Views.tiles() to tile RAI, implemented via more general Views.interva…

…ls()

src/main/java/net/imglib2/view/FunctionView.java

@@ -0,0 +1,92 @@
+/*-
+ * #%L
+ * ImgLib2: a general-purpose, multidimensional image processing library.
+ * %%
+ * Copyright (C) 2009 - 2021 Tobias Pietzsch, Stephan Preibisch, Stephan Saalfeld,
+ * John Bogovic, Albert Cardona, Barry DeZonia, Christian Dietz, Jan Funke,
+ * Aivar Grislis, Jonathan Hale, Grant Harris, Stefan Helfrich, Mark Hiner,
+ * Martin Horn, Steffen Jaensch, Lee Kamentsky, Larry Lindsey, Melissa Linkert,
+ * Mark Longair, Brian Northan, Nick Perry, Curtis Rueden, Johannes Schindelin,
+ * Jean-Yves Tinevez and Michael Zinsmaier.
+ * %%
+ * 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 net.imglib2.view;
+
+import java.util.function.Function;
+
+import net.imglib2.Interval;
+import net.imglib2.RandomAccess;
+import net.imglib2.RandomAccessible;
+import net.imglib2.converter.AbstractConvertedRandomAccess;
+
+class FunctionView< A, B > implements RandomAccessible< B >
+{
+	final protected RandomAccessible< A > source;
+
+	private final Function< A, B > function;
+
+	class FunctionRandomAccess extends AbstractConvertedRandomAccess< A, B >
+	{
+		FunctionRandomAccess( final RandomAccess< A > source )
+		{
+			super( source );
+		}
+
+		@Override
+		public B get()
+		{
+			return function.apply( source.get() );
+		}
+
+		@Override
+		public FunctionRandomAccess copy()
+		{
+			return new FunctionRandomAccess( this.source );
+		}
+	}
+
+	public FunctionView( final RandomAccessible< A > source, final Function< A, B > function )
+	{
+		this.source = source;
+		this.function = function;
+	}
+
+	@Override
+	public int numDimensions()
+	{
+		return source.numDimensions();
+	}
+
+	@Override
+	public RandomAccess< B > randomAccess()
+	{
+		return new FunctionRandomAccess( source.randomAccess() );
+	}
+
+	@Override
+	public RandomAccess< B > randomAccess( final Interval interval )
+	{
+		return new FunctionRandomAccess( source.randomAccess( interval ) );
+	}
+}

src/main/java/net/imglib2/view/Views.java

@@ -69,6 +69,7 @@
 import net.imglib2.type.numeric.IntegerType;
 import net.imglib2.type.numeric.NumericType;
 import net.imglib2.type.numeric.RealType;
+import net.imglib2.util.Grid;
 import net.imglib2.util.Intervals;
 import net.imglib2.util.Pair;
 import net.imglib2.util.Util;
@@ -399,6 +400,68 @@ public static < T > IntervalView< T > interval( final RandomAccessible< T > rand
 		return new IntervalView<>( randomAccessible, interval );
 	}
 
+	/**
+	 * Given a RandomAccessible {@code img}, and a RandomAccessible of Intervals
+	 * {@code intervals}, return a RandomAccessible of
+	 * {@link #interval(RandomAccessible, Interval) interval}s on {@code img}.
+	 * <p>
+	 * For example, if {@code intervals} contains intervals that tile the
+	 * interval of an image, this method returns a RandomAccessible of the tiles
+	 * of that image.
+	 */
+	public static < T > RandomAccessible< RandomAccessibleInterval< T > > intervals( final RandomAccessible< T > img, final RandomAccessible< ? extends Interval > intervals )
+	{
+		return new FunctionView<>( intervals, interval -> Views.interval( img, interval ) );
+	}
+
+	/**
+	 * Given a RandomAccessible {@code img}, and a RandomAccessibleInterval of
+	 * intervals {@code intervals}, return a RandomAccessibleInterval of
+	 * {@link #interval(RandomAccessible, Interval) interval}s on {@code img}.
+	 * <p>
+	 * For example, if {@code intervals} contains intervals that tile the
+	 * interval of an image, this method returns a RandomAccessible of the tiles
+	 * of that image.
+	 */
+	public static < T > RandomAccessibleInterval< RandomAccessibleInterval< T > > intervals( final RandomAccessible< T > img, final RandomAccessibleInterval< ? extends Interval > intervals )
+	{
+		return Views.interval( intervals( img, ( RandomAccessible< ? extends Interval > ) intervals ), intervals );
+	}
+
+	/**
+	 * Split the {@code source} image into blocks of the given {@code tileSize}.
+	 *
+	 * @param tileSize
+	 *     size of a "standard" block (blocks at the border may be truncated).
+	 *     If {@code tileSize.length} doesn't match the number of {@code source}
+	 *     dimensions, it is truncated or extended with 1s.
+	 */
+	public static < T > RandomAccessibleInterval< RandomAccessibleInterval< T > > tiles( final RandomAccessibleInterval< T > source, final long... tileSize )
+	{
+		long[] b = tileSize;
+		if ( tileSize.length != source.numDimensions() )
+		{
+			b = Arrays.copyOf( tileSize, source.numDimensions() );
+			if ( b.length > tileSize.length )
+				Arrays.fill( b, tileSize.length, b.length, 1 );
+		}
+		final Grid grid = new Grid( source.dimensionsAsLongArray(), b );
+		return intervals( source, grid.cellIntervals() );
+	}
+
+	/**
+	 * Split the {@code source} image into blocks of the given {@code tileSize}.
+	 *
+	 * @param tileSize
+	 *     size of a "standard" block (blocks at the border may be truncated).
+	 *     If {@code tileSize.length} doesn't match the number of {@code source}
+	 *     dimensions, it is truncated or extended with 1s.
+	 */
+	public static < T > RandomAccessibleInterval< RandomAccessibleInterval< T > > tiles( final RandomAccessibleInterval< T > source, final int... tileSize )
+	{
+		return tiles( source, Util.int2long( tileSize ) );
+	}
+
 	/**
 	 * Create view that is rotated by 90 degrees. The rotation is specified by
 	 * the fromAxis and toAxis arguments.