Picture revolution around the corner

By Julie Maske
Illustration: Gorm Kallestad

Over 180 countries have been working together for many years to reach agreement on a common system for the digital storage of images. Finally late 1999, at an ISO standardization meeting in Maui, they achieved their goal. The new image-storage format is called JPEG2000.

There are enormous advantages associated with this new format, according to Associate Professor Andrew Perkis at the Department of Telecommunications, NTNU. He has led an EU-funded project which has coordinated the European contribution in the work defining this common system.

There are many different ways of storing pictures today. The big players on the market such as Siemens, AGFA, Kodak and Adobe all produce their own format for the digital storage of images. This makes it hard, and sometimes impossible, for users to exchange digital-image files. With a single system such exchanges will become much easier.

It will, furthermore, be much quicker to use the Internet, as JPEG2000 files are much 'easier' to transmit and receive. Pictures stored in JPEG2000 format take up much less storage space. For example, an ordinary X-ray picture requires about eight MB in storage space using current systems. In JPEG2000 format the same amount of space will probably allow storage of 50 X-rays.

Another advantage for hospitals, among others, is the possibility of storing parts of a picture in high resolution, while the rest of the picture can be stored in low resolution. JPEG2000 files can also be protected against image-manipulation: they break up if an attempt is made to change them. As a result it will be possible to protect the rights of the originators of digital pictures.

'Cordless' possibilities

The Department of Telecommunications at NTNU has contributed to the development of the technological part of JPEG2000. In addition, Perkis is also working to combine image-storage with communication by cellular phone, such that pictures can successfully be transmitted over for instance, the GSM net.

Fast, cordless communication of digital pictures over the GSM net requires noise- and hiss-free transmission, otherwise the pictures will simply be destroyed. This is different from the transmission of sounds over the GSM net. If the line crackles a bit while we are talking on a cellular phone our ears can generally make sense of what is being said. Pictures, by contrast, must be transmitted without any interference. Once NTNU has developed a 'cordless' system that can manage this, yet one more piece in the digital picture-world puzzle will have been put in place.

Contact at NTNU: Andrew Perkis
Tel.: +47 73 59 23 83
E-mail: Andrew@tele.ntnu.no