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diff --git a/quantize/PointProviderLab.java b/quantize/PointProviderLab.java
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+/*
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.ux.material.libmonet.quantize;
+
+import com.google.ux.material.libmonet.utils.ColorUtils;
+
+/**
+ * Provides conversions needed for K-Means quantization. Converting input to points, and converting
+ * the final state of the K-Means algorithm to colors.
+ */
+public final class PointProviderLab implements PointProvider {
+  /**
+   * Convert a color represented in ARGB to a 3-element array of L*a*b* coordinates of the color.
+   */
+  @Override
+  public double[] fromInt(int argb) {
+    double[] lab = ColorUtils.labFromArgb(argb);
+    return new double[] {lab[0], lab[1], lab[2]};
+  }
+
+  /** Convert a 3-element array to a color represented in ARGB. */
+  @Override
+  public int toInt(double[] lab) {
+    return ColorUtils.argbFromLab(lab[0], lab[1], lab[2]);
+  }
+
+  /**
+   * Standard CIE 1976 delta E formula also takes the square root, unneeded here. This method is
+   * used by quantization algorithms to compare distance, and the relative ordering is the same,
+   * with or without a square root.
+   *
+   * <p>This relatively minor optimization is helpful because this method is called at least once
+   * for each pixel in an image.
+   */
+  @Override
+  public double distance(double[] one, double[] two) {
+    double dL = (one[0] - two[0]);
+    double dA = (one[1] - two[1]);
+    double dB = (one[2] - two[2]);
+    return (dL * dL + dA * dA + dB * dB);
+  }
+}