Multi level high capacity data hiding technique for stereo audio

This novel multi level encoding technique is using psychoacoustical principles of binaural hearing in the phase spectrum of stereo signals. A frequency-dependent threshold of the interaural phase difference is computed, and then used to determine locations suitable for data insertion. Once established, the threshold is divided into several sublevels, each carrying few bits of data. The disturbance in the phase is done in a fashion that mimics the original signal thus introducing little noise. Listening tests have been performed to confirm that using this method results in a signal indistinguishable from the original audio. This technique provides payload of over 105 kb/s for CD-quality audio.