Second Order Wedgelets in Image Coding

In these days efficient image coding plays a very important role. There are well known and recognized theories concerning this topic such as wavelets or new and recently developed ones as geometrical wavelets. The latter one, thanks to the possibility of catching discontinuities in different locations, scales and orientations better reflects the Human Visual System than classical wavelets. In the paper we proposed the improvement of the algorithm used in image coding based on wedgelets - a kind of geometrical wavelets. The proposed algorithm is based on second order wedgelets which are based not only on straight edges but also on fragments of second degree curves in order to ensure more sparse approximation of an image in rate distortion sense. The performed experiments confirmed that the use of second order wedgelets ensures better compression properties in image coding than the use of wedgelets.

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