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Diffstat (limited to 'src/main/java/com/jsyn/data/HammingWindow.java')
-rw-r--r-- | src/main/java/com/jsyn/data/HammingWindow.java | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/src/main/java/com/jsyn/data/HammingWindow.java b/src/main/java/com/jsyn/data/HammingWindow.java new file mode 100644 index 0000000..d8e1238 --- /dev/null +++ b/src/main/java/com/jsyn/data/HammingWindow.java @@ -0,0 +1,41 @@ +/* + * Copyright 2009 Phil Burk, Mobileer Inc + * + * 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.jsyn.data; + +public class HammingWindow implements SpectralWindow { + private double[] data; + + /** Construct a generalized Hamming Window */ + public HammingWindow(int length, double alpha, double beta) { + data = new double[length]; + double scaler = 2.0 * Math.PI / (length - 1); + for (int i = 0; i < length; i++) { + data[i] = alpha - (beta * (Math.cos(i * scaler))); + } + } + + /** Traditional Hamming Window with alpha = 25/46 and beta = 21/46 */ + public HammingWindow(int length) { + this(length, 25.0 / 46.0, 21.0 / 46.0); + } + + @Override + public double get(int index) { + return data[index]; + } + +} |