VIDEO DECODER

A video decoder including: an input module configured to receive a video stream that is coded based on macroblocks; a frame determination module configured to determine whether or not a decoding subject image in the video stream that is input to the input module is a non-reference frame image that is not referred to when decoding another image; a slice analyzing module configured to determine, for each slice being configured by arranging the macroblocks, whether or not skip macroblocks each of which has no coding information of its own exist in a predetermined number or more when the frame determination module determines that the decoding subject image is a non-reference frame image; and a slice editing module configured to set, as skip macroblocks, all macroblocks in a slice for which the slice analyzing module determines that skip macroblocks exist in the predetermined number or more.