AWT3 Watermark Listener is a supplementary application accompanying Audio Watermarking Tools 3 (AWT3) of audiowatermarking.info. This application lets you use your portable Android device to detect inaudible digital codes (digital watermarks) in the audio content processed with AWT3 watermarking technology.

Digital audio watermarks are imperceptible digital signatures embedded into sound content. Digital watermark is usually a few bytes of data that carries some important information such as content author’s digital signature or ID of content recipient. AWT3 watermarks cannot be heard by human ear, but AWT3 Watermark Listener running on your device can “hear” and detect them.

Launch the application, switch to "Live" mode, point the device towards the sound source (multimedia speakers of your PC, TV set, etc.), press "Start listening" button and hold the device steady for a few seconds. Once a watermark is found, it is immediately shown on the screen. Recommended distance to the speakers is up to 3 meters. Make sure that watermark decoding parameters (such as watermark payload size and carrier frequency) are properly defined in the application Settings.

Audio examples and AWT3 software is available upon request.

U.S. Patent No. 8,116,514
(c)Alex Radzishevsky, http://audiowatermarking.info

web-resources: http://audiowatermarking.info, http://trustedaudio.com