Google acquired AdMeld, a firm that specializes in ad optimization and ad inventory for publishers, according to several reports.

AdMeld gives publishers the ability to get the best prices for their ad inventory. The New York-based company helps publishers choose their ad buys across dozens of advertising networks and get the best price possible.

Google is apparently willing to pay a lot for AdMeld’s technology and customers: around $400 million, according to The New York Times.

The Deal would expand Google’s advertising business markedly, taking it beyond its usual text ads to those including images and video. “Admeld’s mission is to keep premium publishers on the cutting edge of advertising technology, enabling them to maximize their revenue and sell their inventory smarter and safer,” Admeld says on its website.

However, this acquisition is likely to undergo heavy scrutiny from government regulators, as Google is already the dominant force in text and display advertising.

Admeld was founded in 2007 and is based in New York City, with other offices in San Francisco, London, Berlin and Toronto. On its website, the company lists current clients as Answers.com, Fox News, IDG TechNetwork, Hearst Television, Discovery, The Weather Channel and “more than 500 others worldwide.”