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/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qmultimediautils_p.h"
QT_BEGIN_NAMESPACE
void qt_real_to_fraction(qreal value, int *numerator, int *denominator)
{
if (!numerator || !denominator)
return;
const int dMax = 1000;
int n1 = 0, d1 = 1, n2 = 1, d2 = 1;
qreal mid = 0.;
while (d1 <= dMax && d2 <= dMax) {
mid = qreal(n1 + n2) / (d1 + d2);
if (qAbs(value - mid) < 0.000001) {
if (d1 + d2 <= dMax) {
*numerator = n1 + n2;
*denominator = d1 + d2;
return;
} else if (d2 > d1) {
*numerator = n2;
*denominator = d2;
return;
} else {
*numerator = n1;
*denominator = d1;
return;
}
} else if (value > mid) {
n1 = n1 + n2;
d1 = d1 + d2;
} else {
n2 = n1 + n2;
d2 = d1 + d2;
}
}
if (d1 > dMax) {
*numerator = n2;
*denominator = d2;
} else {
*numerator = n1;
*denominator = d1;
}
}
QT_END_NAMESPACE
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