| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a multicast broadcasting system which distributes multicast broadcasting. <P>SOLUTION: The multicast broadcasting system includes: a video distribution server 2 capable of distributing high-definition video image information and low-definition video image information by every channel; and a video terminal 1 having a receiving function of receiving each piece of video image information by participating in a multicast group of the high-definition video image information of a desired channel and a multicast group of the low-definition video image information of a channel adjacent to the channel, wherein the video terminal 1 switches, when the adjacent channel is selected during broadcasting, a video image under broadcasting to the preliminarily received video image of the low-definition video image information of the adjacent channel, thereafter receives pieces of video image information of the adjacent channel and a channel adjacent thereto by the receiving function, and furthermore breaks away from a multicast group of video image information which becomes unnecessary after switching the video image of the low-definition video image information to the video image of the high-definition video image information received by the receiving function. <P>COPYRIGHT: (C)2010,JPO&INPIT |
