diff --git a/rtengine/dcrop.cc b/rtengine/dcrop.cc
index bc09f5348..85074fd96 100644
--- a/rtengine/dcrop.cc
+++ b/rtengine/dcrop.cc
@@ -19,6 +19,7 @@
  */
 
 #include "cieimage.h"
+#include "image8.h"
 #include "imagefloat.h"
 #include "labimage.h"
 #include "curves.h"
diff --git a/rtengine/dcrop.h b/rtengine/dcrop.h
index ff046dd68..c65c1e72f 100644
--- a/rtengine/dcrop.h
+++ b/rtengine/dcrop.h
@@ -21,7 +21,6 @@
 #include "improccoordinator.h"
 #include "rtengine.h"
 #include "improcfun.h"
-#include "image8.h"
 #include "imagesource.h"
 #include "procevents.h"
 #include "pipettebuffer.h"
@@ -30,6 +29,8 @@
 namespace rtengine
 {
 
+class Image8;
+
 using namespace procparams;
 
 class ImProcCoordinator;
diff --git a/rtengine/demosaic_algos.cc b/rtengine/demosaic_algos.cc
index 51db8bb3f..52e15be54 100644
--- a/rtengine/demosaic_algos.cc
+++ b/rtengine/demosaic_algos.cc
@@ -22,7 +22,6 @@
 #include "rawimagesource.h"
 #include "rawimage.h"
 #include "mytime.h"
-#include "image8.h"
 #include "rt_math.h"
 #include "color.h"
 #include "../rtgui/multilangmgr.h"
diff --git a/rtengine/gamutwarning.cc b/rtengine/gamutwarning.cc
index 3fc20d43a..fe6b7c0dc 100644
--- a/rtengine/gamutwarning.cc
+++ b/rtengine/gamutwarning.cc
@@ -23,9 +23,11 @@
  * also distributed under the GPL V3+
  */
 
-#include "gamutwarning.h"
 #include <iostream>
 
+#include "gamutwarning.h"
+#include "image8.h"
+
 namespace rtengine {
 
 GamutWarning::GamutWarning(cmsHPROFILE iprof, cmsHPROFILE gamutprof, RenderingIntent intent, bool gamutbpc):
diff --git a/rtengine/gamutwarning.h b/rtengine/gamutwarning.h
index e0aaa98d9..b7ac5e41d 100644
--- a/rtengine/gamutwarning.h
+++ b/rtengine/gamutwarning.h
@@ -27,10 +27,11 @@
 
 #include "iccstore.h"
 #include "noncopyable.h"
-#include "image8.h"
 
 namespace rtengine {
 
+class Image8;
+
 enum RenderingIntent : int;
 
 class GamutWarning: public NonCopyable {
diff --git a/rtengine/image8.h b/rtengine/image8.h
index 2fa2528ed..f125dccf8 100644
--- a/rtengine/image8.h
+++ b/rtengine/image8.h
@@ -19,11 +19,9 @@
 //
 // A class representing a 8 bit rgb image without alpha channel
 //
-#ifndef _IMAGE8_
-#define _IMAGE8_
+#pragma once
 
 #include "imageio.h"
-#include "rtengine.h"
 
 namespace rtengine
 {
@@ -104,4 +102,3 @@ public:
 };
 
 }
-#endif
diff --git a/rtengine/imagesource.h b/rtengine/imagesource.h
index 614e7c23c..428027bc0 100644
--- a/rtengine/imagesource.h
+++ b/rtengine/imagesource.h
@@ -26,7 +26,6 @@
 #include "colortemp.h"
 #include "coord2d.h"
 #include "dcp.h"
-#include "image8.h"
 #include "imagedata.h"
 #include "LUT.h"
 #include "rtengine.h"
diff --git a/rtengine/improccoordinator.cc b/rtengine/improccoordinator.cc
index d75f515bf..0ab015fd3 100644
--- a/rtengine/improccoordinator.cc
+++ b/rtengine/improccoordinator.cc
@@ -18,6 +18,7 @@
  */
 #include "improccoordinator.h"
 #include "cieimage.h"
+#include "image8.h"
 #include "imagefloat.h"
 #include "labimage.h"
 #include "curves.h"
diff --git a/rtengine/improccoordinator.h b/rtengine/improccoordinator.h
index 2969184bc..e7199565b 100644
--- a/rtengine/improccoordinator.h
+++ b/rtengine/improccoordinator.h
@@ -23,7 +23,6 @@
 
 #include "rtengine.h"
 #include "improcfun.h"
-#include "image8.h"
 #include "imagesource.h"
 #include "procevents.h"
 #include "dcrop.h"
@@ -33,6 +32,8 @@
 namespace rtengine
 {
 
+class Image8;
+
 using namespace procparams;
 
 class Crop;
diff --git a/rtengine/improcfun.h b/rtengine/improcfun.h
index 189722846..b3ba2ccb8 100644
--- a/rtengine/improcfun.h
+++ b/rtengine/improcfun.h
@@ -19,7 +19,6 @@
 #ifndef _IMPROCFUN_H_
 #define _IMPROCFUN_H_
 
-#include "image8.h"
 #include "shmap.h"
 #include "coord2d.h"
 #include "color.h"
@@ -33,6 +32,7 @@
 namespace rtengine
 {
 class CieImage;
+class Image8;
 class Imagefloat;
 class LabImage;
 class wavelet_decomposition;
diff --git a/rtengine/iplab2rgb.cc b/rtengine/iplab2rgb.cc
index c5c3f97d1..451a68a3f 100644
--- a/rtengine/iplab2rgb.cc
+++ b/rtengine/iplab2rgb.cc
@@ -17,6 +17,7 @@
  *  along with RawTherapee.  If not, see <https://www.gnu.org/licenses/>.
  */
 #include "rtengine.h"
+#include "image8.h"
 #include "imagefloat.h"
 #include "labimage.h"
 #include "improcfun.h"
diff --git a/rtengine/stdimagesource.cc b/rtengine/stdimagesource.cc
index c0befef7f..43628e074 100644
--- a/rtengine/stdimagesource.cc
+++ b/rtengine/stdimagesource.cc
@@ -21,6 +21,7 @@
 #include "color.h"
 #include "curves.h"
 #include "iccstore.h"
+#include "image8.h"
 #include "image16.h"
 #include "imagefloat.h"
 #include "imageio.h"
diff --git a/rtengine/stdimagesource.h b/rtengine/stdimagesource.h
index 2db2fdf57..632b84ccb 100644
--- a/rtengine/stdimagesource.h
+++ b/rtengine/stdimagesource.h
@@ -23,6 +23,9 @@
 
 namespace rtengine
 {
+
+class ImageIO;
+
 namespace procparams
 {