Patent ID: 7026960

Claim:
An apparatus for encoding differential pulse code modulated (DPCMed) differential data of key data, which are information on the locations of key frames on a time axis, the apparatus comprising: a divide-and-divide (DND) operator which performs on input differential data a predetermined number of times a DND operation, in which a divide operation is performed on the input differential data so as to divide differential data belonging to a positive number region into halves and so as to convert one half of the differential data belonging to an upper range into negative values, and either a divide-up operation or a divide-down operation is selectively performed on the results of the divide operation depending on a range of the results of the divide operation so as to reduce a range of differential data belonging to a negative number region or the positive number region, respectively; a shift-up operator which performs a shift-up operation on the results of the DND operation so as to transfer the differential data having been through the DND operation to either the positive or negative number region; a differential data selector which selectively outputs either the differential data having been through the DND operation or the differential data having been through the shift-up operation; and an entropy encoder which entropy-encodes the differential data selected by the differential data selector.