Image interpolation is an important technique of image processing. The blur and jaggy of image details or edges are inevitable during conventional image interpolation. In order to obtain interpolation images with better quality, the improved bilinear interpolation method with adaptive direction is applied to the image. Wavelet is implemented to provide more high frequency information, post-processing is applied to improve the visual quality of interpolation images. The experiments show that the interpolation images have much clearer edge, and much smoother along their direction. The results effectively remove the jaggy and blur at the edge. The subjective quality and visual effect of images interpolated using the proposed method have obviously improved, which is more in accord with the human visual system characteristic.
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