Crediting exposure to media identified using source filtering

A method performed by an audience measurement computing system, the audience measurement computing system comprising a processor, the method comprising:

• determining a source identifier that identifies a media source from which media presented by a media presentation device at a media presentation environment is received;
• using meter hash keys and the source identifier as a basis to select, from stored reference hash keys generated based on reference signatures representing previously-identified media, a set of reference hash keys that match the meter hash keys and correspond to the source identifier, each reference hash key associated with a corresponding media identifier, wherein the meter hash keys are generated based on meter signatures representing the media;
• identifying the media by matching es subset of the meter signatures to at least a subset of reference signatures from which the set of reference hash keys selected using the meter hash keys and the source identifies were generated;
• and
• generating exposure data that credits exposure of an audience member at the media presentation environment to the identified media.

An audience measurement computing system comprising:

• a processor;
• and
• a non-transitory computer-readable storage medium, having stored thereon program instructions that, upon execution by the processor, cause performance of operations comprising:
• determining a source identifier that identifies a media source from which media presented by a media presentation device at a media presentation environment is received;
• using meter hash keys and the source identifier as a basis to select, from stored reference hash keys generated based on reference signatures representing previously-identified media, a set of reference hash keys that match the meter hash keys and correspond to the source identifier, each reference hash key associated with a corresponding media identifier, wherein the meter hash keys are generated based on meter signatures representing the media;
• identifying the media by matching at least subset of the meter signatures to at least a subset of reference signatures from which the set of reference hash keys selected using the meter hash keys and the source identifier were generated;
• and
• generating exposure data that credits exposure of an audience member at the media presentation environment to the identified media.