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View Full Version : [MeGUI] Yadif Problem: unsatisfying results

LeXXuz
13th October 2008, 03:39
Hi everybody. :)

I've come across some source material I have serious trouble with.

I've captured Stephen King's - The Stand via DVB-s which is, besides an awful noisy and blurry picture quality, interlaced.

When I feed this to the AVS creator in Megui, I'll get following script after analysing:


DGDecode_mpeg2source("D:\DVB-CAPS\STAND_P1\standp1.d2v",info=3)
ColorMatrix(hints=true,interlaced=true)
Load_Stdcall_Plugin("C:\Programme\megui\tools\yadif\yadif.dll")
Yadif(order=-1)


It seems that yadif is somewhat overstrained with this source. The resulting encode looks really bad in moving areas (extreme pixelation...).

Here is a screenshot of slightly moving scene:
http://img80.imageshack.us/img80/7659/standgc1.th.jpg (http://img80.imageshack.us/my.php?image=standgc1.jpg)http://img80.imageshack.us/images/thpix.gif (http://g.imageshack.us/thpix.php)

This screenshot is from an almost still scene:

http://img80.imageshack.us/img80/6401/stand2lk0.th.jpg (http://img80.imageshack.us/my.php?image=stand2lk0.jpg)http://img80.imageshack.us/images/thpix.gif (http://g.imageshack.us/thpix.php)

It's not a beauty either, but looks way better than the other scene...


Any suggestions for a better deint-filter? Or should I maybe denoise before deint?
Sharktooth
13th October 2008, 14:47
denoise filters should be always placed AFTER deinterlacing.
also, give your encode more bitrate.
LeXXuz
13th October 2008, 17:36
denoise filters should be always placed AFTER deinterlacing.
also, give your encode more bitrate.

I know. I just thought about making a progressive 50FPS source, denoising it and then using the deinterlacer.

It's hard to believe, but it is already a CRF20 encode. Like I said, the source quality is very poor...
Sharktooth
13th October 2008, 18:00
use the mpeg2 deblockig filter integrated in dgdecode.
LeXXuz
13th October 2008, 18:07
use the mpeg2 deblockig filter integrated in dgdecode.

Good call, totally forgot that one. I'll give it a try. Thx. :)
Didée
13th October 2008, 19:04
Could you post a short sample of such a scene with movement? Chances are the source is a fieldblended normconversion, in which case you don't need just a deinterlacer, but rather a restorer to revert the fieldblending ...
LeXXuz
13th October 2008, 19:14
Could you post a short sample of such a scene with movement? Chances are the source is a fieldblended normconversion, in which case you don't need just a deinterlacer, but rather a restorer to revert the fieldblending ...

Yeah, that rings a bell. Reminds me of Voyager, Simpsons and a lot of other poor NTSC->PAL transfers ... :mad:

I'll try to upload a short sample clip as soon as I got some free time. :)