Create a proper "filter.fft" function op

elevans · gselzer · commit 3d0b19c19fb2 · 2025-02-10T11:53:15.000-06:00
Running `out = ops.op("filter.fft").arity1().input(img).apply()` returns
a blank image. This is because the wrong image dimensions are being used
for the FFT result. This is an example of when adaptation fails. SciJava
Ops adapts the FFT Op into a function and assumes that the output image
dimensions are the same as the input. Generally this is a safe
assumption, but this is an example where the output image dimensions
are in fact different. This commit adds a new Op that depends on
`FFTMethodsOpF` and returns the FFT result as a ComplexFloatType. This
is consistent with the old imagej-ops usage.
diff --git a/scijava-ops-image/src/main/java/org/scijava/ops/image/filter/fft/FFTMethodsOp.java b/scijava-ops-image/src/main/java/org/scijava/ops/image/filter/fft/FFTMethodsOp.java
@@ -0,0 +1,75 @@
+/*
+ * #%L
+ * ImageJ2 software for multidimensional image processing and analysis.
+ * %%
+ * Copyright (C) 2014 - 2023 ImageJ2 developers.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+package org.scijava.ops.image.filter.fft;
+
+import net.imglib2.RandomAccessibleInterval;
+import net.imglib2.type.numeric.RealType;
+import net.imglib2.type.numeric.complex.ComplexFloatType;
+import org.scijava.function.Functions;
+import org.scijava.ops.spi.Nullable;
+import org.scijava.ops.spi.OpDependency;
+
+/**
+ * Function that uses FFTMethods to perform a forward FFT
+ *
+ * @author Brian Northan
+ * @param <T> TODO Documentation
+ */
+public class FFTMethodsOp<T extends RealType<T>> {
+
+	/**
+	 * Note that if fast is true the input will be extended to the next fast FFT
+	 * size. If false the input will be computed using the original input
+	 * dimensions (if possible). If the input dimensions are not supported by the
+	 * underlying FFT implementation the input will be extended to the nearest
+	 * size that is supported. TODO
+	 *
+	 * @param FFTMethodsOpF dependency to FFTMethodsOpF
+	 * @param input input image
+	 * @param borderSize the size of border to apply in each dimension
+	 * @param fast whether to perform a fast FFT; default true
+	 * @return the output
+	 * @implNote op names='filter.fft', priority='100.'
+	 */
+
+	public static <T extends RealType<T>>
+		RandomAccessibleInterval<ComplexFloatType> run( //
+			@OpDependency(
+				name = "filter.fft") Functions.Arity4<RandomAccessibleInterval<T>, ComplexFloatType, long[], Boolean, RandomAccessibleInterval<ComplexFloatType>> FFTMethodsOpF,
+			final RandomAccessibleInterval<T> input, //
+			@Nullable long[] borderSize, //
+			@Nullable Boolean fast //
+	) {
+
+		return FFTMethodsOpF.apply(input, new ComplexFloatType(), borderSize, fast);
+
+	}
+
+}
diff --git a/scijava-ops-image/src/test/java/org/scijava/ops/image/OpRegressionTest.java b/scijava-ops-image/src/test/java/org/scijava/ops/image/OpRegressionTest.java
@@ -42,7 +42,7 @@ public class OpRegressionTest {
 
 	@Test
 	public void testOpDiscoveryRegression() {
-		long expected = 1964;
+		long expected = 1965;
 		long actual = ops.infos().size();
 		assertEquals(expected, actual);
 	}

Original file line number	Diff line number	Diff line change
`@@ -42,7 +42,7 @@ public class OpRegressionTest {`
`42`	`42`
`43`	`43`	`@Test`
`44`	`44`	`public void testOpDiscoveryRegression() {`
`45`		`- long expected = 1964;`
	`45`	`+ long expected = 1965;`
`46`	`46`	`long actual = ops.infos().size();`
`47`	`47`	`assertEquals(expected, actual);`
`48`	`48`	`}`