A New Image Copyright Protection Algorithm Using Digital Signature of Trading Message and Bar Code Watermark
Ji-Hong Chang, Long-Wen Chang · 2003
A new digital watermarking algorithm for images with bar code and digital signature is proposed. Digital signature is used to prevent a buyer from distributing unauthorized image copies and is also used to prevent a seller from forging the sale transaction of image copies without a buyer. We encode both the buyer’s and the seller’s signature into a bar-code and embed the bar-code into the image for trading. Both signatures are used to verify the integrity of the trading messages. Also, a cryptography technique is used not only for choosing embedded positions but also for protecting the trading messages. The signed trading message that contains the buyer’s name, the seller’s name, the object name, the trading price and the trading date is embedded in four images to test our proposed copyright protection algorithm. Our simulation shows that the proposed algorithm gets satisfactory results for various attacks.