diff --git a/rtengine/color.h b/rtengine/color.h
index 31c361c86..1e1cb9679 100644
--- a/rtengine/color.h
+++ b/rtengine/color.h
@@ -230,7 +230,36 @@ public:
     * @param v value channel [0 ; 1] (return value)
     */
     static void rgb2hsv (float r, float g, float b, float &h, float &s, float &v);
+    
+    static inline void rgb2hsvdcp(float r, float g, float b, float &h, float &s, float &v)
+    {
 
+        float var_Min = min(r, g, b);
+        float var_Max = max(r, g, b);
+        float del_Max = var_Max - var_Min;
+        v = var_Max / 65535.f;
+
+        if (fabsf(del_Max) < 0.00001f) {
+            h = 0.f;
+            s = 0.f;
+        } else {
+            s = del_Max / var_Max;
+
+            if ( r == var_Max ) {
+                h = (g - b) / del_Max;
+            } else if ( g == var_Max ) {
+                h = 2.f + (b - r) / del_Max;
+            } else { /*if ( b == var_Max ) */
+                h = 4.f + (r - g) / del_Max;
+            }
+
+            if ( h < 0.f ) {
+                h += 6.f;
+            } else if ( h > 6.f ) {
+                h -= 6.f;
+            }
+        }
+    }
 
     /**
     * @brief Convert hue saturation value in red green blue
@@ -242,6 +271,45 @@ public:
     * @param b blue channel [0 ; 65535] (return value)
     */
     static void hsv2rgb (float h, float s, float v, float &r, float &g, float &b);
+
+static inline void hsv2rgbdcp (float h, float s, float v, float &r, float &g, float &b)
+{
+    // special version for dcp which saves 1 division (in caller) and six multiplications (inside this function)
+    int i = h;  // sector 0 to 5, floor() is very slow, and h is always >0
+    float f = h - i; // fractional part of h
+
+    v *= 65535.f;
+    float vs = v * s;
+    float p = v - vs;
+    float q = v - f * vs;
+    float t = p + v - q;
+
+    if (i == 1) {
+        r = q;
+        g = v;
+        b = p;
+    } else if (i == 2) {
+        r = p;
+        g = v;
+        b = t;
+    } else if (i == 3) {
+        r = p;
+        g = q;
+        b = v;
+    } else if (i == 4) {
+        r = t;
+        g = p;
+        b = v;
+    } else if (i == 5) {
+        r = v;
+        g = p;
+        b = q;
+    } else { /*i==(0|6)*/
+        r = v;
+        g = t;
+        b = p;
+    }
+}
     static void hsv2rgb (float h, float s, float v, int &r, int &g, int &b);