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BACKGROUND

International video coding standards such as H. 261, MPEG-1, MPEG-2 Video, H. 263, MPEG-4 Visual, and H. 264/AVC have played an important role in the success of digital video applications. They provide interoperability among products from different manufacturers while allowing a high flexibility for implementations and optimizations in various application scenarios. The H. 264/AVC specification represents the current stateof-the-art in video coding. Compared to prior video coding standards, it significantly reduces the bit rate necessary to represent a given level of perceptual quality—a property also referred to as increase of the coding efficiency. The desire for SVC, which allows onthe-fly adaptation to certain application requirements such as display and processing capabilities of target devices, and varying transmission conditions, originates from the continuous evolution of receiving devices and the increasing usage of transmission systems that are characterized by a widely varying connection quality. Scalability has already been present in the video coding standards MPEG-2 Video, H. 263, and MPEG-4 Visual in the form of scalable profiles. However, the provision of scalability in terms of picture size and reconstruction quality in these standards comes with a considerable growth in decoder complexity and a significant reduction in coding efficiency (ie, bit rate increase for a given level of reconstruction quality) as compared to the corresponding nonscalable profiles. These drawbacks, which reduced the success of the scalable profiles of the former specifications, are addressed by the new SVC amendment of the H. 264 …