/**
* AnimationGIF
* Copyright 2010 by Michael Christen
* First released 20.11.2010 at http://yacy.net
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program in the file lgpl21.txt
* If not, see <http://www.gnu.org/licenses/>.
*/
package org.loklak.graphics;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.awt.image.RenderedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;
import java.util.Random;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.imageio.metadata.IIOInvalidTreeException;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataNode;
import javax.imageio.stream.ImageOutputStream;
import javax.imageio.stream.MemoryCacheImageOutputStream;
import org.eclipse.jetty.util.log.Log;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/*
* for a GIF Image Metadata Format Specification, see:
* http://docs.oracle.com/javase/6/docs/api/javax/imageio/metadata/doc-files/gif_metadata.html
*/
public class AnimationGIF {
private final static String formatName = "javax_imageio_gif_image_1.0";
private final static String aesNodeName = "ApplicationExtensions";
private final static String aeNodeName = "ApplicationExtension";
private final static String gceNodeName = "GraphicControlExtension";
private final static String delayNodeName = "delayTime";
private final static String transparencyFlagNodeName = "transparentColorFlag";
private final static String transparencyIndexNodeName = "transparentColorIndex";
private int counter, loops;
private IIOMetadata iiom;
private ImageWriter writer;
private ImageWriteParam iwp;
private ImageOutputStream ios;
private ByteArrayOutputStream baos;
/**
* create a gif animation producer
* @param loops - number of loops for the animated images. -1 = no loops; 0 = indefinitely loops; else: number of loops
*/
public AnimationGIF(int loops) {
this.counter = 0;
this.loops = loops;
this.ios = null;
this.writer = null;
this.baos = new ByteArrayOutputStream();
Iterator<ImageWriter> writerIterator = ImageIO.getImageWritersByFormatName("GIF");
this.writer = writerIterator.next(); // com.sun.media.imageioimpl.plugins.gif.GIFImageWriter, com.sun.imageio.plugins.gif.GIFImageWriter
this.ios = new MemoryCacheImageOutputStream(baos);
this.writer.setOutput(ios);
this.iwp = writer.getDefaultWriteParam();
}
/**
* add an image to the animation
* @param image the image
* @param delayMillis the frame time of the image in milliseconds
* @param transparencyColorIndex the index of the transparent color, -1 if not used
* @throws IOException
*/
public void addImage(RenderedImage image, int delayMillis, int transparencyColorIndex) throws IOException {
if (this.counter == 0) {
iiom = writer.getDefaultImageMetadata(ImageTypeSpecifier.createFromRenderedImage(image), iwp);
writer.prepareWriteSequence(writer.getDefaultStreamMetadata(iwp));
}
if (this.counter == 0 && loops >= 0) {
IIOMetadata imageMetadata2 = writer.getDefaultImageMetadata(ImageTypeSpecifier.createFromRenderedImage(image), iwp);
try {
setMetadata(imageMetadata2, delayMillis, transparencyColorIndex);
setLoops(imageMetadata2, this.loops);
writer.writeToSequence(new IIOImage(image, null, imageMetadata2), iwp);
} catch (final IIOInvalidTreeException e) {
throw new IOException(e.getMessage());
}
} else try {
setMetadata(iiom, delayMillis, transparencyColorIndex);
writer.writeToSequence(new IIOImage(image, null, iiom), iwp);
} catch (final IIOInvalidTreeException e) {
throw new IOException(e.getMessage());
}
this.counter++;
}
/**
* produce the gif image as byte array
* @return the gif image
*/
public byte[] get() {
if (ios != null) try {
ios.close();
ios = null;
} catch (final IOException e) {}
if (writer != null) {
writer.dispose();
writer = null;
}
return baos.toByteArray();
}
private static void setMetadata(IIOMetadata metaData, int delayMillis, int transparencyColorIndex) throws IIOInvalidTreeException {
Node tree = metaData.getAsTree(formatName);
NodeList nodeList = tree.getChildNodes();
Node gceNode = null;
for (int i = 0, len = nodeList.getLength(); i < len; i++) {
Node curNode = nodeList.item(i);
if (curNode.getNodeName().equals(gceNodeName)) {gceNode = curNode; break;}
}
if (gceNode == null) throw new IIOInvalidTreeException("Invalid image metadata, could not find " + gceNodeName + "node.", null, tree);
Node delayNode = gceNode.getAttributes().getNamedItem(delayNodeName);
if (delayNode == null) {
delayNode = tree.getOwnerDocument().createAttribute(delayNodeName);
gceNode.appendChild(delayNode);
}
delayNode.setNodeValue(Integer.valueOf(delayMillis / 10).toString());
if (transparencyColorIndex >= 0) {
Node transparencyFlagNode = gceNode.getAttributes().getNamedItem(transparencyFlagNodeName);
if (transparencyFlagNode == null) {
transparencyFlagNode = tree.getOwnerDocument().createAttribute(transparencyFlagNodeName);
gceNode.appendChild(transparencyFlagNode);
}
transparencyFlagNode.setNodeValue("TRUE");
Node transparencyIndexNode = gceNode.getAttributes().getNamedItem(transparencyIndexNodeName);
if (transparencyIndexNode == null) {
transparencyIndexNode = tree.getOwnerDocument().createAttribute(transparencyIndexNodeName);
gceNode.appendChild(transparencyIndexNode);
}
transparencyIndexNode.setNodeValue(Integer.valueOf(transparencyColorIndex).toString());
}
metaData.setFromTree(formatName, tree);
}
/**
* set number of loops for this animation
* @param metaData
* @param loops - 0 = loop continuously; 1-65535 = a specific number of loops
* @throws IIOInvalidTreeException
*/
private static void setLoops(IIOMetadata metaData, int loops) throws IIOInvalidTreeException {
Node tree = metaData.getAsTree(formatName);
IIOMetadataNode aes = new IIOMetadataNode(aesNodeName);
IIOMetadataNode ae = new IIOMetadataNode(aeNodeName);
ae.setAttribute("applicationID", "NETSCAPE");
ae.setAttribute("authenticationCode", "2.0");
ae.setUserObject(new byte[]{0x1, (byte) (loops & 0xFF), (byte) ((loops >> 8) & 0xFF)});
aes.appendChild(ae);
tree.appendChild(aes);
metaData.setFromTree(formatName, tree);
}
/**
* test image generator
*/
private static RenderedImage generateTestImage(int width, int height, Random r, double angle) {
BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = img.getGraphics();
g.setColor(Color.white); g.fillRect(0, 0, width, height); g.setColor(Color.BLUE);
int x = width / 2;
int y = height / 2;
int radius = Math.min(x, y);
g.drawLine(x, y, x + (int) (radius * Math.cos(angle)), y + (int) (radius * Math.sin(angle)));
g.drawString("giftest", r.nextInt(width), r.nextInt(height));
return img;
}
public static void main(String[] args) {
System.setProperty("java.awt.headless", "true"); // go into headless awt mode
Random r = new Random(System.currentTimeMillis());
int framescount = 100;
AnimationGIF generator = new AnimationGIF(0);
try {
for (int i = 0; i < framescount; i++) {
generator.addImage(generateTestImage(320, 160, r, i * 2 * Math.PI / framescount), 10, 0);
}
FileOutputStream fos = new FileOutputStream(new File("/tmp/giftest.gif"));
fos.write(generator.get());
fos.close();
} catch (final IOException e) {
Log.getLog().warn(e);
}
}
}