Support QZXingFilter orientation respect proposed in #120. Could be usefull for #204

src/QZXingFilter.cpp

@@ -43,6 +43,7 @@ QZXingFilter::QZXingFilter(QObject *parent)
     : QAbstractVideoFilter(parent)
     , decoder(QZXing::DecoderFormat_QR_CODE)
     , decoding(false)
+    , orientation_(0)
 {
     /// Connecting signals to handlers that will send signals to QML
     connect(&decoder, &QZXing::decodingStarted,
@@ -69,6 +70,21 @@ void QZXingFilter::handleDecodingFinished(bool succeeded)
     emit isDecodingChanged();
 }
 
+void QZXingFilter::setOrientation(int orientation)
+{
+    if (orientation_ == orientation) {
+            return;
+        }
+
+        orientation_ = orientation;
+        emit orientationChanged(orientation_);
+}
+
+int QZXingFilter::orientation() const
+{
+    return orientation_;
+}
+
 QVideoFilterRunnable * QZXingFilter::createFilterRunnable()
 {
     return new QZXingFilterRunnable(this);
@@ -372,7 +388,20 @@ void QZXingFilterRunnable::processVideoFrameProbed(SimpleVideoFrame & videoFrame
 
     //QZXingImageProvider::getInstance()->storeImage(image);
 
-    decode(*image_ptr);
+    int orientation = filter ? filter->orientation() : 0;
+
+    if (!orientation) {
+        decode(*image_ptr);
+    } else {
+        QImage translatedImage = image_ptr->transformed([](QPoint center, int orientation) {
+                QMatrix matrix;
+                matrix.translate(center.x(), center.y());
+                matrix.rotate(-orientation);
+                return matrix;
+        } (image_ptr->rect().center(), orientation));
+
+        decode(translatedImage);
+    }
 
     delete image_ptr;
 }

src/QZXingFilter.h

@@ -75,16 +75,20 @@ class QZXingFilter : public QAbstractVideoFilter
         Q_PROPERTY(bool decoding READ isDecoding NOTIFY isDecodingChanged)
         Q_PROPERTY(QZXing* decoder READ getDecoder)
         Q_PROPERTY(QRectF captureRect MEMBER captureRect NOTIFY captureRectChanged)
+        Q_PROPERTY(int orientation READ orientation WRITE setOrientation NOTIFY orientationChanged)
 
     signals:
         void isDecodingChanged();
         void decodingFinished(bool succeeded, int decodeTime);
         void decodingStarted();
         void captureRectChanged();
+        void orientationChanged(int orientation);
 
     private slots:
         void handleDecodingStarted();
         void handleDecodingFinished(bool succeeded);
+        void setOrientation(int orientation);
+        int orientation() const;
 
     private: /// Attributes
         QZXing decoder;
@@ -93,6 +97,7 @@ class QZXingFilter : public QAbstractVideoFilter
 
         SimpleVideoFrame frame;
         QFuture<void> processThread;
+        int orientation_;
 
     public:  /// Methods
         explicit QZXingFilter(QObject *parent = 0);