Image-recognition software keeps kitty's kills outside.

Squirrel the cat lives outside of Seattle with his owner, Boris Tsikanovsky. Squirrel, with sleek black and white fur and bright green eyes, looks like a normal cat. He plays inside the house with his scratch toy, and lounges on windowsills in the sun. He sometimes catches himself a bird, mouse, or even a great big rat -- dead or dying treasures his owner makes him keep outside with the help of tech, as "Tech Live" reports tonight.

When Squirrel attempts to bring his prized catch into the house to show Tsikanovsky, or to play with his captive friend for a few hours before he goes in for the kill, Squirrel runs into a little problem. If he tries to carry something in his mouth as he goes through his cat door, the door won't open, and he can't come inside.

Tired of finding animal surprises in his home, Tsikanovsky decided technology might help him keep critters other than Squirrel outside where they belong. So he developed image-recognition software to keep the cat door closed.

Every time Squirrel tries to enter the house, a box Tsikanovsky calls the Flo Control Box takes a snapshot of the cat attempting to pass through the door. Tsikanovsky named the box after his former pet Flo, notorious for bringing creatures indoors.

The system consists of a planter box, an old mailbox, a webcam, a mirror, a light, and an off-the-shelf door with a latch. Putting them all together, Tsikanovsky created the ultimate cat door.

"There is a light on one side, and a camera on the other. The camera sees the profile of the cat," said Tsikanovsky, explaining how the system works.

The camera takes a picture of the cat as a black silhouette against the white light, and a computer program Tsikanovsky wrote compares that image to a previously approved image of Squirrel without a mouse or bird in his mouth.

If the image matches an image of solitary Squirrel coming or going into the house, the cat door will open and close with ease. If the image does not match lone Squirrel and an object or unknown creature appears in the cat's mouth, the door won't open. The door also won't open if the creature trying to gain entry does not match Squirrel.

Tsikanovsky explained that in the past, Squirrel has repeatedly tried to bring in a bird only to be denied at the door.

"He was denied three times in a row," Tsikanovsky said.

Anyone can monitor the cat's adventures in and out the door on Tsikanovsky's website for Quantum Picture, where the drama unfolds live for the world to see.

Tsikanovsky based the idea for the Flo Control Box and his software company, Quantum Picture, on the concept that any image is a collection of a finite number of discrete features. Developing a Web-based search engine that uses an image-recognition algorithm to find online matches is one of Tsikanovsky's goals.

The Flo Control Project is Tsikanovsky's way of testing his theory of advanced image recognition with the built-in bonus of preventing Squirrel from peppering the house with trophy rats.

For now, Squirrel remains Tsikanovsky's lab cat, testing the system that may let the cat play, but definitely keeps the mice away.