Patent Document ID: 9269362
Application ID: 13609149
Patent Status: 1

Claim One:
1. A computer-implemented method for performing at least one of embedding and extraction of audio watermark, the method comprising the following steps: segmenting an input audio signal into segments of fixed size; applying multilevel Discrete Wavelet Transform (DWT) on each segment of the input audio signal; decomposing each of said segments using multilevel Discrete Wavelet Transform (DWT) to retrieve detailed coefficients; forming a detail coefficient matrix of said detailed coefficients retrieved for each level of said decomposition; and applying Singular Value Decomposition (SVD) on said detail coefficient matrix to obtain three decomposed matrices including a left singular vector matrix, a right singular vector matrix and a singular value matrix containing four singular values S 1 , S 2 , S 3 and S 4 , and wherein the extraction of the audio watermark includes the following steps: determining a threshold value using said singular value S 1 , said singular value S 4 value and a scaling factor having pre-designated value alpha 1 using the formula Threshold value=(alpha 1 *(S 1 +S 4 )); extracting a watermark bit from each of said segments by comparing the singular value S 2 with said threshold value using the formula: 
 watermark bit=0, if S2<Threshold Value and 
 watermark bit=1, if S2>=Threshold Value; scrambling and error correction to eliminate errors in extraction of said watermark bit; and combining watermarked bits extracted from each of said segments to form the watermark.