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/* * 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: ImageLoaderImageIO.java 806473 2009-08-21 09:23:45Z vhennebert $ */ package org.apache.xmlgraphics.image.loader.impl.imageio; import java.awt.Color; import java.awt.color.ICC_ColorSpace; import java.awt.color.ICC_Profile; import java.awt.image.BufferedImage; import java.awt.image.ColorModel; import java.awt.image.ComponentColorModel; import java.awt.image.IndexColorModel; import java.awt.image.Raster; import java.awt.image.RenderedImage; import java.awt.image.WritableRaster; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.HashSet; import java.util.Iterator; import java.util.Locale; import java.util.Map; import java.util.Set; import java.util.StringTokenizer; import java.util.zip.DataFormatException; import java.util.zip.Inflater; import javax.imageio.IIOException; import javax.imageio.ImageIO; import javax.imageio.ImageReadParam; import javax.imageio.ImageReader; import javax.imageio.metadata.IIOMetadata; import javax.imageio.metadata.IIOMetadataFormatImpl; import javax.imageio.metadata.IIOMetadataNode; import javax.imageio.spi.IIOServiceProvider; import javax.imageio.stream.ImageInputStream; import javax.xml.transform.Source; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.w3c.dom.Element; import org.apache.xmlgraphics.image.loader.Image; import org.apache.xmlgraphics.image.loader.ImageException; import org.apache.xmlgraphics.image.loader.ImageFlavor; import org.apache.xmlgraphics.image.loader.ImageInfo; import org.apache.xmlgraphics.image.loader.ImageSessionContext; import org.apache.xmlgraphics.image.loader.impl.AbstractImageLoader; import org.apache.xmlgraphics.image.loader.impl.ImageBuffered; import org.apache.xmlgraphics.image.loader.impl.ImageRendered; import org.apache.xmlgraphics.image.loader.util.ImageUtil; /** * An ImageLoader implementation based on ImageIO for loading bitmap images. */ public class ImageLoaderImageIO extends AbstractImageLoader { /** logger */ protected static Log log = LogFactory.getLog(ImageLoaderImageIO.class); private ImageFlavor targetFlavor; private static final String PNG_METADATA_NODE = "javax_imageio_png_1.0"; private static final String JPEG_METADATA_NODE = "javax_imageio_jpeg_image_1.0"; private static final Set providersIgnoringICC = new HashSet(); /** * Main constructor. * @param targetFlavor the target flavor */ public ImageLoaderImageIO(ImageFlavor targetFlavor) { if (!(ImageFlavor.BUFFERED_IMAGE.equals(targetFlavor) || ImageFlavor.RENDERED_IMAGE.equals(targetFlavor))) { throw new IllegalArgumentException("Unsupported target ImageFlavor: " + targetFlavor); } this.targetFlavor = targetFlavor; } /** {@inheritDoc} */ public ImageFlavor getTargetFlavor() { return this.targetFlavor; } /** {@inheritDoc} */ public Image loadImage(ImageInfo info, Map hints, ImageSessionContext session) throws ImageException, IOException { RenderedImage imageData = null; IIOException firstException = null; IIOMetadata iiometa = (IIOMetadata) info.getCustomObjects().get(ImageIOUtil.IMAGEIO_METADATA); boolean ignoreMetadata = (iiometa != null); boolean providerIgnoresICC = false; Source src = session.needSource(info.getOriginalURI()); ImageInputStream imgStream = ImageUtil.needImageInputStream(src); try { Iterator iter = ImageIO.getImageReaders(imgStream); while (iter.hasNext()) { ImageReader reader = (ImageReader) iter.next(); try { imgStream.mark(); ImageReadParam param = reader.getDefaultReadParam(); reader.setInput(imgStream, false, ignoreMetadata); final int pageIndex = ImageUtil.needPageIndexFromURI(info.getOriginalURI()); try { if (ImageFlavor.BUFFERED_IMAGE.equals(this.targetFlavor)) { imageData = reader.read(pageIndex, param); } else { imageData = reader.read(pageIndex, param); //imageData = reader.readAsRenderedImage(pageIndex, param); //TODO Reenable the above when proper listeners are implemented //to react to late pixel population (so the stream can be closed //properly). } if (iiometa == null) { iiometa = reader.getImageMetadata(pageIndex); } providerIgnoresICC = checkProviderIgnoresICC(reader.getOriginatingProvider()); break; //Quit early, we have the image } catch (IndexOutOfBoundsException indexe) { throw new ImageException("Page does not exist. Invalid image index: " + pageIndex); } catch (IllegalArgumentException iae) { //Some codecs like com.sun.imageio.plugins.wbmp.WBMPImageReader throw //IllegalArgumentExceptions when they have trouble parsing the image. throw new ImageException("Error loading image using ImageIO codec", iae); } catch (IIOException iioe) { if (firstException == null) { firstException = iioe; } else { log.debug("non-first error loading image: " + iioe.getMessage()); } } try { //Try fallback for CMYK images BufferedImage bi = getFallbackBufferedImage(reader, pageIndex, param); imageData = bi; firstException = null; //Clear exception after successful fallback attempt break; } catch (IIOException iioe) { //ignore } imgStream.reset(); } finally { reader.dispose(); } } } finally { ImageUtil.closeQuietly(src); //TODO Some codecs may do late reading. } if (firstException != null) { throw new ImageException("Error while loading image: " + firstException.getMessage(), firstException); } if (imageData == null) { throw new ImageException("No ImageIO ImageReader found ."); } ColorModel cm = imageData.getColorModel(); Color transparentColor = null; if (cm instanceof IndexColorModel) { //transparent color will be extracted later from the image } else { if (providerIgnoresICC && cm instanceof ComponentColorModel) { // Apply ICC Profile to Image by creating a new image with a new // color model. ICC_Profile iccProf = tryToExctractICCProfile(iiometa); if (iccProf != null) { ColorModel cm2 = new ComponentColorModel(new ICC_ColorSpace(iccProf), cm.hasAlpha(), cm.isAlphaPremultiplied(), cm.getTransparency(), cm.getTransferType()); WritableRaster wr = Raster.createWritableRaster(imageData.getSampleModel(), null); imageData.copyData(wr); BufferedImage bi = new BufferedImage(cm2, wr, cm2.isAlphaPremultiplied(), null); imageData = bi; cm = cm2; } } // ImageIOUtil.dumpMetadataToSystemOut(iiometa); // Retrieve the transparent color from the metadata if (iiometa != null && iiometa.isStandardMetadataFormatSupported()) { Element metanode = (Element) iiometa.getAsTree(IIOMetadataFormatImpl.standardMetadataFormatName); Element dim = ImageIOUtil.getChild(metanode, "Transparency"); if (dim != null) { Element child; child = ImageIOUtil.getChild(dim, "TransparentColor"); if (child != null) { String value = child.getAttribute("value"); if (value == null || value.length() == 0) { //ignore } else if (cm.getNumColorComponents() == 1) { int gray = Integer.parseInt(value); transparentColor = new Color(gray, gray, gray); } else { StringTokenizer st = new StringTokenizer(value); transparentColor = new Color(Integer.parseInt(st.nextToken()), Integer.parseInt(st.nextToken()), Integer.parseInt(st.nextToken())); } } } } } if (ImageFlavor.BUFFERED_IMAGE.equals(this.targetFlavor)) { return new ImageBuffered(info, (BufferedImage) imageData, transparentColor); } else { return new ImageRendered(info, imageData, transparentColor); } } /** * Checks if the provider ignores the ICC color profile. This method will * assume providers work correctly, and return false if the provider is * unknown. This ensures backward-compatibility. * * @param provider * the ImageIO Provider * @return true if we know the provider to be broken and ignore ICC * profiles. */ private boolean checkProviderIgnoresICC(IIOServiceProvider provider) { // TODO: This information could be