To execute parallel encoding and to reduce code quantity in an MPEG encoder.

Plural processing units 1a to 1d are installed. Picture data in respective areas obtained by dividing a picture into four in the vertical direction are MPEG-encoded and the data of a slice layer are outputted. A detector 26 detects that all the sliced data are constituted of macro blocks that can be omitted. A controller 28 decides whether detection signals are outputted from a plurality of units of the adjacent areas or not. A pattern generator 30 outputs the single sliced data to a selector 22 based on a control signal from the controller 28 and substitutes plural pieces of slice data from the plurality of units for the single sliced data and reduces code quantity.