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Abstract

Image-zooming is a technique of producing a high-resolution image from its low-resolution counterpart. It is also called image interpolation because it is usually implemented by interpolation. Keys' cubic convolution (CC) interpolation method has become a standard in the image interpolation field, but CC interpolates indiscriminately the missing pixels in the horizontal or vertical direction and typically incurs blurring, blocking, ringing or other artefacts. In this study, the authors propose a novel edge-directed CC interpolation scheme which can adapt to the varying edge structures of images. The authors also give an estimation method of the strong edge for a missing pixel location, which guides the interpolation for the missing pixel. The authors' method can preserve the sharp edges and details of images with notable suppression of the artefacts that usually occur with CC interpolation. The experiment results demonstrate that the authors'method outperforms significantly CC interpolation in terms of both subjective and objective measures.
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... As a result, undesirable artifacts such as blurring, blocking and ringing around edges tend to occur frequently [7]. To remedy these disadvantages, several adaptive image interpolation methods have been proposed and applied to different image superresolution scenarios in recent years [8][9][10][11][12][13][14][15][16]. Missing pixels in HR images are estimated by using edge information in LR images, i.e., geometric regularity, which refers to the smoothness constraint along the edge orientation as opposed to the sharpness constraint across the edge orientation [14]. ...
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... 多的采样值, 则我们可构造对 6 ...
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