METHOD FOR AUTHENTICATING AN ILLUSTRATION

The invention relates to a method for authenticating an illustration, comprising - encoding a message in the form of a two-dimensional barcode comprising blocks, each block coding a fragment of said message and comprising a set of coding sub-blocks, each sub-block comprising a set of binary elements. It is essentially characterised in that the encoding comprises prior steps consisting in: - defining or identifying a set of noteworthy points in the illustration, - calculating a set of attributes depending on certain at least of the noteworthy points, - selecting, among the calculated attributes, at least one attribute allowing a digital fingerprint to be defined, - optionally compressing said digital fingerprint, - optionally signing said digital fingerprint by means of a cryptographic signature, and - recording in the message one among: - a set of at least one attribute, - the digital fingerprint, - the compressed digital fingerprint, and - the signed and optionally compressed digital fingerprint.