A SUBPICTURE IMAGE SIGNAL VERTICAL COMPRESSION CIRCUIT

摘要

A SUBPICTURE IMAGE SIGNAL VERTICAL COMPRESSION CIRCUIT FOR VERTICALLY COMPRESSING SUBPICTURES OPERATING AT RESPECTIVE SYNCHRONOUS TIMINGS DIFFERENT FROM THAT OF THE MAIN PICTURE WHEN A PLURALITY OF IMAGE SIGNALS HAVING RESPECTIVELY DIFFERENT SYNCHRONIZATIONS ARE DISPLAYED ON AN IMAGE DISPLAY DEVICE. DEPENDINGON WHETHER THE FIELD POLARITIES OF MAIN AND SUB PICTURES ARE THE SAME OR NOT, THE SUBPICTURE IMAGE SIGNAL VERTICAL COMPRESSION CIRCUIT GENERATES SUITABLE OFFSETS FOR THE FIRST AND THE SECOND FIELDS TO ADJUST THE PHASES AND PREVENT THE INVERSION OF THE SCAN ORDER IN THE VERTICAL DIRECTION, AT THE FIRST FIELD AND THE SECOND FIELD OFSUBPICTURE SIGNAL, AFTER THE PHASE ADJUSTMENT TO OBTAIN A SUBPICTURE IMAGE WITH NATURAL MOTION IN THE VERTICAL DIRECTION. (FIGURE 1)