What is this problem called (and how to fix it)?

[Chengbin]

http://i29.tinypic.com/2qdxslf.png

What are these tiny blocks called? Is there a way to fix them?

[Guest]

They're called pixels. It is not a problem. Every image is made up of pixels.

[thewebchat]

That's a light banding. You can fix it by adding some noise to the image, perhaps with GradFun2DB (or GradFunkMirror).

http://img168.imageshack.us/img168/879/banding.png

[thetoof]

2 options : flatten the image by denoising to hope that averaging won't screw up the details or introduce more noticeable banding elsewere
OR
add noise (deband) with gradfun2dbmod or anything you prefer

1st takes less bits to encode but can be visually displeasing
2nd will be harder to compress

There's always c) do nothing as it seems hardly noticeable as thewebchat said... though it's hard to judge with a cropped snapshot

[Chengbin]

Thanks. I'm gonna try gradfun2dB