Patent ID: 6131162
Filing Date: 2000-10-10
Classification: G06F,G06T,H04L,H04N

Abstract:
An embed-in-content information processing method for embedding information on k (k is an integer equal to or larger than 2) content-handling persons using an electronic computer, the method comprising the steps of:creating a digital signature of a first content-handling person by encrypting a hash value using a private key in accordance with a public key cipher system of the first content-handling person, the hash value being created by evaluating the content with a first hash function;sequentially repeating digital signature creation for a second person to a k-th content-handling person to create the digital signatures of the content-handling persons; andembedding the digital signature of the k-th content-handling person into the content such that the digital signature of the k-th content-handling person cannot be separated from the content without using a predetermined rule, the digital signature of the k-th content-handling person being obtained by performing said digital signature creation for the k-th content-handling person, wherein, during said digital signature creation processing for an i-th content-handling person (i is an integer between 2 and k), a value dependent on the digital signature of the (i-1)th content-handling person is encrypted using the private key of the i-th content-handling person to generate the digital signature of the (i-)th content-handling person.