An efficient biprediction decision scheme of high efficiency video coding (HEVC) is proposed for fast-encoding applications. For low-delay video applications, bidirectional prediction can be used to increase compression performance efficiently with previous reference frames. However, at the same time, the computational complexity of the HEVC encoder is significantly increased due to the additional biprediction search. Although a some research has attempted to reduce this complexity, whether the prediction is strongly related to both motion complexity and prediction modes in a coding unit has not yet been investigated. A method that avoids most compression-inefficient search points is proposed so that the computational complexity of the motion estimation process can be dramatically decreased. To determine if biprediction is critical, the proposed method exploits the stochastic correlation of the context of prediction units (PUs): the direction of a PU and the accuracy of a motion vector. Through experimental results, the proposed method showed that the time complexity of biprediction can be reduced to 30% on average, outperforming existing methods in view of encoding time, number of function calls, and memory access.
For the higher coding performance than the previous video coding standards, high
efficiency video coding (HEVC) adopts an angular intra prediction method, which
requires heavy computational complexity due to the increased intra prediction
modes. In this paper, we propose a fast intra prediction mode decision based on
the estimation of rate distortion cost using Hadamard transform to reduce the
number of intra prediction mode and early termination whether the current coding
unit is splitted or not. The experimental results show that the proposed method
reduces the computational complexity of intra prediction in HEVC and achieves
similar coding performance to that of HEVC test mode 2.1
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.
This paper presents a new automatic target detection (ATD) algorithm to detect targets such as battle tanks and armored personal carriers in ground-to-ground scenarios. Whereas most ATD algorithms were developed for forward-looking infrared (FLIR) images, we have developed an ATD algorithm for charge-coupled device (CCD) images, which have superior quality to FLIR images in daylight. The proposed algorithm uses fast binary template matching with an adaptive binarization, which is robust to various light conditions in CCD images and saves computation time. Experimental results show that the proposed method has good detection performance.