一种用于智能卡的人像信息压缩算法

为了提高现今被广泛使用的智能卡的安全性，本文提出了在智能卡中加入持卡人人像信息的方案，并且针对方案中由于智能卡容量的限制而引起的彩色人像信息的压缩问题提出了一种基于人像特征的分级压缩算法。该算法把无损压缩与有损压缩统一在小波变换的框架下，首先在图像中检测出人脸区域，然后对该区域采用无损压缩或低压缩比有损压缩，而对其它区域则采用高压缩比有损压缩。实验证明，该算法在压缩比和重建图像质量上取得了较好的效果。

A COMPRESSION ALGORITHM FOR PERSONAL IMAGE INFORMATION USED IN SMART CARD

To improve the security of smart card,which is widely used in modern society,a novel idea of inserting personal image information is proposed in this paper.A classifying compression algorithm based on facial feature is proposed to solve the key problem caused by memory limitation in Smart Card.The algorithm uniforms the lossy and lossless compression under wavelet framework,detecting the facial region at first and using lossless compression or lossy compression with low compression ratio to this region but using lossy compression with high compression ratio to other regions.It is proved from the experiments that higher compression ratio and better image quality can be acquired by using this algorithm.