Application of Error Control Coding for Multimedia Watermarking Technologies

Introduction

The watermarking has seen a sudden spurt in activities and interest after 1995. This is an era when internet started penetrating globe connectivity. This brought several worrying points including the rising concerns for copyright violations. Watermarking is seen as one of the potential means for preventing content flowing into the darknet. The watermarking has been included as technology into future DRM standards. The goal of the watermarking is to protect the copyright and prove ownership of digital content. There are several applications of watermarking apart from copyright protection. The Table 1 associates the type of watermark with their application and its desirable properties (Ingemar, 2008; Wenjun, 2006). It is presumed that readers are very clear about the basics of each one of these applications and hence they have been described very briefly in Table 1.

Summarizing issues that can be handled well by the ECC for watermarking are:

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  Providing reliable transmission of watermark through communication channel (Ingemar Cox, 2008)

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  Improving the payload of watermark by using codes operating near Shannon’s limit (A. Bastug, 2004).

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  Providing authentication and traitor tracing (Kaushal, 2004).

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  Providing the covert and secure communication (Kaushal, 2007).

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  Providing the unauthorized access protection (M. C. Davey, 2001).

However we have to always consider the fact when ECC is applied to watermarking is that, every type of code will perform error correction to its capacity only above minimum SNR level in communication channel. Below this level some of the codes instead of providing a “gain” will introduce a “loss” in terms of increased BER. This increased BER can also attributed be type of decoder and characteristics of errors. If we can keep check on channel input BER than we can use any type of ECC provided output BER drops.