/*
* 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: PNGRenderer.java 679326 2008-07-24 09:35:34Z vhennebert $ */
package org.apache.fop.render.bitmap;
import java.awt.image.RenderedImage;
import java.io.IOException;
import java.io.OutputStream;
import org.apache.commons.io.IOUtils;
import org.apache.xmlgraphics.image.writer.ImageWriter;
import org.apache.xmlgraphics.image.writer.ImageWriterParams;
import org.apache.xmlgraphics.image.writer.ImageWriterRegistry;
import org.apache.fop.apps.MimeConstants;
import org.apache.fop.area.PageViewport;
import org.apache.fop.render.java2d.Java2DRenderer;
/**
* PNG Renderer This class actually does not render itself, instead it extends
* <code>org.apache.fop.render.java2D.Java2DRenderer</code> and just encode
* rendering results into PNG format using Batik's image codec
*/
public class PNGRenderer extends Java2DRenderer {
/** The MIME type for png-Rendering */
public static final String MIME_TYPE = MimeConstants.MIME_PNG;
/** The file extension expected for PNG files */
private static final String PNG_FILE_EXTENSION = "png";
/** The OutputStream for the first Image */
private OutputStream firstOutputStream;
/** Helper class for generating multiple files */
private MultiFileRenderingUtil multiFileUtil;
/** {@inheritDoc} */
public String getMimeType() {
return MIME_TYPE;
}
/** {@inheritDoc} */
public void startRenderer(OutputStream outputStream) throws IOException {
log.info("rendering areas to PNG");
multiFileUtil = new MultiFileRenderingUtil(PNG_FILE_EXTENSION,
getUserAgent().getOutputFile());
this.firstOutputStream = outputStream;
}
/** {@inheritDoc} */
public void stopRenderer() throws IOException {
super.stopRenderer();
for (int i = 0; i < pageViewportList.size(); i++) {
OutputStream os = getCurrentOutputStream(i);
if (os == null) {
BitmapRendererEventProducer eventProducer
= BitmapRendererEventProducer.Provider.get(
getUserAgent().getEventBroadcaster());
eventProducer.stoppingAfterFirstPageNoFilename(this);
break;
}
try {
// Do the rendering: get the image for this page
PageViewport pv = (PageViewport)pageViewportList.get(i);
RenderedImage image = (RenderedImage)getPageImage(pv);
// Encode this image
if (log.isDebugEnabled()) {
log.debug("Encoding page " + (i + 1));
}
writeImage(os, image);
} finally {
//Only close self-created OutputStreams
if (os != firstOutputStream) {
IOUtils.closeQuietly(os);
}
}
}
}
private void writeImage(OutputStream os, RenderedImage image) throws IOException {
ImageWriterParams params = new ImageWriterParams();
params.setResolution(Math.round(userAgent.getTargetResolution()));
// Encode PNG image
ImageWriter writer = ImageWriterRegistry.getInstance().getWriterFor(getMimeType());
if (writer == null) {
BitmapRendererEventProducer eventProducer
= BitmapRendererEventProducer.Provider.get(
getUserAgent().getEventBroadcaster());
eventProducer.noImageWriterFound(this, getMimeType());
}
if (log.isDebugEnabled()) {
log.debug("Writing image using " + writer.getClass().getName());
}
writer.writeImage(image, os, params);
}
/**
* Returns the OutputStream corresponding to this page
* @param pageNumber 0-based page number
* @return the corresponding OutputStream
* @throws IOException In case of an I/O error
*/
protected OutputStream getCurrentOutputStream(int pageNumber) throws IOException {
if (pageNumber == 0) {
return firstOutputStream;
} else {
return multiFileUtil.createOutputStream(pageNumber);
}
}
}