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// Copyright (C) 2025 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
#include <QtFFmpegMediaPluginImpl/private/qavfcamerarotationtracker_p.h>
#include <QtCore/qassert.h>
#include <AVFoundation/AVFoundation.h>
#include <cmath>
QT_BEGIN_NAMESPACE
namespace QFFmpeg {
AvfCameraRotationTracker::AvfCameraRotationTracker(AVCaptureDevice *avCaptureDevice)
{
Q_ASSERT(avCaptureDevice);
m_avCaptureDevice = AVFScopedPointer{ [avCaptureDevice retain] };
// Use RotationCoordinator if we can.
if (@available(macOS 14.0, iOS 17.0, *)) {
m_avRotationCoordinator = AVFScopedPointer{ [[AVCaptureDeviceRotationCoordinator alloc]
initWithDevice:m_avCaptureDevice
previewLayer:nil] };
}
}
AvfCameraRotationTracker::AvfCameraRotationTracker(AvfCameraRotationTracker &&other) noexcept
: m_avCaptureDevice{ std::exchange(other.m_avCaptureDevice, {}) }
{
if (@available(macOS 14.0, *)) {
m_avRotationCoordinator = std::exchange(other.m_avRotationCoordinator, {});
}
}
AvfCameraRotationTracker::~AvfCameraRotationTracker()
{
clear();
}
void AvfCameraRotationTracker::swap(AvfCameraRotationTracker &other)
{
std::swap(m_avCaptureDevice, other.m_avCaptureDevice);
if (@available(macOS 14.0, iOS 17.0, *)) {
std::swap(m_avRotationCoordinator, other.m_avRotationCoordinator);
}
}
void AvfCameraRotationTracker::clear()
{
if (m_avCaptureDevice)
m_avCaptureDevice.reset();
if (@available(macOS 14.0, *)) {
if (m_avRotationCoordinator) {
m_avRotationCoordinator.reset();
}
}
}
int AvfCameraRotationTracker::rotationDegrees() const
{
if (m_avCaptureDevice == nullptr)
return 0;
if (@available(macOS 14.0, *)) {
// This code assumes that AVCaptureDeviceRotationCoordinator
// .videoRotationAngleForHorizonLevelCapture returns degrees that are divisible by 90.
// This has been the case during testing.
//
// TODO: Some rotations are not valid for preview on some devices (such as
// iPhones not being allowed to have an upside-down window). This usage of the
// rotation coordinator will still return it as a valid preview rotation, and
// might cause bugs on iPhone previews.
if (m_avRotationCoordinator != nullptr)
return std::lround(
m_avRotationCoordinator.data().videoRotationAngleForHorizonLevelCapture);
}
return 0;
}
} // namespace QFFmpeg end
QT_END_NAMESPACE