Google has been awarded U.S. patent number 8138930, entitled "Advertising based on environmental conditions". The abstract describes the patent as: "Information about an environmental condition of a remote device is received, the environmental condition being determined based on a signal output from a sensor of the remote device or a sensor coupled to the remote device. An advertisement is identified based on the environmental condition, and the advertisement is provided to the remote device."
Filed back in January 2008, the patent suggests that Google has at the very least exercised the idea of using targeted advertisements based on background noise and conversations.
As claimed by the patent, this would be a computer-implemented method of receiving information "from a computing device" in which said device could be anything such as one or more of the following: "mobile phone, a personal computer, a digital billboard, a digital kiosk, or a vendor machine." The information could be gathered based on the environmental conditions and any set of search terms, be it through background noise and speech, captured images, or video signal.
The device would then use that data to target ads to the user. It seems that this could be based on location and other environmental conditions surrounding them. An example might be a soft drink company hitting you with a "Cool and refreshing" ad on a hot summer day in South Texas.
Advertisers, according to the patent, would bid on one or more keywords based on environmental conditions. Our fictional soft drink company could bid on words such as "hot," "scorching," and "thirsty" to ensure that ads reach people who might be likely to buy a cold drink.
This could also extend to billboards or digital kiosks for advertising to multiple people. On that same hot summer day, a large, prominent billboard in the area could change to advertise the soft drinks or a local water park. Much of this information could be gathered by receiving information based on surroundings.