franta-hg@6: /**
franta-hg@6:  * copy-image-resizer
franta-hg@6:  * Copyright © 2014 František Kučera (frantovo.cz)
franta-hg@6:  *
franta-hg@6:  * This program is free software: you can redistribute it and/or modify
franta-hg@6:  * it under the terms of the GNU General Public License as published by
franta-hg@6:  * the Free Software Foundation, either version 3 of the License, or
franta-hg@6:  * (at your option) any later version.
franta-hg@6:  *
franta-hg@6:  * This program is distributed in the hope that it will be useful,
franta-hg@6:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@6:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@6:  * GNU General Public License for more details.
franta-hg@6:  *
franta-hg@6:  * You should have received a copy of the GNU General Public License
franta-hg@6:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@6:  */
franta-hg@6: package cz.frantovo.copyImageResizer;
franta-hg@6: 
franta-hg@6: import java.awt.Graphics2D;
franta-hg@6: import java.awt.image.BufferedImage;
franta-hg@6: import java.io.IOException;
franta-hg@6: import java.io.InputStream;
franta-hg@6: import java.io.OutputStream;
franta-hg@6: import java.util.regex.Pattern;
franta-hg@6: import javax.imageio.ImageIO;
franta-hg@6: 
franta-hg@6: /**
franta-hg@6:  *
franta-hg@6:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@6:  */
franta-hg@6: public class SingleImageResizer {
franta-hg@6: 
franta-hg@6: 	public void resize(InputStream input, OutputStream output, ImageFormat outputFormat) throws ResizeException {
franta-hg@6: 		try {
franta-hg@6: 			BufferedImage image = ImageIO.read(input);
franta-hg@6: 			BufferedImage resized = resize(image, 64, 64, image.getType());
franta-hg@6: 
franta-hg@6: 			ImageIO.write(resized, outputFormat.getFormat(), output);
franta-hg@6: 		} catch (IOException e) {
franta-hg@6: 			throw new ResizeException("Error while resizing image", e);
franta-hg@6: 		}
franta-hg@6: 	}
franta-hg@6: 
franta-hg@6: 	private BufferedImage resize(BufferedImage original, int maxWidth, int maxHeight, int type) {
franta-hg@6: 
franta-hg@6: 		int width;
franta-hg@6: 		int height;
franta-hg@6: 		float aspectRatio = (float) original.getWidth() / (float) original.getHeight();
franta-hg@6: 
franta-hg@6: 		if (aspectRatio > 1) {
franta-hg@6: 			width = maxWidth;
franta-hg@6: 			height = Math.max(Math.round(maxWidth / aspectRatio), 1);
franta-hg@6: 		} else {
franta-hg@6: 			width = Math.max(Math.round(maxHeight * aspectRatio), 1);
franta-hg@6: 			height = maxHeight;
franta-hg@6: 		}
franta-hg@6: 
franta-hg@6: 		BufferedImage resized = new BufferedImage(width, height, type);
franta-hg@6: 		Graphics2D g = resized.createGraphics();
franta-hg@6: 		g.drawImage(original, 0, 0, width, height, null);
franta-hg@6: 		g.dispose();
franta-hg@6: 
franta-hg@6: 		return resized;
franta-hg@6: 	}
franta-hg@6: 
franta-hg@6: 	public static enum ImageFormat {
franta-hg@6: 
franta-hg@6: 		JPEG("jpg", Pattern.compile(".*\\.(jpg|jpeg)$", Pattern.CASE_INSENSITIVE)),
franta-hg@6: 		PNG("png", Pattern.compile(".*\\.png$", Pattern.CASE_INSENSITIVE)),
franta-hg@6: 		GIF("gif", Pattern.compile(".*\\.gif$", Pattern.CASE_INSENSITIVE));
franta-hg@6: 
franta-hg@6: 		private final String format;
franta-hg@6: 		private final Pattern regex;
franta-hg@6: 
franta-hg@6: 		private ImageFormat(String format, Pattern regex) {
franta-hg@6: 			this.format = format;
franta-hg@6: 			this.regex = regex;
franta-hg@6: 		}
franta-hg@6: 
franta-hg@6: 		public String getFormat() {
franta-hg@6: 			return format;
franta-hg@6: 		}
franta-hg@6: 
franta-hg@6: 		public static ImageFormat getMatching(String fileName) {
franta-hg@6: 			for (ImageFormat type : values()) {
franta-hg@6: 				if (type.regex.matcher(fileName).matches()) {
franta-hg@6: 					return type;
franta-hg@6: 				}
franta-hg@6: 			}
franta-hg@6: 			return null;
franta-hg@6: 		}
franta-hg@6: 	}
franta-hg@6: }