With the advancement of network and multimedia technologies, many computer convergence applications have emerged. Digital signage via the Internet is one of the innovative uses adopted by the commercial industry. Commercials are a part of our daily lives, for instance, indoor and outdoor digital signs can be found in department stores and baseball parks, respectively. For a new media or commercial advertisement channel, it is important to measure and monitor its effectiveness. Here, we use data mining to investigate the results of digital advertising in broadcasting through the digital signage system. In this study, we aimed to understand the effectiveness of digital signage - whether its advertisement attracts the target customers. Based on the commercial programs requested by clients, we used face recognition and data mining technologies to recognize the facial features of customers from different angles when facing the display screen. Then we determined whether a consumer is watching advertisements and tracked the viewing duration. Lastly we analyzed the obtained data to evaluate the effectiveness of the digital signage advertisement. Our experiments show that our approach is feasible and can meet users¡¦ expectations.