In downtown San Jose atop Adobe's Almaden Tower, is Adobe's San Jose Semaphore.
The revolving four circles are symbols that are transmitting a message.
Since 2006 the software company has transmitted two codes. Now, a new code is waiting to be solved.
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Valerie Tu is a graduate student at Santa Clara University, getting her master's and teaching credential in math.
"A semaphore is mainly a method of communication -- a visual communication," Tu said.
On Adobe's Blog, the company explains how the visual transmission works.
The wheels turn to a new position every 7 seconds. Together the four wheels have 256 possible combinations.
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"I think one key thing we want to remember is pattern recognition is definitely key and also one thing patience," Tu said.
It took the last person four-and-a-half-years to solve the previous code. He was a high school math teacher from Tennessee.
If you're up to the challenge to solve the mystery message, you can see it in person or through a live web stream. A soundtrack goes along with the transmission.
"I think it's just an amazing way to connect everyone within the community either in San Jose or even online. They're web streaming it online live for everyone. And it's really- are you in the know? Are you not in the know? It's a whole game like an inner circle game that everyone can partake in," Tu said.