"Digital watermarking" refers to the application of watermarking techniques in digital media, including digitized images (such as JPEG), audio (such as MP3), and video (such as DVD). In order to prevent these digital media from being illegally downloaded and used on the internet, we can embed some representative symbols (such as registered trademarks or personal portraits) into these digital media using related techniques to prove their legal owner, and thus protect intellectual property rights. When someone illegally downloads and uses these digital media that have already been embedded with "digital watermarks," we can extract the "digital watermarks" from the digital media using related techniques to prove who the legal owner is, in order to protect the intellectual property rights of the work.
Visible examples of digital watermarks
Schematic diagram of the embedding and extraction process of digital watermarks.