diff --git a/rtengine/image16.cc b/rtengine/image16.cc
index f0c8aa6b3..47b365dd8 100644
--- a/rtengine/image16.cc
+++ b/rtengine/image16.cc
@@ -271,3 +271,10 @@ Image16::tofloat() const
 	}
 	return imgfloat;
 }
+
+// Parallized transformation; create transform with cmsFLAGS_NOCACHE!
+void Image16::ExecCMSTransform(cmsHTRANSFORM hTransform) {
+    #pragma omp parallel for
+    for (int i=0; i<height; i++)
+        cmsDoTransform(hTransform, data + 3*i*rowstride, data + 3*i*rowstride, rowstride);
+}
\ No newline at end of file
diff --git a/rtengine/image16.h b/rtengine/image16.h
index d9ae7d23d..ce9b88119 100644
--- a/rtengine/image16.h
+++ b/rtengine/image16.h
@@ -58,7 +58,7 @@ class Image16 : public ImageIO, public IImage16 {
         Image16* copy ();
 
 		Image8* to8() const;
-	Imagefloat* tofloat() const;
+        Imagefloat* tofloat() const;
 
         Image16* rotate (int deg);
         Image16* hflip ();
@@ -87,6 +87,8 @@ class Image16 : public ImageIO, public IImage16 {
         virtual unsigned short** getRPlane () { return r; }
         virtual unsigned short** getGPlane () { return g; }
         virtual unsigned short** getBPlane () { return b; }
-};
+
+        void ExecCMSTransform(cmsHTRANSFORM hTransform);
+    };
 };
 #endif
diff --git a/rtengine/imagefloat.cc b/rtengine/imagefloat.cc
index 7e6bf48bd..7124b4dfb 100644
--- a/rtengine/imagefloat.cc
+++ b/rtengine/imagefloat.cc
@@ -21,6 +21,7 @@
 #include <image8.h>
 #include <string.h>
 #include <rtengine.h>
+#include <mytime.h>
 
 using namespace rtengine;
 
@@ -234,4 +235,9 @@ Imagefloat::to16() const
 	return img16;
 }
 
-
+// Parallized transformation; create transform with cmsFLAGS_NOCACHE!
+void Imagefloat::ExecCMSTransform(cmsHTRANSFORM hTransform) {
+    #pragma omp parallel for
+    for (int i=0; i<height; i++)
+        cmsDoTransform(hTransform, data + 3*i*rowstride, data + 3*i*rowstride, rowstride);
+}
diff --git a/rtengine/imagefloat.h b/rtengine/imagefloat.h
index 8ddf953f6..1f3d5a201 100644
--- a/rtengine/imagefloat.h
+++ b/rtengine/imagefloat.h
@@ -58,8 +58,8 @@ class Imagefloat : public ImageIO, public IImagefloat {
 
         Imagefloat* copy ();
 	
-	Image8* to8() const;
-	Image16* to16() const;
+        Image8* to8() const;
+        Image16* to16() const;
 
 
         Imagefloat* rotate (int deg);
@@ -70,25 +70,27 @@ class Imagefloat : public ImageIO, public IImagefloat {
         virtual int     getW            () { return width;  }
         virtual int     getH            () { return height; }
         virtual void    allocate        (int width, int height);
-	virtual int     getBPS          () { return 8*sizeof(float); }
-	//virtual void    getScanline     (int row, unsigned char* buffer, int bps);
-	//virtual void    setScanline     (int row, unsigned char* buffer, int bps);
+        virtual int     getBPS          () { return 8*sizeof(float); }
+        //virtual void    getScanline     (int row, unsigned char* buffer, int bps);
+        //virtual void    setScanline     (int row, unsigned char* buffer, int bps);
 
