Image Downsampling and Upsampling Methods
نویسنده
چکیده
Downsampling and upsampling are widely used in image display, compression, and progressive transmission. In this paper we examine new down/upsampling methods using frequency response analysis and experimental evaluation. We consider six classes of filters for down/upsampling: decimation/duplication, bilinear interpolation, least-squares filters, orthogonal wavelets, biorthogonal wavelets, and a new class that we term binomial filters. Our findings show that binomial filters and some biorthogonal wavelet filters are among the best filters for down/upsampling, and significantly outperform the standard methods.
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