Use dupe frames to help denoise 720p

[Emp3r0r]

I have some 720p material here that is AABBBAABBBAA which is film with duplicate frames to make 60 fps. I've noticed the noise is different between duplicate frames.

How can I denoise this material using the duplicate frames to my advantage before throwing them away?

[Mug Funky]

use temporalsoften with a very very low scenechange threshold (i wish this was a float value, as sometimes "1" is too high).

something like:

temporalsoften(1,32,32,1)

there's much cleverer ways to do it, but they're slow and i can't be bothered scripting one just now :)

[foxyshadis]

dup(threshold=.4,chroma=false,maxcopies=3,copy=true,blend=true)

Play with threshold depending on how much noise there is, and maxcopies if you have longer sections. This will blend every run of dup-ish frames into a run of perfect duplicates.

[Emp3r0r]

That didn't really help much. I'm uploading an example file to help with choosing the deniose script. I've been playing with some filters but havn't gotten anywhere.

I remember long ago someone on the forum was capturing a source twice and using both captures to create a cleaner capture. I think the principle is the same here.

I found this which could be helpful with getting rid of the ugly scenechanges.
http://forum.doom9.org/showthread.php?t=78338

example file: http://jvance.com/files/wotw.zip

[Mug Funky]

well, if there's any difference between the dupes on a 720p encode, they can't be analog noise. this means they're mpeg artefacts... averaging them can help, but it's also likely to bugger things up - it'll average bad frames with good.

we need some quick metric for detecting if a frame is "blocky" or not. or perhaps frames could be de-blocked then averaged?

[Emp3r0r]

i used cpu=4 in the mpegdecoder and tried using UnDot().FFT3DFilter(Sigma=3,BW=16,BH=16).Deen("c3d",1,3,3,25) after droping the duplicate frames. It helped a little bit but I think i need break out the dvd as I think it has less noise. However, the DVD has some very sad quality for a newer release movie.

[Pookie]

Very common on some 720P material. For the sake of time, I'll usually do a SelectEven and/or SelectOdd, scrub through see if one looks better.

I posted a similar question back last summer. A kind soul had a function that helped; my impatience ultimately led me to use the option above.

[Emp3r0r]

I dropped the FFT3DFilter as it was adding way too much ringing. As for the dropping of the duplicate frames I used selectevery(5,2,4) which is working pretty well. It seems to avoid the ugly scene change frames because it has a whole duplicate frame to catch up.

[Pookie]

Whoops. Just took a look at your source file. Forget what I wrote, I didn't realize the extent of your blocking. That's bad enough just to consider getting the standard def version of that movie.

[Emp3r0r]

i already own the dvd, however i had one look at it and wish I could have got my money back. alas, it has very poor video quality. overall, if I can avoid those rare ugly scenechange frames, this version is better than my dvd.

[wheelbit]

So if you wanted to convert this AABBBAABBBAA material back to 24 fps how exactly would one do it? I have a similar source and Im not sure how to convert it back to 24 fps.

Thanks,
wheel

[foxyshadis]

For AABBAABBAA..., decimate(mode=2) or tdecimate(mode=1).

For ABABA..., tdecimate(mode=1,cycleR=3).

[wheelbit]

The pattern is AABBBAABBB, not AABBAABB nor ABABA, ect.

[foxyshadis]

I meant what you want to end up with, starting from AABBBAA..., sorry about that.

[DryFire]

what about throwing in TTempSmooth?