CAJ | 학술논문

相比数字图像水印，在采用半脆弱水印技术进行视频内容认证时，由于嵌入水印量比较大，对算法的运行速度提出了更高的要求。本文改进了基于亮度分块的数字视频空域半脆弱水印算法，能保持水印的鲁棒性不变，且提高了水印的嵌入速度。基于相邻亮度分块的平均值大小关系在非恶意操作前后保持不变的特点，本文运用改进算法生成水印序列，并在时域上将水印嵌入DCT系数中。该算法具有不涉及具体编码格式，无需原视频参与认证，快速定位篡改区域的优点。仿真实验结果表明水印嵌入达到了18.37MB/s的速度，对画质影响不可见，实验结果同时证明了算法具有良好的实时性。
상비수자도상수인，재채용반취약수인기술진행시빈내용인증시，유우감입수인량비교대，대산법적운행속도제출료경고적요구。본문개진료기우량도분괴적수자시빈공역반취약수인산법，능보지수인적로봉성불변，차제고료수인적감입속도。기우상린량도분괴적평균치대소관계재비악의조작전후보지불변적특점，본문운용개진산법생성수인서렬，병재시역상장수인감입DCT계수중。해산법구유불섭급구체편마격식，무수원시빈삼여인증，쾌속정위찬개구역적우점。방진실험결과표명수인감입체도료18.37MB/s적속도，대화질영향불가견，실험결과동시증명료산법구유량호적실시성。
Because of the large number of watermark embedding,using semi-fragile video water-marking for content authentication demands a higher level of operating speed compared with digital image water-marking. In this paper,we improve the spatial semi-fragile watermarking algorithm which based on lumi-nance blocks,and the algorithm can keep a better robustness as well as embedding speed. By using the optimized algorithm,which is based on the feature that two adjacent luminance blocks has a constant ener-gy relationship in the non-malicious situation,the watermarking sequences are produced and embedded in-to DCT coefficient. This algorithm has its advantages,such as,does not involve specific encoding format, does not need original video for authentication,and even can localize the tampered region quickly. The simulation experimental results demonstrate the embedding speed reach 18. 37MB/s,and with invisible quality loss,meanwhile,it shows that the algorithm has good realtime response.