Milpitas, California-based Dolch Computer Systems Inc has been busy making announcements, unveiling a standalone-cum-overhead projection panel, as well as a Digital Video Interactive option and a compression decompression algorithm for its PAC portable computer line. Firstly, Dolch has announced Prism – that stands for PRojection and Integrated Stand-alone Monitor – a 7 lbs colour thin film transistor panel that fits in the briefcase, and can serve as both an overhead projector and a stand-alone monitor. With a proprietary snap-on backlit cartridge, it is transformed from being an overhead projection panel into a stand-alone monitor. In either mode, it supports up to 185,000 of computer or commercial video signals, including VGA/EGA, Apple Macintosh, NTSC and PAL. When inserted, Dolch notes, the backlight cartridge does not change the dimensions of the Prism, which are 15 by 12.5 by 2. Dolch has also announced the addition of a DVI – Digital Video Interactive – option to its power portable multimedia product family. This provides hardware and operating system support to convert DVI signals into video drivers for thin film transistor flat panel and VGA monitors. Dolch is claiming that its bundled DVI option to the PAC product line is the first fully-portable package for the DVI multimedia user community, and is compatible with all industry standard DVI applications and development software packages. It enables the production of programs and presentations in the IBM Corp-Intel Corp DVI standard without being anchored to a conventional desktop personal computer. Fully configured, the Dolch DVI drives both an analogue VGA cathode ray tube display or it can drive both displays simultaneously, producing 256 colours on the screen. The DVI option consists of Dolch’s proprietary DVI/VGA conversion hardware and drivers, and the Intel ActionMedia delivery board which uses Intel’s 80750 chip set. The two-board set is fully bundled for DVI playback applications, and is compatible with third-party DVI capture boards, if the application calls for input, as well. Dolch’s proprietary DVI technology uses the Chips & Technologies Inc 82C457 VGA controller chip set and the 82C411 flat panel colour panel DAC. Dolch uses a proprietary algorithm to convert DVI resolution video to VGA in video real time. The DVI system is fully compatible with IBM EGA, CGA, MDA and Hercules graphic standards. The DVI option is also supported under MS-DOS, Unix and OS/2 operating systems. Recently, Dolch has also introduced a JPEG-compatible compression capability for its portables, providing instant recording and playback to and from the hard drive. This option conforms to the MPC standard championed by Microsoft Corp, and includes its Multimedia Extensions for Windows, digital audio capabilities and a built-in CD-ROM drive. And finally, Dolch has added a symmetrical video compression decompression option to its PAC portable computer line, in a further bid to take over the multimedia market. The compression decompression option is based on the C-Cube Microsystems Inc CL550 single chip processor and is capable of digitising and encoding real-time video and audio, writing the data to standard system hard disk and playing the video and audio back, also at real-time rates. The C-Cube CL550 uses the JPEG standard algorithm running at video rates, with user-selectable, variable compression ratios depending on the desired bandwidth, image quality and signal source. Compression rates are user-selectable from 8:1 up to 150:1, accommodating hard disk bandwidths in SCSI as well as IDE devices. The JPEG option can accept video and audio input from a variety of sources, including NTSC, PAL and CCIR 601.
