At least one of an initial probability density for a video and an initial granularity mapping for the video based upon the initial probability density are generated at an analytics server. The initial probability density is calculated according to a set of points in the video. A set of beacons is generated by the each of the plurality of the clients according to the at least one of the initial probability density and the initial granularity mapping during playback of the video based on a duration of the playback by the each of the plurality of the clients is received at the analytics server. Further, at least one of an updated probability density and an updated granularity mapping based upon the updated probability density are generated such that a quantity of beacons in the set of beacons is modified.