AWT3 Watermark Listener - free AWT3 mobile app for Android
Before reading the below information on the AWT3 app, please refer to this short AWT3 technology description.
You can download detailed AWT3 User Guide (PDF) here.
AWT3 Watermark Listener is a supplementary application accompanying Audio Watermarking Tools 3 (AWT3). This application lets you use your portable Android device (phone, tablet) to detect inaudible digital codes (digital watermarks) in the audio content processed with patented* AWT3 watermarking technology.
Installation of the app is easy. You can search for the "AWT3 Watermark Listener" app in Google Play.
Or you can open this link on your Android device to install the application. Alternatively, you can download this APK file to your desktop PC and copy the file into your Android device manually, and then install it on the device by executing the APK file using any available file manager.
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 3-4 meters.
You can watch this short video showing the AWT3 Watermark Listener in action.
Make sure that watermark decoding parameters (such as expected watermark payload size and carrier frequency) are properly defined in the application Settings. The Settings screen can be accessed by touching the standard software or physical "Menu" button, like shown on the picture below:
The list below contains several audio files watermarked with different watermark payloads (specified in the file names). If you read this page using your desktop PC, you can experiment with AWT3 Listener by playing any of these files directly from this page via your PC multimedia speakers and checking watermark detection results on your Android device. Please note that 100% detection of watermarks with your particular setup cannot be guaranteed due to many different external factors (such as pecularities of different Android devices and their built-in microphone and audio systems, and so on). For your convenience, in addition to the live signal analysis in the "Live" mode of the app, you can also make recordings on the "Record" screen of the app and then perform manual analysis of the recorded audio files either using the "Analyze" button in the "Files" screen of the app, or using AWT3 file decoder on your PC.
Please note that all example audio tracks listed below carry 3-bytes long watermarks.
Audio example (music track) containing different watermark payloads. The watermark payload is changing every 5 seconds during playback (0x111111, 0x222222, 0x333333, 0x444444, 0x555555, 0x666666, 0x777777, 0x123456, 0xABCDEF, 0x086542, 0xAFED12, 0xFEDA12, 0x13AF56, 0x642ADC, 0xADCCCA):
Blonker-Castles_in_the_Air_changing_codes.wav |
More tracks broadcasting static (not changing) watermarks continuously during the whole playback time:
You need to use Audio Watermarking Tools 3 (AWT3) Encoder to embed your own arbitrary digital watermarks into your audio content.
Important! the recognition may not work well on some devices having poor microphone audio path quality. For example, some ZTE Android phone models don't capture sound frequencies above 12 KHz, which does not allow AWT3 Listener detecting AWT3 codes. Some other phones (such as Google Nexus One) may use dual-microphone noise cancellation that can also spoil the recognition. For such phones, the AWT3 Listener app would need to have a special treatment by disabling the internal dual-mic noise cancelling functionality, but such treatment was not included in the app for better compatibility with general phones.
The application is known to work well on Samsung Galaxy S2, S4.
Important! All the above demo songs carry 3-bytes long watermarks, and the Listener app expects 3-bytes watermarks by default. If you decide to test the app with different payload size, please make sure that you defined corresponding expected payload size in the app Settings.
More information on AWT3 technology and AWT3 evaluation package can be requested from the developer.
(*) U.S. Patent No. 8,116,514
