A Watermarking Method for Speech Signals Based on the Time-Warping Signal Processing Concept

This paper deals with the watermarking of audio speech signals which consists in introducing an imperceptible mark in a signal. To this end, we suggest 10 use an amplitude modulated signal that mimics a formantic structure present in the signal. This allows to exploit the time-masking effect occurring when two signals are close in the time-frequency plane. From this embedding scheme, a watermark extraction method based on nonstationary linear filtering and matched filler detection is proposed in order to recover information carried by the watermark. Numerical results conducted on a real speech signal show that the watermark is likely not hearable and informations carried by the watermark are easily retrievable.