case wxIMAGE_RESOLUTION_INCHES:
             // convert resolution in inches to resolution in centimeters
-            hres *= 100*mm2inches;
-            vres *= 100*mm2inches;
+            hres = (wxUint32)(100*mm2inches*hres);
+            vres = (wxUint32)(100*mm2inches*vres);
             // fall through to convert it to resolution in meters
 
         case wxIMAGE_RESOLUTION_CM:
 
         {
             float xres, yres;
             if ( TIFFGetField(tif, TIFFTAG_XRESOLUTION, &xres) )
-                image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, xres);
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, wxRound(xres));
 
             if ( TIFFGetField(tif, TIFFTAG_YRESOLUTION, &yres) )
-                image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, yres);
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, wxRound(yres));
         }
     }