A Standard for Thumbnailers

[Benedikt Meurer]

Stanislav Brabec wrote:
> - Image files in public directories are thumbnailed many times:
>   once for each accessing user.

Sharing thumbnails might be a security problem.

> - Thumbnails on removable media are thumbnailed many times: once for
>   each machine, where medium is accessed

IIRC the standard already covers this, tho it's not implemented in Xfce
and GNOME.

> - Thumbnail files are often larger than images itself, especially for
>   jpeg images below 20kB in size.

The software can detect this and load the JPEG directly.

> - There is a very small chance to detect deleted images and delete
>   corresponding thumbnail.

The file manager should clean up the thumbnails when deleting files.

> Use unique inode_number/volume_id instead of file_path.

This will not work with certain FUSE file systems, that generate unique
inodes on-demand, because it's likely that the inodes will be different
each time the file system is mounted.

> Haw widely used desktop-neutral thumbnailing library understanding many
> embedded thumbnails and providing thumbnailing for images without
> embedded thumbnail.

I think external thumbnailer as used by Thunar/Nautilus are better,
because it's more flexible and avoids loading various libraries required
to generate thumbnails for different formats into the processes.

Using .desktop files to register thumbnailers instead of GConf should be
fine for desktop-neutral usage.

> Allow jpeg thumbnails.

Aside from maybe a few bytes saved per thumbnail, why would you want to
do this?

> Thumbnails can use file system extended attributes.

Not every file system supports that. What would be stored in the
extended attributes anyway?

Benedikt