2003-348324 is referenced by 17 patents.
PROBLEM TO BE SOLVED: To reduce deterioration as much as possible when performing multiple digital watermarking. SOLUTION: A second sub information adding part 40 in a multiple digital watermarking apparatus 1, while referring to contents of a reference target such as source contents in addition to contents of an embedding target stored in a contents storage part 22, generates contents candidates added with sub information, and a candidate is selected from the candidates while using a function for evaluating deterioration from the contents of the reference target so that the little deteriorated candidate is selected. Thereby, the more accurate and objective selection of the candidate is made possible than the selection on the basis of the evaluation of a user through viewing. Further, the apparatus has a first sub information adding part 30 for generating candidates without referring to the contents and a part 50 for judging the number of times of sub information addition for monitoring how many times embedding processing is carried out so that complicated sub information adding processing is made possible when the first or second sub information adding means are combined by the arbitrary number of times.