Methods and apparatus to synthesize reference media signatures

A method, comprising:

• obtaining first constituent media signatures from a first media device that identify a first portion of media;
• obtaining second constituent media signatures from a second media device that identify a second portion of the media;
• and
• combining, by executing an instruction with a processor, the first constituent media signatures from the first media device and the second constituent media signatures from the second media device to form a reference media signature that identifies the media.

A non-transitory computer-readable storage medium comprising instructions that, when executed, cause a machine to at least:

• obtain first constituent media signatures from a first media device that identify a first portion of media;
• obtain second constituent media signatures from a second media device that identify a second portion of the media;
• and
• combine the first constituent media signatures from the first media device and the second constituent media signatures from the second media device to form a reference media signature that represents the media, the reference media signature for comparison with third constituent media signatures obtained from a third media device to detect consumption of the media at the third media device.