Multiscreen video playing system dynamically generating scaled video, and related device

The invention provides a multiscreen video playing system dynamically generating scaled videos, and a related device. The system comprises a video playing device with a main display, portable communication devices with screens, and a multiscreen display control server. The multiscreen display control server transmits contents of a target video to the video playing device through a network, and the video playing device uses the main display to display the target video. In a process that the main display displays the target video, if the multiscreen display control server receives selection information corresponding to positions of local regions in the main display, the multiscreen display control server would dynamically generate scaled videos corresponding to images displayed in the local regions, and transmits contents of the scaled videos to the portable communication devices through the network, so that the portable communication devices can synchronously display the scaled videos using ...