Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Image Content Authentication Using Pinned Sine Transform | EURASIP Journal on Applied Signal Processing 2004 14 2174-2184 2004 Hindawi Publishing Corporation Image Content Authentication Using Pinned Sine Transform Anthony T. S. Ho School of Electrical Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Email etsho@ Xunzhan Zhu School of Electrical Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Email xzzhu@ Yong Liang Guan School of Electrical Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Email eylguan@ Received 23 October 2003 Revised 24 December 2003 Digital image content authentication addresses the problem of detecting any illegitimate modification on the content of images. To cope with this problem a novel semifragile watermarking scheme using the pinned sine transform PST is presented in this paper. The watermarking system can localize the portions of a watermarked image that have been tampered maliciously with high accuracy as well as approximately recover it. In particular the watermarking scheme is very sensitive to any texture alteration in the watermarked images. The interblock relationship introduced in the process of PST renders the watermarking scheme resistant to content cutting and pasting attacks. The watermark can still survive slight nonmalicious manipulations which is desirable in some practical applications such as legal tenders. Simulation results demonstrated that the probability of tamper detection of this authentication scheme is higher than 98 and it is less sensitive to legitimate image processing operations such as compression than that of the equivalent DCT scheme. Keywords and phrases semifragile watermarking content authentication pinned sine transform. 1. INTRODUCTION While digital media offer many distinct advantages over their analog counterparts the ease with which they can be edited and tampered makes the protection of their integrity