cached. StringBuffer b = new StringBuffer(provider.getDescription(Locale.ENGLISH)); b.append('/').append(provider.getVendorName()); b.append('/').append(provider.getVersion()); if (log.isDebugEnabled()) { log.debug("Image Provider: " + b.toString()); } return ImageLoaderImageIO.providersIgnoringICC.contains(b.toString()); } /** * Extract ICC Profile from ImageIO Metadata. This method currently only * supports PNG and JPEG metadata. * * @param iiometa * The ImageIO Metadata * @return an ICC Profile or null. */ private ICC_Profile tryToExctractICCProfile(IIOMetadata iiometa) { ICC_Profile iccProf = null; String supportedFormats[] = iiometa.getMetadataFormatNames(); for (int i = 0; i < supportedFormats.length; i++) { String format = supportedFormats[i]; Element root = (Element) iiometa.getAsTree(format); if (PNG_METADATA_NODE.equals(format)) { iccProf = this.tryToExctractICCProfileFromPNGMetadataNode(root); } else if (JPEG_METADATA_NODE.equals(format)) { iccProf = this.tryToExctractICCProfileFromJPEGMetadataNode(root); } } return iccProf; } private ICC_Profile tryToExctractICCProfileFromPNGMetadataNode(Element pngNode) { ICC_Profile iccProf = null; Element iccpNode = ImageIOUtil.getChild(pngNode, "iCCP"); if (iccpNode instanceof IIOMetadataNode) { IIOMetadataNode imn = (IIOMetadataNode) iccpNode; byte[] prof = (byte[]) imn.getUserObject(); String comp = imn.getAttribute("compressionMethod"); if ("deflate".equalsIgnoreCase(comp)) { Inflater decompresser = new Inflater(); decompresser.setInput(prof); byte[] result = new byte[100]; ByteArrayOutputStream bos = new ByteArrayOutputStream(); boolean failed = false; while (!decompresser.finished() && !failed) { try { int resultLength = decompresser.inflate(result); bos.write(result, 0, resultLength); if (resultLength == 0) { // this means more data or an external dictionary is // needed. Both of which are not available, so we // fail. log.debug("Failed to deflate ICC Profile"); failed = true; } } catch (DataFormatException e) { log.debug("Failed to deflate ICC Profile", e); failed = true; } } decompresser.end(); try { iccProf = ICC_Profile.getInstance(bos.toByteArray()); } catch (IllegalArgumentException e) { log.debug("Failed to interpret embedded ICC Profile", e); iccProf = null; } } } return iccProf; } private ICC_Profile tryToExctractICCProfileFromJPEGMetadataNode(Element jpgNode) { ICC_Profile iccProf = null; Element jfifNode = ImageIOUtil.getChild(jpgNode, "app0JFIF"); if (jfifNode != null) { Element app2iccNode = ImageIOUtil.getChild(jfifNode, "app2ICC"); if (app2iccNode instanceof IIOMetadataNode) { IIOMetadataNode imn = (IIOMetadataNode) app2iccNode; iccProf = (ICC_Profile) imn.getUserObject(); } } return iccProf; } private BufferedImage getFallbackBufferedImage(ImageReader reader, int pageIndex, ImageReadParam param) throws IOException { //Work-around found at: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4799903 //There are some additional ideas there if someone wants to go further. // Try reading a Raster (no color conversion). Raster raster = reader.readRaster(pageIndex, param); // Arbitrarily select a BufferedImage type. int imageType; switch (raster.getNumBands()) { case 1: imageType = BufferedImage.TYPE_BYTE_GRAY; break; case 3: imageType = BufferedImage.TYPE_3BYTE_BGR; break; case 4: imageType = BufferedImage.TYPE_4BYTE_ABGR; break; default: throw new UnsupportedOperationException(); } // Create a BufferedImage. BufferedImage bi = new BufferedImage(raster.getWidth(), raster.getHeight(), imageType); // Set the image data. bi.getRaster().setRect(raster); return bi; } static { // TODO: This list could be kept in a resource file. providersIgnoringICC.add("Standard PNG image reader/Sun Microsystems, Inc./1.0"); providersIgnoringICC.add("Standard JPEG Image Reader/Sun Microsystems, Inc./0.5"); } }