Media and marketing research firm Arbitron Inc. has signed an agreement with digital signage software provider BroadSign International, to deliver a proof-of-play advertising audit service using the Portable People Meter (PPM) technology.

Arbitron will use its PPM to conduct a series of annual audits capturing when encoded audio and video advertising content is displayed on networked digital screens in 50 random BroadSign-run locations across the United States. The data will be compared with the BroadSign commercial schedule logs.