Forecasts
predictions of the cutting edge
JPEG2000
Trudy Levy
Image Integration
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The Joint Photographic Expert Group has had their hands full. More then 10 years ago, as a working group of the ISO, they developed what was to become the most popular photographic image file format the JPEG or JPG as its denoted in the Windows environment. Unfortunately while it helped to contribute to the overwhelming popularity of photos on the web, it is based on old technology and has been vastly over worked. For the past three years JPEG with JBIG ( another joint committee) has been working to improve on the JPEG. DIG ( Digital Imaging Group), an Industry association has also involved itself in the process as their members will be the major one to implement and adopt the new format.
So far it has passed to Final draft and hopefully by the end of 2001 it will be accepted as an industry standard. With DIG involved, that should be relatively smooth.
As with much else in this time, the major imaging needs which the Experts have been attempting to fulfill, are a result of the Internet. The DIG2000 Initiative summarized that impact as being the Distributed Nature of a Network. It is no longer clear what device or what application is responsible for a file. Another major impact has been within the imaging field itself. More people can now easily create high resolution richly colored images. The JPEG can only communicate RGB. To meet these changes in out imaging needs, the consortium set the following goals for the new file format.
Be an Open Standard so that images can easily be interchanged between applications and devices
Improve compression to accommodate more image information.
Optimize flexibility and bandwidth utilization
Contain met a data or non image information about the file as part of the file.
The core of the JPEG2000 new specification is Wavelet Technology. Rather than creating discrete parts of information, Wavelets are mathematical equations (algorithm) which encode images in a continuous stream. This results in incredible compression. DIG maintains that you can get the information equivalent of the FlashPIX file in a 40% smaller file.
Streaming will also allow for progressive access of one file. The same file may be accessed as both a low, mid and high level resolution, depending how the viewer requests it ( or is permitted to request it). You will also be able to do the same thing with richness of color. They call it either progress by resolution or by quality. No multiple image files.
In addition the JPEG2000 format will allow for more then just the RGB information of the current format. You will be able to describe complete color spaces, CMYK for example, and include Color profiles, such ICC. Thus your image file can tell a printer or a web browser how to render its blue accurately.
And all this will be an Open Standard which all software can offer. With luck it will be adopted soon.
5/4/00
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