Video Finds Clear Use for Fuzzy Logic

Just by its name it’s easy to see why most people are a bit fuzzy on fuzzy logic.

But far from being anything that’s way-out, fuzzy logic is simply a way of processing information that allows video equipment to take more conditions into consideration when making adjustments in areas such as focusing, aperture settings and picture quality.

Although fuzzy logic has many applications, it’s getting the biggest push from the video industry.

Fuzzy logic describes a way of thinking about vague qualities--harmony, color, high or low, near or far, to name a few--in terms a computer can understand.

Normally, a computer can’t deal with indefinite answers because it thinks in absolute terms. For example, the typical camcorder’s auto-exposure knows when an overall scene is well-lit and when it is not. It exposes for what’s well-lit by closing down the iris. But if the main subject is in deep shade, the result is underexposure.

Fuzzy logic allows computers to deal with situations such as this that don’t yield absolute answers. In effect, computers can now understand that a quantity is “almost” something, or “not quite” something else. Also, since readings are continuously checked, the machines constantly recalibrate themselves for optimal performance.

The first camcorders with fuzzy logic-controlled exposure are Fisher’s 8-millimeter FVC-800 ($1,299.95) and Canon’s Hi8 H800 ($1,749) and 8-millimeter EO6 ($1,549).

Besides Fisher and Canon, other electronics companies, notably Sony and Panasonic, are finding imaginative uses for fuzzy-logic programming.

Sony’s effort is going into a series of large-screen TV sets. This use of fuzzy logic divides the screen into 248 reference points that are measured 60 times per second for picture quality, color, brightness and sharpness. The circuits adjust the picture against optimized levels programmed for each picture characteristic.

Panasonic is using the processing as part of a digital stabilization feature on its new palm-sized PV-40 Compact VHS camcorder ($1,299) that electronically eliminates some of the jiggle associated with hand-held shots.