Non compressing png writer is ok.

src/image/Image.cpp

@@ -22,6 +22,16 @@ void Image<T>::initialize()
     mData = std::vector<T>(getBytesPerRow()*mHeight, 10);
 }
 
+template<typename T>
+void Image<T>::setDataItem(std::size_t index, T item)
+{
+    if(index >= mData.size())
+    {
+        return;
+    }
+    mData[index] = item;
+}
+
 template<typename T>
 void Image<T>::setPixelValue(unsigned idx, unsigned jdx, const Color& color)
 {