C-CUBE Microsystems Inc, San Jose, has, as reported last week (CI No 1,370), brought the day of affordable photorealistic animation a whole lot nearer with its single-chip photograph and video frame image compression processor, the CL550, which compresses by discarding data in the graphics image that covers frequencies not visible to the human eye. The chip promises to exploit some of the processing and storage demands of applications such as multimedia applications and colour desk-top publishing. One of the difficulties of transferring and manipulating high-resolution colour images or full motion video is the size of the data files required to store these images, notes Microbytes Daily. An 8 by 10 photograph requires approximately 25Mb and 30 frames of video, or approximately one second of time, requires 30Mb. The advent of data compression processors in computer, as well as in consumer electronic devices such a digital cameras and video recorders, will have major implications for graphics technology. The ability to cut these storage requirements by as much as a factor of 25 means faster transmission rates and much smaller memory, storage, and bus bandwidth requirements. Even with compression ratios of 10 to 1 for screen images and 25 to 1 for print, the difference in visual quality is hardly noticeable. In a demonstration for Microbytes Daily even larger compression ratios produced acceptable images though quality does reduce as the compression ratio is increased. The standard compression algorithm used is proposed by the Joint Photographic Experts Group and is supported by IBM, DEC and NEC. C-Cube also has a software version of the JPEG compression algorithm, the Compression Workshop, available on the Apple Macintosh II and retailing at $550. A 30 to 1 compression of a 30Mb image takes about one hour using the software algorithm on the 68030 processor for the Macintosh; it takes one second using the CL550. The CL550 will certainly have competition from other chip designers, particularly in Japan, but C-Cube marketing manager Mauro Bonomi believes his firm is over six months ahead of the competition.
