VIDEO PRODUCING SWITCHER

PURPOSE:To easily obtain an arbitrary pattern used for a masking signal to eliminate an unrequired signal or the synthesis of picture planes, by providing a frame memory to store a pattern generated from a wipe pattern generator, a feedback circuit to connect the output and the input of the frame memory, and an OR circuit. CONSTITUTION:The required number of wipe pattern generators is suppressed at the minimum sets by arranging the frame memory 4 at a part requiring a static pattern and by a method to store a desired pattern respectively. In an actual using method, the output of the wipe pattern generator is distributed by arranging the frame memory 4 at every place of a video producing switcher requiring a wipe pattern, and the frame memory 4 outputs a fixed pattern, or control whether the pattern supplied by the wipe pattern generator should be passed as it is, is performed by performing write control on the frame memory 4.