SECURE SPEECH WITH LFSR

Arathi K Chandran, Sreela Sreedhar

Abstract: Secure Speech with LFSR presents an encryption method for compressed and watermarked speech signal. There are several number of techniques available for watermarking, compression and encryption purpose, but there are various flaws in these techniques. Existing compression algorithms are very complicated and time consuming. Watermarking increases the size of the speech signal which in turn will affect the transmission of the speech signal. Previous encryption algorithms also increase the size of the signals, the security of the system can be easily compromised and these techniques are time consuming. Since the speech signals need to be transmitted and stored for future use, a good loss-less compression algorithm is needed to reduce the size of the speech signal and the lossless compression technique should be simpler and quicker. Because of compression, empty spaces are created within the speech signal. These empty spaces are used for embedding watermark signals into the speech signal. Then the compressed plus the watermarked signal is encrypted for making the signal more secure. Since the watermarked signal is encrypted, several attacks on the watermark signal can be reduced. Linear Feedback Shift Register is used for encryption purpose. Using Linear Feedback Shift Register the compressed plus watermarked signals are encrypted to form a cipher text and cipher text is transmitted .The transmitted cipher text is received by the receiver and decrypted using Linear Feedback Shift Register ,then the watermarked signal is extracted, the signal is decompressed and the speech is played back to the receiver

Keywords: Compression, Watermark, Encryption, Linear Feedback Shift Register and Cipher Text

DOI: https://doi.org/10.15623/ijret.2014.0313010