a method for watermark detection based on error control codes and a method for determining threshold for watermark detection are proposed.The basic idea is that watermark be encode with ECC
and then the extracted watermark subtract the feedback one
finally compare the subtractive result with the threshold selected for watermark detection.Thus the existence or not of watermark can be detected.The Turbo code of error control codes is used in the experiment.The simulation results using an algorithm based on DWT show that the errors of watermark image presented during the transportation is reduced greatly and the robustness of it is enhanced with the method proposed.