Abstract: It is point out that the digital watermarking system is a proof system through researching the watermarking system model.Define the concepts of watermark embedding point and watermark detection point and give the condition of availability and fair of the watermarking system must be met.A novel watermarking scheme based on the structure of correcting code is proposed,and analysis the scheme in theory and get the result that this scheme is robust for some attack and signal processing.Finally,it is pointed out that this scheme can be translate to secure public watermark detecting system based on the extended TPM technology.