Proposed draft for the thumbnail D-Bus specification

David Faure dfaure at
Wed Sep 10 02:16:44 PDT 2008

On Wednesday 10 September 2008, Philip Van Hoof wrote:
> On Wed, 2008-09-10 at 01:27 +0200, David Faure wrote:
> I think instead of org.freedesktop.thumbnailer you want a pluggable
> org.freedesktop.imageresizer namespace.

This is not about resizing only! Again, the input data could be any of kind of file,
not just images. This is about a "make a thumbnail of this file at width x height" service,
let's not play on words.

> Thumbnailing is not generic resizing of images (without even storing
> it), if you just resize an image and don't store it .. it's called
> resizing. period.

This is a very limited view - the input for a thumbnailer/previewer isn't only images.
There is a need (and an implementation in kde) for thumbnailing/previewing
images, but also plain text, HTML, OpenDocument files, SVG, and more.
The service that provides a PNG out of those is not to be called resizer, but thumbnailer.

> If you indeed set up that specification and if you make a desktop
> neutral prototype and it indeed becomes part of freedesktop, I'd be
> happy to let this org.freedesktop.thumbnailer.Generic use the
> specialized resizers in org.freedesktop.imageresizer instead of its own
> specialized thumbnailers in org.freedesktop.thumbnailer implementing
> org.freedesktop.thumbnailer.Thumbnailer.

Yeah sure, reply with "you do the work" to make sure you win because I don't
have time for this. There is no need for a separate imageresizer service,
all we need is a bit more flexibility in the thumbnailer service.

> The org.freedesktop.thumbnailer.Generic getting a SHM from the elected
> specialized resizer, and then the thumbnailer storing the resized pixbuf
> as specified by the thumbnail-spec, and signaling the `Ready` signal.

Yes. With s/resizer/thumbnailer/ ;)

> Regretfully I didn't start with an existing org.freedesktop.imageresizer
> being available. 

No, but you're specifying the thumbnailer service which will have the
data-to-image code, and that's exactly what this theoretical imageresizer
would be anyway. Don't do a "SEP", it's not true.

> My POV is that current freedesktop's DBus APIs don't go that far yet,
> perhaps with the exception of richer frameworks like Telepathy, and
> although the idea fits my view of taking over the world, I fear this
> wont happen in time. Maybe in a few years we will have this, indeed.
> But if nobody is hungry for specifying a o.f.imageresizer, let's stay
> with our both feet on the ground and start modest with just a namespace
> like o.f.thumbnailer.

In this case "modest" == useless. Sorry.

You're making this a specification in order for this to be shared
among desktop environments, no? Why then
1) ignore actual working implementations of this?
2) ignore comments from people who know those implementations?

I can see yet another gnome-only freedesktop spec coming up, if it is made
less useful than kio_thumbnail :(

David Faure, faure at, sponsored by Trolltech to work on KDE,
Konqueror (, and KOffice (

More information about the xdg mailing list