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/*
* This file is part of AtracDEnc.
*
* AtracDEnc is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* AtracDEnc 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with AtracDEnc; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "atrac_psy_common.h"
namespace NAtracDEnc {
//returns 1 for tone-like, 0 - noise-like
TFloat AnalizeScaleFactorSpread(const std::vector<TScaledBlock>& scaledBlocks) {
TFloat s = 0.0;
for (size_t i = 0; i < scaledBlocks.size(); ++i) {
s += scaledBlocks[i].ScaleFactorIndex;
}
s /= scaledBlocks.size();
TFloat sigma = 0.0;
TFloat t = 0.0;
for (size_t i = 0; i < scaledBlocks.size(); ++i) {
t = (scaledBlocks[i].ScaleFactorIndex - s);
t *= t;
sigma += t;
}
sigma /= scaledBlocks.size();
sigma = sqrt(sigma);
if (sigma > 14.0)
sigma = 14.0;
return sigma/14.0;
}
} //namespace NAtracDEnc
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