ADDITIONAL INFORMATION INSERTING DEVICE AND ADDITIONAL INFORMATION EXTRACTING DEVICE, AND ADDITIONAL INFORMATION INSERTING METHOD AND ADDITIONAL INFORMATION EXTRACTING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an additional-information-inserting device that can insert additional information including user data into contents data without increasing the size of the contents data. SOLUTION: This additional-information-inserting device is provided with an empty area generating part 113 that generates an empty area by reducing a first number of bits of image codes in the contents data 151A to a second number of bits less than the first number of bits, and an additional information inserting part 114 that inserts the additional information into the empty area. The empty area generating means reduces the number of bits of the image codes for every coded block of moving images represented by image codes. According to an embodiment, the empty area generating means generates the empty area belonging to a slice for every slice, which is an area formed by dividing the space of the moving images represented by the image codes, containing a plurality of coded blocks of the moving images represented by the image codes. The additional information inserting means inserts the additional information into every empty area belonging to each slice.