Apple, in its continuing battle for decency, may now want to make sure you have pants on before you can buy anything from its e-commerce sites.

Leakers inside the company recently told Mac|Life that Apple isn't merely content to randomly police the content of apps sold in its stores. Instead, there is a new effort within the company to make sure customers of its App Store, iTunes Store and web store at apple.com are "appropriately attired" before checking out.

"This is one huge initiative," one leaker told Mac|Life. "The technologies behind this are pretty impressive."

The initiative leverages resources from across the entire company. Software engineers responsible for the facial recognition features of iPhoto, are now working on an "advanced naughty bit detection algorithm" as well as algorithms that differentiate between short shorts and boxer shorts, and between bikinis and bras.

"It's frustrating writing this algorithm, because the distinction between a bra and a bikini top are so arbitrary. Trying to put that into computer code is a challenge. I'm fudging a bit by detecting colors and drawing inferences from that."

The leaker said the algorithms could be inserted onto a later revision of the A4 chip used in the iPad. With a few revisions, Apple would be able to use ambient light sensors to determine what its App Store shoppers are wearing, and penalize people who dare to shop in their underwear by arbitrarily deleting a random song from their iPod library.

The algorithms could also be inserted into a future system update. The leaker said the algorithms would use data from the built-in iSight whenever a user visits the Apple Store by web browser, or the iTunes store, and randomly crash the computer if the algorithm didn't approve of the clothes.

In cases where the algorithm can't decide whether you've got enough clothing on, the company is also looking at a third-party solution: outsourced human decisionmakers, accessing your Apple devices through MobileMe, using a hidden feature called "CensorCloud." These people, who may be sitting in another state or country, can make "educated guesses" about what you're wearing, based on all available data, including your device's operating temperature, how much light is in the room, sound from the built-in microphone and video from built-in or attached cameras. Anyone deemed to be inappropriately dressed will be banished from Apple Stores permanently.

Apple, of course, will make exceptions for anyone "well-known ... with previously published material available broadly." They didn't have much of a problem locating someone within the company to identify well-known porn stars who would be exempt from the new initiative, our source said.