diff --git a/src/QtLocationPlugin/QGeoMapReplyQGC.cpp b/src/QtLocationPlugin/QGeoMapReplyQGC.cpp
index b07ad39..44ed968 100644
--- a/src/QtLocationPlugin/QGeoMapReplyQGC.cpp
+++ b/src/QtLocationPlugin/QGeoMapReplyQGC.cpp
@@ -52,9 +52,6 @@
 #include <QtNetwork/QNetworkAccessManager>
 #include <QFile>
 #include "TerrainTile.h"
-#include <QJsonDocument>
-#include <QJsonObject>
-#include <QJsonArray>
 
 int QGeoTiledMapReplyQGC::_requestCount = 0;
 
@@ -129,18 +126,13 @@ QGeoTiledMapReplyQGC::networkReplyFinished()
 
     // convert "a" to binary in case we have elevation data
     if ((UrlFactory::MapType)tileSpec().mapId() == UrlFactory::MapType::AirmapElevation) {
-        QJsonParseError parseError;
-        QJsonDocument json = QJsonDocument::fromJson(a, &parseError);
-        if (parseError.error != QJsonParseError::NoError) {
+
+        a = TerrainTile::serialize(a);
+        if (a.isEmpty()) {
             emit aborted();
             return;
-        } else {
-            a = TerrainTile::serialize(json);
-            if (a.isEmpty()) {
-                emit aborted();
-                return;
-            }
         }
+
     }
     setMapImageData(a);
     if(!format.isEmpty()) {
diff --git a/src/TerrainTile.cc b/src/TerrainTile.cc
index e1f772f..2a065e6 100644
--- a/src/TerrainTile.cc
+++ b/src/TerrainTile.cc
@@ -111,11 +111,17 @@ QGeoCoordinate TerrainTile::centerCoordinate(void) const
     return _southWest.atDistanceAndAzimuth(_southWest.distanceTo(_northEast) / 2.0, _southWest.azimuthTo(_northEast));
 }
 
-QByteArray TerrainTile::serialize(QJsonDocument document)
+QByteArray TerrainTile::serialize(QByteArray input)
 {
+    QJsonParseError parseError;
+    QJsonDocument document = QJsonDocument::fromJson(input, &parseError);
+    if (parseError.error != QJsonParseError::NoError) {
+        QByteArray emptyArray;
+        return emptyArray;
+    }
+
     QByteArray byteArray;
-    QIODevice::OpenMode writeonly = QIODevice::WriteOnly;
-    QDataStream stream(&byteArray, writeonly);
+    QDataStream stream(&byteArray, QIODevice::WriteOnly);
     if (!document.isObject()) {
         qCDebug(TerrainTileLog) << "Terrain tile json doc is no object";
         QByteArray emptyArray;
diff --git a/src/TerrainTile.h b/src/TerrainTile.h
index 84de079..faee055 100644
--- a/src/TerrainTile.h
+++ b/src/TerrainTile.h
@@ -89,7 +89,7 @@ public:
     *
     * @return serialized data
     */
-    static QByteArray serialize(QJsonDocument document);
+    static QByteArray serialize(QByteArray input);
 
 private:
     inline int _latToDataIndex(double latitude) const;
@@ -98,11 +98,11 @@ private:
     QGeoCoordinate      _southWest;                                     /// South west corner of the tile
     QGeoCoordinate      _northEast;                                     /// North east corner of the tile
 
-    int               _minElevation;                                  /// Minimum elevation in tile
-    int               _maxElevation;                                  /// Maximum elevation in tile
-    double            _avgElevation;                                  /// Average elevation of the tile
+    int               _minElevation;                                    /// Minimum elevation in tile
+    int               _maxElevation;                                    /// Maximum elevation in tile
+    double            _avgElevation;                                    /// Average elevation of the tile
 
-    double**             _data;                                          /// 2D elevation data array
+    double**            _data;                                          /// 2D elevation data array
     int                 _gridSizeLat;                                   /// data grid size in latitude direction
     int                 _gridSizeLon;                                   /// data grid size in longitude direction
     bool                _isValid;                                       /// data loaded is valid