Semifragile Speech Watermarking Based on Least Significant Bit Replacement of Line Spectral Frequencies

Abstract

There are various techniques for speech watermarking based on modifying the linear prediction coefficients (LPCs); however, the estimated and modified LPCs vary from each other even without attacks. Because line spectral frequency (LSF) has less sensitivity to watermarking than LPC, watermark bits are embedded into the maximum number of LSFs by applying the least significant bit replacement (LSBR) method. To reduce the differences between estimated and modified LPCs, a checking loop is added to minimize the watermark extraction error. Experimental results show that the proposed semifragile speech watermarking method can provide high imperceptibility and that any manipulation of the watermark signal destroys the watermark bits since manipulation changes it to a random stream of bits.

An Effective Watermarking Method Based on Energy Averaging in Audio Signals

“…But the embedding capacity of both is again relatively limited. Nematollahi et al [17] presented a speech watermarking to embed watermark into line spectral frequency by least significant bit. Sarreshtedari and Akhaee [18] also applied self-embedding speech signals to protect against channel coding, but the original speech signal is required to extract the watermark.…”