A video data distribution device 101 multicast or broadcast distribute moving picture data of the same video, the same encoding method, the same frame configuration but having different compression ratios in at least one different session according to the compression ratio or the video frame and the video block type and controls to notify session information or confidential information on the distribution data to a receiver according to the video quality permitted for the receiver to receive. A video data reception device 108 uses the notified session information or the confidential information so as to select encoded data from the normally received encoded data from at least one session, according to the video quality, and decode it.