Audio watermarking for people monitoring

A non-transitory computer-readable medium having stored thereon instructions that, when executed by a processor, cause performance of:

• obtaining a first audio signal detected by an acoustic sensor, wherein the first audio signal is indicative of audio in a vicinity of a monitored media device while the monitored media device presents media;
• detecting a first watermark included in the first audio signal, wherein the first watermark identifies the media presented by the monitored media device, and wherein the first watermark is emitted by the monitored media device while presenting the media;
• processing the first audio signal obtained from the acoustic sensor to determine whether a second watermark, different from the first watermark, is included in the first audio signal, wherein the second watermark identifies at least one of a mobile device or a user of the mobile device, and wherein the second watermark is emitted by the mobile device while the monitored media device is presenting the media;
• and
• generating a report based on the first watermark and the second watermark, wherein the report includes an indication that identifies the at least one of the mobile device or the user of the mobile device as being exposed to the media presented by the monitored media device.

A method comprising:

• obtaining a first audio signal detected by an acoustic sensor, wherein the first audio signal is indicative of audio in a vicinity of a monitored media device while the monitored media device presents media;
• detecting a first watermark included in the first audio signal, wherein the first watermark identifies the media presented by the monitored media device, and wherein the first watermark is emitted by the monitored media device while presenting the media;
• processing the first audio signal obtained from the acoustic sensor to determine whether a second watermark, different from the first watermark, is included in the first audio signal, wherein the second watermark identifies at least one of a mobile device or a user of the mobile device, and wherein the second watermark is emitted by the mobile device while the monitored media device is presenting the media;
• and
• generating a report based on the first watermark and the second watermark, wherein the report includes an indication that identifies the at least one of the mobile device or the user of the mobile device as being exposed to the media presented by the monitored media device.