PURPOSE: To arbitrarily select an expansion/reduction rate by detecting picture information between scanning lines of each expansion/reduction interval as the state linearly changing between respective lengthwise-direction expansion/reduction information to obtain imaginary picture information and scanning this information to obtain expanded/reduced reproduced picture information and reproducing an expanded/reduced picture in accordance with these expanded/reduced reproduced picture information.

CONSTITUTION: An imaginary picture information generating means 3 arranges respective lengthwise-direction expansion/reduction information, which are obtained by a lengthwise- direction expansion/reduction information generating means 2, at expansion/reduction intervals obtained by multiplying intervals of scanning lines by the expansion/reduction rate. Picture information between scanning lines of each expansion/reduction interval is detected as the state linearly changing between respective lengthwise-direction expansion/reduction information to obtain imaginary picture information. An expanded/reduced reproduced picture generating means 4 obtains imaginary picture information as expanded/reduced reproduced picture information along plural scanning lines arranged at prescribed intervals, and this information is used for following reproducing of an expanded/reduced picture. Thus, the picture is obtained which is expanded/reduced by arbitrary expansion/reduction rates in the lengthwise direction and the interval direction of scanning lines respectively.