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authorRubbaBoy <[email protected]>2020-07-06 02:33:28 -0400
committerPhil Burk <[email protected]>2020-10-30 11:19:34 -0700
commit46888fae6eb7b1dd386f7af7d101ead99ae61981 (patch)
tree8969bbfd68d2fb5c0d8b86da49ec2eca230a72ab /src/main/java/com/jsyn/data/Spectrum.java
parentc51e92e813dd481603de078f0778e1f75db2ab05 (diff)
Restructured project, added gradle, JUnit, logger, and more
Added Gradle (and removed ant), modernized testing via the JUnit framework, moved standalone examples from the tests directory to a separate module, removed sparsely used Java logger and replaced it with SLF4J. More work could be done, however this is a great start to greatly improving the health of the codebase.
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+/*
+ * Copyright 2013 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;
+
+import com.jsyn.unitgen.SpectralFFT;
+import com.jsyn.unitgen.SpectralIFFT;
+import com.jsyn.unitgen.SpectralProcessor;
+
+/**
+ * Complex spectrum with real and imaginary parts. The frequency associated with each bin of the
+ * spectrum is:
+ *
+ * <pre>
+ * frequency = binIndex * sampleRate / size
+ * </pre>
+ *
+ * Note that the upper half of the spectrum is above the Nyquist frequency. Those frequencies are
+ * mirrored around the Nyquist frequency. Note that this spectral API is experimental and may change
+ * at any time.
+ *
+ * @author Phil Burk (C) 2013 Mobileer Inc
+ * @version 016
+ * @see SpectralFFT
+ * @see SpectralIFFT
+ * @see SpectralProcessor
+ */
+public class Spectrum {
+ private double[] real;
+ private double[] imaginary;
+ public static final int DEFAULT_SIZE_LOG_2 = 9;
+ public static final int DEFAULT_SIZE = 1 << DEFAULT_SIZE_LOG_2;
+
+ public Spectrum() {
+ this(DEFAULT_SIZE);
+ }
+
+ public Spectrum(int size) {
+ setSize(size);
+ }
+
+ public double[] getReal() {
+ return real;
+ }
+
+ public double[] getImaginary() {
+ return imaginary;
+ }
+
+ /**
+ * If you change the size of the spectrum then the real and imaginary arrays will be
+ * reallocated.
+ *
+ * @param size
+ */
+ public void setSize(int size) {
+ if ((real == null) || (real.length != size)) {
+ real = new double[size];
+ imaginary = new double[size];
+ }
+ }
+
+ public int size() {
+ return real.length;
+ }
+
+ /**
+ * Copy this spectrum to another spectrum of the same length.
+ *
+ * @param destination
+ */
+ public void copyTo(Spectrum destination) {
+ assert (size() == destination.size());
+ System.arraycopy(real, 0, destination.real, 0, real.length);
+ System.arraycopy(imaginary, 0, destination.imaginary, 0, imaginary.length);
+ }
+
+ public void clear() {
+ for (int i = 0; i < real.length; i++) {
+ real[i] = 0.0;
+ imaginary[i] = 0.0;
+ }
+ }
+}