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/****************************************************************************
**
** Copyright (C) 2021 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:COMM$
**
** 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.
**
** $QT_END_LICENSE$
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
****************************************************************************/
#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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