Images and GPL compatibility

[mundschenk-at]

I realize this is not your main concern for this package, but is there a chance to get in touch with the artists and ask them to relicense (or dual-license) the images as CC-BY-4.0 to allow for compatibility with GPL-licensed implementations? I wanted to integrate @nimiq's Robohash SVG into my WordPress plugin Avatar Privacy, but it looks like their SVG parts are derived from Zikri Kader's set1. (They might have relicensed them from Zikri, but going with proven provenance PNG icons seems safer.)

[e1ven]

I can totally understand why that'd be useful, but these were people I last talked to most of a decade ago.

Outside of what's in the code, I really doubt I even have any contact information anymore, and wouldn't want to bother them.

Is there something in the CC-BY 3.0 which is incompatible with the gpl?

I know they made changes to make the ShareAlike license more compatible, but doesn't the GPL require attribution anyway?

[mundschenk-at]

Attribution is not the problem I think, but apparently only the 4.0 versions of the CC licenses (other than CC0) are compatible with the GPL at all:

• CC-BY 4.0 with either GPLv2 or GPLv3,
• CC-BY-SA 4.0 only with GPLv3.

[mundschenk-at]

After some research, you might be in a position to release that artwork under CC-BY 4.0 yourself, @e1ven:

In the course of a 99designs contest, the copyright (and related usage rights) are transferred to the client when a winner is picked. To check if that procedure was the same back then (probably), you should be able to access the signed agreement from your 99designs account. (Of course, I don't know if you had similar agreements with the other sets or if they were different because it was done outside 99designs after the contest was ended.)

[e1ven]

That wouldn't solve the issue for the non-set1 artwork- As you surmised I worked with them outside of 99 designs.

But it looks like it would work for the default robots, which is all I think you need (via the SVG version)?

In that case, as the current copyright owner, I hereby additionally release the set1 artwork under CC-By 4.0.

You can use that or the version originally granted in the code.

Will that work for you?

[mundschenk-at]

I think it would, yes. It would probably be best if you could also add it to the README via a commit, to make it more permanent for reference, though.