By Staff Writer – John Federico (@gadgetboy)

We’ve seen ads everywhere on the web but the one ad unit that hasn’t been effectively monetized is the humble image. No, I’m not talking about using images as ads – we’ve had those since the dawn of the commercial web. I’m referring to overlays on photos that appear in news articles and blog posts.

AdBrite tried it back in 2007 with their BritePic ad format. It appears that it’s still around but hasn’t gotten much traction. Two other startups believe that 2009 is the year to figure out this unused ad space and each brings its own approach.

Image Space Media currently touts on their home page that they’re “Now serving ads on 6,355,999 images!” using their patent pending technology.

The New York City-based company places overlay ads on the lower fourth of “images that are relevant to the content being presented.” This means images used to enhance the page editorial and excludes “logos, other ad banners, or small buttons and icons.” The ads only appear when a site visitor mouses over an image. Installation is as simple as installing a snippet of javascript.

Mountain View, California-based Pixazza takes a different approach with a focus on ecommerce:

“Pixazza is a new platform that allows shoppers to buy products from photos seen on websites of our web publishing partners. Our unique capability allows these web publishers to generate incremental revenues by “visual commerce enabling” the images that already exists on their websites.“

While it appears that Pixazza’s method is more targeted, it also appears more complex to set up. After installing a snippet of javascript on your site, Pixazza asks for the approrpriate metadata for each image. Essentially, you need to tell their system what’s in the picture so that they can find and link to it in an appropriate ecommerce environment. Participating advertisers appear to be ecommerce affiliate marketers “including Amazon, BlueFly, eLuxury, Macy’s, Shopbop, and Zappos.”

The company is privately held and backed by August Capital, CMEA Capital, and Google.

Will we see this type of advertising make its way onto the sites that you visit?

DISCLOSURE OF MATERIAL CONNECTION: http://cmp.ly/0