Video artist Juan Downey is walking through the Amazon jungle with two Yanomno Indians. Suddenly they turn on him, pointing a loaded shotgun and bow and arrow at him. He aims his video camera back at them, filming steadily. Finally, laughing, they lower their weapons.

"The camera is also a dangerous weapon," Downey remarks.

With luck, the National Video Festival being held here all this week at the Kennedy Center will alert a whole new audience that video is a weapon, a confession booth, a diary, a palette.

Yesterday's opening session had charming soliloquy bout drawing nudes on the video screen, a giggly and dated I'll-film-you-and-you-film-me duet by two coy ex-lovers and a series of straight-on self-interviews called Love Tapes.

It was the last, a half-hour tape by Wendy Clarke, that drew strong applause from the knowledgeable audience, vanguard of the video-freak crowds from all over the country that are expected here later in the week. Clarke gave her subjects three minutes each to talk about love. They were set in front of a camera, alone, with backdrop and music of their choosing. Then they talked.

The first reaction is: Oh Lord. Yet another self-important Student of Human Nature. But it grows on you. The people, a young black man, an elderly teacher, a former showgirl, a gay man, a girl newly in love, really open up. They reveal themselves in their words, their self-conscious smiles and the quick, real smiles that follow after. Some are taken by surprise when the three minutes end. Some say they had planned to wind up another way. wSome just face the camera, the unknown audience and the future, confronting all.

It seems tha this tape resembles video itself: It perfectly expresses the American faith that quantity and quality are the same thing. In the hands of an artist, it works. The style of the great chess thinker Wilhelm Stenitz has been described as "the accumulation of small advantages": irritating, eccentric and dull -- but he won. Video is like that. If you don't die from boredom, you are apt to learn something.The boredom of video is the boredom of life, and when it is great, it is great the way life is: unexpectedly.

It's not just the cinema verite, either. Nam June Paik's wild montage of Olympic skaters, dancers and other action, shown in polarized color through inhabited goldfish bowls, may draw a laugh or two, but is is gorgeous and exciting and anyway, what's the matter with laughter?

The main problem of video today, it appears, is prying itself loose from film. So many people think it is a form of cinema and insist on seeing it that way--just as movies used to be seen as a kind of flat theater. There is also the love-hate relation to network TV: a market, a source of money, yet something to be separate from when possible. Hence the euphemism "video." y

Way back in the '20s, archy the cockroach-prophet wrote: mehitabel the cat says she is not scared by the cleanup in the moving pictures cheer up says mehitabel television is coming some time and who knows but what television will be lousy and enjoyable and by the time television is cleaned up the pictures will get immoral again . . . --"the lives and times of archy and mehitabel," by Don Marquis, Doubleday.

Archy got a lot of things right, but he missed the boat on video, which may really be the wave of the electronic future.