Frame blending and duplicate frames

[loekverhees]

Hello,

I got this video from the official Avatar Movie website. The problem is that the video does not play smoothly. I imported the video in AVSEdit and applied the SeparateFields() command. Then I exported it using x264 in VirtualDub (see the sample in the attachment). When I watch the video frame by frame, some frames are blended and some frames are kind of double. What is the proper way to IVTC (I don't know whether this is the right term or not) this using avisynth?

Sample: Here (http://forum.videohelp.com/images/guides/p2036823/sample2.avi)

The final destination for the video is supposed to be DVD.

[Guest]

Post the link to the video you downloaded.

[loekverhees]

This is the link: Link (http://youtube.com/get_video?video_id=Ti_LqksDgZQ&t=vjVQa1PpcFM1cBLnDMiKDvfdxRRuZ6aRwzN12O7IcN0%3D&fmt=22) (for download) and Link (http://www.youtube.com/watch?v=Ti_LqksDgZQ&feature=PlayList&p=4B35A107A9EFC654&playnext=1&playnext_from=PL&index=26) (for the webpage).

[Guest]

Those are YouTube links. What is the URL at the Avatar web site that you mentioned?

[loekverhees]

The URL of the website is http://www.avatarmovie.com/index.html. But I can't give the URL of the video on that website because it's all flash I think (the URL is still exactly the same). You can select the videos button on the strip on the lower side of the webpage. Then there are links to YouTube when you hover over the video with your mouse. After that, I downloaded the file from the YouTube website.

[Guest]

So you're asking how to fix up a crappy YouTube video trailer? What's the point?

[loekverhees]

It's not the usual youtube crap like it was some years ago. It's because since youtube quality is becoming better these days (there are some really neat HD video's out there) I thought maybe it's possible to fix them these days.

I know that if the source is very bad, it's impossible to repair it. But I don't see why sometimes it's possible to repair a DVD (which has problems like frame blending and double frames), and that it is impossible to repair a youtube video with the same problems, as you say.

What's the point?
I'm trying to put ~15 minutes of background footage on a DVD (like 'the making of' and interviews and all that stuff) and just wanted to try to clean it up a bit.

[Guest]

Use the original DVD as the source.

[loekverhees]

Ok, that's possible (if that footage is on the DVD of course when it comes out).

The youtube video is progressive, is that the reason why it can't be repaired?

[aegisofrime]

Ok, that's possible (if that footage is on the DVD of course when it comes out).

The youtube video is progressive, is that the reason why it can't be repaired?

Nothing wrong with progressive. It's just that garbage in ---> garbage out. It's just a waste of effort fixing a crappy flash video when you can use a much better source.

[loekverhees]

For me, it's not so much about the final result, it's more about the process that leads to the result. To learn the steps. The youtube video was more sort of an example to play around with, because I've never worked with youtube videos before.

[thetoof]

http://forum.doom9.org/showthread.php?t=134078

[loekverhees]

@ thetoof: thanks for the link, however that topic is about low quality youtube videos (with lots of compression artefacts etc.), but the video I'm talking about only has temporal problems, the spatial quality is just fine.

[thetoof]

fubar

the source was badly brought to 23.976 and the blends are impossible to restore:
-right section - blends look like some kind of motion blur when the dragons are flying; since there are multiple blends in a row = impossible to "recover"
-left section - blends everywhere... looks like 30i DV footage that was blend deinterlaced and then brutally decimated to 23.976

What I did on your sample2.avi:
assumefieldbased()
weave()
bob()
tdecimate(1,3,5)
After weave, your clip looks phase-shifted and telecined. You could try tweaking tfm to match everything properly instead of bobbing as I did (didn't want to take the time to test and tweak). This line used in another thread on Eureka 7 already helps a bit tfm(cthresh=6,MI=32,pp=0,mmsco=false,micmatching=3)
That being said... crap in - crap out. Spatially and temporally.

[loekverhees]

Thanks for your answer, thetoof.

I discovered that the original video (not the sample2.avi [ where I used SeparateFields() ], had a pattern of 5 frames where two of the 5 frames were identical. However, that pattern was not the same throughout the entire video. In the beginning it was like ABCCD ABCCD etc. So I used SelectEvery(5,0,1,2,4). But this order keeps changing in the video.

Is there some way AviSynth could detect two successive identical frames and delete one of them automatically?

Edit: I discovered that tdecimate(), like thetoof already said, does exactly that. It plays back much smoother now! Though I don't know what the difference is between tdecimate() and tdecimate(1,1,5). I looked it up in the documentation, but did not really understand the difference between mode 0 and 1.