CAJ | 학술논문

半脆弱水印因为在多媒体内容认证方面的重要作用而受到人们密切的关注.为了能够区分恶意篡改与偶然操作,半脆弱水印要求对常用的内容保护图像操作应具有一定的鲁棒性.由于JPEG压缩在图像处理的广泛应用,对恶意篡改攻击具有较高的检测能力,半脆弱水印研究的一个重要问题是提高抗JPEG压缩性能.该算法首先图像小波高频子带系数LH2,HL2分别进行分块,然后算出分别每块的系数的能量值,根据能量系数之间的大小关系嵌入水印信息.实验测试表明,所提出的算法不会影响图像的主客观质量,有很好的抗 JPEG 压缩性能,而且可嵌入的水印信息量大,并且能够准确确定恶意攻击的位置.
반취약수인인위재다매체내용인증방면적중요작용이수도인문밀절적관주.위료능구구분악의찬개여우연조작,반취약수인요구대상용적내용보호도상조작응구유일정적로봉성.유우JPEG압축재도상처리적엄범응용,대악의찬개공격구유교고적검측능력,반취약수인연구적일개중요문제시제고항JPEG압축성능.해산법수선도상소파고빈자대계수LH2,HL2분별진행분괴,연후산출분별매괴적계수적능량치,근거능량계수지간적대소관계감입수인신식.실험측시표명,소제출적산법불회영향도상적주객관질량,유흔호적항 JPEG 압축성능,이차가감입적수인신식량대,병차능구준학학정악의공격적위치.
Semi-Fragile watermark has attracted attention due to its important role in content authentication for multimedia. In order to differentiate incidental attacks and malicious attacks, semi-fragile watermark should be robust against content-protection image processing. Semi-fragile watermark resisting to JPEG compression while maintaining high detection ability to tamper has been the emphasis in the area. This algorithm of image wavelet coefficient LH2 and HL2 was blocked and computed each of block coefficient energy based on the relative energy relations embedded watermark. Simulation experiments prove that it will not degrade the objective and subjective quality of original images, the good robustness to JPEG and the larger amount of embedded information. What’s more, it can ascertain the position of vicious attack exactly.