Digital watermarking technology is to directly embed some identification information in the digital carrier or express it indirectly, and it does not affect the use value of the original carrier, and it is not easy to be detected and modified again. But can be identified and identified by the producer. Through the information hidden in the carrier, the purpose of confirming the content creator, purchaser, transmitting secret information or judging whether the carrier has been tampered can be achieved. Digital watermarking is an effective way to protect information security, realize anti-counterfeiting traceability, and copyright protection. It is an important branch and research direction in the field of information hiding technology.