PURPOSE: To improve the encoding efficiency by using the disk medium where data divided into groups by a certain number of track is arranged and byencoding data in the range having the data volume, which is unequivocally determined in accordance with the area on this disk medium, as the upper limit.

CONSTITUTION: Video data inputted to a video data encoding circuit 5 is encoded and is inputted to a selective output circuit 10. The control like roughening of the step of quantization is performed in a rate control circuit 8a based on the result, which is obtained by detecting the data volume of output data of the circuit 5 by a data detecting circuit 8b, and control data inputted to a recording zone detecting and discriminating circuit 4. In the same manner, audio data inputted to an audio data encoding circuit 6 is encoded and 18 inputted to the circuit 10. Extended data like a sub-code is encoded by an extended data encoding circuit 7 and is inputted to the circuit 10-The circuit 10 collectively outputs the outputs of circuits 4, 5, 6, and 7. A low rate control precision can be set in circuits 8a and 9a, and the encoding effciency is improved.