%0 Journal Article %T Systematic Review of Multiple Contents Synchronization in Interactive Television Scenario %A Ricardo Mendes Costa Segundo %A Celso Alberto Saibel Santos %J ISRN Communications and Networking %D 2014 %R 10.1155/2014/127142 %X Context. Interactive TV has not reached yet its full potential. How to make the use of interactivity in television content viable and attractive is something in evolution that can be seen with the popularization of new approaches as the use of second screen as interactive platform. Objective. This study aims at surveying existing research on Multiple Contents TV Synchronization in order to synthesize their results, classify works with common points, and identify needs for future research. Method. This paper reports the results of a systematic literature review and mapping study on TV Multiple Contents Synchronization published until middle 2013. As result, a set of 68 papers was generated and analyzed considering general information such as sources and time of publication; covered research topics; and synchronization aspects such as methods, channels, and precision. Results. Based on the obtained data, the paper provides a high level overview of the analyzed works; a detailed exploration of each used and proposed technique and its applications; and a discussion and proposal of a scenario overview and classification scheme based on the extracted data. 1. Introduction Multimedia systems allow the data streams integration of different types, including continuous (audio and video) and discrete media (text, data, and images). Synchronization is essential for the integration of these media [1] and is focus of researches for a long time [2, 3]. Most of these works use a common taxonomy proposed by Cesar and Chorianopoulos [4] to classify multimedia synchronization. This classification [5] is based on multimedia abstraction layers (Figure 1): in the media layer an application operates on a single continuous media stream, which is treated as a sequence of LDUs/MDUs (logical Data Units/Media Data Units); the stream layer allows the application to operate on continuous media streams as well as on groups of media streams; the object layer allows for simpler and exact specification of playout sequences, where each media object relates to a time axis and defines a sequence of events. Figure 1: Synchronization abstraction layers¡ª[ 5]. In the media layer, the intrastream synchronization deals with the maintenance, during the playout, of the temporal relationship within each time-dependent media stream, that is, between the MDUs of the same stream. In the stream layer the interstream synchronization refers to the synchronization, during the playout, of the playout processes of different media streams involved in the application and live synchronization deals with the %U http://www.hindawi.com/journals/isrn.communications.networking/2014/127142/