imageanalyzer.h Example File

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  #ifndef IMAGEANALYZER_H
  #define IMAGEANALYZER_H

  #include <QFutureWatcher>
  #include <QtWidgets>

  class QNetworkAccessManager;
  class QNetworkReply;
  class QNetworkDiskCache;

  class ImageAnalyzer : public QObject
  {
      Q_OBJECT
  public:
      ImageAnalyzer(QNetworkDiskCache * netcache, QObject * parent=0);

      QRgb lastResults();
      float lastRed();
      float lastGreen();
      float lastBlue();
      bool isBusy();
      Q_PROPERTY(bool busy READ isBusy);
      Q_PROPERTY(float red READ lastRed);
      Q_PROPERTY(float green READ lastGreen);
      Q_PROPERTY(float blue READ lastBlue);
      ~ImageAnalyzer();

  public slots:
      /*! initiates analysis of all the urls in the list */
      void startAnalysis(const QStringList & urls);

  signals:
      void finishedAnalysis();
      void updateProgress(int completed, int total);

  private slots:
      void handleReply(QNetworkReply*);
      void doneProcessing();
      void progressStatus(int);

  private:
      QRgb processImages();
      void fetchURLs();
      void queueImage(QImage img);

  private:
      QNetworkAccessManager* m_network;
      QNetworkDiskCache* m_cache;
      QStringList m_URLQueue;
      QList<QImage> m_imageQueue;
      int m_outstandingFetches;
      QFutureWatcher<QRgb> * m_watcher;
  };

  QRgb averageRGB(const QImage &img);

  #endif