Description: 本程序基于小波变换的三级分解及重构相关程序，有利于对小波变换在图像压缩中的应用的学习与了解。-procedures based on the wavelet transform three decomposition and reconstruction associated procedures, it is beneficial for wavelet transform in image compression applications of learning and understanding. Platform: |
Size: 2048 |
Author:姚永辉 |
Hits:
Description: 盲水印提取时不需要参考原始载体图像,在信息隐藏、版权保护等方面具有更广泛的应用前景。提出的盲水印算法在分块离散余弦变换(DCT)和离散小波变换(DWT)的基础上,利用关系双方DCT系数和DWT系数在受到攻击时具有相同变化趋势的特点,采用关系嵌入和量化嵌入的自适应选择嵌入策略,较大幅度地提高了盲水印提取的鲁棒性。同时在量化嵌入中采用抖动调制,实现了水印透明性和鲁棒性调节的便捷性。大量仿真实验结果表明该算法对噪声干扰、低通滤波、JPEG压缩、对比度增强等攻击有很好的鲁棒性和透明性。关键词 数字水印盲水印关系嵌入量化嵌入离散余弦变换离散小波变换
按这篇文章的算法，自己编的matlab,没有攻击时水印提取率为1，加水印后图像PSNR有45+，。有攻击后提取率也有0.9+。-Blind watermark extraction can be fulfilled without referring to the original host image. Therefore it hasmuch
prospective applications in the fields of information hiding and copyright protection. Based on blocking Discrete Cosine
Transform (DCT) and blocking DiscreteWaveletTransform (DWT), the proposed blind watermarking algorithm uses an
embedding strategy of adaptively selecting either relationship embedding or quantization embedding. The relationship em-
bedding comes from the observation thatboth themagnitudes of coefficients concerned in the relationship usually have thesame change trend when the image is attacked. This strategy remarkably improves the robustness ofwatermark extraction.In addition, dithermodulation is used in quantization embedding, bywhich the tradeoff between transparency and robus-tness ofwatermarking can be easily adjusted. Simulation results show that the algorithm is fairly robust against the attacks such as noise, filtering, compression, and contrast Platform: |
Size: 758784 |
Author:CXF |
Hits:
Search - DWT Based Image compression in matlab