Banding after conversion from HDTV

[OutSiderSP]

I have been trying to convert a HDTV captured documentary to DVD so I can watch on my TV. The source is DivX HDTV 1280x720p. I use a simple script to frameserve to CCE 2.67:

AVISource("D:\xxxx.avi")
Undot()
BlockBuster(method="noise",detail_min=1,detail_max=4,variance=0.5,seed=10)
Limiter()
LimitedSharpenFaster(dest_x=656,dest_y=448,smode=3)
AddBorders(24,16,24,16)
ConvertToYUY2()

unfortunately, there are lots of takes done undersea and, therefore, big areas coloured from deep navy blue to bright sky blue. I can see no banding in the original source using MPC, but after converting to mpeg2 I get awful banding. i used 3 passes, min=1000, max=9000, avg=4500 in CCE.

Is there a way out of this or should I live with this nasty banding ? I tried Convolution3d, FFT3filter, and some others I cannot remember. Can anyone give me a hand in this conversion? Or just tell me I have to live with this problem, it'd be ok.

Thanks a lot in advance.

[Boulder]

Remove the ConverttoYUY2() line and try encoding with HC. It might be that the YV12->YUY2->YV12 conversion is causing the issue.

[OutSiderSP]

Thanks a lot for your reply, Boulder.
I did some tests and found out that :

1-The source already has some smooth banding. Probably the MPEG converson only amplified it.
2-HC produces less banding, but it is still present.
3-CCE with One Pass VBR produces less banding than 3 passes VBR, though it is still bad.
4-TMPGEnc also produces banding, though less visible in the dark end of the picture.
5-CCE with CBR at 9000 kbps produces the same banding.
6-Extracting the worst banding part with VDUB without processing also increases the banding effect. I thought that VDub only copied part of the film without decoding it. Maybe I have a problem in the DIVX decoder. As MPC loads DIVX automatically, I will try to either play with its parameters or try DirectShow.
7-I will resignate and accept the banding. But, i will try to burn a DVD-RW with a small sample and let my eyes check it.

Has anyone tried DIVX 6.2.2 ? I can try to install it and see if the decoder is better.

If I find anything else, I will post the results here.

Anyway, thanks a lot.

[Boulder]

Did you use Direct stream copy to extract the troublesome part?

Could you post a screenshot of the banding (enhance brightness if necessary to see it)?

I would try adding noise to the source video, it might help a bit.

[OutSiderSP]

Boulder,
I did some other tests and all failed, like inserting a lot of noise and all. Don't care about this problem, it's just curiosity, ok ? you've been too nice to try to help.
Anyway, I will install Divx6.2.2 and see if it helps. I do not have a place to put my files, but I will prepare it (the worst banding part) and put in my ftp server and you will be able to get them.

But, I insist it's not important, do not waste your time on that, ok?

Thanks a lot !

[OutSiderSP]

Boulder,
I'd like to thank you a lot for your help. A lot of forgotten filters and methods came back to my mind after our talk. I tried your suggestions and they worked fine. I can hardly see any banding on TV if I connect it through YCBCR. It is just plain watchable !

Thanks a lot. And i will keep your noise function, for sure !