diff --git a/rtengine/iimage.h b/rtengine/iimage.h
index e7dd5865d..1f82ea3e6 100644
--- a/rtengine/iimage.h
+++ b/rtengine/iimage.h
@@ -818,33 +818,21 @@ public:
                 }
             }
         } else if (interp == TI_Bilinear) {
-            for (int i = 0; i < nh; i++) {
-                int sy = i * height / nh;
+            float heightByNh = float(height) / float(nh);
+            float widthByNw = float(width) / float(nw);
+            float syf = 0.f;
 
-                if (sy >= height) {
-                    sy = height - 1;
-                }
+            for (int i = 0; i < nh; i++, syf += heightByNh) {
+                int sy = syf;
+                float dy = syf - float(sy);
+                int ny = sy < height - 1 ? sy + 1 : sy;
 
-                float dy = float(i) * float(height) / float(nh) - float(sy);
-                int ny = sy + 1;
+                float sxf = 0.f;
 
-                if (ny >= height) {
-                    ny = sy;
-                }
-
-                for (int j = 0; j < nw; j++) {
-                    int sx = j * width / nw;
-
-                    if (sx >= width) {
-                        sx = width;
-                    }
-
-                    float dx = float(j) * float(width) / float(nw) - float(sx);
-                    int nx = sx + 1;
-
-                    if (nx >= width) {
-                        nx = sx;
-                    }
+                for (int j = 0; j < nw; j++, sxf += widthByNw) {
+                    int sx = sxf;
+                    float dx = sxf - float(sx);
+                    int nx = sx < width - 1 ? sx + 1 : sx;
 
                     convertTo(r(sy, sx) * (1.f - dx) * (1.f - dy) + r(sy, nx)*dx * (1.f - dy) + r(ny, sx) * (1.f - dx)*dy + r(ny, nx)*dx * dy, imgPtr->r(i, j));
                     convertTo(g(sy, sx) * (1.f - dx) * (1.f - dy) + g(sy, nx)*dx * (1.f - dy) + g(ny, sx) * (1.f - dx)*dy + g(ny, nx)*dx * dy, imgPtr->g(i, j));