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Pandora is a web-oriented application of JPEG 2000. It uses web pages
as a novel example of XML metadata. A multi-image, multi-page website can
be stored within a single JPEG 2000 file, and viewed using an ordinary
web-browser.
Look at these slides or this paper, which were presented at
EVA 2001 Scotland, to find out more about how
Pandora works. An earlier version of the slides is itself a Pandora file.
Two crucial features of Pandora are its ability to address objects within
the file via URLs, and its transcoding of image and markup data.
- To examine the URL structure, look at the "Location" or "Address" box in your
web browser as you navigate through the examples below.
- Image transcoding to JPEG permits compatibility with existing browsers. Other
image transcoding options enable Pandora to take advantage of new features that are unique to JPEG 2000.
- Transcoding of the markup turns XML into HTML. Tags can be rewritten
during this process, enabling image transcoding options to apply to entire pages.
Here you can see the following Pandora files:
- The Seven Sisters, transcoded to JPEG, or
delivered direct as JPEG 2000 for suitably
enabled browsers. (Under Windows you could install the
Elysium plug-in
to see the image in the latter example.) This illustrates
Pandora's ability to provide an upgrade path: from the same file it is possible to
obtain JPEG images for existing browsers, or JPEG 2000 images for enhanced
or future browsers.
- The Seven Sisters at various sizes and
quality rates. (Click on the links above the picture.) These are all generated
from a single JPEG 2000 image in the file.
- An example photo album of Florence. Again, for each
photo, the different sizes are all generated from a single image, using
JPEG 2000's "scalability by resolution".
- A demonstration of Regions of Interest technology.
One region of the Gold Hill image has been encoded in such a way that it is
downloaded before the rest. You can see this by clicking on the links to the
same picture at different quality rates. This example also demonstrates the
JJ2000 Java applet as well as the
server-side transcoding and direct delivery shown before.
You can also visit the old Pandora home page, which
links to some prototype examples of more technical interest.
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