A picture target amount-of-code calculating unit calculates a target amount of
codes for each picture type that corresponds to an encoding rate that has been
determined by an audio/video encoding rate determining unit. An amount-of-code
controlling unit controls the quantizing scale of a quantizing unit so as to make
the target amount of codes for each picture type match with a total amount of codes
of a unit as a whole. A unit address calculating unit calculates the addresses
used when a search is made, as navigation data, on the basis of the target amount
of codes for each picture type and the encoding rate. A unifying unit makes a construction
of the unit while, on the other hand, a navigation data producing unit depicts
navigation data at a foremost position of the unit.
