001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.image.processing.resize;
031
032import org.openimaj.image.FImage;
033import org.openimaj.image.processor.SinglebandImageProcessor;
034
035/**
036 * Simple bi-linear interpolation to resize images.
037 * 
038 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
039 *
040 */
041public class BilinearInterpolation implements SinglebandImageProcessor<Float, FImage> {
042        protected int width;
043        protected int height;
044        protected float scale;
045        
046        /**
047         * Construct a new bilinear interpolator. The parameters
048         * describe the width and height of the generated image, 
049         * together with the scale that goes FROM the NEW image TO
050         * the ORIGINAL.
051         * 
052         * @param width new width.
053         * @param height new height.
054         * @param scale scaling from new size to original.
055         */
056        public BilinearInterpolation(int width, int height, float scale) {
057                this.width = width;
058                this.height = height;
059                this.scale = scale;
060        }
061        
062        @Override
063        public void processImage(FImage image) {
064                FImage newimage = image.newInstance(width, height);
065                
066                for (int y=0; y<height; y++)
067                        for (int x=0; x<width; x++)
068                                newimage.pixels[y][x] = image.getPixelInterp(x*scale, y*scale);
069                
070                image.internalAssign(newimage);
071        }                               
072}