Abstract: The hexagonal orthogonal transform is based on modeling the mechanism of human vision transfer process,with properties of biological,pyramid structure,self-similar,and efficient,so that hexagonal image pyramid can be obtained directly.The base functions of the transform are orthogonal,self-similar and localized in space,spatial frequency,and orientation.This paper,based on the hexagonal sampling technologies and the idea of wavelet zero-tree compression,has introduced a new method of image compression that is based on hexagonal orthogonal image pyramid,and tried to apply it to transmission and manipulation under narrow band.This algorithm has such advantages as high speed and high efficiency of coding,and could compress image better than traditional algorithm based on rectangle sampling,guaranteeing given accuracy.

Key words: image pyramid, hexagon, orthogonal transform, image compression

摘要： 六边形正交变换由对人眼视觉传输机制的模拟过程所推导,具有仿生、自我类似、高效能等特性,可直接建立相应的影像金字塔。其变换的基函数具有正交性,自我类似性,并与频率域、空间域和方向相关等特性。论文以六边形图像采样技术为基础,结合小波零树压缩的基本思路,提出了一种基于六边形正交影像金字塔的影像压缩算法。该算法具有运算速度快、编码效率高的优点,在保证精度的条件下取得了比传统的基于矩形机制的压缩方法更好的压缩效果。

关键词: 影像金字塔, 六边形, 正交变换, 图像压缩