diff options
Diffstat (limited to 'tests/com/jsyn/util/TestFFT.java')
| -rw-r--r-- | tests/com/jsyn/util/TestFFT.java | 145 |
1 files changed, 127 insertions, 18 deletions
diff --git a/tests/com/jsyn/util/TestFFT.java b/tests/com/jsyn/util/TestFFT.java index f7fcce6..c79157d 100644 --- a/tests/com/jsyn/util/TestFFT.java +++ b/tests/com/jsyn/util/TestFFT.java @@ -4,9 +4,9 @@ * 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. @@ -32,7 +32,7 @@ public class TestFFT extends TestCase { super.tearDown(); } - public void checkSingleSine(int size, int bin) { + public void checkSingleSineDouble(int size, int bin) { double[] ar = new double[size]; double[] ai = new double[size]; double[] magnitudes = new double[size]; @@ -43,9 +43,62 @@ public class TestFFT extends TestCase { FourierMath.transform(1, size, ar, ai); FourierMath.calculateMagnitudes(ar, ai, magnitudes); - assertTrue(magnitudes[bin - 1] < 0.001); - assertTrue(magnitudes[bin] > 0.5); - assertTrue(magnitudes[bin + 1] < 0.001); + assertEquals("magnitude", 0.0, magnitudes[bin-1], 0.000001); + assertEquals("magnitude", amplitude, magnitudes[bin], 0.000001); + assertEquals("magnitude", 0.0, magnitudes[bin+1], 0.000001); + /* + for (int i = 0; i < magnitudes.length; i++) { + System.out.printf("%d = %9.7f\n", i, magnitudes[i]); + } +*/ + + } + + public void checkSingleSineFloat(int size, int bin) { + float[] ar = new float[size]; + float[] ai = new float[size]; + float[] magnitudes = new float[size]; + + double amplitude = 1.0; + addSineWave(size, bin, ar, amplitude); + + FourierMath.transform(1, size, ar, ai); + FourierMath.calculateMagnitudes(ar, ai, magnitudes); + + assertEquals("magnitude", 0.0f, magnitudes[bin-1], 0.000001); + assertEquals("magnitude", amplitude, magnitudes[bin], 0.000001); + assertEquals("magnitude", 0.0f, magnitudes[bin+1], 0.000001); +/* + for (int i = 0; i < magnitudes.length; i++) { + System.out.printf("%d = %9.7f\n", i, magnitudes[i]); + } +*/ + } + + public void checkMultipleSine(int size, int[] bins, double[] amplitudes) { + double[] ar = new double[size]; + double[] ai = new double[size]; + double[] magnitudes = new double[size]; + + for(int i = 0; i<bins.length; i++) { + addSineWave(size, bins[i], ar, amplitudes[i]); + } + + FourierMath.transform(1, size, ar, ai); + FourierMath.calculateMagnitudes(ar, ai, magnitudes); + + for(int bin = 0; bin<size; bin++) { + System.out.printf("%d = %9.7f\n", bin, magnitudes[bin]); + + double amplitude = 0.0; + for(int i = 0; i<bins.length; i++) { + if ((bin == bins[i]) || (bin == (size - bins[i]))) { + amplitude = amplitudes[i]; + break; + } + } + assertEquals("magnitude", amplitude, magnitudes[bin], 0.000001); + } } @@ -54,19 +107,45 @@ public class TestFFT extends TestCase { double phaseIncrement = 2.0 * Math.PI * bin / size; for (int i = 0; i < size; i++) { ar[i] += Math.sin(phase) * amplitude; - // System.out.println( i + " = " + ar[i] ); phase += phaseIncrement; } } + private void addSineWave(int size, int bin, float[] ar, double amplitude) { + double phase = 0.0; + double phaseIncrement = 2.0 * Math.PI * bin / size; + for (int i = 0; i < size; i++) { + ar[i] += (float) (Math.sin(phase) * amplitude); + phase += phaseIncrement; + } + } + + public void testSinglesDouble() { + checkSingleSineDouble(32, 1); + checkSingleSineDouble(32, 4); + checkSingleSineDouble(64, 5); + checkSingleSineDouble(256, 3); + } + + public void testSinglesFloat() { + checkSingleSineFloat(32, 1); + checkSingleSineFloat(32, 4); + checkSingleSineFloat(64, 5); + checkSingleSineFloat(256, 3); + } - public void testSingles() { - checkSingleSine(32, 1); - checkSingleSine(32, 2); - checkSingleSine(64, 5); - checkSingleSine(256, 3); + public void testMultipleSines32() { + int[] bins = { 1, 5 }; + double[] amplitudes = { 1.0, 2.0 }; + checkMultipleSine(32, bins, amplitudes); } - public void checkInverseFFT(int size, int bin) { + public void testMultipleSines64() { + int[] bins = { 2, 4, 7 }; + double[] amplitudes = { 1.0, 0.3, 0.5 }; + checkMultipleSine(64, bins, amplitudes); + } + + public void checkInverseFftDouble(int size, int bin) { double[] ar1 = new double[size]; double[] ai1 = new double[size]; double[] ar2 = new double[size]; @@ -89,10 +168,40 @@ public class TestFFT extends TestCase { } } - public void testInverse() { - checkInverseFFT(32, 1); - checkInverseFFT(32, 2); - checkInverseFFT(128, 17); - checkInverseFFT(512, 23); + public void checkInverseFftFloat(int size, int bin) { + float[] ar1 = new float[size]; + float[] ai1 = new float[size]; + float[] ar2 = new float[size]; + float[] ai2 = new float[size]; + + double amplitude = 1.0; + addSineWave(size, bin, ar1, amplitude); + + // Save a copy of the source. + System.arraycopy(ar1, 0, ar2, 0, size); + System.arraycopy(ai1, 0, ai2, 0, size); + + FourierMath.transform(1, size, ar1, ai1); // FFT + + FourierMath.transform(-1, size, ar1, ai1); // IFFT + + for (int i = 0; i < size; i++) { + assertEquals(ar2[i], ar1[i], 0.00001); + assertEquals(ai2[i], ai1[i], 0.00001); + } + } + + public void testInverseDouble() { + checkInverseFftDouble(32, 1); + checkInverseFftDouble(32, 2); + checkInverseFftDouble(128, 17); + checkInverseFftDouble(512, 23); + } + + public void testInverseFloat() { + checkInverseFftFloat(32, 1); + checkInverseFftFloat(32, 2); + checkInverseFftFloat(128, 17); + checkInverseFftFloat(512, 23); } } |