Semi Fragile Watermarking System in Temporal Domain for PCM Audio Signals

In this work, a watermark detection system for audio signals in temporal domain is proposed, the watermark embedding algorithm is the multiplicative embedding rule and the optimal detection equation is derived for this constraints using the maximum likelihood (ML) criterion. The optimal threshold equation is also derived using the Neyman-Person criterion and the resulting system is blind and has very low complexity. Computer simulations were performed applying the proposed model to audio signals and results show that the proposed system is semi fragile since it is able to detect watermarks if the watermarked object was severely attacked by noise, low pass filtering among other attacks but is not capable of detecting watermarks for others attacks such MP3 compression.