ENCODING DEVICE AND METHOD, RECORDING MEDIUM AND DECODING DEVICE AND METHOD

摘要

PURPOSE: To encode a second code string according to a second format whose encoding efficiency is higher than a first code string according to a first format so as to be silently reproduced by a reproducing device for reproducing the first code string of the first format. CONSTITUTION: A first codec dummy string generation part 132 generates a first codec dummy string in the first code string according to the first format by a first encoding method. A second codec encoding part 131 generates the second code string according to the second format different from the first format whose encoding efficiency is higher than the first code string. A code string generation part 133 generates a synthetic code string by burying the code string of second codec generated by the second codec encoding part 131 in a free area formed in the first code string based on the first codec dummy string generated by the first codec dummy string generation part 132.