• Title/Summary/Keyword: Multiple watermarks

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An Empirical Digital Image Watermarking using Frequency Properties of DWT (DWT의 주파수 특성을 이용한 실험적 디지털 영상 워터마킹)

  • Kang, I-Seul;Lee, Yong-Seok;Seob), Young-Ho;Kim, Dong-Wook
    • Journal of Broadcast Engineering
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    • v.22 no.3
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    • pp.295-312
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    • 2017
  • Digital video content is the most information-intensive and high-value content. Therefore, it is necessary to protect the intellectual property rights of these contents, and this paper also proposes a watermarking method of digital image for this purpose. The proposed method uses the frequency characteristics of 2-Dimensional Discrete Wavelet Transform (2D-DWT) for digital images and digital watermark on global data without using local or specific data of the image for watermark embedding. The method to insert digital watermark data uses a simple Quantization Index Modulation (QIM) and a multiple watermarking method that inserts the same watermark data in multiple. When extracting a watermark, multiple watermarks are extracted and the final watermark data is determined by a simple statistical method. This method is an empirical method for experimentally determining the parameters in the watermark embedding process. The proposed method performs experiments on various images against various attacks and shows the superiority of the proposed method by comparing the performance with the representative existing methods.

Scalable Fingerprinting Scheme based on Angular Decoding for LCCA Resilience (선형결합 공모공격에 강인한 각도해석 기반의 대용량 핑거프린팅)

  • Seol, Jae-Min;Kim, Seong-Whan
    • The KIPS Transactions:PartD
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    • v.15D no.5
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    • pp.713-720
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    • 2008
  • Fingerprinting scheme uses digital watermarks to trace originator of unauthorized or pirated copies, however, multiple users may collude and escape identification by creating an average or median of their individually watermarked copies. Previous research works are based on ACC (anti-collusion code) for identifying each user, however, ACC are shown to be resilient to average and median attacks, but not to LCCA and cannot support large number of users. In this paper, we propose a practical SACC (scalable anti-collusion code) scheme and its angular decoding strategy to support a large number of users from basic ACC (anti-collusion code) with LCCA (linear combination collusion attack) robustness. To make a scalable ACC, we designed a scalable extension of ACC codebook using a Gaussian distributed random variable, and embedded the resulting fingerprint using human visual system based watermarking scheme. We experimented with standard test images for colluder identification performance, and our scheme shows good performance over average and median attacks. Our angular decoding strategy shows performance gain over previous decoding scheme on LCCA colluder set identification among large population.