Aliasing Problem Driving Me Nuts

[joe55]

Hi, Mabye someone could help me out, this has been driving me nuts trying to find out the cause of this aliasing, the DVD looks fine, no aliasing at all, the xvid I ended up with is 23.976/576x416/1150kbps ..I used Forced Film in DGIndex/Kernel Deinterlace to get rid of the interlacing..no extras or anything in avisynth (I am using Gordian Knot) The movie looks great except certain things like around peoples glasses the frames have aliasing problems and other small things that catch your eye, here's a screenshot:

http://img369.imageshack.us/img369/3698/aliasinghg5.jpg

On the top and bottom of the book it shows up and on her reading glasses. Is there a filter I have to add to avisynth to get rid of this, I'm completely lost and would like to know how to fix this, thanks for any help :)

[Blue_MiSfit]

you shouldn't be using both force film and a deinterlacer.

The whole point of force film is to bypass pulldown, so that the true 23.976 fps progressive MPEG-2 (What's actually on the DVD) gets decoded unaffected.

Let's make sure your DVD is actually film. Re-load the VOBs into DGIndex, disable force film (obey pulldown), start a preview, and let it run for a couple minutes. What does frame type and video type say?

If it's film and a high percentage, then definitely enable force film, and DONT deinterlace.

If it says video, then you have true interlaced MPEG-2, and you should NOT enable force film, and DO deinterlace - by any method you see fit, I like TDeint personally.

~MiSfit

[foxyshadis]

Well, 100% video can mean either hard-telecine or true interlaced (or worse, both). You still have to test it manually, by stepping through separatefields() to find matching fields. 2-2-2-... is field-shifted progressive, 2-2-2-3-3 is telecine, nothing perfectly matching is true interlaced, and anything else is a good way to mess up your day.

[Blue_MiSfit]

Indeed. Forgot to mention hard telecine :)

~MiSfit

[joe55]

Okay, thanks for the info everyone. I am getting close it seems, I was reading a lot today about that telecide/decomb/Decimate ..so in DGIndex now I just set the Field Operation to "Ignore Pulldown Flags" ..then in my Avisynth I have "Telecide(order=1,guide=1).Decimate()"

I just encoded a 2 minute clip and here's the screenshot:

http://img375.imageshack.us/my.php?image=newlx8.jpg

It looks perfect now, the aliasing is gone, but during the clip there is still interlacing you can see. I just need to get rid of this interlacing now and it should be fine, I think I read somewhere I can use kernel deinterlace with Telecide?

The video I just made is running at 23.976fps. I am in the right direction? Thanks for any more help!

[Blue_MiSfit]

still images don't really help :)

Cut a piece of the original M2V, and upload it somewhere. We can analyze it and advise you further.

Also, do as I suggested, and tell us what DGIndex says :)

~MiSfit

[joe55]

So in DGIndex set it to "Honor Pulldown Flags" let it run for a couple minutes and I'll take a screenshot of the Information bar of all the specs, correct? That M2V, where do I get that?

Thanks!

[foxyshadis]

Ignore Pulldown Flags is mainly a debugging option, you run a strong risk of breaking audio/video sync if you use it.

To get an m2v, mark a short segment with [ and ], then use save project and demux video, uploading the result.

[joe55]

Okay, one other thing, I've been trying "kernel deinterlace" all this time pretty much because that's what I've always used and had good results with other videos, so I just now I tried "TomsMoComp" and the aliasing is gone and it looks fine from what I can tell, I'm just encoding the movie now and I'll check back in a bit. Thanks!

[Blue_MiSfit]

There's lots of different deinterlacers, and they all have different algorithms.

TomsMoComp is a good one, I personally like TDeint a lot, when I cant afford to use MVBob and encode at 1fps :)

~MiSfit