Add support for JPEG-XL (file extension: jxl)

[StableLlama]

Add the possibility to use images in the JPEG XL file format.

This PS doesn't change any other setting, especially it doesn't touch any places with hard coded file formats.

[bghira]

why does this add the import all over the place?

[StableLlama]

It does it everywhere PIL is included and then it is used to load or save an image to make sure it has this plugin.

[StableLlama]

I've got git problems solving the poetry.lock conflict. Till it's solved it's just a draft.

[bghira]

i think it's only necessary to do that in the image load function, since that's the one spot this is handled everywhere. but the default file loader is CV2, not PIL.

[StableLlama]

poetry.lock is now fixed. Sorry for the commit history bloat, I'm not that familiar with git so that I could have avoided it. But looking on the file changes them self will the correct truth anyway.

About the image loading I searched for all files that were including Image from PIL and also were using either open() or save(). In my test ST correctly took the images from the multidatabackend.json and placed them in the VAE cache directory.

When I missed it somewhere, e.g. due to CV2, I'm happy to look again. But I'd need a hint where I have to look :)

[StableLlama]

Ok, there were only two places that are using CV2 instead of PIL to load an image. I've added a PIL fallback when CV2 doesn't understand a codec

[bghira]

where you're adding the import, these scripts aren't always needing JPEG-XL. in general, i'd like to avoid having it as a baseline requirement because it sort of a rare format. we can wrap the import in a try catch and leave a note about JPEG-XL being unavailable.

[StableLlama]

JPEG XL is not common right now, but it has wide momentum and is made available in many different places - and it's a great format for our usecase here. But I don't want to discuss formats, as that tends to be pointless 🙂

Now I've made it completely optional. Right now it's by default not included, but we could easily change it to be included by default with the possibility to exclude it.

The crop.py also isn't using the CV2 to PIL fallback anymore.