kiptroniclogo.bmpKiptronic, a San Francisco company that lets publishers insert ads into audio and video files before they are downloaded for listening on a device, has raised $4 million in a first round of funding.

The investment was led by Blueprint Ventures and Prism VentureWorks.

Kiptronic’s technology works on files that are downloaded onto mobile phones, iPods and PCs for listening to later off-line. This is referred to as “podcasting,” and differs from video “streaming” process, whereby someone gets a broadcast on their phone via a cellular or broadband network. There are plenty of other ad-insertion companies serving that market.

Podbridge, a company backed by Mayfield and Worldview, is doing something very similar (see our review here) to Kiptronic.

Kiptonic, however, doesn’t require a software download. Podbridge does; and when a user registers, they fill out a form allowing Podbridge to get the person’s demographic and other details, to better target ads.

People prefer not to download a software to their device, Bart Schachter, a venture capitalist with Blueprint, tells VentureBeat. Kiptronic may relinquish lots of potential information about a user, but Schachter says Kiptronic can still pick up location information about a user (by tracking IP addresses) when users download files, and can look at what they’re downloading to find out more about the person’s tastes. Moreover, he says many people provide false information when filling out forms like Podbridge’s.

Kiptronic works with Akamai, a so-called “content delivery network,” which allows Kiptronic’ s software to insert ads for a publisher without any additional steps. Kiptronic’s ad server sits in the network.

The company is growing quickly. It supported 47 million downloads in the fourth quarter, and is growing quickly, Schachter said.

The company has seven employees, and that number will double over the next few weeks, Schachter said.