MacVision For Apple Macintosh
Charles Brannon, Program Editor
Requirements: Apple Macintosh and a source for standard video images. Color or black-and-white video camera, tripod, and Imagewriter printer recommended.
MacVision is a combination of hardware and software that lets you digitize any image from a video camera, video-cassette recorder, or laser disc player. The digitized picture can be loaded into MacPaint, MacWrite, or almost any Macintosh application. It can be modified, merged with text and graphics, and printed on the Imagewriter.
The MacVision digitizing box plugs into the printer or modem port. A phono jack accepts any NTSC-standard video source. After installing the software on an application disk, it becomes part of the operating system as a desk accessory. When you select MacVision from the desk accessories menu, another menu appears in addition to whatever menus are being used by the application. The menu contains eight choices: Adjust, Scan Window, Scan Screen, Save Screen, Print Window, Print Screen, Printer, and Modem.
Printer and Modem are used to tell MacVision which port you've plugged it into. Adjust presents a vertical graph that helps you set the digitizer's brightness and contrast controls. These controls are crucial to obtaining a quality image. I found that Adjust leaves you with a well-balanced, but grainy picture. You will almost always need to fine-tune while scanning the image.
Scan Window creates a picture within a small window on the screen, taking about six seconds per scan. This option is most useful for adjusting controls or for taking casual snapshots. You can also print the window or transfer it to the Clipboard, ready to be pasted into another application. Scan Screen makes a much better picture by using the entire 512 × 384 resolution of the Macintosh. This takes 22 seconds. Then you can either dump the picture to the Imagewriter with the Print Screen option or save it on disk with Save Screen.
MacVision simulates gray scales with varying dot densities, similar to the half-tones in published photographs. The pictures seem to be about half the resolution of newspaper photos. If photo-reduced, they're almost photographic in quality. But if you're sloppy with the controls, you'll get really grainy pictures. Also, remember that your subject will have to remain perfectly still for as long as 22 seconds—longer if you're trying to adjust controls on the fly.
Once you've digitized a picture, you can paste it into MacWrite as an illustration or modify it with MacPaint. It's fun to capture a face and experiment with new hairstyles, moustaches, beards, and symmetrical analysis (where you copy half of a face vertically, flip it, and merge it back—a technique usually done with a mirror to analyze personality). I even wrote a simple game in Microsoft BASIC in which the objects bouncing around are the faces of friends.
MacVision could also be used as a security system. If two scans of a room are not identical, then something is moving. It's even conceivable that MacVision could provide the link for visual recognition. After all, Koala Technologies dubs MacVision as "vision for a visionary computer."
Koala Technologies Corporation
3100 Patrick Henry Drive
Santa Clara, CA 95052-8100