Q+A CENTER

Current technology trends in medical imaging are producing larger images, and more images with resolutions exceeding 4,000 by 4,000 pixels. In addition, there is an ever-increasing number of slices delivered by the latest medical imaging equipment. Network storage and transmission capabilities are under pressure.

JPEG 2000 image compression combined with a JPIP implementation (Part 9 of the JPEG 2000 specification) can address these challenges. JPEG 2000 offers better compression ratios for large images than standard JPEG compression in lossy mode, and also offers an efficient lossless mode. JPIP is used to optimize image transmission so that the user may view the image more quickly.

Using JPIP, a network of remote diag­nostic users can more quickly nav­igate through large image sets. Instead of waiting for trans­mission of a complete image containing millions of bytes, data from the source image comprising only a low resolution version of the image, perhaps 1/20th the size, can be requested and retrieved for initial viewing. Then, as each area is selected, only the relevant data is transmitted. This selective viewing on demand dra­matically improves the user perception of down­load speeds.

A typical JPIP implementation involves two main comp­onents: a server that stores the full image sets and delivers partial or full images as they are requested, and a client that requests those images and displays them.

The PICTools software development kit (SDK) by Pegasus Imaging empowers software engineers with the technology to design and build a complete JPEG 2000 / JPIP imple­mentation. The PICTools SDK provides multi-platform C/C++ libraries.

Paul Firth
Product Manager
Pegasus Imaging Corporation
www.pegasusimaging.com