         // functions inherited from IImagefloat:
         virtual int getWidth ()  { return width; }
         virtual int getHeight () { return height; }
-	virtual Glib::Mutex& getMutex () { return mutex (); }
-	virtual cmsHPROFILE getProfile () { return getEmbeddedProfile (); }
-	virtual int getBitsPerPixel () { return 16; }
-	virtual int saveToFile (Glib::ustring fname) { return save (fname); }
-	virtual int saveAsPNG  (Glib::ustring fname, int compression = -1, int bps = -1) { return savePNG (fname, compression, bps); }
-	virtual int saveAsJPEG (Glib::ustring fname, int quality = 100) { return saveJPEG (fname, quality); }
-	virtual int saveAsTIFF (Glib::ustring fname, int bps = -1, bool uncompressed = false) { return saveTIFF (fname, bps, uncompressed); }
-	virtual void setSaveProgressListener (ProgressListener* pl) { return setProgressListener (pl); } 
+        virtual Glib::Mutex& getMutex () { return mutex (); }
+        virtual cmsHPROFILE getProfile () { return getEmbeddedProfile (); }
+        virtual int getBitsPerPixel () { return 16; }
+        virtual int saveToFile (Glib::ustring fname) { return save (fname); }
+        virtual int saveAsPNG  (Glib::ustring fname, int compression = -1, int bps = -1) { return savePNG (fname, compression, bps); }
+        virtual int saveAsJPEG (Glib::ustring fname, int quality = 100) { return saveJPEG (fname, quality); }
+        virtual int saveAsTIFF (Glib::ustring fname, int bps = -1, bool uncompressed = false) { return saveTIFF (fname, bps, uncompressed); }
+        virtual void setSaveProgressListener (ProgressListener* pl) { return setProgressListener (pl); } 
         virtual void free () { delete this; }
         virtual float** getRPlane () { return r; }
         virtual float** getGPlane () { return g; }
         virtual float** getBPlane () { return b; }
-};
+
+        void ExecCMSTransform(cmsHTRANSFORM hTransform);
+    };
 };
 #endif
diff --git a/rtengine/rawimagesource.cc b/rtengine/rawimagesource.cc
index bf99fc390..fc5869974 100644
--- a/rtengine/rawimagesource.cc
+++ b/rtengine/rawimagesource.cc
@@ -1574,7 +1574,7 @@ void RawImageSource::colorSpaceConversion (Imagefloat* im, ColorManagementParams
                 for (int k=0; k<3; k++) 
                     mat[i][j] += work[i][k] * camMatrix[k][j]; // rgb_xyz * xyz_cam
 
-#pragma omp parallel for
+        #pragma omp parallel for
         for (int i=0; i<im->height; i++)
             for (int j=0; j<im->width; j++) {
 
@@ -1587,8 +1587,9 @@ void RawImageSource::colorSpaceConversion (Imagefloat* im, ColorManagementParams
                 im->b[i][j] = (newb);
 
             }
-    } else {// use supplied input profile
-		//color space transform is expecting data in the range (0,1)
+    } else {
+        // use supplied input profile
+		// color space transform is expecting data in the range (0,1)
 		for ( int h = 0; h < im->height; ++h )
 			for ( int w = 0; w < im->width; ++w ) {
 				im->r[h][w] /= 65535.0f ;
@@ -1597,14 +1598,19 @@ void RawImageSource::colorSpaceConversion (Imagefloat* im, ColorManagementParams
 			}
         out = iccStore->workingSpace (cmp.working);
 //        out = iccStore->workingSpaceGamma (wProfile);
+
         lcmsMutex->lock ();
-        cmsHTRANSFORM hTransform = cmsCreateTransform (in, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent, 0);    
+        cmsHTRANSFORM hTransform = cmsCreateTransform (in, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent, 
+            cmsFLAGS_NOCACHE );  // NOCACHE is important for thread safety
         lcmsMutex->unlock ();
-        if (hTransform) {//there is an input profile
+
+        if (hTransform) {
+            // there is an input profile
             if (cmp.gammaOnInput) {
                 float gd = pow (2.0, defgain);
-                defgain = 0.0;// Writeback defgain to be 0.0
-#pragma omp parallel for
+                defgain = 0.0; // Writeback defgain to be 0.0
+
+                #pragma omp parallel for
                 for (int i=0; i<im->height; i++)
                     for (int j=0; j<im->width; j++) {
 						//TODO: extend beyond 65535
@@ -1613,21 +1619,28 @@ void RawImageSource::colorSpaceConversion (Imagefloat* im, ColorManagementParams
                         im->b[i][j] = CurveFactory::gamma (CLIP(gd*im->b[i][j]));
                     }
             }
-            cmsDoTransform (hTransform, im->data, im->data, im->planestride);
-        } else {//create the profile
+
+            im->ExecCMSTransform(hTransform);
+        } else {
+          // create the profile from camera
           lcmsMutex->lock ();
-          hTransform = cmsCreateTransform (camprofile, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent, cmsFLAGS_NOOPTIMIZE);    
+          hTransform = cmsCreateTransform (camprofile, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent,
+              cmsFLAGS_NOOPTIMIZE | cmsFLAGS_NOCACHE );  // NOCACHE is important for thread safety    
           lcmsMutex->unlock ();
-          cmsDoTransform (hTransform, im->data, im->data, im->planestride);
+
+          im->ExecCMSTransform(hTransform);
         }
-		//restore normalization to the range (0,65535)
+
+        cmsDeleteTransform(hTransform);
+
+		// restore normalization to the range (0,65535)
+        #pragma omp parallel for
 		for ( int h = 0; h < im->height; ++h )
 			for ( int w = 0; w < im->width; ++w ) {
 				im->r[h][w] *= 65535.0 ;
 				im->g[h][w] *= 65535.0 ;
 				im->b[h][w] *= 65535.0 ;
 			}
-        cmsDeleteTransform(hTransform);
     }
         t3.set ();
 //        printf ("ICM TIME: %d\n", t3.etime(t1));
@@ -1642,9 +1655,8 @@ void RawImageSource::colorSpaceConversion16 (Image16* im, ColorManagementParams
 	if (cmp.input == "(none)")
 		return;
 	
