A fast mode decision algorithm is proposed to reduce the computation complexity of adaptive inter layer prediction method, which is a motion estimation algorithm for video compression in scalable video coding (SVC) encoder systems. SVC is standard as an extension of H.264/AVC to provide multimedia services within variable transport environments and across various terminal systems. SVC supports an adaptive inter mode prediction, which includes not only the temporal prediction modes with varying block sizes but also inter layer prediction modes based on correlation between the lower layer information and the current layer. To achieve high coding efficiency, a rate distortion optimization technique is employed to select the best coding mode and reference frame for each MB. As a result, the performance gains of SVC come with increased computational complexity. To overcome this problem, we propose fast mode decision based on coded block pattern (CBP) of 16×16 mode and reference block of best CBP. The experimental results in SVC with combined scalability structure show that the proposed algorithm achieves up to an average 61.65% speed up factor in the encoding time with a negligible bit increment and a minimal image quality loss. In addition, experimental results in spatial and quality scalability show that the computational complexity has been reduced about 55.32% and 52.69%, respectively.
A simple and effective method is presented for fast decoding of H.264 scalable video coding (SVC). The up-sampling operation in H.264 SVC makes the decoder very complex, because convolution and complex memory transactions are inevitable. The proposed method exploits coded modes of neighboring macroblocks (MBs) for determining up-sampling operation on MB by MB. The experimental validation shows considerable improvement in decoding time, and the proposed method reduces the complexity by about 25% on average.
In universal media access (UMA) environment, because of the heterogeneous networks and terminals, flexible video adaptation, that is performed according to the network conditions and terminal capabilities as well as user preferences, is required to maximize consumer experience and ensure Quality of Service (QoS). MPEG-21 Digital Item Adaptation (DIA) support an interoperable framework for effective and efficient video adaptation. Among MPEG-21 DIA tools, utility function that describes the relations among the feasible adaptation operation, resource constraint, and utility plays the most important role in adaptation process because the optimal adaptation operation is decided among the feasible adaptation operations with given constraints. Therefore, in this paper, the overall concept of MEPG-21 DIA based adaptation framework and formulation of utility function are presented. In addition, the feasibility of the adaptation framework is presented by applying it to a few use cases for generating utility function and applications to specific adaptation scenarios involving nonscalable and scalable video.
Technical advance in creating, storing digital media in daily life enables computers to capture human life and remember it as people do. A critical point with digitizing human life is how to recall bits of experience that are associated by semantic information. This paper proposes a technique for structuring dynamic digital object based on MPEG-21 Digital Item (DI) in order to recall human’s memory and providing interactive TV service on family tree albuming system as one of its applications. DIs are a dynamically reconfigurable, uniquely identified, described by a descriptor language, logical unit for structuring relationship among multiple media resources. Digital Item Processing (DIP) provides the means to interact with DIs to remind context to user, with active properties where objects have executable properties. Each user can adapt DIs’ active properties to tailor the behavior of DIs to match his/her own specific needs. DIs’ technologies in Intellectual Property Management and Protection (IPMP) can be used for privacy protection. In the interaction between the social space and technological space, the internal dynamics of family life fits well sharing family albuming service via family television. Family albuming service can act as virtual communities builders for family members. As memory is shared between family members, multiple annotations (including active properties on contextual information) will be made with snowballing value.
Imperceptibility and robustness including complexity are important
issues in watermarking system, so it is desirable to consider
these issues on design of watermarking system. In this paper, we
will propose one of video watermarking in which motion between
three continuous frames is utilized in order to provide the
imperceptibility, robustness and acceptable complexity. Region <i>R</i> for watermarking is retrieved from three frames <i>f</i>(<i>t</i>), <i>f</i>(<i>t</i>+1) and <i>f</i>(<i>t</i>+2), and the watermarks which conveys a payload of <i>L</i> bits are embedded into DCT coefficients of Region <i>R</i>. Experimental results show that the proposed method could provide good fidelity and the robustness against MPEG-2 compression as well as some frame attacks.