/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id$ */
package org.apache.fop.visual;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.RenderedImage;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import org.apache.commons.io.IOUtils;
import org.apache.batik.ext.awt.image.GraphicsUtil;
import org.apache.batik.ext.awt.image.renderable.Filter;
import org.apache.batik.ext.awt.image.spi.ImageTagRegistry;
import org.apache.batik.util.ParsedURL;
/**
* Helper class to visually compare two bitmap images.
* <p>
* This class was created by extracting reusable code from
* org.apache.batik.test.util.ImageCompareText (Apache Batik)
* into this separate class.
* <p>
* TODO Move as utility class to XML Graphics Commons when possible
*/
public final class BitmapComparator {
private BitmapComparator() {
}
/**
* Builds a new BufferedImage that is the difference between the two input images
* @param ref the reference bitmap
* @param gen the newly generated bitmap
* @return the diff bitmap
*/
public static BufferedImage buildDiffImage(BufferedImage ref,
BufferedImage gen) {
BufferedImage diff = new BufferedImage(ref.getWidth(),
ref.getHeight(),
BufferedImage.TYPE_INT_ARGB);
WritableRaster refWR = ref.getRaster();
WritableRaster genWR = gen.getRaster();
WritableRaster dstWR = diff.getRaster();
boolean refPre = ref.isAlphaPremultiplied();
if (!refPre) {
ColorModel cm = ref.getColorModel();
cm = GraphicsUtil.coerceData(refWR, cm, true);
ref = new BufferedImage(cm, refWR, true, null);
}
boolean genPre = gen.isAlphaPremultiplied();
if (!genPre) {
ColorModel cm = gen.getColorModel();
cm = GraphicsUtil.coerceData(genWR, cm, true);
gen = new BufferedImage(cm, genWR, true, null);
}
int w = ref.getWidth();
int h = ref.getHeight();
int [] refPix = null;
int [] genPix = null;
for (int y = 0; y < h; y++) {
refPix = refWR.getPixels(0, y, w, 1, refPix);
genPix = genWR.getPixels(0, y, w, 1, genPix);
for (int i = 0; i < refPix.length; i++) {
// val = ((genPix[i] - refPix[i]) * 5) + 128;
int val = ((refPix[i] - genPix[i]) * 10) + 128;
if ((val & 0xFFFFFF00) != 0) {
if ((val & 0x80000000) != 0) {
val = 0;
} else {
val = 255;
}
}
genPix[i] = val;
}
dstWR.setPixels(0, y, w, 1, genPix);
}
if (!genPre) {
ColorModel cm = gen.getColorModel();
cm = GraphicsUtil.coerceData(genWR, cm, false);
}
if (!refPre) {
ColorModel cm = ref.getColorModel();
cm = GraphicsUtil.coerceData(refWR, cm, false);
}
return diff;
}
/**
* Builds a combined image that places a number of images next to each other for
* manual, visual comparison.
* @param images the array of bitmaps
* @return the combined image
*/
public static BufferedImage buildCompareImage(BufferedImage[] images) {
BufferedImage cmp = new BufferedImage(
images[0].getWidth() * images.length,
images[0].getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = cmp.createGraphics();
g.setPaint(Color.white);
g.fillRect(0, 0, cmp.getWidth(), cmp.getHeight());
int lastWidth = 0;
for (BufferedImage image : images) {
if (lastWidth > 0) {
g.translate(lastWidth, 0);
}
if (image != null) {
g.drawImage(image, 0, 0, null);
lastWidth = image.getWidth();
} else {
lastWidth = 20; //Maybe add a special placeholder image instead later
}
}
g.dispose();
return cmp;
}
/**
* Builds a combined image that places two images next to each other for
* manual, visual comparison.
* @param ref the reference image
* @param gen the actual image
* @return the combined image
*/
public static BufferedImage buildCompareImage(BufferedImage ref,
BufferedImage gen) {
return buildCompareImage(new BufferedImage[] {ref, gen});
}
/**
* Loads an image from a URL
* @param url the URL to the image
* @return the bitmap as BufferedImage
* TODO This method doesn't close the InputStream opened by the URL.
*/
public static BufferedImage getImage(URL url) {
ImageTagRegistry reg = ImageTagRegistry.getRegistry();
Filter filt = reg.readURL(new ParsedURL(url));
if (filt == null) {
return null;
}
RenderedImage red = filt.createDefaultRendering();
if (red == null) {
return null;
}
BufferedImage img = new BufferedImage(red.getWidth(),
red.getHeight(),
BufferedImage.TYPE_INT_ARGB);
red.copyData(img.getRaster());
return img;
}
/**
* Loads an image from a URL
* @param bitmapFile the bitmap file
* @return the bitmap as BufferedImage
*/
public static BufferedImage getImage(File bitmapFile) {
try {
InputStream in = new java.io.FileInputStream(bitmapFile);
try {
in = new java.io.BufferedInputStream(in);
ImageTagRegistry reg = ImageTagRegistry.getRegistry();
Filter filt = reg.readStream(in);
if (filt == null) {
return null;
}
RenderedImage red = filt.createDefaultRendering();
if (red == null) {
return null;
}
BufferedImage img = new BufferedImage(red.getWidth(),
red.getHeight(),
BufferedImage.TYPE_INT_ARGB);
red.copyData(img.getRaster());
return img;
} finally {
IOUtils.closeQuietly(in);
}
} catch (IOException e) {
return null;
}
}
}