OSAKA--Passengers on a train nearing Fukushima Station here might think a peculiar arrangement of black-and-white numbers and alphabetic letters on roofs could be the work of paranormal activity or UFOs.

But the mysterious patterns seen along the outer track along the JR Osaka Loop Line between tall buildings are works known as roof art, under which images are depicted on the tops of buildings visible from trains.

The art campaign was started by Takuya Yoden, 46, an artist in Sakai, in 1994, when he was a student. His inspiration was based on the thought that creating artistic productions in the bland urban scenery would be interesting.

Asked by Yoden to make available the roof for his activity free of charge, Katsuyasu Kusazumi, 64, manager of a local uniform shop, became the first to accept the request.

Kusazumi said he felt sympathy for Yoden, because he loves music so much that he frequented a music pub in Osaka's Umeda district during his school days.

"A youngster who wanted to 'move the world' was in trouble because he did not have places to show his works," said Kusazumi. "We must provide chances for such a guy."

As more people offered their roofs for art pieces, Yoden started in 1997 to show encrypted messages of the building owners on the rooftops.

"I wanted to form bonds with the owners in ways other than simply using their housetops," said Yoden. "I would like viewers to imagine the feelings of people under the roofs."

Late last year, Yoden set up his first artistic production in nine years on Kusazumi's store. The work from what Yoden calls the K-word series is comprised of a square frame and 14 characters within, and resembles a QR code in appearance.

If the shown letters are entered on a keyboard in the hiragana input mode and rearranged on a computer, a message stating "take it easy honestly and straightforwardly" will emerge. That is the motto of the Kusazumi family.

While another K-word production created in the past remains between Sakuranomiya and Kyobashi stations, other works consisting of four numbers each were shown on the seven homes along the Osaka Loop Line as well.