摘要
提出一种基于多小波变换和SPIHT编码的可恢复半脆弱数字水印算法。为实现篡改恢复,算法将原始图像的高压缩比SPIHT编码添加伪随机序列后置乱、分块生成水印,而后嵌入图像多小波变换的低频分量中,实现自嵌入。利用图像半色调化后的半脆弱性进行篡改定位;通过提取并解压出的自嵌入图像来实现篡改区的近似恢复。仿真实验表明,算法对于篡改定位精度较高,并可实现篡改区的近似恢复。同时,由于算法采用密钥来控制水印的嵌入位置,从而保证了水印的安全,使算法有较强的实用性。
A recoverable semi-fragile watermarking scheme based on multiwavelet and SPIHT coding is proposed. The algorithm employs a compressed image by a modified SPIHT algorithm as watermark and embeds it in the multiwavelet domain through quantization index modulation. While the watermarked image is tampered unautborizedly, compare the halftoned tampered image and the halftoned decompressing image to localize the tampered areas automatically without initial hi-watermark. Experimental results show that the proposed scheme is effective for smaller area tamper localization and recovery.
出处
《计算机技术与发展》
2011年第5期147-150,154,共5页
Computer Technology and Development
基金
河北省科技计划基金项目(05213579)
