Patent Document ID: 20160049153
Application ID: 14564267
Patent Status: 0

Claim One:
1 ) A computer implemented system for audio watermarking, said system comprising: a watermark embedding system for embedding a watermark in an audio signal, said watermark embedding system comprising: a first dividing module adapted to divide an audio signal into a plurality of audio frames, each frame being of pre-determined size and having a pre-determined number of samples of said audio signal; a first transforming module adapted to apply multi-level Discrete Wavelet Transform (DWT) on each frame to generate detailed coefficients and approximation coefficients at each level; a first arranging module adapted to arrange the generated detailed coefficients from all levels of DWT to form a matrix of detailed coefficients; a first decomposing module adapted to apply Singular Vector Decomposition (SVD) on said matrix of detailed coefficients to factor said matrix into at least a diagonal matrix; an embedding module adapted to embed a watermark bit with a scaling factor to a second Eigen value from top left to bottom right of said diagonal matrix to generate a modified diagonal matrix; a second decomposing module adapted to apply inverse SVD on at least said modified diagonal matrix to produce modified detailed coefficients; a second transforming module adapted to apply multi-level inverse DWT on the modified detailed coefficients and the generated approximation coefficients to create a watermarked audio frame; and a combining module adapted to combine each watermarked audio frame sequentially to produce a watermarked audio signal; and a watermark detection system for detecting the watermark from the watermarked audio signal, said watermark detecting system comprising: a synchronization module adapted to determine a synchronization point in the watermarked audio signal; a second dividing module adapted to divide the watermarked audio signal into a plurality of watermarked audio frames, each watermarked audio frame being of pre-determined size and having a pre-determined number of samples of the watermarked audio signal; a third transforming module adapted to apply multi-level DWT on each watermarked audio frame to generate watermarked detailed coefficients and watermarked approximation coefficients at each level; a second arranging module adapted to arrange the watermarked detailed coefficients from all levels of DWT to form a watermarked matrix of detailed coefficients; a third decomposing module adapted to apply SVD on said watermarked matrix of detailed coefficients to factor said watermarked matrix into at least a watermarked diagonal matrix; a detection module adapted to collect a second Eigen value of said watermarked diagonal matrix and storing the collected second Eigen value in an array; a correlation module adapted to correlate all the collected second Eigen values stored in said array with all watermarks pre-stored in the repository to generate correlated arrays proportionate to the watermarks pre-stored in the repository; a calculation module computes Peak to Sidelobe Ratio (PSR) from each correlation output; and a comparison module adapted to compare each calculated PSR with a pre-determined threshold to authenticate the embedded watermark.