bug#68006: 30.0.50; Image-mode speed

[Eli Zaretskii]

> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Cc: 68006@debbugs.gnu.org
> Date: Wed, 27 Dec 2023 13:13:13 +0100
> 
> I was comtemplating the idea of using 'image-dired-contents-sha1' to
> ensure that the image contents has not changed on disk.  But then I
> asked myself if a function "give me a unique id of this file based on
> its content" does not already exist in Emacs.  I could not found one but
> maybe we could create one (eg. file-unique-identifier)?
> 
> Or do you prefer to keep this into the image library?  In which case,
> i'll move this function to "image.el" or "image-mode.el".

I think for now it should be kept in the image library, yes.  I don't
quite see why it would be needed for other files (if it was, we would
have had it already by now).

Thanks.