In RDFWeb, we are experimenting with a
distributed database of descriptions of people, images, movies, sound clips
etc. The initial demos have a way of saying that a person has a
foaf:depiction that is some media resource such as a JPEG image.
We then began experimenting withe notion of "co-depiction", a made up phrase
for circumstances where two people are both depicted in the same
representation (photos etc). This document reports on some initial
experiments with SVG, using SVG alongside more traditional photos so we can
be clearer about the regions within an image that depict different things. In
future work, we hope to extend this exploration to the use of SMIL with video
content.
Example
The example
photo includes both Charles and DanBri. We wanted to represent this in
SVG. Using W3C's Amaya browser, we can use graphical tools to create and edit
an SVG file that provides the basis for this.
How to create an SVG overlay for an existing online JPEG, PNG etc., using
Amaya SVG's SVG tool. Charles showed me how to do this, so I thought I'd
write it down for others to try.
File > New > New SVG Document (ctrl-x, ctrl-g)
Type or paste full URI for where the new SVG document will live (eg.
http://www.w3.org/2001/08/rdfweb/co-2.svg)
Select your new SVG document, and then select the 'Insert Image'
(picture) icon from the menu
bar
Paste the URI of your original image (photo etc) into the 'Insert
Image' field in the dialog box, with a short description for 'Alt text'
(bug workaround for Amaya 5.1 and earlier:
Save your document (File Save / ctrl-x, ctrl-s / button / ...),
entering username/password if prompted
Reload the SVG image (remember to make sure the Web server settings
give you access to the file);
The SVG should now display properly, including any referenced
external image resources)
Select the image, and, then activate the Amaya graphical toolbar by
selecting the '' icon
from the menu bar
Choose one of the graphical tools (screenshot)
the smooth or jaggy curved shape, and click on a start point in the
image
Use the mouse to create new points in your outline path (eg. tracing a
shape in a photo); esc, right-click or switch windows to finish shape
Select id from tthe attributes menu, and give the outline
a unique identifier (must start with a letter, and not have spaces in it,
and be letters/numbers/dash/underscore). This is so you can make RDF
statements about this particular piece - it has a URI now.
Save the SVG document to record these changes in the Web
Use Amaya's Views > Show Structure facility to see the how SVG is
written in the XML infoset tree (Example
screenshot)
Things to Explore
These are on the some-day pile. If you're a student or if you run a class
with students who might be interested in a project based on this stuff, send me a note.
How does this relate to the RDF Annotations tool in Amaya? (Annotea)
How can we use the SVG structures with RDF to describe in RDF which
things an image represents? ("this bit of the image represents the person
whose home page is..."; this bit of the image represents a thing of
rdf:type http://xmlns.com/wordnet/1.6/Beer ... etc)
Improving the image cataloguing process, so people will do this for
their own image archives: We could use Amaya to link a part of an image
to the relevant codepiction page, and then run the resulting piece
through a transformation. I don't know the Amaya Transformation language
enough to do this, so we would have to make it an external XSLT for now,
but I will investigate this more. (this would also help solve some of the
previous things)
Find or write a howto on making an HTTP-PUT friendly server for use
with Amaya
Amaya wishlist ideas: drag-and-drop editing of paths, polygon shapes
etc. once created would be nice; as would a UI widget for adding
<metadata> elements that RDF-describe parts of the image - Annotea sort of provides some
of this.
icon from the menu
bar
button / ...),
entering username/password if prompted
' icon
from the menu bar
