support freeimage plugin instalaltion using pip install imageio[freeimage]

At the moment the freeimage plugin needs to be installed using either imageio_download_bin freeimage or imageio.plugins.freeimage.download(). This has to be run after the python environment has been set up with pip.

This is not ideal as one may want to be able to install the plugin when setting up the python environment with pip and not later at run time or in a post-installation script. One would also want the executable to be downloaded in the imageio module folder instead of being download in the user local folder. In contrast the plugin gdal can be installed pip install imageio[gdal] and thus is would be great to support pip install imageio[freeimage] as well.

[FirefoxMetzger]

Yes we can, but it looses the ability to auto-import. I.e., you’d have to do something like

import imageio.v3 as iio
import imageio_freeimage

This would make import imageio_freeimage register the plugin in imageio (assuming we add logic for this) and any code below would pick it up and choose it automatically again.

That is until I figure out how entry points for packages are supposed to work and we can begin to auto-discover/auto-configure plugins that live in external packages. This would be a generic interface so it wouldn’t be a derivative work and should be resistant to GPL.

[almarklein]

No idea if adding config entries for a library is enough to make it count as derivative work

Eek! Good point. I think it might. Do we still have an option for external code to register itself as a plugin? If not, I suppose imageio-freeimage would have to be a standalone lib?