The last two features essentially provide the same information. Both the root mean square error and the normalized mean square error are used to measure how effectively the image was compressed. These features measure the amount of pixel reconstruction error. Finally, there is a quit button that exits the MMI gracefully. 2.2 Image viewing A critical stage in evaluating lossy compression is viewing the image.
JET contains two ways of displaying an image.
The first method is via the Megascan feature. If a Megascan monitor is not available, then the user can display the images on a SUN workstation 8-bit color monitor under OpenWindows 3.0. We have developed a program, Imview , for this purpose. This program has evolved into a tool that is valuable in analyzing the digitized radiographs and in optimizing the JPEG compression algorithm for cervical radiographs. The Imview program not only displays images but includes certain functions basic to our study.