Hoi-Kok Cheung

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—In this brief, a new local motion estimator is proposed which can accurately estimate motion activities under varying strong brightness conditions. The proposed estimator makes use of a new block division technique which manages practically to get rid of the adverse influence caused by brightness changes between frames. We also propose a new static sprite(More)
—Conventional motion estimation does not take inter-frame brightness variations into consideration, which causes inefficient video coding for sequences involving brightness variations. H.264 provides a specific mode called weighted prediction targeting to improve the coding efficiency for this case. In this paper, we propose a Retinex based motion(More)
Conventional block based motion estimators assume constant inter-frame object brightness. Pixel discrepancy is resulted primarily from motion factor without considering the influence of brightness changes. In this paper, we propose a simple and efficient windowing technique using the Hamming window and integrate it to our previously proposed algorithm. The(More)
—Conventional coding system using translation only motion estimation and compensation system cannot efficiently handle complex inter-frame motion activity including scaling, rotation and various forms of distortion. In this paper, we propose a local affine motion prediction method, which manages to enhance the inter-frame image prediction quality using the(More)
A new block-based local motion estimator independent from illumination variation is presented in this paper. Conventional motion estimator relies on an assumption that the difference between images is solely resulted from the motions activities. This hypothesis ignores another possibility that variation in the contents of image can be a result of the(More)
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