To provide a first memory for storing an odd field data, a second memory for
storing
an even field data acquired in an NTSC system, a third memory for storing the same
video data stored in the first and second memories, and a TV standard conversion
circuit. For the data in a period for which a writing of a next data overtakes
reading of the data from the first memory or the second memory, a writing into
the third memory is inhibited, and the data is read from the third memory, whereby
the signal of the NTSC system is converted into the signal of a PAL system. In
this manner, an excellent video is displayed on a PAL monitor without any the bar noise.