Abstract: In order to effectively determine 3D video from the video information, improve the user convenience while avoiding the risk of erroneous determination due to unconditional 3D switching, and reduce process load due to unconditional determination of the video, a 3D determination method based on video information is performed by means of a plurality of resources such as the correlation information of the video. At this time, it is determined whether the video signal is 3D video or 2D video according to the time and conditions set for the determination. Then, the video output is switched between 2D video and 3D video based on the determination result. Or a message is displayed to check if the user enables or disables 3D switching before the video is switched. Or, the conditions for the video determination are limited.