SAN JOSE, Calif. -- A week-long festival called "ZeroOne" is expected to draw 50,000 people to downtown San Jose this week.

One of the biggest draws of the week began Tuesday night at San Jose's city hall. An artist used 15 projectors to light up the rotunda beginning at 9:30 p.m. The display will continue every night this week through Friday.

The festival also showcases some very unusual inventions.

ZeroOne is an interactive mix of art and technology.

Zero One Preparations
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NBC11's Daniel Garza was on hand for last-minute preparations on Sunday. Garza said in order to get work shown this week, an artist must be innovative and a near expert in digital technology.

Artist Will Pappenheimer is one of the artists taking part in the festival. He calls his work a public mood ring. It measures a person's emotional reaction to a single news story and then translates the reaction into colors.

The color is projected onto an awning inside the museum of art.

Pappenheimer said, "The color is really the result of both a public issue and a person searching it. It's the relationship of us to news because that's one of the big things now."

Another presenter at the festival is a researcher from U.C. Irvine. His project is a bit more scientific. Beatriz da Costa told NBC11 he plans to attach tiny backpacks to a flock of pigeons in order to measure smog above downtown San Jose.

The measurements will be made public in an online blog.

The pigeons took their first flight Tuesday.

Another project is a mix of art and technology. An artist created a display using 24,0000 tiny lights, and he is displaying his work on top of the Adobe headquarters in San Jose.

The circles react to noise. They spin faster when airplanes fly by.

NBC11's Garvin Thomas featured a performer that calls his display "San Jose Voices". He set up a phone number where anyone can call in and leave a one minute message. The messages are recorded and then played in public as the man rides his bike around the streets of San Jose this week. The phone number to call in is 408-916-1033. Here is a link to the San Jose Voices Web site.

The festival goes through Friday.