一种基于EZW改进算法的图像压缩方法研究  

Research on the method of image compression based on improved EZW algorithm

作　　者：牛德智[1] 陈长兴[1] 王曙钊[1] 张明亮[1] 陈芳[2] 

机构地区：[1]空军工程大学理学院,陕西西安710051 [2]空军工程大学训练部,陕西西安710051

出　　处：《电子技术应用》2010年第12期128-131,共4页Application of Electronic Technique

基　　金：国家863资助项目(No.2007AAJ129);陕西省电子信息综合集成重点实验室资助项目(No.200906B)

摘　　要：针对原EZW算法未能很好利用图像小波系数特点及按照频率特性量化小波系数的不足,提出了对图像小波系数进行信噪分离、阈值化处理以及对低、高频图像信息进行分阈值量化的改进算法,并给出了在保证复原图像质量情况下扫描终止的判别条件,以节省压缩时间,在实时传输中能有效地提高图像压缩效率。仿真实验结果表明,改进算法无论在扫描相同次数下的信噪比,还是相近信噪比下的压缩比都获得了较大改善,为小波变换下的图像压缩方法提供了新的思路。Aiming at disadvantage and insufficiency in primal EZW algorithm whose character of wavelet coefficient is not quantized according to frequency characteristic, a new improved algorithm is presented which includes signal-noise separation of wavelet coefficient , the valve disposition and different threshold quantization between low frequency and high frequency image information, in the case that make sure quality of rebuilt image, it proposes the judgment condition of stopping scanning, which saves scanning time more and can improve efficiency of image compression effectively during process of instant transmittal. The simulations show that the improved algorithm makes progress not only in PSNR of the same scanning times, but also in CR of approximate signal to noise ratio. Meanwhile, it provides new way of image compression under wavelet transform.

关 键 词：小波变换 图像压缩 EZW 信噪分离 闽值化处理 分阈值量化 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]