A video output apparatus comprises: video data processor for processing plural pieces of video data of different types and outputting the resulting video data to a monitor; video processing delay detector for detecting whether processing for the plural pieces of video data performed by the video data processor is completed in real time when it is output to the monitor; and video data processing controller for controlling the video data processor so that the processing performed by the video data processor which is allocated for on line period is reduced when the video processing delay detector detects delay in processing.