diff --git a/rtengine/dcrop.h b/rtengine/dcrop.h
index 6ce034f3f..ff046dd68 100644
--- a/rtengine/dcrop.h
+++ b/rtengine/dcrop.h
@@ -22,7 +22,6 @@
 #include "rtengine.h"
 #include "improcfun.h"
 #include "image8.h"
-#include "image16.h"
 #include "imagesource.h"
 #include "procevents.h"
 #include "pipettebuffer.h"
diff --git a/rtengine/image16.cc b/rtengine/image16.cc
index 0cdcc578f..14ba4964d 100644
--- a/rtengine/image16.cc
+++ b/rtengine/image16.cc
@@ -16,11 +16,12 @@
  *  You should have received a copy of the GNU General Public License
  *  along with RawTherapee.  If not, see <https://www.gnu.org/licenses/>.
  */
+#include <cstdio>
+
 #include "image16.h"
 #include "imagefloat.h"
 #include "image8.h"
-#include <cstdio>
-#include "rtengine.h"
+#include "rt_math.h"
 
 namespace
 {
diff --git a/rtengine/image16.h b/rtengine/image16.h
index c16b7dd0d..d0053cbfc 100644
--- a/rtengine/image16.h
+++ b/rtengine/image16.h
@@ -19,11 +19,9 @@
 //
 // A class representing a 16 bit rgb image with separate planes and 16 byte aligned data
 //
-#ifndef _IMAGE16_
-#define _IMAGE16_
+#pragma once
 
 #include "imageio.h"
-#include "rtengine.h"
 
 namespace rtengine
 {
@@ -109,4 +107,3 @@ public:
 };
 
 }
-#endif
diff --git a/rtengine/imagesource.h b/rtengine/imagesource.h
index 065a2e582..614e7c23c 100644
--- a/rtengine/imagesource.h
+++ b/rtengine/imagesource.h
@@ -26,7 +26,6 @@
 #include "colortemp.h"
 #include "coord2d.h"
 #include "dcp.h"
-#include "image16.h"
 #include "image8.h"
 #include "imagedata.h"
 #include "LUT.h"
diff --git a/rtengine/improccoordinator.h b/rtengine/improccoordinator.h
index 379a3fb20..2969184bc 100644
--- a/rtengine/improccoordinator.h
+++ b/rtengine/improccoordinator.h
@@ -24,7 +24,6 @@
 #include "rtengine.h"
 #include "improcfun.h"
 #include "image8.h"
-#include "image16.h"
 #include "imagesource.h"
 #include "procevents.h"
 #include "dcrop.h"
diff --git a/rtengine/improcfun.h b/rtengine/improcfun.h
index 80e750a26..189722846 100644
--- a/rtengine/improcfun.h
+++ b/rtengine/improcfun.h
@@ -19,7 +19,6 @@
 #ifndef _IMPROCFUN_H_
 #define _IMPROCFUN_H_
 
-#include "image16.h"
 #include "image8.h"
 #include "shmap.h"
 #include "coord2d.h"
diff --git a/rtengine/stdimagesource.cc b/rtengine/stdimagesource.cc
index eddd12ae4..c0befef7f 100644
--- a/rtengine/stdimagesource.cc
+++ b/rtengine/stdimagesource.cc
@@ -21,6 +21,7 @@
 #include "color.h"
 #include "curves.h"
 #include "iccstore.h"
+#include "image16.h"
 #include "imagefloat.h"
 #include "imageio.h"
 #include "mytime.h"