[SOLVED] multi-colour gradient, dreadful banding

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Draoidh
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Re: multi-colour gradient, dreadful banding

Post by Draoidh »

fmw42 wrote: 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. :(
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fmw42
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Re: multi-colour gradient, dreadful banding

Post by fmw42 »

Draoidh wrote:
fmw42 wrote: 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?
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Draoidh
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Re: multi-colour gradient, dreadful banding

Post by 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.
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fmw42
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Re: multi-colour gradient, dreadful banding

Post by fmw42 »

I do not know what is/was happening with -interpolate bicubic. Anthony would have to comment.
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Draoidh
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Re: [SOLVED] multi-colour gradient, dreadful banding

Post by Draoidh »

Installed 6.7.9-8. Yeah - my gradients are working!!!
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anthony
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Re: [SOLVED] multi-colour gradient, dreadful banding

Post by 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.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
snibgo
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Re: [SOLVED] multi-colour gradient, dreadful banding

Post by 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.
snibgo's IM pages: im.snibgo.com
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