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// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant reason:default
#ifndef QIMAGESCALE_P_H
#define QIMAGESCALE_P_H
//
// W A R N I N G
// -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
#include <qimage.h>
#include <private/qtguiglobal_p.h>
#if QT_CONFIG(qtgui_threadpool)
#include <qthreadpool.h>
#include <private/qguiapplication_p.h>
#include <private/qlatch_p.h>
#include <private/qthreadpool_p.h>
#endif
QT_BEGIN_NAMESPACE
/*
This version accepts only supported formats.
*/
QImage qSmoothScaleImage(const QImage &img, int w, int h);
namespace QImageScale {
struct QImageScaleInfo {
int *xpoints{nullptr};
const unsigned int **ypoints{nullptr};
int *xapoints{nullptr};
int *yapoints{nullptr};
int xup_yup{0};
int sh = 0;
int sw = 0;
};
template<typename T>
void multithread_pixels_function(QImageScaleInfo *isi, int dh, const T &scaleSection)
{
#if QT_CONFIG(qtgui_threadpool)
int segments = (qsizetype(isi->sh) * isi->sw) / (1<<16);
segments = std::min(segments, dh);
QThreadPool *threadPool = QGuiApplicationPrivate::qtGuiThreadPool();
if (segments > 1 && threadPool && !threadPool->contains(QThread::currentThread())) {
QLatch latch(segments);
int y = 0;
for (int i = 0; i < segments; ++i) {
int yn = (dh - y) / (segments - i);
threadPool->start([&, y, yn]() {
scaleSection(y, y + yn);
latch.countDown();
});
y += yn;
}
latch.wait();
return;
}
#else
Q_UNUSED(isi);
#endif
scaleSection(0, dh);
}
}
QT_END_NAMESPACE
#endif