decomb and 'half frames'

[actionman133]

Hi all.

I've been trying to clean up the poor telecine mastering of the BMW The Hire short film series... I'm sure many of you would be familiar with it.

Only decomb has a chance in hell of reversing the telecine process, because of the many pattern breaks etc. My main problem is there are many instances where only one field exists for a frame before the pattern breaks and resets on a shot change. In case that's poor wording, I mean:

a b b|a b ...
a b c|a b ...

In this situation, Decomb will remove c, and replace it with b, resulting in a lost frame, replaced by a duplicate of the frame before it.

What I want to do is recover frame c as much as possible with a smartbobber. Decomb can't do this as far as I know, so I've made my own script to do it. Can Decomb do this on it's own, or do I need to use this script?


LoadPlugin ("E:\AVISynth Plugins\Deinterlacing\Decomb 5.21.dll")
LoadPlugin ("E:\AVISynth Plugins\Deinterlacing\KernelDeint.dll")

First = Telecide (1, 1, post = 0, hints = false)
Second = Telecide (1, 1, post = 1, hints = false)
Test = Subtract (First, Second)

ConditionalFilter (Test, First, KernelDeint (0, 15), "IsCombed (1)", "=", "False")


First and Second will produce the same output, with exception of interlaced frames, in which Decomb will replace with the previous frame when post=1. ConditionalFilter picks up on that and returns the no longer lost frame with KernelDeint (field dominance is reversed to telecide's so that it recovers the 2nd field).

So can Decomb get me this lost field, or do I need to do this? If you want the sources, I can't upload on my dialup restrictions (working on getting broadband, but it's a long road ahead), but the films I'm testing this on are Ambush and Star of the The Hire series, so if you have that on DVD, you should be able to replicate the environment.

Thanks.

[GeneralMartok]

Try tritical's TIVTC (http://forum.doom9.org/showthread.php?s=&postid=618798#post618798) filter. It handles the orphaned fields problem better than Decomb.

[actionman133]

thanks, the forum makes it look promising... will let you know how it turns out.

[ArabianSwan]

or try the new YMC.exe "comes with yatta", it has TFM option ^_^

[MOmonster]

Have you ever seen such an example?
Not long time ago I tested really a lot of such bad telecined material. Over ten different sources, sometimes I get two different blends in one frame, no chance to restore this, but never I get such an example, three followed clear fields a,b,c. Never!
The only possibility to lost clear fields is for example if one frame has the fields A and B and the next has a blend BC and the field C. In this case we will lost the clear field B.
TFM doesn´t works better in this cases.
I hope this help you a little bit.
If you really have a source with such an example, please can you upload a short scene? (just some mb)

[scharfis_brain]

I've SEVERAL samples, which have orphaned fields

1) fielddropping NTSC -> PAL conversion
aa bb cc dd ee f ggg h iii j kkk l mm nn oo .....

2) fielddropping NTSC-FILM speedup (to be able to show more ads)
aa bbb cc ddd ee fff g hhh ii jjj kk ....

3) weird 25fps FILM (PAL) -> NTSC telecines

[actionman133]

My bandwidth is low atm, so I can't send it right now.

If you want another popular patternbreaking example, look at the Musical Journey DVD with the Revenge of the Sith soundtrack.

But it doesn't matter anyway. I developed a precise method of salvaging the fields... unfortunately it's manual.

For the BMW film Powder Keg (the longest and most frequently cut of the films), I ended up with a script that was 13 Kb, from 417 lines...

Took me a whole dedicated day...

[MOmonster]

@sharfis_brain
Before I did the test I also had the idea, that it could be that there is something like this aaa b ccc, why not, could be possible, but normaly there are five frames between the triples. In some strange conversations, sometimes less sometimes more but I see never only one field between this triples.
I get only such examples aaa b b/c cc. But of course maybe some weird material has also such conversations like you give me.

@actionman133
If I see such sources, I´ll have an eye on it. Thanks for your reply.
Maybe you can use doubleweave and then leakkerneldeint as postprocessor and then TDecimate or FDecimate for decimation.