ABSTRACT
This chapter introduces sequences with an autocorrelation function of zero sidelobe such as perfect sequences and uniformly redundant arrays in “Sequences with Autocorrelation of Zero Sidelobe”. It presents the watermark embedding and extraction schemes in “Proposed Watermarking Technique”, with a new audio similarity measurement adopted. The chapter explains experimental results in “Experimental Results”. It discusses a high-capacity, real-time audio watermarking technique based on the spread spectrum approach. A sequence with autocorrelation of zero sidelobe is used as the direct sequence in spread spectrum communications. Because the only constraint in sequence generation is the odd symmetry of the phase spectrum, arbitrary lengths of perfect sequences are possible. Traditional objective and quantitative approaches used in digital images, such as mean-square-error, correlation, or signal-to-noise-ratio measurement, can hardly reflect the perceived audio similarity. The perfect sequence is used to scramble the watermark before watermark embedding. Sequences with autocorrelation function of zero sidelobe are introduced, investigated, and tested in the experiments.
