Abstract:

Reversible audio watermarking can restore the original audio data after extracting the watermark and be used for integrity verification and tamper detecting. A reversible fragile watermarking scheme was proposed for audio using intDCT (integer discrete cosine transform) and expansion embedding technology.  It is noting that a audio frame would be distorting after undergoing intDCT, amplitude expansion embedding and inverse intDCT. The reason of the distortion was analyzed and the corresponding solution was proposed.  Two reversible watermarking algorithms for audio integrity verification were  proposed. They employed two different embedding strategies, difference expansion embedding and prediction error expansion embedding in DCT highfrequency domain respectively. Experimental results show that the proposed algorithm can achieve less distortion and satisfied embedding capacity for integrity verification and tampering location.

Key words: audio; reversible watermarking; integer DCT; integrity verification; expansion embedding