Added QRcode decoding wrapper

Author: dren-dk

README

@@ -0,0 +1,20 @@
+Gear Book: Informal gear management for hackerspaces
+
+The moving parts are:
+
+* labels: The label generator *
+Produces a stak of PDFs that make it easy to print
+the labels needed, each label contains a QR code which links into the
+database and some tags, like "Do Not Hack" and "Borrowed, take extra care".
+
+
+* wiki: The database *
+Unlike more formal systems, the database which holds the list of equipment
+is simply an existing wiki system, in the case of OSAA, it's just media wiki
+with a bunch of infoboxen that make sense to us, YMMV and so on.
+
+* server: Equipment registrator *
+This is a simple web application written in java which uses ZXing to recognize
+QR codes in photos and semi-automagically turn a stream of photos into
+new gear registrations.
+

server/.classpath

@@ -23,5 +23,7 @@
 	<classpathentry kind="lib" path="lib/jetty-distribution-8.0.0.M0/lib/jetty-websocket-8.0.0.M0.jar"/>
 	<classpathentry kind="lib" path="lib/jetty-distribution-8.0.0.M0/lib/jetty-xml-8.0.0.M0.jar"/>
 	<classpathentry kind="lib" path="lib/jetty-distribution-8.0.0.M0/lib/servlet-api-3.0.jar"/>
+	<classpathentry kind="lib" path="lib/zxing-1.6/core/core.jar" sourcepath="lib/zxing-1.6/core/src"/>
+	<classpathentry kind="lib" path="lib/zxing-1.6/javase/javase.jar"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>

server/lib/zxing-1.6/javase/javase.jar

@@ -0,0 +1,44 @@
+package dk.osaa.gb;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.util.Collection;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import org.eclipse.jetty.server.Handler;
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.server.handler.DefaultHandler;
+import org.eclipse.jetty.server.handler.HandlerList;
+import org.eclipse.jetty.server.handler.ResourceHandler;
+
+public class GearBook {
+	static Logger log = Logger.getLogger(GearBook.class.getName());
+
+	public static void main(String[] args) {
+		Server server = new Server(Integer.getInteger("dk.osaa.gb.port", 8000));
+
+		try {
+			ResourceHandler resource_handler = new ResourceHandler();
+			resource_handler.setDirectoriesListed(true);
+			resource_handler.setWelcomeFiles(new String[]{ "index.html" });
+			File root = new File(System.getProperty("dk.osaa.gb.root", "root")).getAbsoluteFile();
+			System.err.println("Serving files out of "+root);
+			resource_handler.setResourceBase(root.getAbsolutePath());
+
+			HandlerList handlers = new HandlerList();
+			handlers.setHandlers(new Handler[] {
+					resource_handler,
+					new NewGearHandler(),
+					new DefaultHandler()
+			});
+			server.setHandler(handlers);
+
+			server.start();
+			server.join();
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+}

server/src/dk/osaa/gb/GearBook.java

@@ -1,4 +1,4 @@
-package gb.osaa.dk;
+package dk.osaa.gb;
 
 import java.io.IOException;
 

server/src/gb/osaa/dk/NewGearHandler.java renamed to server/src/dk/osaa/gb/NewGearHandler.java

