| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a video signal switching device which suppresses deterioration in image quality to be a minimum period and to be a minimum degree even for a video signal with a different phase of a GOP coded by the moving picture coding experts group (MPEG) system and makes proper switching in the unit of pictures. SOLUTION: Sources 1, 2 are decoded by 1st and 2nd decoders 11, 12 and converted into base band video signals and delayed for 1 GOP period at 1st and 2nd delay circuits 13, 14. A 2nd switcher 15 selects a video signal of the source 1 into that of the source 2 and the selected signal is coded again by an encoder 16. In this case, a head of a GOP including a switched part is connected to an end of a GOP of the preceding source 1, and a signal coded by an intra-coded (I) picture in the first coding is coded again as an I picture and the phase is in matching with a phase of the source 2. A 3rd switcher 18 selects 1st, 3rd and 2nd delay circuits 13, 17, 14 in this order to switch the signal.</p> |
