Patent ID: 7925773

Claim:
A computer-readable storage device, comprising: a computer program that, when executed on a computing device, is configured to store a data stream in memory of the computing device in a virtual file format, the virtual file format including a timeline of events, wherein the event type is selected from the group consisting of media sample, seekpoint, and state table, and wherein events of the seekpoint and state table type are spanning events, the events in the timeline including a plurality of spanning events, each spanning event containing respective state information representing a state of the data stream across an interval in the timeline, and being linked to at least one other spanning event; wherein each of the spanning events is configured to contain a pointer that refers to a byte offset of a previous spanning event in the timeline, if present; wherein the computer program is configured to recover an attribute of a state of the data stream at a target position within the data stream, by accessing a spanning event with current state information for the attribute, and reading the state information from the spanning event; and wherein the computer program is configured to access a spanning event with current state information for the attribute by identifying a seekpoint spanning event associated with the target position, identifying a pointer in the seekpoint spanning event to a previous spanning event in the timeline, accessing the previous spanning event via the pointer, and reading state information from the previous event.