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The latest video coding standard, high efficiency video coding (HEVC), aims to achieve better coding efficiency than the H.264/AVC standard. To improve the coding performance of HEVC, tools and structures are included that also increase the computational complexity of encoding, especially for the mode decisions in the coding unit (CU), which is a structural element in the HEVC. For each CU size, the HEVC encoder performs mode decision and motion estimation using all prediction unit (PU) types and incurs massive computational burdens. In this paper, we investigate the depth correlation between the current and the collocated CU to avoid irrelevant CU procedure and truncate some PU predictions as a result. We also investigate the relationship of the rate-distortion (RD) costs after the Merge/SKIP prediction. By analyzing different CU sizes and quantization parameters, we build a mathematical model to represent the relationship for the RD costs after the Merge/SKIP prediction with an adaptive termination of the CU procedure. In addition, the relationship of the RD costs after the Merge/SKIP prediction and 2N \boldsymbol \times 2\textN mode is also explored. Search range reduction is used to further speed up our algorithm. Experimental results show that our algorithm can reduce the coding time by up to 80%, and provide average coding time savings of 46%, 45%, and 52%, for low delay B, low delay P, and random access configurations, respectively. Moreover, the proposed algorithm is able to maintain coding performance similar to HM 11.0. The proposed scheme outperforms previous work in terms of both the coding speed and the RD performance. [ABSTRACT FROM PUBLISHER]

Abstract: Multi-view video coding (MVC) has been extended from H.264/AVC to improve the coding efficiency of multi-view video. This paper proposes a fast mode decision algorithm which can make an early decision on the correct mode partition to solve the issue of the enormous computational complexity. The best modes of the reference views are utilized to determine the complexity of the macroblock (MB) in the current view, the mode candidates needed to be calculated can then be obtained according to the complexity. If the complexity is low or medium, the search range can be reduced. The threshold of the rate-distortion cost for the current MB is calculated using the co-located and neighboring MBs in previously coded view and is utilized as the criterion for early termination. The motion vector difference in the reference view is applied to dynamically adjust the search range in the current MB. Experimental results prove that the proposed algorithm achieves a time saving of 81.05% for a fast TZ search and 87.85% for full search, and still maintains quality performance and bitrate. [Copyright &y& Elsevier]

Multiview video coding (MVC) has attracted great attention from industries and research institutes. MVC is used to encode stereoscopic video streams for 3D playout systems such as 3D television, digital cinema, and IP network applications. MVC is an extended version of H.264/AVC that improves the performance of multiview videos. Yet, when compared with single-view video coding, MVC consumes much more time when encoding large amounts of data. Speed-up algorithms, therefore, are essential for realizing related applications. This paper presents a fast mode decision algorithm to avoid the high computational complexity of MVC. The proposed approach aims to reduce candidate modes and make mode decision process more efficient. The minimum and maximum values of rate-distortion cost (RD cost) in the previously encoded view are used to compute a threshold for each mode in the current view. Compared with joint multiview video coding, the experimental results demonstrate that the proposed algorithm provides an average of 79% in time savings with negligible bit rate increase and peak signal-to-noise ratio decrease. [ABSTRACT FROM PUBLISHER]

This paper presents a strategy that efficiently allocates the limited resource and still maintains the coding performance for the spatial scalability of H.264/SVC. An integrated computation-scalable algorithm is proposed on the basis of priority-based mode decision (PBMD) and activitybased motion estimation (ABME). The rate-distortion cost (RD-cost) of base layer is utilized as the priority to decide the mode in the enhancement layer, and the motion vector difference (MVD) in the base layer is employed to determine the search range as well. Through the proposed approach, computation complexity of the enhancement layer could be reduced efficiently and well allocated. A fast algorithm with early termination mechanism is also proposed in this paper. Experimental results demonstrate that the various ratedistortion and time-saving performances with computation scalability are realized. [ABSTRACT FROM AUTHOR]

Scalable video coding incorporated with computation-aware ability achieves quality as well as being computation scalable. This paper presents a computation-aware algorithm for scalable video coding with spatial/quality scalability aiming for the best trade-off between rate distortion performance and computational consumption. We first observe and analyze and then establish a model for the motion vector difference relationship between the scalable base and enhancement layers. By using the modeling results, a linear algorithm for computation distribution is thus proposed to allocate the computation for each macroblock in the enhancement layer. In addition, the rate distortion costs of the base layer are also taken into account for the computation allocation process in order to further improve the coding performance. The simulation results demonstrate that our proposed computation-aware algorithm not only accomplishes better rate distortion performance than other works under the same computational constraints, but also achieves less computation necessities. [ABSTRACT FROM AUTHOR]