Artifact?!

[FreierGeist.]

Hi.
I hope that some one could enlighten me about this weird artifact that came after an 2 pass XviD (Koepis 03052003 build)...
the avi clip its here: http://hypokeimenon.hypermart.net/sample.avi
And... the artifact (at the extreme right of the screen) appears in the entire video (not as a constant, as you can see in the sample).
The .avs i used is:
loadplugin("C:\Program Files\Gordian Knot\mpeg2dec3.dll")
loadplugin("C:\Program Files\Gordian Knot\decomb.dll")
loadplugin("C:\Program Files\Gordian Knot\msharpen.dll")
mpeg2source("D:\das.d2v")
crop(16,68,678,344)
ChangeFPS(30)
Telecide(threshold=10,dthreshold=6)
Decimate(6)
LanczosResize(544,304)
Tweak(bright=20,sat=1.3)
MSharpen(threshold=10,strength=80)

and the XviD settings are:
6-ultra high
h.263
XviD
VHQ=1
Max/Min I-Frame Interval: 260/10
Lumi Masking
Chroma Motion
B-Frames: 2/150/100/255
DX50 B-VOP compatibility
Quantizer: 2/6/2/16
Playback Proportional


Thank you!

[sysKin]

It can't be XviD bug: it appears both on B-frames as well as in P-frames... I'd say it's avisynth doing something weird, I think...

And let me give you a tip on compression: don't ever leave such dark line on the right (or left, or bottom, or top...) of the picture. Such line cannot be motion-compensated correctly and takes a lot of your bitrate. It's better to cut too much than too little.

Radek

[manono]

Hi FreierGeist-

Yep, crop away the black. And there's a good chance that stuff along the right side is on the DVD like that-check the vobs, and maybe crop it away also. I think I'd probably use AssumeFPS(30), rather than ChangeFPS(30), and then adjust the audio in BeSweet. ChangeFPS adds a new frame every once in awhile.

I don't know which version of Decomb you're using. Older ones require the width to be divisible by 4-another reason to adjust the crop. Either that or put the Telecide-Decimate before the crop. From the Decomb help file:
Telecide requires that the input width be a multiple of 4.

[duartix]

I had a similar problem on "Dead Cand Dance - Toward the Within" and I got to the conclusion that the Avisynth Filter I was using wasn't working too well on the borders, so my advice to you at this moment is:

1 - Try to isolate the filter causing this.
2 - Even though it seems counterproductive, if all else fails then Filter first, Crop afterwards. Sometimes the filter doens't work too well when it doesn't have the surrounding black pixels to work on.
3 - Or if you think the trouble is worth it:
Crop most of it (leaving some black pixels for the filter to work), Filter, Then crop the excess. Should be faster than 2.

[crusty]

Don't crop before deinterlacing or ivtc. Decomb needs the whole uncropped picture to do it's work. You might get weird problems if you do.

[FreierGeist.]

really strange...
i've tried to isolate filters to find if the problem was caused by one of them, but it wasnt
then, i created a new .d2v and, analysing the same .avs (with the new .d2v) in the VDub, before encoding, the artifact disappeared
so... i'm finishing a new test and i'll post the results...
thanks!

@manono: even beeing a non secure way of getting reasonable results, Decomb processed the Change"d"FPS well.. the result's good
and (of course its because of a dumb-use of BeSweet) i was having difficults making the proper changes to the audio :D

@crusty: that sounds reasonable... although i can't assure that's whats causing the problem
anyway... the test will finish soon

[FreierGeist.]

:confused:
i can't figure out whats tha problem
i isolated, again, all the filters... changed the resize filter... put crop after ivtc...
and the artifact's still there... :confused:

[FreierGeist.]

@sysKin and manono: thanks for the tip, but i didn't left any border :(

[FreierGeist.]

and i tested almost all the xvid config..
VHQ, Chroma Motion, Luma Masking, etc

[ARDA]

I imagine here is your problem
crop(16,68,678,344)
678 is not multiple of 4

Arda

[FreierGeist.]

Arda: BINGO!!!! :D:D
You're absolutely right!!!
ps.: are you married? :p

THANK YOU!!!