MultistepRescaleOpTest.java

/*
 * Copyright 2013, Morten Nobel-Joergensen
 *
 * License: The BSD 3-Clause License
 * http://opensource.org/licenses/BSD-3-Clause
 */
package com.mortennobel.imagescaling;

import java.awt.RenderingHints;
import java.awt.image.BufferedImage;

import javax.imageio.ImageIO;

import junit.framework.TestCase;

import com.mortennobel.imagescaling.experimental.ImprovedMultistepRescaleOp;

public class MultistepRescaleOpTest extends TestCase {

	protected BufferedImage image;

	/**
	 * Sets up the fixture, for example, open a network connection.
	 * This method is called before a test is executed.
	 */
	@Override
    protected void setUp() throws Exception {
		this.image = ImageIO.read(getClass().getResource("largeimage-thump.jpg"));
	}

	public void testCorrect(){
		final BufferedImage reference = new MultiStepRescaleOp(this.image.getWidth()/4, this.image.getHeight()/4,RenderingHints.VALUE_INTERPOLATION_BILINEAR).filter(this.image, null);
		final BufferedImage result = new ImprovedMultistepRescaleOp(this.image.getWidth()/4, this.image.getHeight()/4,RenderingHints.VALUE_INTERPOLATION_BILINEAR).filter(this.image, null);
		assertEquals(result, reference);
	}

	public void assertEquals(final BufferedImage image1, final BufferedImage image2){
		assertSame(image1.getWidth(), image2.getWidth());
		assertSame(image1.getHeight(), image2.getHeight());

		final int pixels = image1.getWidth()*image2.getHeight();
		int errors = 0;
		for (int x = 0;x<image1.getWidth();x++){
			for (int y=0;y<image1.getHeight();y++){
				final int rgb = image1.getRGB(x,y);
				final int rgb2 = image2.getRGB(x,y);
				if (rgb!=rgb2){
					errors++;
				}
			}
		}
		assertTrue("Pixels : "+pixels+" errors: "+errors, errors==0);
	}
}