METHOD FOR INSERTING SECRET DATA INTO IMAGE DATA, METHOD FOR DETECTING SECRET DATA AND METHOD FOR DISPLAYING IMAGE DATA WITH SECRET DATA INSERTED

摘要

PPROBLEM TO BE SOLVED: To provide an image data displaying method for simultaneously displaying a plurality of pieces of information by using a secret data inserting method for efficiently inserting secret data into compressed image data, a secret data detecting method and the secret data. PSOLUTION: A partial decoding part 14 partially decodes compressed image data. A quantization transformation coefficient (a) obtained from partial decoding 14 is inputted to a secret data inserting part 11, and the secret data 12 is also inserted into the secret data inserting part 11. The secret data inserting part 11 inserts the secret data into the quantization transformation coefficient (a). A partial encoding part 15 partially encodes the quantization transformation coefficient b after the secret data insertion and outputs the quantization transformation coefficient and secret data inserted compressed image data. The secret data inserted compressed image data can be made to be, for example, media data as the secret data, and the medial data can be simultaneously displayed with image data. PCOPYRIGHT: (C)2005,JPO&NCIPI