Title :
A hybrid pre-whitening technique for detection of additive spread spectrum watermarks in audio signals
Author :
Krishna Kumar, S. ; Sreenivas, Thippur
Author_Institution :
Centre for Dev. of Adv. Comput., Broadcast & Commun. Group, Trivandrum, India
Abstract :
Pre-whitening techniques are employed in blind correlation detection of additive spread spectrum watermarks in audio signals to reduce the host signal interference. A direct deterministic whitening (DDW) scheme is derived in this paper from the frequency domain analysis of the time domain correlation process. Our experimental studies reveal that, the Savitzky-Golay Whitening (SGW), which is otherwise inferior to DDW technique, performs better when the audio signal is predominantly lowpass. The novelty of this paper lies in exploiting the complementary nature to the two whitening techniques to obtain a hybrid whitening (HbW) scheme. In the hybrid scheme the DDW and SGW techniques are selectively applied, based on short time spectral characteristics of the audio signal. The hybrid scheme extends the reliability of watermark detection to a wider range of audio signals.
Keywords :
audio watermarking; correlation methods; frequency-domain analysis; interference (signal); time-domain analysis; DDW scheme; DDW technique; HbW scheme; SGWtechniques; Savitzky-Golay whitening; additive spread spectrum watermarks; audio signals; blind correlation detection; direct deterministic whitening scheme; frequency domain analysis; host signal interference; hybrid prewhitening technique; time domain correlation process; watermark detection; Additives; Correlation; Detectors; Signal processing; Time-domain analysis; Vectors; Watermarking;
Conference_Titel :
Signal Processing Conference, 2006 14th European
Conference_Location :
Florence