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Talayero
30th November 2006, 07:17
Hi,

I have a 29.97 fps USA documentary shot on video, progressive and TFF, that I want to convert to PAL using CCE

I know the conversion can't be perfect, being a progressive 29.97 fps source, but I don't mind. Most of the film are interviews, and there are not many motion scenes.

Another doubt I have is if I need to check the progressive and zig zag boxes in CCE and write also in the script ConvertToYUY2(), that's to say, if the resulting PAL must be progressive or interlaced. Anyway, if I'm not wrong, I should encode interlaced in order to keep video/audio the same lenght.

Thanks in advance.

Guest
30th November 2006, 08:16
I have a 29.97 fps USA documentary shot on video, progressive and TFF, that I want to convert to PAL using CCE

I know the conversion can't be perfect, being a progressive 29.97 fps source, but I don't mind. Most of the film are interviews, and there are not many motion scenes. Are you sure it's 29.97 progressive? That's unusual.

Assuming it is progressive, then since the motion is not important, you can try this for the rate conversion:

FDecimate(25)

Another doubt I have is if I need to check the progressive and zig zag boxes in CCE

Use progressive and zig zag scan.

and write also in the script ConvertToYUY2() It's not needed for CCE.

if the resulting PAL must be progressive or interlaced. It will be progressive.

Anyway, if I'm not wrong, I should encode interlaced in order to keep video/audio the same lenght. No, that has nothing to do with the video length.

foxyshadis
30th November 2006, 08:45
FDecimate will do fast, decent work on talking heads, but might cause some mild skipping/desync on actiony parts. If you want to remove all judder, at cost of long encoding time, you can check out this thread's tools:
http://forum.doom9.org/showthread.php?t=113256

Then again, if it was a budget docu, it might have a fair bit of skipping/desync already.

Talayero
30th November 2006, 08:53
Thanks.
Do you mean that's all I need?:

LoadPlugin("D:\DGDecode.dll")
Mpeg2Source("D:\movie.d2v")
LanczosResize(720,576)
FDecimate(25)

And yes, I know it's unusual but is 29.97 progressive, without any doubt.

2Bdecided
30th November 2006, 11:32
How do you intend to watch the result? If it's on a progressive display, then there's an argument for staying progressive, but...

Without getting into slow mv/mc conversions, the smoothest quick conversion of 29.97 progressive content into 25fps will be to interlaced. e.g.


AssumeTFF()
LanczosResize(720,576)
changefps(50)
separatefields()
selectevery(4,0,3)
weave


You won't lose any of the original frames that way. Some will appear in two fields of the output, others in just one. Whether this is preferable to dropping frames entirely to get down to 25fps is probably subjective.

If you use converttoYUY2().convertfps(50) (you need the colour conversion for convertfps to work) you'll get field blends in the output, rather than a choppy but clean 2-1 pattern of field repeats. IMO this looks horrible during PC playback, but successfully smoothes the motion somewhat on a CRT TV compared to straight changefps(50).

In order to easily encode the 30fps progressive output from my digital still camera for use on a PAL DVD for watching on a CRT TV, I use
convertfps(50)
lanczosresize(704,576)
assumetff().separatefields().selectevery(4,0,3).weave()

and I am quite happy with it.

Mo-comped is sometimes better (though on some content it doesn’t matter, and on some content it gives visible artefacts), but oh so much slower!

Hope this helps.

Cheers,
David.

Guest
30th November 2006, 15:35
Thanks.
Do you mean that's all I need?:

LoadPlugin("D:\DGDecode.dll")
Mpeg2Source("D:\movie.d2v")
LanczosResize(720,576)
FDecimate(25)
It will be a bit faster if you reverse the last two lines.

Chainmax
30th November 2006, 15:59
...
and write also in the script ConvertToYUY2()
...

It's not needed for CCE.


So it's needed only for interlaced content?

Hilfert
2nd December 2006, 02:04
I have never converted 29.97fps NTSC -> 25fps PAL, but I sometimes convert 23.976fps NTSC (progressive) -> 25fps PAL using AssumeFPS(25) in avisynth.

This will change the length of the clip so audio needs fixing too. I use besweet with switch soundtouch (and -r) to change the tempo, but not the pitch. TimeStretch in avisynth should be able to do the same, but I've never tried that.

As long as the pitch is unchanged I've never noticed the clips playing at a different speed, but in your case the difference is larger so perhaps it's unacceptable somehow.

Talayero
2nd December 2006, 15:25
Hi,
I finally used this script for my movie conversion from 29.97 fps (progressive) ----> 25 fps PAL (interlaced)
It's the script 2bdecided suggested:

LoadPlugin("D:\DGDecode.dll")
Mpeg2Source("movie.d2v")
AssumeTFF()
LanczosResize(720,576)
changefps(50)
separatefields()
selectevery(4,0,3)
weave()

It went very well. Same lenght, and I didn't notice any jerks when watching the converted dvd.

I don't know if it's worth the while to try something different.
I assume also that I didn't misinterpret the source characteristics. DGIndex said 29.97 fps, 100%video, and progressive. Besides I opened the script in VDubMod and checked that every frame were progressive. So, there's no doubt at all, I think.

I wonder how you can call such a movie. It's not soft telecined, and it's not hard telecined either, I think. I't's a film -a documentary, actually- that was shot with a videocamara that can shoot 29.97 fps progressive. Then they authored that mpeg2 into a ntsc dvd and that's all, isn't it?

Mug Funky
5th December 2006, 02:21
i've seen some skiing/snowboard docos shot this way, but usually they're spliced with stuff shot on 16mm and stuff in 60i. it's a bit of a mix...

there's also stuff out there that's been shot in 60i and deinterlaced... giving 240 lines of actual video. who knows whether they're going for the "film look" or the "youtube look" with that kind of treatment :)