[WM]: Re: Adding noise in audio file

["Krishnakumar S." <krishku@erdcitvm.org>]

Hi,

A simple straight forward method, is to shape your noise using the =
short-time spectral envelope of the audio signal. What it does
is to put more noise energy into those portions of the spectrum where =
the signal is strong and hence have a good masking effect.
If you want to be more accurate, you may use one of those =
psycho-acoustic models like the one used by MPEG Audio coders. Calculate
the masking thresholds and use this pattern to shape your random noise.

The shaping can be done using straight forward frequency-domain =
multiplication.

You may refer to the paper

Robust audio watermarking using perceptual masking
by Swanson, Zhu, Tewfik and Boney
Elsevier Signal Processing 66(1998) pp337-355

Regards
KK

----- Original Message -----
From: "HyoungJoong Kim" <khj@kangwon.ac.kr>
To: <watermarking@watermarkingworld.org>
Sent: Wednesday, March 26, 2003 3:35 PM
Subject: [WM]: Adding noise in audio file


>
> Dear all:
>
> I want to add random noise to the audio
> for spread-spectrum watermarking.
> However, the random noise may generate annoying audible noise. Thus, I =

> want to apply psychoacoustic filter to the random noise to suppress=20
> audible noise. Then, how can design psychoacoustic filter?
> Or can you give me filter coefficients?
> Any reply or pointer will be appreciated.
>
> Hyoung
>


______________________________________________________________________________

Watermarking Mailing List - http://www.watermarkingworld.org/ml.html
To unsubscribe send email to "majordomo@watermarkingworld.org" with
"unsubscribe watermarking YOURMAIL" in the body.
______________________________________________________________________________