| /* |
| |
| 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. |
| |
| */ |
| package org.apache.batik.svggen; |
| |
| import java.awt.Dimension; |
| import java.awt.Graphics2D; |
| import java.awt.Image; |
| import java.awt.image.BufferedImage; |
| import java.awt.image.RenderedImage; |
| import java.awt.image.renderable.RenderableImage; |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| import org.apache.batik.ext.awt.image.spi.ImageWriter; |
| import org.apache.batik.ext.awt.image.spi.ImageWriterRegistry; |
| import org.apache.batik.util.Base64EncoderStream; |
| import org.w3c.dom.Element; |
| |
| /** |
| * This implementation of ImageHandler encodes the input image as |
| * a PNG image first, then encodes the PNG image using Base64 |
| * encoding and uses the result to encoder the image url using |
| * the data protocol. |
| * |
| * @author <a href="mailto:vincent.hardy@eng.sun.com">Vincent Hardy</a> |
| * @version $Id$ |
| * @see org.apache.batik.svggen.SVGGraphics2D |
| * @see org.apache.batik.svggen.ImageHandler |
| */ |
| public class ImageHandlerBase64Encoder extends DefaultImageHandler { |
| /** |
| * Build an <code>ImageHandlerBase64Encoder</code> instance. |
| */ |
| public ImageHandlerBase64Encoder() { |
| super(); |
| } |
| |
| /** |
| * The handler should set the xlink:href tag and the width and |
| * height attributes. |
| */ |
| public void handleHREF(Image image, Element imageElement, |
| SVGGeneratorContext generatorContext) |
| throws SVGGraphics2DIOException { |
| if (image == null) |
| throw new SVGGraphics2DRuntimeException(ERR_IMAGE_NULL); |
| |
| int width = image.getWidth(null); |
| int height = image.getHeight(null); |
| |
| if (width==0 || height==0) { |
| handleEmptyImage(imageElement); |
| } else { |
| if (image instanceof RenderedImage) { |
| handleHREF((RenderedImage)image, imageElement, |
| generatorContext); |
| } else { |
| BufferedImage buf = |
| new BufferedImage(width, height, |
| BufferedImage.TYPE_INT_ARGB); |
| |
| Graphics2D g = buf.createGraphics(); |
| g.drawImage(image, 0, 0, null); |
| g.dispose(); |
| handleHREF((RenderedImage)buf, imageElement, |
| generatorContext); |
| } |
| } |
| } |
| |
| /** |
| * The handler should set the xlink:href tag and the width and |
| * height attributes. |
| */ |
| public void handleHREF(RenderableImage image, Element imageElement, |
| SVGGeneratorContext generatorContext) |
| throws SVGGraphics2DIOException { |
| if (image == null){ |
| throw new SVGGraphics2DRuntimeException(ERR_IMAGE_NULL); |
| } |
| |
| RenderedImage r = image.createDefaultRendering(); |
| if (r == null) { |
| handleEmptyImage(imageElement); |
| } else { |
| handleHREF(r, imageElement, generatorContext); |
| } |
| } |
| |
| protected void handleEmptyImage(Element imageElement) { |
| imageElement.setAttributeNS(XLINK_NAMESPACE_URI, |
| XLINK_HREF_QNAME, DATA_PROTOCOL_PNG_PREFIX); |
| imageElement.setAttributeNS(null, SVG_WIDTH_ATTRIBUTE, "0"); |
| imageElement.setAttributeNS(null, SVG_HEIGHT_ATTRIBUTE, "0"); |
| } |
| |
| /** |
| * This version of handleHREF encodes the input image into a |
| * PNG image whose bytes are then encoded with Base64. The |
| * resulting encoded data is used to set the url on the |
| * input imageElement, using the data: protocol. |
| */ |
| public void handleHREF(RenderedImage image, Element imageElement, |
| SVGGeneratorContext generatorContext) |
| throws SVGGraphics2DIOException { |
| |
| // |
| // Setup Base64Encoder stream to byte array. |
| // |
| ByteArrayOutputStream os = new ByteArrayOutputStream(); |
| Base64EncoderStream b64Encoder = new Base64EncoderStream(os); |
| try { |
| // |
| // Now, encode the input image to the base 64 stream. |
| // |
| encodeImage(image, b64Encoder); |
| |
| // Close the b64 encoder stream (terminates the b64 streams). |
| b64Encoder.close(); |
| } catch (IOException e) { |
| // Should not happen because we are doing in-memory processing |
| throw new SVGGraphics2DIOException(ERR_UNEXPECTED, e); |
| } |
| |
| // |
| // Finally, write out url |
| // |
| imageElement.setAttributeNS(XLINK_NAMESPACE_URI, |
| XLINK_HREF_QNAME, |
| DATA_PROTOCOL_PNG_PREFIX + |
| os.toString()); |
| |
| } |
| |
| public void encodeImage(RenderedImage buf, OutputStream os) |
| throws SVGGraphics2DIOException { |
| try{ |
| ImageWriter writer = ImageWriterRegistry.getInstance() |
| .getWriterFor("image/png"); |
| writer.writeImage(buf, os); |
| } catch(IOException e) { |
| // We are doing in-memory processing. This should not happen. |
| throw new SVGGraphics2DIOException(ERR_UNEXPECTED); |
| } |
| } |
| |
| /** |
| * This method creates a BufferedImage with an alpha channel, as this is |
| * supported by Base64. |
| */ |
| public BufferedImage buildBufferedImage(Dimension size) { |
| return new BufferedImage(size.width, size.height, |
| BufferedImage.TYPE_INT_ARGB); |
| } |
| } |