-3 ish type of cadence when looking at the light poles, but all in all, it's pretty good to my eyes. No stuttering. Nothing looks wrong, etc.

Patrick, yeh, definitely blending. It won't produce accurate and crisp stills, but it'll look pretty smooth on NTSC playback. Due to the multiple (and changing effects on some objects, it's probably not suitable for film out, but who of us is actually ever going to do a film out?

Would you be game to grab the demo version of DVFilm Maker, and convert the same clip? I'd be interested to see a side by side.

Vegas 6

DVFilm Maker

For DVFilm, I used the "24P Editing Options -> Convert 60i to 24P" option. Reimported back into Vegas and saved back to Quicktime.

I dunno, to me, I actually think the Vegas 6 footage looks better, or to my eyes, what I would expect to see. The blurring between frames looks a lot better and more even over time, like actual motion blur (sort of) between frames - DVFilm is very staccato, then blurred, then staccato, etc - feels a lot more mathmatical than naturalalistic.

$.02

Patrick, awesome, thanks for posting those!

Yeh, with DVFilm Maker, it samples every 2.5 fields. So odd number frames are based on those half fields, where it sample backwards and forwards, and there is a slight double image. You get single/double/single/double.

Vegas you're getting double/triple/double/triple. Vegas must be blending, not just two fields, but three in some cases. The extra blending actually gives surfaces a very smooth appearance. Grain gets averaged out and its very smooth.

I'm a little bothered by the double/triple cadence. The lampposts, in particular, look very strange, because when they triple, they looks very fat.

I guess it goes without saying that the same scene, shot on film would have a single blurred lamppost in each frame.

Next step, Magic Bullet. You'll find with that each frame is interpolated and there won't be double images either. A single lamppost. It's actually so sharp in my tests that it gets very stroby.