Fixed compile warning from redefined macro.

modules/imgcodecs/src/grfmt_gdal.hpp

@@ -42,16 +42,15 @@
 #ifndef __GRFMT_GDAL_HPP__
 #define __GRFMT_GDAL_HPP__
 
+/// OpenCV FMT Base Type
+#include "grfmt_base.hpp"
+
 /// Macro to make sure we specified GDAL in CMake
 #ifdef HAVE_GDAL
 
 /// C++ Libraries
 #include <iostream>
 
-/// OpenCV Libraries
-#include "grfmt_base.hpp"
-#include "precomp.hpp"
-
 /// Geospatial Data Abstraction Library
 #include <gdal/cpl_conv.h>
 #include <gdal/gdal_priv.h>
@@ -61,6 +60,13 @@
 /// Start of CV Namespace
 namespace cv {
 
+/**
+ * Convert GDAL Pixel Range to OpenCV Pixel Range
+*/
+double range_cast( const GDALDataType& gdalType,
+                   const int& cvDepth,
+                   const double& value );
+
 /**
  * Convert GDAL Palette Interpretation to OpenCV Pixel Type
 */