A decoding system decodes a video stream, which is encoded video information. The decoding system includes an attribute information acquirer that acquires first attribute information, indicating whether a dynamic range of luminance of the video stream is a first dynamic range or a second dynamic range that is wider than the first dynamic range, and a decoder that acquires the video steam and generates decoded video information. The decoding system also includes an outputter that, in a case where the first attribute information indicates the second dynamic range, outputs the decoded video information and maximum luminance information indicating a maximum luminance of the video stream in accordance with the second dynamic range. Further, in other cases, the outputter outputs the decoded video information and maximum luminance information indicating the maximum luminance of all pictures in the video stream.