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diff --git a/pdf-over-signer/src/main/java/at/asit/pdfover/signer/Emblem.java b/pdf-over-signer/src/main/java/at/asit/pdfover/signer/Emblem.java
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+/*
+ * Copyright 2012 by A-SIT, Secure Information Technology Center Austria
+ *
+ * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
+ * the European Commission - subsequent versions of the EUPL (the "Licence");
+ * You may not use this work except in compliance with the Licence.
+ * You may obtain a copy of the Licence at:
+ * http://joinup.ec.europa.eu/software/page/eupl
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the Licence is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the Licence for the specific language governing permissions and
+ * limitations under the Licence.
+ */
+package at.asit.pdfover.signer;
+
+// Imports
+import at.asit.pdfover.commons.Constants;
+import at.asit.pdfover.commons.utils.ImageUtil;
+
+import java.awt.Graphics2D;
+import java.awt.Image;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Properties;
+
+import javax.imageio.ImageIO;
+
+import org.apache.commons.codec.digest.DigestUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * TODO all of this caching business is a bit of a mess
+ */
+public class Emblem {
+	/**
+	 * SLF4J Logger instance
+	 **/
+	private static final Logger log = LoggerFactory.getLogger(Emblem.class);
+
+	private static final String CACHE_DIR = Constants.CONFIG_DIRECTORY;
+	private static final String CACHE_IMG_FILENAME = ".emblem.png";
+	private static final String CACHE_IMG_FORMAT = "png";
+	private static final String CACHE_PROPS_FILENAME = ".emblem.properties";
+
+	private static final String PROPKEY_ORIG_PATH = "IMG";
+	private static final String PROPKEY_ORIG_DIGEST = "HSH";
+	private static final int MAX_EMBLEM_WIDTH  = 480;
+	private static final int MAX_EMBLEM_HEIGHT = 600;
+
+	private String originalFileName = null;
+	private String originalFileHash = null;
+	private Image image = null; /* image data, if we have it */
+
+	private void lazyLoadImage() {
+		if (this.image != null) return;
+
+		String filename = getCachedFileName();
+		if (this.image != null) return; /* getCachedFileName may have re-generated the cache and populated this.image */
+
+		try {
+			this.image = ImageUtil.readImageWithEXIFRotation(new File(filename));
+		} catch (IOException e) {
+			log.warn("Failed to load Emblem image");
+		}
+	}
+
+	public int getWidth() { if (image == null) lazyLoadImage(); return (image != null) ? image.getWidth(null) : 0; }
+	public int getHeight() { if (image == null) lazyLoadImage(); return (image != null) ? image.getHeight(null) : 0; }
+
+	/**
+	 * Constructor
+	 * @param filename
+	 */
+	public Emblem(String filename) {
+		this.originalFileName = filename;
+	}
+
+	private String getFileHash(String filename) throws IOException {
+		InputStream is = Files.newInputStream(Path.of(filename));
+		return DigestUtils.md5Hex(is);
+	}
+
+	private static BufferedImage reduceImageSizeIfNecessary(BufferedImage img, int maxWidth, int maxHeight) {
+		int oheight = img.getHeight();
+		int owidth = img.getWidth();
+
+		double ratio = (double)owidth/(double)oheight;
+
+		int height = oheight;
+		int width = owidth;
+		if (height > maxHeight) {
+			height = maxHeight;
+			width = (int) (maxHeight * ratio);
+		}
+		if (width > maxWidth) {
+			width = maxWidth;
+			height = (int) (maxWidth / ratio);
+		}
+		BufferedImage result = img;
+		if (width != owidth || height != oheight) {
+			//scale image
+			log.debug("Scaling emblem: " + owidth + "x" + oheight + " to " + width + "x" + height);
+			result = new BufferedImage(width, height, img.getType() == 0 ? BufferedImage.TYPE_INT_ARGB : img.getType());
+			Graphics2D g = result.createGraphics();
+			g.drawImage(img, 0, 0, width, height, null);
+			g.dispose();
+		}
+		return result;
+	}
+
+	/* (non-Javadoc)
+	 * @see at.asit.pdfover.signator.Emblem#getFileName()
+	 */
+	public String getCachedFileName() {
+		String emblemImg = this.originalFileName;
+		String emblemHsh = null;
+		String cachedEmblemFileName = CACHE_DIR + File.separator + CACHE_IMG_FILENAME;
+
+		if (emblemImg == null || !(new File(emblemImg).exists()))
+			return null;
+
+		Properties emblemProps = new Properties();
+		// compare cache, try to load if match
+		try {
+			File cacheProps = new File(CACHE_DIR, CACHE_PROPS_FILENAME);
+			if (cacheProps.exists()) {
+				InputStream in = new FileInputStream(cacheProps);
+				emblemProps.load(in);
+				if (emblemImg.equals(emblemProps.getProperty(PROPKEY_ORIG_PATH))) {
+					emblemHsh = getFileHash(emblemImg);
+					if (emblemHsh.equals(emblemProps.getProperty(PROPKEY_ORIG_DIGEST))) {
+						log.debug("Emblem cache hit: " + cachedEmblemFileName);
+						return cachedEmblemFileName;
+					}
+				}
+			}
+			log.debug("Emblem cache miss");
+		} catch (Exception e) {
+			log.warn("Can't load emblem cache", e);
+		}
+
+		try {
+			// create new cache
+			if (emblemHsh == null)
+				emblemHsh = getFileHash(emblemImg);
+			emblemProps.setProperty(PROPKEY_ORIG_PATH, emblemImg);
+			emblemProps.setProperty(PROPKEY_ORIG_DIGEST, emblemHsh);
+			File imgFile = new File(emblemImg);
+
+			BufferedImage img = ImageUtil.readImageWithEXIFRotation(imgFile);
+			img = reduceImageSizeIfNecessary(img, MAX_EMBLEM_WIDTH, MAX_EMBLEM_HEIGHT);
+
+			File file = new File(CACHE_DIR, CACHE_IMG_FILENAME);
+			ImageIO.write(img, CACHE_IMG_FORMAT, file); // ignore returned boolean
+			this.image = img;
+			OutputStream out = new FileOutputStream(new File(CACHE_DIR, CACHE_PROPS_FILENAME));
+			emblemProps.store(out, null);
+		} catch (IOException e) {
+			log.error("Can't save emblem cache", e);
+			return this.originalFileName;
+		}
+		return cachedEmblemFileName;
+	}
+
+	/**
+	 * Return the original filename
+	 * @return the original filename
+	 */
+	public String getOriginalFileName() {
+		return this.originalFileName;
+	}
+
+	/**
+	 * Return the original filename
+	 * @return the original filename
+	 */
+	public String getOriginalFileHash() {
+		if (this.originalFileHash == null) {
+			if (this.originalFileName == null || !(new File(this.originalFileName).exists())) {
+				this.originalFileHash = "";
+			} else try {
+				this.originalFileHash = getFileHash(this.originalFileName);
+			} catch (IOException e) {
+				log.debug("Error getting file hash", e);
+				this.originalFileHash = "";
+			}
+		}
+		return this.originalFileHash;
+	}
+}