Licensing problem

[atitan]

Hi there,

pHash is released under GPL 3.0, which restricts programs using it should have same license as well.
I think phashion's current license is a mistake.

http://phash.org/licensing/

[eregon]

This seems a serious issue, @westonplatter could you reply to this?

[westonplatter]

@eregon I hear you. Overloaded at the moment. Licensing questions are not my forte, so any help is appreciated.

@mperham any input on this?

[mperham]

I have no input. IANAL and don't want to make any incorrect statements on this subject.

[westonplatter]

@atitan circling back on this. I'm also not a lawyer and therefore have no advice to give on the subject.

[eregon]

http://phash.org/licensing/ is very clear, there is no need for lawyer interpretation here, this gem must use GPL3:

pHash is open source software released under the GNU General Public License (GPL) version 3. This means that if you use pHash in your application, it must also be released under the GPLv3. If you wish to distribute a commercial application without including source code, you must obtain a commercial license.

Also https://github.com/aetilius/pHash/blob/master/COPYING
From GitHub's description of GPL3:

Permissions of this strong copyleft license are conditioned on making available complete source code of licensed works and modifications, which include larger works using a licensed work, under the same license. Copyright and license notices must be preserved. Contributors provide an express grant of patent rights.

There is the https://en.wikipedia.org/wiki/GPL_linking_exception but it doesn't seem used by pHash here.

So https://github.com/westonplatter/phashion/blob/master/LICENSE should be changed to the same as https://github.com/aetilius/pHash/blob/master/COPYING
And https://github.com/westonplatter/phashion/blob/master/phashion.gemspec should use s.license = "GPL-3.0".

This might require getting the permission of past contributors though, to relicense from MIT to GPL3.
To be on the safe side I would suggest to ask them, like it was done e.g. in ruby/strscan#25 (comment)

Not doing anything is almost certainly an infringement of pHash's license.