Patent attributes
The techniques described herein relate to methods, apparatus, and computer readable media configured to access multimedia data that has a hierarchical track structure that includes at least a first track at a first level of the hierarchical track structure comprising first media data, wherein the first media data comprises a first sequence of temporally-related media units, and a second track at a second level in the hierarchical track structure that is different than the first level of the first track, the second track comprising metadata specifying a temporal track derivation operation. The temporal track derivation operation is performed on a set of media units comprising at least the first sequence of temporally-related media units to temporally modify the set of media units to generate second media data for the second track, wherein the second media data comprises a second sequence of temporally-related media units from the set of media units.