基于小波变换的能量和方差分析图像压缩方法

在对图像进行小波包分解的基础上实现图像压缩.根据小波系数的分布特点严格推导得出:可以用能量和方差作为衡量小波系数重要性的标准,并据此对系数矩阵块进行选择分组,自适应地进行量化,而且不同的量化方式可以共用码表;对低频部分扰动足够小的区域取均值,结合提出的存储方法,在不引入误差的情况下减少了编码负担,在保证图像质量的同时有效提高了压缩比.

Image Compression Based on Energy and Variance Analysis of Wavelet Transform

The image is compressed efficiently based on the wavelet packets decomposition.We can conclude that energy and variance can be served as the criterion which can be used to judge the importance of the coefficients through strictly deduction based on the character of the wavelet coefficients;these coefficients can be classed according to the criterion;after that they should be quantified adaptively;further more different methods of quantization can use the same code table.Some part of low frequency can be substitute by their averages when they have tiny difference,the compression ratio can be improved by certain storage when the quality is guaranteed.