The company has traditionally sold photographs to the press and advertising industries. Now it is looking to target consumers through a series of retail channels, including the high street.
The appointment of DDB, following a competitive pitch, will see Getty's advertising, branded content, online and direct marketing brought under one agency.
Getty's move into the consumer market is part of a growing trend in the sector.
In July two US photography firms - Eastman House and the International Center of Photography - set up a joint venture, photomuse.org, giving access to a digital archive of 200,000 photos.
Getty and rivals Corbis and JupiterMedia have spent the past four years buying up smaller competitors.