Research On Image Watermarking Technique Based On BTC

Nowadays, as an effective means of copyright protection digital watermarkingtechnology has obtained widespread concern and rapid development. Mediatransferred in Actual communication applications are mainly compressed carriers.But existing transformation watermarking algorithms has high computation cost,and is not effective to real-time communication applications via Internet. BlockTruncation Coding is a very simple and fast image code scheme. This thesisfocused on BTC domain image watermarking technique by employing image BTCcharacteristics. The main contributions of this thesis are as following.BTC image fragile watermarking algorithm. A digital image fragilewatermarking technique based on BTC domain is presented. The watermark isembedded into the host image according to the odevity of the reconstruction levelsof the BTC quantizer. The watermark extraction need not resort to the originalimage, and the algorithm has low computation cost, and can be applied to digitalimage authentication in real-time environment. Experimental results prove thatproposed algorithm have good invisibility with the PSNR value above45dB. Thescheme achieves high performance in tampering detection and location.Robust image watermarking algorithm based on BTC and VSS (Visual SecretSharing). A novel robust image watermarking technique is presented by combiningBTC and secret sharing. The feature share of the original image which isconstructed by BTC is combined with the watermark to generate the private share.In watermark extraction, the watermark can be retrieved by XOR operationbetween the private share and the feature from the suspected image. The privateshare is dependent of the feature share, and it is possible to register multiplewatermarks for a single host image the scheme, and the robustness of the featureshare ensure the watermark robustness. Moreover, this scheme does not alter thehost image when the private share is generated. Experimental results show highrobustness of proposed algorithm against common signal processing attacks.This thesis provided new methodology and key techniques for BTC basedimage watermarking algorithms. Research achievements in the paper will offersecure guard for secure image communication and image authentication inreal-time applications via the Internet, and be help to promote the healthy and orderly development of digital media industry.