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plane
18th August 2006, 19:10
I'm not that familiar with Avisynth. I use it to do post-processing in ffdshow mainly but not video editing. Personally, I hate jaggy and interlaced so much.

http://forum.doom9.org/showthread.php?t=82787&highlight=mpeg2
The method mentioned in this post(reinterpolate420 - eliminate chroma jaggyness of PAL-DV) seems not helpful to another jaggy problem related to all video materials including MPEG2. That method is used to fix the well-known CUE(Chroma Upsampling Error) and it actually happens in many DVD players too, except the most high-end ones.

http://www.hometheaterhifi.com/volume_8_2/dvd-benchmark-special-report-chroma-bug-4-2001.html
To my best understanding, CUE can be appeared during in two situation. One is decoder upsampled the output to YUY2(4:2:2) from YV12(4:2:0) incorrectly(not only DV codecs do that, DVD Players do it too) and the other one is deinterlacing the Film DVD by wrong deinterlace algorithm and hence, made the chroma arrangement ugly because it used algorithm like BoB/Blend/Motion-adaptive to deinterlace the Film DVD, which ignored the progressive_frame_flag in the MPEG2 data(should use Weave to deinterlace Film DVD).

Even though we corrected the two problems above, we still have the last jaggy thing called ICP(Interlaced Chroma Problem) simply because the CrCb has too low resolution at interlaced 4:2:0 and the image is fundamentally broken up. Now, if I want to fix this last problem, could Avisynth or other software help me? Decode or Encode.

http://www.av-outlet.com/en-us/dept_335.html
I know there are some ways out there but they just not designed for PAL DV or accessible to me. Some expensive DVD Players, external scalers or HDTVs do equiped with a decoding technology so-called DCDi to fix it.

http://www.creativecow.net/articles/onneweer_barend/mb_review/
The greenshrinksoftware Magic Bullet Suite got a deartifacting feature(for encoding) but it doesn't support PAL(4:2:0).

Furthermore, any body know about PAL Broadcast Safe Colours? Again, the one build-in MB doesn't support PAL. I have had tried to find out through google search but they are mostly talk with NTSC and not much useful PAL information though.

Okay, stop to talk about jaggy and here is my workflow, see if there are any room to improve....
1. Use VD to load the PAL DV file(with MainConcept codec 2.4.4)
2. Convert it to the Lossless compressed HuffYUV RGB.
3. Import it in Premiere or After Effects.

Does it safe to convert in this way? Can Avisynth do some help here?

scharfis_brain
20th August 2006, 00:44
Load the file using the Cedocida CoDec. It has an option to put out YUY2 without major jaggyness.

However, my script function reinterpolate420() does a much better job interpolating 420 chroma o 422 using DcDi like interpolation than the plugin reinterpolate420().

EDIT: corrected several typos.

henryho_hk
23rd August 2006, 01:02
is DcDi a trademark actually?

scharfis_brain
23rd August 2006, 14:48
I dunno. why are you asking?

henryho_hk
23rd August 2006, 16:14
I found http://www.yamaha.ca/av/technology/DCDi.jsp in google and there is a "TM".

scharfis_brain
23rd August 2006, 16:55
I still don't know why you are asking.

Why does it matter whether DCDi is a trademark or not in relation to this thread?

henryho_hk
23rd August 2006, 17:06
I thought you said "DcDi interpolation".... Just discovered that you actually said "DcDi like interpolation".

scharfis_brain
23rd August 2006, 17:09
actually I found (and corrected) several typos.

one of them said "DCDi link interpolation" instead of "like"
so maybe this was the reason for this misunderstanding.

plane
21st September 2006, 20:31
Forgot to follow up my post....

I had some PAL DV clips contain a lot jaggies even through there are no bad upsampled?(used FFDShow libavcodec) They mainly happened at some high contrast(red/blue colour) diagional lines.

http://forum.doom9.org/showthread.php?t=83396
Actually, I am looking for Avisynth solution like this but I think it's just too slow to use with.

scharfis_brain
22nd September 2006, 19:51
just use the reinterpolate420() - script.

applieing antialisa is wrong here, cause it works on luma.

plane
23rd September 2006, 09:32
I tried you and Wilbert's script but didn't help at all. It was really strange. Finally, I playback them on a HDTV w/ DCDi and all jaggies gone. I don't have the clips anymore(actually, not my clips) so I'm sorry that I cannot offer them at here.