Flat areas not smooth: What is this phenomenon called and how to get rid of it?

[moviefan]

If I watch a video of mine frame by frame, pixels in flat areas change their colours very slightly although there is no reason for them to do so. Thus the video loses compressibility and also looks very disturbing. What is this problem called and how can I solve it?
I hope you understand what I mean - it's a little difficult to explain...

Regards

[Zarxrax]

This can be calmed by a temporal smoothing filter, or a 3d spatial/temporal smoothing filter.

Some you might want to try are Temporal Soften, Temporal Cleaner, FluxSmooth, Deen. There are plenty others out there too.

[foxyshadis]

Most of the time it also doesn't really hurt compression - it gets eaten by the encoder, instead, and arguably looks even worse when that happens. Temporal smoothers can only somewhat fix it, but an ffdshow filter called "deband" can almost entirely hide it. It's also available for avisynth (called grad2fun), but again, fine dithering tends to get eaten.

[bananacreamandpeca]

But the problem is you don't want these artifacts in the encode whatsoever.
Or at least at a real minimum.

I'm encoding heman now (wich doesnt work, megui keeps aborting jobs halfway, don't know why)
But in the small bits of coded video I also see these rtifacts.
And the ARE disturbing to me. I don't want a deband-filter to
do the smoothing upon playback.
I want it to be 'just right' right in the source.

BTW. doesnt anybody answer my Questions?
Did the Moderator put me on a ghost-flag invisible for others to see?
Or am I speaking Arab or Chinese? My english isnt that bad I hope?

BTW. When I look at encodes by others, they always look good without any help-filter upon playback.
So it IS possible. But how?

Do I have to Smoothen the hell out of the source during post-processing with AVS?
In anime still backgrounds have these artifacts, why?
Do I need to deshake the source? Would that help?

[Mug Funky]

in my experience a lot of the time these artefacts are only visible on the computer screen and not on a television (or even when viewed through overlay mixer). i suspect it's the RGB conversion playing silly buggers - rounding causing blocks to be more visible.

as far as defining it - CCE's manual refers to it as block noise, but it uses the term quite a lot in different areas too.

encoders may eat dither, but if DC precision is high enough the dither will probably not go to waste (rather like dither in CD audio - dynamic range goes up, and even after encoding to mp3 the dynamic range is still high, even though the dither's been shaved off. you just need to decode it to higher precision).

kill it with a very faint temporalsoften. like thresholds at 1...

[Didée]

I've never used such a one, but isn't that what "pixel lock" filters are made for? (If a pixel changes only very slightly during a given frame interval, lock the pixel to one fixed value, until there is a 'significant' change again.)


OT:

Has anyone heard of bananacreamandpeca? He hasn't been around for some weeks now ... :D :D

/OT /joke

[HeadBangeR77]

Has anyone heard of bananacreamandpeca? He hasn't been around for some weeks now ... :D :D

/OT /joke
Excuse me, and my worm-tounge, is that a kind of a new drink or sth like that? I'm cruel, I know (I'm helpless :D). A decent OT might be really useful sometimes, nicht wahr?

(erase the above, wipe that, stick to the rules :D)