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#ifndef DSCAMERASESSION_H
#define DSCAMERASESSION_H

#include <QtCore/qobject.h>
#include <QTime>
#include <QUrl>
#include <QMutex>

#include <qcamera.h>
#include <QtMultimedia/qvideoframe.h>
#include <QtMultimedia/qabstractvideosurface.h>
#include <QtMultimedia/qvideosurfaceformat.h>
#include <QtMultimedia/qcameraimageprocessingcontrol.h>
#include <private/qmediastoragelocation_p.h>

#include <tchar.h>
#include <dshow.h>
#include <objbase.h>
#include <initguid.h>
#include "directshowmediatype.h"
#ifdef Q_CC_MSVC
#  pragma comment(lib, "strmiids.lib")
#  pragma comment(lib, "ole32.lib")
#endif // Q_CC_MSVC
#include <windows.h>

#ifdef Q_CC_MSVC
#  pragma include_alias("dxtrans.h","qedit.h")
#endif // Q_CC_MSVC
#define __IDxtCompositor_INTERFACE_DEFINED__
#define __IDxtAlphaSetter_INTERFACE_DEFINED__
#define __IDxtJpeg_INTERFACE_DEFINED__
#define __IDxtKey_INTERFACE_DEFINED__

struct ICaptureGraphBuilder2;

QT_BEGIN_NAMESPACE

class DirectShowSampleGrabber;

class DSCameraSession : public QObject
{
    Q_OBJECT
public:
    DSCameraSession(QObject *parent = 0);
    ~DSCameraSession();

    QCamera::Status status() const { return m_status; }

    void setDevice(const QString &device);

    bool load();
    bool unload();
    bool startPreview();
    bool stopPreview();

    bool isReadyForCapture();
    int captureImage(const QString &fileName);

    void setSurface(QAbstractVideoSurface* surface);

    QCameraViewfinderSettings viewfinderSettings() const;
    void setViewfinderSettings(const QCameraViewfinderSettings &settings);

    QList<QCameraViewfinderSettings> supportedViewfinderSettings() const
    { return m_supportedViewfinderSettings; }

    bool isImageProcessingParameterSupported(
            QCameraImageProcessingControl::ProcessingParameter) const;

    bool isImageProcessingParameterValueSupported(
            QCameraImageProcessingControl::ProcessingParameter,
            const QVariant &) const;

    QVariant imageProcessingParameter(
            QCameraImageProcessingControl::ProcessingParameter) const;

    void setImageProcessingParameter(
            QCameraImageProcessingControl::ProcessingParameter,
            const QVariant &);

Q_SIGNALS:
    void statusChanged(QCamera::Status);
    void imageExposed(int id);
    void imageCaptured(int id, const QImage &preview);
    void imageSaved(int id, const QString &fileName);
    void readyForCaptureChanged(bool);
    void captureError(int id, int error, const QString &errorString);

private Q_SLOTS:
    void presentFrame();
    void updateReadyForCapture();

private:
    struct ImageProcessingParameterInfo {
        ImageProcessingParameterInfo()
            : minimumValue(0)
            , maximumValue(0)
            , defaultValue(0)
            , currentValue(0)
            , capsFlags(0)
            , hasBeenExplicitlySet(false)
            , videoProcAmpProperty(VideoProcAmp_Brightness)
        {
        }

        LONG minimumValue;
        LONG maximumValue;
        LONG defaultValue;
        LONG currentValue;
        LONG capsFlags;
        bool hasBeenExplicitlySet;
        VideoProcAmpProperty videoProcAmpProperty;
    };

    void setStatus(QCamera::Status status);

    void onFrameAvailable(double time, quint8 *buffer, long len);
    void saveCapturedImage(int id, const QImage &image, const QString &path);

    bool createFilterGraph();
    bool connectGraph();
    void disconnectGraph();
    void updateSourceCapabilities();
    bool configurePreviewFormat();
    void updateImageProcessingParametersInfos();

    // These static functions are used for scaling of adjustable parameters,
    // which have the ranges from -1.0 to +1.0 in the QCameraImageProcessing API.
    static qreal scaledImageProcessingParameterValue(
            const ImageProcessingParameterInfo &sourceValueInfo);
    static qint32 sourceImageProcessingParameterValue(
            qreal scaledValue, const ImageProcessingParameterInfo &sourceValueInfo);

    QMutex m_presentMutex;
    QMutex m_captureMutex;

    // Capture Graph
    ICaptureGraphBuilder2* m_graphBuilder;
    IGraphBuilder* m_filterGraph;

    // Source (camera)
    QString m_sourceDeviceName;
    IBaseFilter* m_sourceFilter;
    bool m_needsHorizontalMirroring;
    QList<DirectShowMediaType> m_supportedFormats;
    QList<QCameraViewfinderSettings> m_supportedViewfinderSettings;
    DirectShowMediaType m_sourceFormat;
    QMap<QCameraImageProcessingControl::ProcessingParameter, ImageProcessingParameterInfo> m_imageProcessingParametersInfos;

    // Preview
    DirectShowSampleGrabber *m_previewSampleGrabber;
    IBaseFilter *m_nullRendererFilter;
    QVideoFrame m_currentFrame;
    bool m_previewStarted;
    QAbstractVideoSurface* m_surface;
    QVideoSurfaceFormat m_previewSurfaceFormat;
    QVideoFrame::PixelFormat m_previewPixelFormat;
    QSize m_previewSize;
    QCameraViewfinderSettings m_viewfinderSettings;
    QCameraViewfinderSettings m_actualViewfinderSettings;

    // Image capture
    QString m_imageCaptureFileName;
    QMediaStorageLocation m_fileNameGenerator;
    bool m_readyForCapture;
    int m_imageIdCounter;
    int m_currentImageId;
    QVideoFrame m_capturedFrame;

    // Internal state
    QCamera::Status m_status;

    friend class SampleGrabberCallbackPrivate;
};

QT_END_NAMESPACE


#endif