tags vs albums

[Jakub Steiner <jimmac ximian com>]

Hi Folks,

*food for thought*

I want to put the concept of tags, as we have them now in F-Spot, in
question and propose a more natural interface concept. The suggestion
comes from thinking about various tasks we came up for F-Spot [1],
taking export functionality in particular consideration [2].

Tags
====

As it stands, the user has a flat library of photos. Each photo can have
a set of tags assigned to it, such as what place the image was taken,
what event that was, who/what appears on the image. 

Query Logic
-----------
Tags enable the user to limit the view to images containing a specific
tag. The user can also select multiple tags at once. Contrary to my
point of view, this doesn't limit the query further, but enhances the
view by adding images containing tags using the OR operand. How many
times have you queried the library for "Photos from Boston or Tuomas"?
"Images of Dogs or Favourite Images?".

With the current interface, it is not possible to query for Event AND
Person so that one could get images of a person appearing while at an
Event.

Human Language
--------------
There is no clear metaphoric link to tags. In the physical world, we
structure our photos in albums or piles. It is not physically possible
to have one image appear in multiple albums.

Reuse
-----
With the tag interface to the library is not possible to store a certain
query. One has to manually deselect the current "filter" and apply a new
one.

Metadata
--------
We do want to have additional metadata associated with an image. It is
confusing to use this concept for some, and another for the rest (name,
caption...)

Export Implementation
---------------------
While it is theoretically possible to come up with a dynamic web system
for exporting photos on the web, retaining the same concepts as applied
on F-Spot alone with tags, it relies heavily on server side scripting
and doesn't sound trivial to do. Generating static HTML pages with the
tag interface is hardly doable with way too many permutations to deal
with.

Proposal - Albums
=================
I propose we use a concept of Albums and Virtual Albums (similar to
vFolders in Evolution) instead of tags.


Human Language
--------------
Album is a real world object that easy to understand. The term Virtual
Album clearly exhibits the difference from the physical Album.

Reuse & Consistency
-------------------
The concept of stored queries isn't new. We have them in Evolution and
hopefully thanks to beagle it will appear in the file-manager, file
dialogs and elsewhere on the desktop.

Metadata
--------
Image attributes (including the stuff that's done with tags now) is
defined at one place in the UI.

Export Implementation
---------------------
Mostly every web image gallery is structured in albums. Even stored
queries (Virtual Albums) could be generated as static HTML. 


Further Mindbender:
===================
      * Should we include Time in the queries? Or have time as a
        separate concept to further limit whatever you have selected in
        albums? That could give new options to the timeline scale - You
        select an album and the the time scale changes accordingly
        giving you options to further limit the selection by time.

cheers

[1] http://primates.ximian.com/~glesage/wiki/doku.php?id=f-spot:use_cases
[2] http://primates.ximian.com/~glesage/wiki/doku.php?id=f-spot:web_export