@@ -0,0 +1,160 @@
+package dk.osaa.gb;
+
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Hashtable;
+import java.util.Vector;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.imageio.ImageIO;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.BinaryBitmap;
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.LuminanceSource;
+import com.google.zxing.MultiFormatReader;
+import com.google.zxing.Reader;
+import com.google.zxing.ReaderException;
+import com.google.zxing.Result;
+import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
+import com.google.zxing.common.GlobalHistogramBinarizer;
+import com.google.zxing.common.HybridBinarizer;
+import com.google.zxing.multi.GenericMultipleBarcodeReader;
+import com.google.zxing.multi.MultipleBarcodeReader;
+
+/**
+ * Wrapper for ZXing, which allows mortals to use the library.
+ */
+public class QRDecoder {
+	
+	private static Logger log = Logger.getLogger(QRDecoder.class.getName());
+
+	private static final Hashtable<DecodeHintType, Object> HINTS;
+	private static final Hashtable<DecodeHintType, Object> HINTS_PURE;
+
+	static {
+		HINTS = new Hashtable<DecodeHintType, Object>(5);
+		HINTS.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
+		Collection<BarcodeFormat> possibleFormats = new Vector<BarcodeFormat>(17);
+		possibleFormats.add(BarcodeFormat.QR_CODE);
+		HINTS.put(DecodeHintType.POSSIBLE_FORMATS, possibleFormats);
+		HINTS_PURE = new Hashtable<DecodeHintType, Object>(HINTS);
+		HINTS_PURE.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
+	}
+
+	/**
+	 * Simple QR decoding routing, will try very hard to find one or more QR codes in the image and return them.
+	 * @param is The input stream where the image can be read from
+	 * @return The results, might be 0 long.
+	 */
+	public static Collection<Result> decodeImage(InputStream is) { 
+
+		Collection<Result> results = new ArrayList<Result>(1);
+
+		BufferedImage image;
+		try {
+			image = ImageIO.read(is);
+		} catch (Exception e) {
+			log.log(Level.INFO, "Got exception while reading image from strea, perhaps it's corrupt", e);
+			return results;
+		}
+		
+		if (image == null) {
+			log.log(Level.INFO, "bad image");
+			return results;
+		}
+
+		Reader reader = new MultiFormatReader();
+		LuminanceSource source = new BufferedImageLuminanceSource(image);
+		BinaryBitmap bitmap = new BinaryBitmap(new GlobalHistogramBinarizer(source));
+
+		try {
+			// Look for multiple barcodes
+			MultipleBarcodeReader multiReader = new GenericMultipleBarcodeReader(reader);
+			Result[] theResults = multiReader.decodeMultiple(bitmap, HINTS);
+			if (theResults != null) {
+				results.addAll(Arrays.asList(theResults));
+			}
+		} catch (ReaderException re) {
+		}
+
+		if (results.isEmpty()) {
+			try {
+				// Look for pure barcode
+				Result theResult = reader.decode(bitmap, HINTS_PURE);
+				if (theResult != null) {
+					results.add(theResult);
+				}
+			} catch (ReaderException re) {
+			}
+		}
+
+		if (results.isEmpty()) {
+			try {
+				// Look for normal barcode in photo
+				Result theResult = reader.decode(bitmap, HINTS);
+				if (theResult != null) {
+					results.add(theResult);
+				}
+			} catch (ReaderException re) {
+			}
+		}
+
+		if (results.isEmpty()) {
+			try {
+				// Try again with other binarizer
+				BinaryBitmap hybridBitmap = new BinaryBitmap(new HybridBinarizer(source));
+				Result theResult = reader.decode(hybridBitmap, HINTS);
+				if (theResult != null) {
+					results.add(theResult);
+				}
+			} catch (ReaderException re) {
+			}
+		}
+
+		if (results.isEmpty()) {
+			log.fine("Failed to find any barcode in image");
+			return results;
+		}
+
+		if (log.isLoggable(Level.FINE)) {
+			for (Result result : results) {
+				log.fine(result.getText());
+			}
+		}
+		
+		return results;
+	}
+	
+	/**
+	 * Just a small bit of test code, not really suitable for anything. 
+	 * @param args Ignored
+	 */
+	public static void main(String[] args) {
+		
+		File td = new File("/home/ff/projects/osaa/GearBook/testdata");
+		for (File f : td.listFiles()) {
+			
+			log.info("Reading: "+f);
+			try {
+				Collection<Result> results =  QRDecoder.decodeImage(new FileInputStream(f));
+				for (Result r : results) {
+					log.info("Found: "+r);
+				}
+				
+			} catch (FileNotFoundException e) {
+				log.log(Level.SEVERE, "Urgh: "+f, e);
+				continue;
+			}
+			
+		}
+		System.exit(0);
+	}
+}