Debanding advice

[Akai-Shuichi]

Here is a sample https://www.sendspace.com/file/1bdci9

I've run just straight Gradfun3() and it reduces it a decent bit, but wondering if there is anything else that can kill it even more.

[Shaylen]

Re-using the filter is not illegal.

For e.g. Sharpening the image with the Sharpen() filter with 2.0 as param, trick is that the highest value is 1.0 so..

V=source..

V=Sharpen(V, 1.0)

V=Sharpen(V, 1.0)

V

The same goes with any [Video/Audio] filter.

[jagabo]

To keep banding from coming back you need to encode with sufficient bitrate and/or with a 10 bit codec.

[Selur]

I prefer f3kdb (https://f3kdb.readthedocs.org/en/latest/) over gradfun3 + jagabo is right debanding in Avisynth is one step to keep the dithering a higher bitrate or 10bit encoding is needed.
Also, most Avisynth filters have parameters which allow to lower or increase the effect of the filter.

[killerteengohan]

Here is a sample https://www.sendspace.com/file/1bdci9

I've run just straight Gradfun3() and it reduces it a decent bit, but wondering if there is anything else that can kill it even more.

Last I recall, gradfun2dbmod was a pretty good dithering filter for removing banding.

http://avisynth.nl/index.php/GradFun2DBmod