A data delivery device that switches picture data to be delivered so that pictures different in quality can be efficiently grasped without missing information of a high importance level is provided. The data delivery device receives picture data from multiple cameras through a network using a picture reception program. It determines whether or not to display each image frame of the picture data by accumulating the frequency of viewpoint switching or the importance level information of an image from each viewpoint by a picture selection program. In addition, it delivers a selected image frame through an interface by a picture transmission program. The display time for each frame is varied according to the importance level information of the image to enhance the viewability of an important frame.