Auxiliary MPDs for MPEG DASH to support preroll and midrolls and their playback using W3C MSE/EME

An apparatus for signaling auxiliary media in a main dynamic adaptive streaming over HTTP (DASH) media stream, the apparatus comprising:

• at least one memory configured to store computer program code;
• at least one processor configured to access the computer program code and operate as instructed by the computer program code, the computer program code including:
• receiving code configured to cause the at least one processor to receive one or more MPD period elements and at least one auxiliary period element, the at least one auxiliary period element comprising a start time attribute, a return time offset attribute, and a media source extension (MSE) source buffer time stamp offset, the return time offset attribute representing an offset form a time in a media timeline that a main media segment is stopped to play media segment associated with the at least one auxiliary period element, and the MSE source buffer time stamp offset is equal to a presentation time offset associated with a respective auxiliary media segment;
• retrieving code configured to cause the at least one processor to retrieve one or more main media segments associated with the one or more MPD period elements and one or more auxiliary media segments associated with the at least one auxiliary period element;
• appending code configured to cause the at least one processor to append the one or more main media segments and the one or more auxiliary media segments to a media source extension (MSE) source buffer;
• and
• dispatching code configured to cause the at least one processor to dispatch the one or more auxiliary media segments and the one or more main media segments from the MSE source buffer based on the presentation time offset associated with the one or more auxiliary media segments and the one or more main media segments,
• wherein when an auxiliary media segment from the one or more auxiliary media segments is a pre-roll auxiliary media segment, the MSE source buffer time stamp offset is updated based on one or more of:
• a depth of a time shift buffer, the start time attribute associated with the auxiliary media segment, a total duration of all pre-roll media segments, a presentation time offset associated with a first main media segment of the one or more main media segments, and a threshold time range between a last pre-roll auxiliary media segment and the first main media segment.

A non-transitory computer-readable medium storing instructions, the instructions comprising:

• one or more instructions that, when executed by one or more processors of a device for signaling auxiliary media including pre-roll media content and mid-roll media content in a main dynamic adaptive streaming over HTTP (DASH) media stream, cause the one or more processors to:
• receive one or more main media presentation description (MPD) comprising one or more MPD period elements and at least one auxiliary period element, the at least one auxiliary period element comprising a start time attribute, a return time offset attribute, and a media source extension (MSE) source buffer time stamp offset, the return time offset attribute representing an offset form a time in a media timeline that a main media segment is stopped to play media segment associated with the at least one auxiliary period element, and the MSE source buffer time stamp offset is equal to a presentation time offset associated with a respective auxiliary media segment;
• retrieve one or more main media segments associated with the one or more MPD period elements and one or more auxiliary media segments associated with the at least one auxiliary period element;
• append the one or more main media segments and the one or more auxiliary media segments to a media source extension (MSE) source buffer;
• and
• dispatch the one or more auxiliary media segments and the one or more main media segments from the MSE source buffer based on the presentation time offset associated with the one or more auxiliary media segments and the one or more main media segments,
• wherein when an auxiliary media segment from the one or more auxiliary media segments is a pre-roll auxiliary media segment, the MSE source buffer time stamp offset is updated based on one or more of:
• a depth of a time shift buffer, the start time attribute associated with the auxiliary media segment, a total duration of all pre-roll media segments, a presentation time offset associated with a first main media segment of the one or more main media segments, and a threshold time range between a last pre-roll auxiliary media segment and the first main media segment.