  The secure transmission of speech information is a significant issue faced by
many security professionals and individuals. By applying voice-encryption
technique any kind of encrypted sensitive speech data such as password can be
transmitted. But this has the serious disadvantage that by means of
cryptanalysis attack encrypted data can be compromised. Increasing the strength
of encryption/decryption results in an associated increased in the cost.
Additional techniques like stenography and digital watermarking can be used to
conceal information in an undetectable way in audio data. However this
watermarked audio data has to be send through unreliable media and an
eavesdropper might get hold of secret message and can also determine the
identity of a speaker who is sending the information since human voice contains
information based on its characteristics such as frequency, pitch, and energy.
This paper proposes Normalized Speech Watermarking technique. Speech signal is
normalized to hide the identity of the speaker who is sending the information
and then speech watermarking technique is applied on this normalized signal
that contains the message (password) so that what information is transmitted
should not be unauthorizedly revealed.
