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In this paper, a new mixture model for image segmentation is presented. We propose a new way to incorporate spatial information between neighboring pixels into the Gaussian mixture model based on Markov random field (MRF). In comparison to other mixture models that are complex and computationally expensive, the proposed method is fast and easy to implement. In mixture models based on MRF, the M-step of the expectation-maximization (EM) algorithm cannot be directly applied to the prior distribution \piij for maximization of the log-likelihood with respect to the corresponding parameters. Compared with these models, our proposed method directly applies the EM algorithm to optimize the parameters, which makes it much simpler. Experimental results obtained by employing the proposed method on many synthetic and real-world grayscale and colored images demonstrate its robustness, accuracy, and effectiveness, compared with other mixture models. [ABSTRACT FROM PUBLISHER]

Multi-view video plus depth format, which includes texture and depth images, has been recently introduced as a video representation to support depth perception of scenes and efficient view generation at arbitrary positions. Especially, a depth image has been one of the significantly important issues for successful services of 3-D video applications. In this paper, we introduce a fast and efficient multi-view depth image coding method using the texture images. The proposed method determines to skip some blocks of the depth image at the early stage without a normal encoding process including rate-distortion optimization, based on temporal and inter-view correlations between the previously encoded texture images. The skipped blocks are predicted from the neighboring depth images. Experimental results demonstrate that the proposed method not only achieves the drastically high coding performance but also reduces the complexity of the encoder. [ABSTRACT FROM AUTHOR]

Reference picture selection (RPS) is a powerful error-control technique for video streaming. Previously, two fast block-based motion vector concatenation (MVC) algorithms were proposed for video transcoding based on forward dominant vector selection (FDVS) and activity dominant vector selection (ADVS). In this paper, we cast these algorithms in the rate-distortion (RD) optimization framework. We also present two novel RD optimized pixel-based MVC schemes for RPS. Experimental results indicate that the proposed methods provide higher video quality compared to both FDVS and ADVS. In addition, we study the complexity of various RPS algorithms as a function of the loss rate and round trip time. [ABSTRACT FROM AUTHOR]

This paper presents a new video compression framework over H.264/AVC scheme that integrates our proposed structured priority belief propagation (BP)-based inpainting prediction (IP) to exploit the intrinsic nonlocal and geometric regularity in video samples. Unlike the existing edge-based inpainting adopted in lossy image coding, the optimal predictor could maintain the pixel-wise fidelity and the robust error resilience without any assistant information. Beyond the local prediction limitation of traditional intra and inter-modes, the priority BP with regularized structure priors of a spatio-temporal Markov random field is imposed on the predictor in an adaptive and more convergent sense. Specifically, the structured sparsity of the predicted macroblock region is inferred by tensor voting projected from the co-located decoded regions. In turn, the priority and visiting order of nodes are assigned according to the sets of updated beliefs as the propagation of messages. Through relatively few iterations of forward and backward process, the sparse inference of priority BP would ensure a stable marginal belief distribution on the structure and texture through updating local messages and beliefs. Within the optimal mode selection on rate-distortion optimization (RDO), the IP-mode with structured priority BP outperforms the existing vision-based approaches, and specially achieves a better objective rate-distortion performance besides visual quality. The IP-mode with structured priority BP can be applied to both I and P frames to generate low entropy residue, e.g., homogeneous visual patterns, and the computation complexity is also competitive with one iteration of sparse inference. Moreover, it behaves more resilient with an intrinsic probabilistic inference than the intra and inter-modes. [ABSTRACT FROM AUTHOR]