Dynamic watermarking of media based on transport-stream metadata, to facilitate action by downstream entity

A computing system comprising:

• one or more communication interfaces through which to receive a packet-based transport stream carrying a media stream and through which to output along a media-distribution path at least a modified version of the media stream for transmission to a downstream entity;
• a processing unit;
• non-transitory data storage;
• and
• program instructions stored in the non-transitory data storage and executable by the processing unit to carry out operations including:
• obtaining, from the transport stream, metadata that is carried by the transport stream and that is not watermarked in the media stream, wherein the metadata specifies a splice time point in the media stream as a time-offset value measured from a point in the media stream where the metadata is carried, wherein obtaining the metadata from the transport stream comprises obtaining the specified splice time point from the transport stream;
• computing an absolute time point in the media stream, based on the obtained splice time point,
• generating the modified version of the media stream by at least (i) encoding in a watermark in the media stream the computed absolute time point and (ii) encoding at a specific time point in the media stream a timestamp of the specific time point, whereby the timestamp is usable by the downstream entity as a basis to establish synchronous lock in order to map the absolute time to time according to a clock of the downstream entity, and
• outputting, for transmission along the media-distribution path to the downstream entity, the modified version of the media stream.

A non-transitory computer-readable medium embodying instructions executable by a computing system to carry out operations including:

• receiving a packet-based transport stream carrying a media stream that defines media content and carrying metadata that is not watermarked in the media stream, wherein the metadata specifies a splice time point in the media stream as a time-offset value measured from a point in the media stream where the metadata is carried;
• obtaining from the transport stream, the metadata that is not watermarked in the media stream, wherein obtaining the metadata from the transport stream comprises obtaining the specified splice time point from the transport stream;
• computing an absolute time point in the media stream, based on the obtained splice time point;
• modifying the media stream by at least (i) encoding in a watermark in the media stream the computed absolute time point and (ii) encoding at a specific time point in the media stream a timestamp of the specific time point, whereby the timestamp is usable by a downstream entity as a basis to establish synchronous lock in order to map the absolute time to time according to a clock of the downstream entity;
• and
• outputting from the computing system, for transmission to the downstream entity, at least the modified media stream.