Mega Code Archive
Writes an image to an output stream as a JPEG file The JPEG quality can be specified in percent
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/*
* JSwiff is an open source Java API for Macromedia Flash file generation
* and manipulation
*
* Copyright (C) 2004-2006 Ralf Terdic (contact@jswiff.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
//package com.jswiff.util;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Iterator;
import java.util.Locale;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.imageio.plugins.jpeg.JPEGImageWriteParam;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.ImageOutputStream;
/**
* Provides utility methods for image processing.
*
* @author <a href="mailto:ralf@terdic.de">Ralf Terdic</a>
*/
public class ImageUtilities {
/**
* Returns the format of an image (as string).
*
* @param stream
* image source stream
*
* @return format stream (e.g. "JPEG")
*
* @throws IOException
* if an I/O error occured
*/
public static String getFormat(InputStream stream) throws IOException {
ImageInputStream iis = ImageIO.createImageInputStream(stream);
Iterator iter = ImageIO.getImageReaders(iis);
if (!iter.hasNext()) {
throw new IOException("Unsupported image format!");
}
ImageReader reader = (ImageReader) iter.next();
iis.close();
return reader.getFormatName();
}
/**
* Loads an image from a stream.
*
* @param stream
* input stream
*
* @return the loaded image
*
* @throws IOException
* if the image could not be loaded
*/
public static BufferedImage loadImage(InputStream stream)
throws IOException {
return ImageIO.read(stream);
}
/**
* Writes an image to an output stream as a JPEG file.
*
* @param image
* image to be written
* @param stream
* target stream
*
* @throws IOException
* if an I/O error occured
*/
public static void saveImageAsJPEG(BufferedImage image, OutputStream stream)
throws IOException {
ImageIO.write(image, "jpg", stream);
}
/**
* Writes an image to an output stream as a JPEG file. The JPEG quality can
* be specified in percent.
*
* @param image
* image to be written
* @param stream
* target stream
* @param qualityPercent
* JPEG quality in percent
*
* @throws IOException
* if an I/O error occured
* @throws IllegalArgumentException
* if qualityPercent not between 0 and 100
*/
public static void saveImageAsJPEG(BufferedImage image,
OutputStream stream, int qualityPercent) throws IOException {
if ((qualityPercent < 0) || (qualityPercent > 100)) {
throw new IllegalArgumentException("Quality out of bounds!");
}
float quality = qualityPercent / 100f;
ImageWriter writer = null;
Iterator iter = ImageIO.getImageWritersByFormatName("jpg");
if (iter.hasNext()) {
writer = (ImageWriter) iter.next();
}
ImageOutputStream ios = ImageIO.createImageOutputStream(stream);
writer.setOutput(ios);
ImageWriteParam iwparam = new JPEGImageWriteParam(Locale.getDefault());
iwparam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
iwparam.setCompressionQuality(quality);
writer.write(null, new IIOImage(image, null, null), iwparam);
ios.flush();
writer.dispose();
ios.close();
}
/**
* Writes an image to an output stream as a PNG file.
*
* @param image
* image to be written
* @param stream
* target stream
*
* @throws IOException
* if an I/O error occured
*/
public static void saveImageAsPNG(BufferedImage image, OutputStream stream)
throws IOException {
ImageIO.write(image, "png", stream);
}
private static BufferedImage convertToARGB(BufferedImage srcImage) {
BufferedImage newImage = new BufferedImage(srcImage.getWidth(null),
srcImage.getHeight(null), BufferedImage.TYPE_INT_ARGB);
Graphics bg = newImage.getGraphics();
bg.drawImage(srcImage, 0, 0, null);
bg.dispose();
return newImage;
}
}
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