In a digital video broadcast system, a headend component uses Quadrature Amplitude Modulator (QAM) devices or Internet Protocol (IP) services to deliver audio/video (AV) content to a set-top box as a Moving Pictures Expert Group (MPEG) stream. The MPEG stream may include “live” advertisements or targeted advertisements. The targeted advertisements are placed in a parallel QAM or an IP service that is synchronized with the “live” advertisements. Alternatively, the targeted advertisements may be stored on a data storage device that is either integrated with the set-top box, or accessible via a network communication connection. Software on the set-top box that includes a digital video recorder (DVR) determines whether to perform a switch to the targeted advertisement based on various traits, such as demographics, purchase history, observed behavior, or the like.
Multiple System Operator (MSO) customers are developing and deploying targeted advertising systems. These systems enable a set-top box to switch from a network service to an addressable advertising service, and back to the network service during an advertising break. The term “switch” includes the definition of “switch” in the context of the American National Standard (ANSI) Society of Cable Telecommunications Engineers (SCTE) Standard ANSI/SCTE 138 (i.e., switch describes tunes (L0 switch) and splices (L1 switch)), the definition of “tune” in the context of a QAM device, and the definition of “switch” or “transition” in the context of an IP or DVR device. In the first phase of deployment, the delivery of the network service and addressable advertising services are on separate transport streams, in which the addressable advertising content is synchronized with an advertisement on the network service. Since multiple advertisement streams are simultaneously delivered to the set-top box, the set-top box selects one of the advertisements, based on received information and locally stored selection criteria, and switches at the appropriate time.
The addressable advertisements contain filler, as defined in ANSI/SCTE 138. The filler follows signaled switch points which mark an opportunity to switch from the network service to the addressable advertising service, and an opportunity to switch from the addressable advertising service back to the network service. The filler is properly formatted frames that represent black pictures and silent audio, and that optimize the service acquisition procedure by allowing the set-top box the time necessary to switch to and begin decoding the new service. The duration of the filler is selected to allow for the time needed for the slowest set-top box in the network to switch to and begin decoding the new service. Since the duration of the filler is lost on the switch to the addressable advertising service and on the switch back to the network service, the duration of the filler takes away from the duration of the addressable advertising content. There is a need to minimize the duration of the filler and maximize the duration for the addressable advertising content. The presently disclosed invention satisfies this demand.