Avoiding Hard Decisions in Adaptive Watermarking

In this paper, we describe the coupling of content adaptive watermark decoding and soft-decision forward error correction. We deduce three fundamental properties from adaptive watermarking methods switching between different embedding strengths. It is shown how a weighting process at the decoder can be used to build up an overall soft processing watermarking. No pre-distortion has to be used, and hence, the image quality is not degraded. In this conjunction, even adaptation techniques can be used where it is computational infeasible to project a pre-distortion back onto the host image. Experimental results indicate the improvement in bit error correction during watermark retrieval by a factor of 5. Without loss of security, performance or functionality our new technique can be integrated very easily into numerous watermarking applications.