Re: image scaling

[Mathias Dahl]

>  Looking at the Elisp manual's "38.16.2 Image Descriptors", it seems that
>  we do not support image scaling.
>
>  I'd like to add such a feature to image-mode.el, but am wondering how we
>  should go about doing it.  Would there be some advantage to provide it
>  at the C level (e.g. if some of the image libs we use already provide
>  the necessary functionality) or should we just bite the bullet and call
>  some external tool like "convert -scale ..." (with the disadvantage that
>  flushing the image cache will not automatically cause the image to be
>  re-scaled).

It would be really good to have such a feature as I think it would
make browsing images in image-dired's thumbnail buffer (display some
large images there and use SPC and DEL to go back and forth to see
what I mean) much quicker. At least I guess it would be quicker to do
this natively inside Emacs than using convert to scale the image as we
do now. I assume the image libraries that Emacs use support scaling in
some way. When on the subject of images, it would be really neat if we
had built-in EXIF (et al) support as well, although I understand if
people do not think it fits well in Emacs.