[SOLVED] multi-colour gradient, dreadful banding

[Draoidh]

So I really suggest that you upgrade your IM.

I'd love to but my sysadmin refuses to install anything that isn't in Debian. Debian sid (unstable) is up to IM 6.7.7.10-3. Looking at the changelog, we are only 5-6 weeks behind your version.

[fmw42]

So I really suggest that you upgrade your IM.

I'd love to but my sysadmin refuses to install anything that isn't in Debian. Debian sid (unstable) is up to IM 6.7.7.10-3. Looking at the changelog, we are only 5-6 weeks behind your version.

Are you saying that you are using IM 6.7.7.10 and you cannot use bicubic or get different results from what I posted? Do I misunderstand?

[Draoidh]

The latest greatest IM version I can get from Debian unstable is 6.7.7.10.

However, I tried 6.7.7.10 and I got totally different looking results with bicubic (see previous post).

Because of this, I went back to 6.7.7.2, which gives me banding with bicubic; but with bilinear I get a gradient that looks very similar to yours.

[fmw42]

I do not know what is/was happening with -interpolate bicubic. Anthony would have to comment.

[Draoidh]

Installed 6.7.9-8. Yeah - my gradients are working!!!

[anthony]

If you like to remove the black banding between primary colors, do the gradient in either LAB or LUV colorspaces.
This preserves the intensity when generating gradients.

[snibgo]

A new member posted, suggesting that "-spread 50" will reduce banding effects. This is true.

The rest of the post appears to be spam, including links to a website that advertises his products that are only vaguely about image processing.

I've removed the post, but I'm in a generous mood so haven't also banned him. But if he posts again, advertising his products, I will.