V_USASI generates N samples of USASI noise at sample frequency FS X=(N,FS)
0001 function x=v_usasi(n,fs) 0002 %V_USASI generates N samples of USASI noise at sample frequency FS X=(N,FS) 0003 0004 % This routine is based on the USASI noise defined in [1] which was later 0005 % reissued as [2]. USASI noise is intended to simulate the long-term average 0006 % of typical audio program material. The routine does not currently implement 0007 % the pulsation at 2.5Hz 12.5% duty cycle that is recommended by the standard. 0008 % Also it should probably be scaled to a well-defined power. 0009 % 0010 % [1] NRSC AM Reemphasis, Deemphasize, and Broadcast Audio Transmission Bandwidth Specifications, 0011 % EIA-549 Standard, Electronics Industries Association , July 1988. 0012 % [2] NRSC AM Reemphasis, Deemphasize, and Broadcast Audio Transmission Bandwidth Specifications, 0013 % NRSC-1-A Standard, Sept 2007, Online: http://www.nrscstandards.org/SG/NRSC-1-A.pdf 0014 0015 % Copyright (C) Mike Brookes 1997 0016 % Version: $Id: v_usasi.m 10865 2018-09-21 17:22:45Z dmb $ 0017 % 0018 % VOICEBOX is a MATLAB toolbox for speech processing. 0019 % Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 0020 % 0021 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0022 % This program is free software; you can redistribute it and/or modify 0023 % it under the terms of the GNU General Public License as published by 0024 % the Free Software Foundation; either version 2 of the License, or 0025 % (at your option) any later version. 0026 % 0027 % This program is distributed in the hope that it will be useful, 0028 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0029 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0030 % GNU General Public License for more details. 0031 % 0032 % You can obtain a copy of the GNU General Public License from 0033 % http://www.gnu.org/copyleft/gpl.html or by writing to 0034 % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 0035 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0036 0037 if nargin<2 fs=8000; end 0038 b=[1 0 -1]; 0039 a=poly(exp(-[100 320]*2*pi/fs)); 0040 0041 x=v_randfilt(b,a,n);