Added decodeImageQML taken from https://github.com/dplanella/qzxing/blob/master/qzxing.cpp. This is to be used in Qt versions 5.0 and above. Code cleanup needs to be done as well as updates to the examples.

source/QZXing.h

@@ -87,18 +87,35 @@ public slots:
     QString decodeImageFromFile(QString imageFilePath, int maxWidth=-1, int maxHeight=-1, bool smoothTransformation = false);
 
     /**
-      * The decoding function accessible from QML
-      */
+     * The decoding function accessible from QML. (Suggested for Qt 4.x)
+     */
     QString decodeImageQML(QObject *item);
 
     /**
-      * The decoding function accessible from QML. Able to set the decoding
-      * of a portion of the image.
-      */
+     * The decoding function accessible from QML. Able to set the decoding
+     * of a portion of the image. (Suggested for Qt 4.x)
+     */
     QString decodeSubImageQML(QObject* item,
                               const double offsetX = 0 , const double offsetY = 0,
                               const double width = 0, const double height = 0);
 
+    /**
+     * The decoding function accessible from QML. (Suggested for Qt 5.x)
+     * Can be used to decode image from the Camera element preview by providing
+     * the following string: image://camera/preview_1
+     */
+    QString decodeImageQML(const QUrl &imageUrl);
+
+    /**
+     * The decoding function accessible from QML. Able to set the decoding
+     * of a portion of the image.
+     * Can be used to decode image from the Camera element preview by providing
+     * the following string: image://camera/preview_1
+     * (Suggested for Qt 5.x)
+     */
+    QString decodeSubImageQML(const QUrl &imageUrl,
+                              const double offsetX = 0, const double offsetY = 0,
+                              const double width = 0, const double height = 0);
     /**
       * Get the prossecing time in millisecond of the last decode operation.
       * Added mainly as a statistic measure.

source/qzxing.cpp

@@ -135,17 +135,17 @@ QString QZXing::decodeImage(QImage image, int maxWidth, int maxHeight, bool smoo
     }
     catch(zxing::Exception& e)
     {
-       emit decodingFinished(false);
-       processingTime = -1;
-       return "";
+        emit decodingFinished(false);
+        processingTime = -1;
+        return "";
     }
 }
 
 QString QZXing::decodeImageFromFile(QString imageFilePath, int maxWidth, int maxHeight, bool smoothTransformation)
 {
-	//used to have a check if this image exists
-	//but was removed because if the image file path doesn't point to a valid image
-	// then the QImage::isNull will return true and the decoding will fail eitherway.
+    //used to have a check if this image exists
+    //but was removed because if the image file path doesn't point to a valid image
+    // then the QImage::isNull will return true and the decoding will fail eitherway.
     return decodeImage(QImage(imageFilePath), maxWidth, maxHeight, smoothTransformation);
 }
 
@@ -169,6 +169,29 @@ QString QZXing::decodeSubImageQML(QObject* item,
     return decodeImage(img);
 }
 
+QString QZXing::decodeImageQML(const QUrl &imageUrl)
+{
+    return decodeSubImageQML(imageUrl);
+}
+QString QZXing::decodeSubImageQML(const QUrl &imageUrl,
+                                  const double offsetX, const double offsetY,
+                                  const double width, const double height)
+{
+    QString imagePath = imageUrl.path();
+    imagePath = imagePath.trimmed();
+    QFile file(imagePath);
+    if (!file.exists()) {
+        qDebug() << "[decodeSubImageQML()] The file" << file.fileName() << "does not exist.";
+        emit decodingFinished(false);
+        return "";
+    }
+    QImage img(imageUrl.path());
+    if(!(offsetX == 0 && offsetY == 0 && width == 0 && height == 0)) {
+        img = img.copy(offsetX, offsetY, width, height);
+    }
+    return decodeImage(img);
+}
+
 int QZXing::getProcessTimeOfLastDecoding()
 {
     return processingTime;