an encoding device performing an encoding process according to an encoding scheme using a cts indicating time at which presentation or reproduction is performed , comprising : an encapsulator that generates a media unit in which one or more access units encoded by the encoding scheme are capsulated , and a transmitter that transmits information indicating an absolute time of an access unit included at a top portion of the media unit , in addition to the media unit , wherein the encapsulator adds a cts relative value to the n th access unit included in the media unit , the cts relative value being a difference between the cts of the n th access unit and the dts of the n + 1 th access unit .