A method of retrieving media data, the method comprising: retrieving a manifest file for a media presentation, the manifest file including a manifest file element having an initialization set element, the initialization set element including initialization parameters for a full duration of the media presentation; initializing playback of media data of the media presentation using the initialization set element; retrieving the media data of the media presentation; and presenting the media data according to the initialized playback, wherein: the media presentation includes a plurality of periods, each of the periods including an adaptation set having a representation including media data that can be presented using the initialization parameters of the initialization set element and the initialized playback, the method further comprising determining the representations of the periods including the media data that can be presented using the initialization parameters and the initialized playback using data of the manifest file; the initialization parameters specify common attribute elements across the media presentation including one or more of a maximum width of pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element or a maximum height of the pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element. retrieving a manifest file for a media presentation, the manifest file including a manifest file element having an initialization set element, the initialization set element including initialization parameters for a full duration of the media presentation; initializing playback of media data of the media presentation using the initialization set element; retrieving the media data of the media presentation; and presenting the media data according to the initialized playback, wherein: the media presentation includes a plurality of periods, each of the periods including an adaptation set having a representation including media data that can be presented using the initialization parameters of the initialization set element and the initialized playback, the method further comprising determining the representations of the periods including the media data that can be presented using the initialization parameters and the initialized playback using data of the manifest file; the initialization parameters specify common attribute elements across the media presentation including one or more of a maximum width of pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element or a maximum height of the pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element. the media presentation includes a plurality of periods, each of the periods including an adaptation set having a representation including media data that can be presented using the initialization parameters of the initialization set element and the initialized playback, the method further comprising determining the representations of the periods including the media data that can be presented using the initialization parameters and the initialized playback using data of the manifest file; the initialization parameters specify common attribute elements across the media presentation including one or more of a maximum width of pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element or a maximum height of the pictures of the media presentation in all representations in all adaptation sets associated with the initialization set element.