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diff --git a/src/trace/cielab.h b/src/trace/cielab.h
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+++ b/src/trace/cielab.h
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2005, 2006 by Gerald Friedland, Kristian Jantz and Lars Knipping
+ * Conversion to C++ for Inkscape by Bob Jamison
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+#ifndef INKSCAPE_TRACE_CIELAB_H
+#define INKSCAPE_TRACE_CIELAB_H
+
+#include <cstdint>
+
+namespace Inkscape {
+namespace Trace {
+
+class CieLab
+{
+public:
+    CieLab()
+    {
+        C = 0;
+        L = A = B = 0.0f;
+    }
+
+    /**
+     * Construct this CieLab from an ARGB value
+     */
+    CieLab(uint32_t rgb);
+
+    CieLab(float l, float a, float b)
+    {
+        C = 0;
+        L = l;
+        A = a;
+        B = b;
+    }
+
+    CieLab(CieLab const &other)
+    {
+        C = other.C;
+        L = other.L;
+        A = other.A;
+        B = other.B;
+    }
+
+    CieLab &operator=(CieLab const &other)
+    {
+        C = other.C;
+        L = other.L;
+        A = other.A;
+        B = other.B;
+        return *this;
+    }
+
+    /**
+     * Retrieve a CieLab value via index.
+     */
+    float operator()(unsigned index) const
+    {
+        switch (index) {
+            case 0: return L;
+            case 1: return A;
+            case 2: return B;
+            default: return 0;
+        }
+    }
+
+    void add(CieLab const &other)
+    {
+        C += other.C;
+        L += other.L;
+        A += other.A;
+        B += other.B;
+    }
+
+    void mul(float scale)
+    {
+        L *= scale;
+        A *= scale;
+        B *= scale;
+    }
+
+    /**
+     * Return this CieLab's value converted to an ARGB value
+     */
+    uint32_t toRGB() const;
+
+    /**
+     * Squared Euclidean distance between two colors in CieLab space.
+     */
+    static float diffSq(CieLab const &c1, CieLab const &c2);
+
+    /**
+     * Computes euclidean distance in CieLab space between two colors.
+     */
+    static float diff(CieLab const &c1, CieLab const &c2);
+
+    unsigned C;
+    float L;
+    float A;
+    float B;
+};
+
+} // namespace Trace
+} // namespace Inkscape
+
+#endif // INKSCAPE_TRACE_CIELAB_H