Scanning mode and scanning mode switching arrangement

摘要

PURPOSE:To select the scanning system for an original video signal for noninterlace scanning or interlace scanning through the selection of the user. CONSTITUTION:The changeover device is made up of a RAM 1 storing a digital video signal Do for each color signal, a changeover circuit 3 whose scanning system is switched into interlace scanning or noninterlace scanning, a control section 4 reading the digital video signal from the RAM so that each scanning at each field scans the signal on the same horizontal scanning line depending on the selection of the changeover circuit, a D/A converter section 2 converting each digital video signal from the RAM into an analog signal, a synchronizing signal generating section generating a required synchronizing signal based on the selection of the changeover circuit 3 and an encoder 6 generating a composite video signal scanned on the same horizontal scanning for each field based on a signal from the D/A converter section and a signal from the synchronizing signal generating section or a decoded video signal relating to the interlace scanning.