Victor Company of Japan, Limited

Hiroyuki Hattori

Akiyoshi Morita

A composite video signal is processed for superimposing characters on an image represented by the video signal, where a memory (33) and a character generator (31) used for superimposing the characters at an appropriate position are both controlled by a control unit having an odd-field detector (38), a shift pulse generator (44), a rewrite pulse generator (45) and a window pulse generator (54). The odd-field detector (38) produces an odd-field pulse each time a coming odd field is detected, and the number of the odd-field pulses is counted so as to be compared with the number of H sync pulses of the composite video signal. The number of H sync pulses fed to the character generator (31) is reduced by the number of detected odd-field pulses thereby smoothly naturally moving or scrolling displayed characters vertically starting from an odd field. A given number of character lines are displayed simultaneously with remaining lines being concealed by an electronic window (a) formed in response to the window pulse generator (54), and character data is rewritten, by the rewrite pulse generator (45) responsive to the shift pulse generator (44), such that data of character lines pushed out of the window (a) is erased and data of a new line is added.

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Kawasaki, Japan

Hiroyuki Hattori