基于纠错编码和扩频调制的彩色图像水印算法

摘要

In this paper, an algorithm is presented with error-correcting codes and code division multiple access (CDMA) for color image digital watermarking. Arnold scrambling, error correction coding and spread spectrum modulation are operated on the secret information. Extract the green component of the host color image, Discrete Cosine Transform (DCT) is done on the components, the preprocessing watermark will be embedded into the part of the IF area. In the stage of watermark extraction, the image of the green component is operated with DCT, followed by the IF part of the watermark extraction, the extracted values and key obtained from the Gold sequence set to do the correlation, Inverse Arnold transform is required after the error correction decoding, and it can get the useful watermark sequence. Theoretical analysis and experimental results show that the algorithm can resist cut and local malicious tampering attacks, also has good noise robustness, and its overall performance is better than the existing similar watermarking algorithm.%提出一种基于纠错编码和码分多址(CDMA)的彩色图像水印算法,先后将秘密信息进行Arnold置乱,纠错编码,扩频调制.提取宿主图像的绿色分量,对其进行离散余弦变换,将预处理的水印嵌入到变换后的部分中频区域.水印提取部分,首先对待测图像的绿色分量做离散余弦变换,其次提取中频部分的水印信息,将提取的值和由密钥得到的Gold序列集做互相关进行解扩,最后纠错译码并进行Arnold反变换即得到需要的水印序列.理论分析和实验结果表明,该算法不仅能有效抵抗剪切攻击和局部恶意篡改,对噪声亦具有很好的稳健性,其整体性能优于现有同类水印算法.