Mouth Movement Causes Horizontal Lines

[HartleySan]

Anyone else ever had this? I only get the problem with cartoons and never with live action. Basically, when there's rapid movement (generally mouths moving) I get these weird horizontal lines around the area that's moving quickly. Also, it's something that's most definitely not in the source. I've specifically been having problems with Aqua Teen Hunger Force. Anyway, I'm using Gordian Knot, but if anyone can recommend a good Avisynth filter to fix the problem, etc., that'd be very much appreciated. Thank you.

[Dark Shikari]

It is in the source; the source is telecined. You're not properly reversing the telecine (IVTCing).

[MadRat]

When TV first started out, engineers discovered they could do a better job broadcasting signal if didn't send the entire picture all at once. Let's say that the American TV signal is a picture that equals 648 by 486. The entire 648 pixel width of the picture is sent but first only the odd rows of the 486 pixel height is sent (1, 3, 5, 7, 9, 11...487). Then while those rows are still on the screen only the even rows are sent (2, 4, 6, 8, 10...486). That's called interlaced video or i. There's another method called progressive or p where you still display the 648 pixel width but this time you show the rows in order (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11...486).

Your computer screen is progressive so you can see the interlacing as lines that look like the teeth on a comb so sometimes this is called combing. If all this wasn't bad enough film frame rate is slower than American TV video frame rate. So a movie at about 24 frames per second has to be sped up to about 30 frames per second for TV and...it has to look like it's not fast forwarded. To do this they use a process called Telecine to merge some of the frames together using interlacing. Even if you get all the frames deinterlaced you'll still be stuck with 5 extra frames per second that have to be removed or decimated. The whole deinterlace/decimate process is called InVerse TeleCine or IVTC.

You could try just putting this into your script...


deint = TDeint(order=1, mode=2, mtnmode=3, blim=100)
TFM(order=1, cthresh=4, slow=2, clip2=deint)
TDecimate()


but it may not work. Sometimes the interlacing is set up so that instead of displaying the odd lines first (top frame first/TFF) they show the even lines first (bottom frame first/BFF). There are a couple of links that might help...

http://www.animemusicvideos.org/guides/avtechbeta/interlaceremoval.html
http://www.animemusicvideos.org/guides/avtechbeta/progressive.html