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

import net.imglib2.RandomAccessibleInterval;
import net.imglib2.algorithm.fft2.FFTMethods;
import net.imglib2.type.numeric.ComplexType;
import net.imglib2.type.numeric.RealType;

import org.scijava.function.Computers;

/**
 * Forward FFT computer that operates on an RAI and wraps FFTMethods. The input
 * and output size must conform to a supported FFT size. Use
 * {@link org.scijava.ops.image.filter.fftSize.ComputeFFTSize} to calculate the
 * supported FFT size.
 *
 * @author Brian Northan
 * @param <T>
 * @param <C>
 * @implNote op names='filter.fft', priority='0.'
 */
public class FFTMethodsOpC<T extends RealType<T>, C extends ComplexType<C>>
	implements
	Computers.Arity1<RandomAccessibleInterval<T>, RandomAccessibleInterval<C>>
{

	/**
	 * Computes an ND FFT using FFTMethods
	 */
	/**
	 * TODO
	 *
	 * @param input
	 * @param output
	 */
	@Override
	public void compute(final RandomAccessibleInterval<T> input,
		final RandomAccessibleInterval<C> output)
	{

		// perform a real to complex FFT in the first dimension
		FFTMethods.realToComplex(input, output, 0, false);

		// loop and perform complex to complex FFT in the remaining dimensions
		for (var d = 1; d < input.numDimensions(); d++)
			FFTMethods.complexToComplex(output, d, true, false);
	}

}
