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Báo cáo hóa học: " A Secure and Robust Object-Based Video Authentication System"

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: A Secure and Robust Object-Based Video Authentication System | EURASIP Journal on Applied Signal Processing 2004 14 2185-2200 2004 Hindawi Publishing Corporation A Secure and Robust Object-Based Video Authentication System Dajun He Institute for Infocomm Research I1 2R 21 Heng Mui Keng Terrace Singapore 119613 Email djhe@i2r.a-star.edu.sg Qibin Sun Institute for Infocomm Research I2R 21 Heng Mui Keng Terrace Singapore 119613 Email qibin@i2r.a-star.edu.sg Qi Tian Institute for Infocomm Research I2R 21 Heng Mui Keng Terrace Singapore 119613 Email tian@i2r.a-star.edu.sg Received 31 March 2003 Revised 6 December 2003 An object-based video authentication system which combines watermarking error correction coding ECC and digital signature techniques is presented for protecting the authenticity between video objects and their associated backgrounds. In this system a set of angular radial transformation ART coefficients is selected as the feature to represent the video object and the background respectively. ECC and cryptographic hashing are applied to those selected coefficients to generate the robust authentication watermark. This content-based semifragile watermark is then embedded into the objects frame by frame before MPEG4 coding. In watermark embedding and extraction groups of discrete Fourier transform DFT coefficients are randomly selected and their energy relationships are employed to hide and extract the watermark. The experimental results demonstrate that our system is robust to MPEG4 compression object segmentation errors and some common object-based video processing such as object translation rotation and scaling while securely preventing malicious object modifications. The proposed solution can be further incorporated into public key infrastructure PKI . Keywords and phrases watermark authentication error correction coding cryptographic hashing digital signature. 1. INTRODUCTION Nowadays the object-based MPEG4 standard is becoming growingly attractive to various applications in areas such as the Internet video editing .