HEIC HEIF support

[skjnldsv]

If possible.
Pulled from specs on nextcloud/server#12382

[rullzer]

since the viewer only shows preview this will work out of the box if you have a preview provider that can do it 😉

[skjnldsv]

@rullzer what do you mean?
We still need a library to display those files, right?

[rullzer]

No we do not. If the preview system generates a preview it will be severed as JPG by the preview system. :)

[skjnldsv]

@rullzer we do not do previews here, we do full view of the file.
If the file is a HEIC and contains multiple files, supporting it in viewer shall display all the content without alteration. :)
That's part of the spec!

[rullzer]

Why do we not use the previews? gallery also uses the previews. it is a bit silly to start loading 20mb jpeg files.

[juliusknorr]

I would also prefer to go for previews by default. We can still integrate some HEIC HEIF javascript viewer later in order to support thinks like burst shots or videos integrated.

[skjnldsv]

@rullzer Well, that is a good discussion to have!
@jancborchardt specifically told me to not use previews since this was supposed to be a file viewer! 🤷‍♀️

Can we move this to another dedicated issue? :)

[jancborchardt]

specifically told me to not use previews since this was supposed to be a file viewer!

We can always start by displaying the preview as a first implementation or step? The full picture can always be loaded in the background, if necessary. (This is also what we do on Android, and what iOS photos does.)

[ariselseng]

I opened another issue here, without check this thread first!
#28

Basically any file that has true in the propfind DAV request should use previews. Then we can make exceptions later for animating HEIC or something like that. Preferably with a srcset that would use the best image for the screen.