Application Of Communications Technologies In Robust Digital Watermarking

As one of the approaches to protect multimedia copyright, digital watermarkinghas attracted great concern. Robustness is one of the important requirements of digitalwatermarking. To improve robustness, people regard watermark channel as commoncommunications channel, and introduce communications theories into watermarking soas to lower watermark detection bit error rate(BER).However, there exists important di?erence between watermark channel and commoncommunications channel, which results in some problems in the application of communi-cations theory. Our main contributions are as follows:(1) Having investigated the limitation of the application of communications methods inwatermarking. Firstly, using quantization-based watermark embedding, we derivedthe expression of PSNR, and showed the trade-o? between payload and embeddingstrength. Then, we discussed the e?ectiveness of error correction codes (ECC), andcompared the performance of schemes using di?erent types of ECC by experiments.Our investigation shows that ECC cannot e?ectively improve the robustness ofwatermarking against a vast majority of various attacks except for cropping andjitter attacks.