Patent ID: 9104845
Filing Date: 2015-08-11
Classification: G06F

Abstract:
1. A digital content management system comprising: a server computer or a personal computer, a memory, a hard disk and a communication device, wherein when the server computer or the personal computer reads a program loaded onto the memory for the purpose of implementing: a digital watermark embedder which generates embedding information uniquely determined from identification information for tracking use, specifies an embedding location uniquely determined based on the generated embedding information, and embeds a digital watermark based on the generated embedding information into a digital content to be managed, based on the specified embedding location; a digital watermark detector which generates tracking information uniquely determined from identification information for verification use, specifies a search location uniquely determined based on the generated tracking information, and detects said digital watermark based on the generated tracking information in a digital content to be verified, based on the specified search location; a verifier which verifies said identification information for verification use, which is used for verifying said digital content to be verified, in which, said digital watermark is detected; wherein said digital watermark embedder generates said embedding information uniquely determined from said identification information for tracking use, by encryption using a secret key, and embeds the digital watermark into said digital content to be managed, based on the generated embedding information, said digital watermark detector generates said tracking information uniquely determined from said identification information for verification use, by encryption using the same secret key used in said digital watermark embedder, and detects said digital watermark in said digital content to be verified, based on the generated tracking information, and said verifier further comprises: a decoder which decodes said tracking information generated by encryption by said digital watermark detector using a public key which is a pair to said secret key used in said digital watermark detector; and a collator which collates information obtained by decoding by said decoder, with said identification information for verification use.