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 * Image processing operations for SciJava Ops.
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package org.scijava.ops.image.filter.fftSize;

import java.util.function.BiFunction;

import net.imglib2.Dimensions;

/**
 * Op that calculates FFT fast sizes according to the following logic. If
 * powerOfTwo=true compute next power of 2 If powerOfTwo=false compute next
 * smooth size
 *
 * @author Brian Northan
 * @implNote op names='filter.fftSize'
 */
public class DefaultComputeFFTSize implements
	BiFunction<Dimensions, Boolean, long[][]>
{

	/**
	 * TODO
	 *
	 * @param dimensions
	 * @param powerOfTwo
	 * @return the outputSizes
	 */
	@Override
	public long[][] apply(Dimensions dimensions, Boolean powerOfTwo) {

        var size = new long[2][];
		size[0] = new long[dimensions.numDimensions()];
		size[1] = new long[dimensions.numDimensions()];

		for (var i = 0; i < dimensions.numDimensions(); i++) {
			// real size
			if (powerOfTwo) {
				size[0][i] = NextPowerOfTwo.nextPowerOfTwo(dimensions.dimension(i));
			}
			else {
				size[0][i] = NextSmoothNumber.nextSmooth((int) dimensions.dimension(i));
			}
			// complex size
			if (i == 0) {
				size[1][i] = size[0][i] / 2 + 1;
			}
			else {
				size[1][i] = size[0][i];
			}
		}

		return size;

	}

}
