A framework for the design of good watermark identification codes

The fundamental difference between the data-hiding and watermark signature verification problems was highlighted in a 2001 paper by Steinberg and Merhav. In data hiding, the maximum number of messages that can be reliably decoded is essentially 2 , where n is the host sequence length and C is the data-hiding capacity. A dramatically different result is obtained for signature verification: in principle one can discriminate between a doubly exponential number of signatures: 2 nC ′ , where C ′ is the identification capacity. This paper proposes a practical design of codes for the latter application and compares the results with current designs in the literature.