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diff --git a/src/main/java/org/apache/commons/math3/transform/DstNormalization.java b/src/main/java/org/apache/commons/math3/transform/DstNormalization.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.commons.math3.transform;
+
+/**
+ * This enumeration defines the various types of normalizations that can be applied to discrete sine
+ * transforms (DST). The exact definition of these normalizations is detailed below.
+ *
+ * @see FastSineTransformer
+ * @since 3.0
+ */
+public enum DstNormalization {
+    /**
+     * Should be passed to the constructor of {@link FastSineTransformer} to use the
+     * <em>standard</em> normalization convention. The standard DST-I normalization convention is
+     * defined as follows
+     *
+     * <ul>
+     *   <li>forward transform: y<sub>n</sub> = &sum;<sub>k=0</sub><sup>N-1</sup> x<sub>k</sub>
+     *       sin(&pi; nk / N),
+     *   <li>inverse transform: x<sub>k</sub> = (2 / N) &sum;<sub>n=0</sub><sup>N-1</sup>
+     *       y<sub>n</sub> sin(&pi; nk / N),
+     * </ul>
+     *
+     * where N is the size of the data sample, and x<sub>0</sub> = 0.
+     */
+    STANDARD_DST_I,
+
+    /**
+     * Should be passed to the constructor of {@link FastSineTransformer} to use the
+     * <em>orthogonal</em> normalization convention. The orthogonal DCT-I normalization convention
+     * is defined as follows
+     *
+     * <ul>
+     *   <li>Forward transform: y<sub>n</sub> = &radic;(2 / N) &sum;<sub>k=0</sub><sup>N-1</sup>
+     *       x<sub>k</sub> sin(&pi; nk / N),
+     *   <li>Inverse transform: x<sub>k</sub> = &radic;(2 / N) &sum;<sub>n=0</sub><sup>N-1</sup>
+     *       y<sub>n</sub> sin(&pi; nk / N),
+     * </ul>
+     *
+     * which makes the transform orthogonal. N is the size of the data sample, and x<sub>0</sub> =
+     * 0.
+     */
+    ORTHOGONAL_DST_I
+}