METHOD OF CREATING AND CHECKING ELECTRONIC IMAGE AUTHENTICATED BY DIGITAL WATERMARK Russian patent published in 2012 - IPC G06K9/00 

FIELD: information technology.

SUBSTANCE: invention can be used to protect authenticity of electronic images which are compressed using electronic image compression algorithms and transmitted over public transmission channels, in which a violator can impose false electronic images onto a user. The method comprises steps for: dividing an electronic image into pixel blocks; performing three-dimensional discrete cosine transform over each block; forming an electronic image block authenticator using an authentication key; a digital watermark for an electronic image block is calculated by dividing the authenticator of that block into several parts and selecting Huffman code binary sequences corresponding to parts of the authenticator of that block as parts of the digital watermark; embedding parts of the digital watermark into the same block of the electronic image using an embedding key binary sequence; sending to a recipient an electronic image which is authenticated by a digital watermark and authenticating the received electronic image using an authentication key binary sequence and an embedding key binary sequence.

EFFECT: high security of electronic images authenticated by a digital watermark from deliberate altering of the content of the images by a violator.

4 cl, 8 dwg