Patent ID: 8768984

Claim:
A method of generating a media container file, said method comprising: a) organizing media data in said media container file, wherein the media container file comprises the media data to be transmitted to a client during a media session, said media data being defined by a media track in said media container file and comprises multiple media data portions constituting respective sub-streams; b) providing, in said media container file, sub-track information identifying, for each sub-track of multiple sub-tracks defined in said media track, the media data portion of said media data that belongs to said sub-track; and c) providing, in said media container file and for at least one sub-track of said multiple sub-tracks, selection information defining a selective processing of the media data portion defined by said at least one sub-track in relation to other media data organized in said media container file and relating to the same content as said media data portion defined by said at least one sub-track; wherein the selection information is used by a media server in connection with the media session to select the at least one sub-track and the media data portion used when the media data portion is switched during the media session, wherein said providing c) comprises providing, in said media container file and for said at least one sub-track of said multiple sub-tracks, an alternate group identifier applicable in connection with setting up a media session when selecting a sub-stream to be processed during said media session wherein said providing c) comprises providing, in said media container file and for said at least one sub-track of said multiple sub-tracks, a switch group identifier applicable when switching between different streams and/or sub-streams during an ongoing media session.