| 摘要 |
PROBLEM TO BE SOLVED: To prevent the communication band of a transmission line from being wasted when image data transmitted from an image source through the transmission line are displayed on a display device. SOLUTION: When image data are transmitted from an Internet terminal 10, a navigation device 20, a TV tuner 30 or the like, to a display device 50, the image data corresponding to the picture size of display on the display device 50 are generated and transmitted. The navigation device 20 as a subject which supplies, for example, a navigation picture as a main picture transmits the image data of the size of one picture (lateral 640 dots by longitudinal 480 dots) and the Internet terminal 10 as the subject which supplies an Internet picture as a subpicture only transmits the image data of the size of a 0.5 picture (lateral 320 dots by longitudinal 240 dots). Consequently, only the communication band for a 1.5 picture in total is occupied and the communication band of a multiplex communication path 40 can be prevented from being wasted. |
