Bit error rate in digital watermarking systems using spread spectrum techniques

In spread spectrum (SS)-based digital watermarking systems, watermark information is spread by a pseudorandom code and added to the original information signal. On the other hand, we have proposed another watermarking system having one watermark channel and several image transmission channels. Information data is modulated by SS codes with variable code length according to its significance. This paper inspects bit error rate of such a watermarking system for both watermark channel and image transmission channels.