Compression technology that lets you store 200M of data on a 100M hard disk is commonplace nowadays, but until recently the same compression standard couldn’t be used to squeeze more data onto CD-ROMs. The problem? CD-ROM data is written in a single spiral track; it isn’t organised into the tracks and sector’s that compression software looks for.
Now, CD ROM-USA has released a software driver called CRI-X2 that fools software into seeing a CD-ROM as an ordinary hard disk. Incorporating Stac Electronics’ Stacker Anywhere compression technology, the driver lets CD-ROM developers double the amount of data they put on a CD-ROM disk.
One commercial licensee of CRI-X2 may help usher in the acceptance of 3-5in CD ROMs in notebooks. It plans to compress the contents of a 5in CD-ROM onto a 3 5in CD-ROM made for portables.
To compress a disk, the developer must send the data to CD ROM-USA, where it’s compressed using Stacker 31 with the same compression ratio you get on a regular hard disk. The compressed CD-ROM disk is sent back to the developer for duplication. The CRI-X2 driver works its magic by loading a small program into memory that acts as a virtual File Allocation Table (FAT) and lets the operating system see the CD-ROM as a hard disk. The Stacker Anywhere driver then does real-time decompression as the files are read from the CD-ROM to the PC.
According to the company, the CRI-X2 driver has no performance penalty when used with a 486 or faster processor, and in some cases it actually increases performance because data is being transferred in the same amount of time.
No disks that use the CRI-X2 driver have been released yet, but CD ROM-USA says the driver has been licensed by a number of CD-ROM developers who intend to reduce the number of disks in their data-base and documentation products.
