db@cs.ed.ac.uk (Dave Berry) (01/09/91)
The Amiga Centre Scotland have asked me to post some information about their new 24-bit graphics board. I have no connection with them apart from this, and I don't understand video technology, so please direct all enquiries to them. The board is an internal Zorro II compatible card for the Amiga 2000/3000. It has a 32-bit architecture and comes in four models: Harlequin 1500: 1.5M RAM Harlequin 2000: 2M RAM + Alpha Channel Harlequin 3000: 3M RAM + Double Buffering Harlequin 4000: 4M RAM + Alpha Channel + Double Buffering. All models may be upgraded to later ones. Other upgrades avaliable include a Video Framegrabber and a CCIR 656 Interface for 601 Digital Video. The board is compatible with other accessories such as Single Frame Controllers, Film Recorders, Harlequin Genlock, PAL Encoders, Video Printers and Input devices such as Tablets. The board produces RGB + Composite Synchorous output (pk-pk 75 ohm), plus Genlock I/O Control lines and Digitial Key output. It supports both PAL and NTSC. Resolutions provided are: PAL: 740x576 NTSC: 740x486 832x576 832x486 910x576 910x486 Vertical Horizontal interlaced non-interlaced PAL: 50 Hz 15.625 KHz 31.25 KHz NTSC: 60 Hz 15.734 KHz 31.50 KHz The board is supplied with a programmer's interface "allowing full access to all its features", including an Amiga device driver, an Amiga library, and a manual for the Harlequin. It also comes with software for displaying IFF files, plus output from Real 3D, Sculpt-Animate, Scanlab "and many more". Software switches are provided for setting the horizontal resolution, interlaced/non-interlaced, buffer accessed, buffer displayed, and separate RGB and Alpha Channel on/off. The Double-Buffering option means that two images are available and can be updated separately. "This is essential for real-time, smooth animation, for effective slide-show displays and to implement undo options in paint software". The Alpha Channel option refers to the extra 8 bits of the 32-bit architecture beyond the 24 bits used to store images. It can be used to provide 256 levels of linear keying for anti-aliasing, or can be used to allocate a single bit-plane as a digital key output for cutting between Harlequin graphics and other video sources, or for multiple masks or a Z-buffer. That's all the information I have. I don't know how this compares to other boards on the market. I also don't know the final price: all I've heard is the phrase under #2000 (two thousand pounds), but I don't know which model that referred to. I believe that the board is available now. For further information, please contact: Amiga Centre Scotland, 4 hart St. Lane, Edinburgh, EH1 3RN, Scotland. Tel: +44 (0)31 557 4242 Fax: +44 (0)31 557 3620 (Ignore the 0 in these numbers for international calls.) -- Dave Berry, LFCS, Edinburgh Uni. db%lfcs.ed.ac.uk@nsfnet-relay.ac.uk