-	MyTime t1, t2, t3;
-	
-	t1.set ();
+	//MyTime t1, t2, t3;
+	//t1.set ();
 	
 	cmsHPROFILE in;
 	cmsHPROFILE out;
@@ -1697,13 +1709,15 @@ void RawImageSource::colorSpaceConversion16 (Image16* im, ColorManagementParams
 		out = iccStore->workingSpace (cmp.working);
 		//        out = iccStore->workingSpaceGamma (wProfile);
 		lcmsMutex->lock ();
-		cmsHTRANSFORM hTransform = cmsCreateTransform (in, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, 0);    
+		cmsHTRANSFORM hTransform = cmsCreateTransform (in, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, cmsFLAGS_NOCACHE);  // NOCACHE is important for thread safety
 		lcmsMutex->unlock ();
+
 		if (hTransform) {
 			if (cmp.gammaOnInput) {
 				float gd = pow (2.0, defgain);
 				defgain = 0.0;
-#pragma omp parallel for
+
+                #pragma omp parallel for
 				for (int i=0; i<im->height; i++)
 					for (int j=0; j<im->width; j++) {
 						im->r[i][j] = CurveFactory::gamma ((gd*im->r[i][j]));
@@ -1711,17 +1725,21 @@ void RawImageSource::colorSpaceConversion16 (Image16* im, ColorManagementParams
 						im->b[i][j] = CurveFactory::gamma ((gd*im->b[i][j]));
 					}
 			}
-			cmsDoTransform (hTransform, im->data, im->data, im->planestride);
+
+			im->ExecCMSTransform(hTransform);
 		}
 		else {
 			lcmsMutex->lock ();
-			hTransform = cmsCreateTransform (camprofile, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, 0);    
+			hTransform = cmsCreateTransform (camprofile, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, cmsFLAGS_NOCACHE);   
 			lcmsMutex->unlock ();
-			cmsDoTransform (hTransform, im->data, im->data, im->planestride);
+
+			im->ExecCMSTransform(hTransform);
 		}
+
 		cmsDeleteTransform(hTransform);
 	}
-	t3.set ();
+
+	//t3.set ();
 	//        printf ("ICM TIME: %d\n", t3.etime(t1));
 }
 
diff --git a/rtengine/stdimagesource.cc b/rtengine/stdimagesource.cc
index dcfde2d6e..820dba25f 100644
--- a/rtengine/stdimagesource.cc
+++ b/rtengine/stdimagesource.cc
@@ -315,10 +315,13 @@ void StdImageSource::colorSpaceConversion (Imagefloat* im, ColorManagementParams
 	
 	if (cmp.input!="(none)") {
 		lcmsMutex->lock ();
-		cmsHTRANSFORM hTransform = cmsCreateTransform (in, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent, cmsFLAGS_NOOPTIMIZE);
+		cmsHTRANSFORM hTransform = cmsCreateTransform (in, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), out, (FLOAT_SH(1)|COLORSPACE_SH(PT_RGB)|CHANNELS_SH(3)|BYTES_SH(4)|PLANAR_SH(1)), settings->colorimetricIntent, 
+            cmsFLAGS_NOOPTIMIZE | cmsFLAGS_NOCACHE);
 		lcmsMutex->unlock ();
-		cmsDoTransform (hTransform, im->data, im->data, im->planestride);
-		cmsDeleteTransform(hTransform);
+		
+        im->ExecCMSTransform(hTransform);
+		
+        cmsDeleteTransform(hTransform);
 	}
 }
 	
@@ -350,9 +353,11 @@ void StdImageSource::colorSpaceConversion16 (Image16* im, ColorManagementParams
 
     if (cmp.input!="(none)") {
         lcmsMutex->lock ();
-        cmsHTRANSFORM hTransform = cmsCreateTransform (in, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, 0);
+        cmsHTRANSFORM hTransform = cmsCreateTransform (in, TYPE_RGB_16_PLANAR, out, TYPE_RGB_16_PLANAR, settings->colorimetricIntent, cmsFLAGS_NOCACHE);
         lcmsMutex->unlock ();
-        cmsDoTransform (hTransform, im->data, im->data, im->planestride);
+        
+        im->ExecCMSTransform(hTransform);
+        
         cmsDeleteTransform(hTransform);
     }
 }