A device for previewing a video includes a memory device configured to store instructions, and one or more processors configured to execute the instructions to receive a video captured by a camera and analyze the video. The one or more processors are also configured to detect a special event from the analysis of the video. The special event includes at least one of an object, a moving object, or a sound detected in the video. The one or more processors are further configured to extract, from the video, at least one of a video preview frame or audio segment corresponding to the special event, and generate a preview video including the at least one of the video preview frame or audio segment corresponding to the special event.