07587602 is referenced by 94 patents and cites 138 patents.

A portable device uses a microphone to listen to ambient audio, derives data from captured audio signals, and uses the derived data to request delivery of the audio or related information to the user's home or other location. The device is desirably pocket-sized, or suitable for carrying on a key-ring. The device may also detect a watermark signal that is present in the user's environment (e.g., played through a public address speaker system) to aid the user in recalling the context from which the audio was requested.

Title
Methods and devices responsive to ambient audio
Application Number
11/331430
Publication Number
7587602 (B2)
Application Date
January 11, 2006
Publication Date
September 8, 2009
Inventor
Geoffrey B Rhoads
West Linn
OR, US
Assignee
Digimarc Corporation
OR, US
IPC
H04L 9/00
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