Patent ID: 7603720
Filing Date: 2009-10-13
Classification: G06F,H04H,H04L,H04N

Abstract:
1. A method for creating non-repudiation watermarking protection based on public and private keys, comprising: (a) distributing media content front a content provider to a particular distribution entity selected from a plurality of distribution entities, for subsequent distribution to one or more displaying entities separate from the content provider and distribution entities; (b) providing a nonce from the content provider to the particular distribution entity; (c) generating a public and private key pair for the watermark at the particular distribution entity, wherein the private key of the pair is used by the particular distribution entity to encrypt the nonce as a watermark key; (d) generating a watermarked copy of the media content at the particular distribution entity using the watermark key; (e) transmitting the public key of the pair from the particular distribution entity only to the content provider, wherein the public key is not shared with any other entity; and (f) detecting the watermark in the watermarked media content at the content provider by obtaining the watermarked copy of the media content, extracting the watermark key therefrom, and decrypting the nonce from the extracted watermark key using the public key of the pair; (g) wherein the media content watermarked by the particular distribution entity is undeniably recognizable by the content provider as originating with that particular distribution entity from among all of the plurality of distribution entities, thereby allowing the content provider to place a high degree of trust in an identification of the particular distribution entity by means of the watermark.