| /* |
| * 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.xmlgraphics.image.loader.impl.imageio; |
| |
| import javax.imageio.metadata.IIOMetadata; |
| import javax.imageio.metadata.IIOMetadataFormatImpl; |
| import javax.xml.transform.OutputKeys; |
| import javax.xml.transform.Result; |
| import javax.xml.transform.Source; |
| import javax.xml.transform.Transformer; |
| import javax.xml.transform.TransformerFactory; |
| import javax.xml.transform.dom.DOMSource; |
| import javax.xml.transform.stream.StreamResult; |
| |
| import org.w3c.dom.Element; |
| import org.w3c.dom.Node; |
| import org.w3c.dom.NodeList; |
| |
| import org.apache.xmlgraphics.image.loader.ImageSize; |
| import org.apache.xmlgraphics.util.UnitConv; |
| |
| /** |
| * Helper and convenience methods for ImageIO. |
| */ |
| public class ImageIOUtil { |
| |
| /** Key for ImageInfo's custom objects to embed the ImageIO metadata */ |
| public static final Object IMAGEIO_METADATA = IIOMetadata.class; |
| |
| /** |
| * Extracts the resolution information from the standard ImageIO metadata. |
| * @param iiometa the metadata provided by ImageIO |
| * @param size the image size object |
| */ |
| public static void extractResolution(IIOMetadata iiometa, ImageSize size) { |
| if (iiometa != null && iiometa.isStandardMetadataFormatSupported()) { |
| Element metanode = (Element)iiometa.getAsTree( |
| IIOMetadataFormatImpl.standardMetadataFormatName); |
| Element dim = getChild(metanode, "Dimension"); |
| if (dim != null) { |
| Element child; |
| double dpiHorz = size.getDpiHorizontal(); |
| double dpiVert = size.getDpiVertical(); |
| child = getChild(dim, "HorizontalPixelSize"); |
| if (child != null) { |
| dpiHorz = UnitConv.IN2MM |
| / Float.parseFloat(child.getAttribute("value")); |
| } |
| child = getChild(dim, "VerticalPixelSize"); |
| if (child != null) { |
| dpiVert = UnitConv.IN2MM |
| / Float.parseFloat(child.getAttribute("value")); |
| } |
| size.setResolution(dpiHorz, dpiVert); |
| size.calcSizeFromPixels(); |
| } |
| } |
| } |
| |
| /** |
| * Returns a child element of another element or null if there's no such child. |
| * @param el the parent element |
| * @param name the name of the requested child |
| * @return the child or null if there's no such child |
| */ |
| public static Element getChild(Element el, String name) { |
| NodeList nodes = el.getElementsByTagName(name); |
| if (nodes.getLength() > 0) { |
| return (Element)nodes.item(0); |
| } else { |
| return null; |
| } |
| } |
| |
| /** |
| * Dumps the content of an IIOMetadata instance to System.out. |
| * @param iiometa the metadata |
| */ |
| public static void dumpMetadataToSystemOut(IIOMetadata iiometa) { |
| String[] metanames = iiometa.getMetadataFormatNames(); |
| for (int j = 0; j < metanames.length; j++) { |
| System.out.println("--->" + metanames[j]); |
| dumpNodeToSystemOut(iiometa.getAsTree(metanames[j])); |
| } |
| } |
| |
| /** |
| * Serializes a W3C DOM node to a String and dumps it to System.out. |
| * @param node a W3C DOM node |
| */ |
| private static void dumpNodeToSystemOut(Node node) { |
| try { |
| Transformer trans = TransformerFactory.newInstance().newTransformer(); |
| trans.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes"); |
| trans.setOutputProperty(OutputKeys.INDENT, "yes"); |
| Source src = new DOMSource(node); |
| Result res = new StreamResult(System.out); |
| trans.transform(src, res); |
| } catch (Exception e) { |
| e.printStackTrace(); |
| } |
| } |
| |
| } |