bug#51381: HEIF image format support

[Lars Ingebrigtsen]

Stefan Kangas <stefan@marxist.se> writes:

>> Yes, imagemagick supports it, so (via image-convert and the external
>> commands) Emacs can display heic on Debian, for instance.
>
> Just to point out that we prefer GraphicsMagick to ImageMagick if it is
> installed.  Which is a good thing: it has better performance, security
> track record, and fewer dependencies.

Yes, GraphicsMagick is better all over.  But as usual, ImageMagick is
first out with support for the new shiny thing -- GraphicsMagick (in
Debian/bookworm, at least) does not support .heic, but ImageMagick does.

Stefan Kangas <stefan@marxist.se> writes:

> 1. emacs -Q --eval '(setq image-use-external-converter t)' /tmp/C001.heic
>
> But I get the error message "Unknown image type", and nothing else.

It probably autodetects GraphicsMagick?  The logic doesn't look for
support per image format, but just uses one of the three.

Try setting `image-converter' to `imagemagick' and restart Emacs.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no