Moving pictures are reproduced from a stored moving-picture signal and
output at a set reproduction speed. The stored moving-picture signal is
reproduced in accordance with the set reproduction speed to obtain first
interlaced pictures. The first interlaced pictures are converted to
obtain first progressive pictures. Moving pictures to be displayed are
selected from the first progressive pictures per frame in accordance with
the set reproduction speed to obtain second progressive pictures.
Scanning lines of the second progressive pictures are decimated so that
the number of remaining scanning lines of the second progressive pictures
after decimation is equal to the number of scanning lines of interlaced
pictures to be displayed, thus outputting second interlaced pictures. The
first interlaced pictures are output when the set reproduction speed is
the first reproduction speed whereas the second interlaced pictures are
output when the set reproduction speed is the second reproduction speed.