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/*
dsp/RMS.h
Copyright 2004 Tim Goetze <tim@quitte.de>
http://quitte.de/dsp/
root-mean-square accumulator.
*/
/*
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA or point your web browser to http://www.gnu.org.
*/
#ifndef _DSP_RMS_H_
#define _DSP_RMS_H_
namespace DSP {
class RMS
{
public:
d_sample buffer[64];
int write;
double sum;
RMS()
{
write = 0;
reset();
}
void reset()
{
sum = 0.;
memset (buffer, 0, sizeof (buffer));
}
/* needs the squared sample value to be passed in */
d_sample process (d_sample x)
{
sum -= buffer[write];
sum += x;
write = (write + 1) & 63;
return sqrt (sum / 64);
}
};
} /* namespace DSP */
#endif /* _DSP_RMS_H_ */
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