Try to support data: URIs

git-svn-id: https://zxing.googlecode.com/svn/trunk@2682 59b500cc-1b3d-0410-9834-0bbf25fbcc57

javase/src/com/google/zxing/client/j2se/DecodeWorker.java

@@ -137,16 +137,7 @@ final class DecodeWorker implements Callable<Integer> {
   }
 
   private Result decode(URI uri, Map<DecodeHintType,?> hints) throws IOException {
-    BufferedImage image;
-    try {
-      image = ImageIO.read(uri.toURL());
-    } catch (IllegalArgumentException ignored) {
-      throw new FileNotFoundException("Resource not found: " + uri);
-    }
-    if (image == null) {
-      System.err.println(uri.toString() + ": Could not load image");
-      return null;
-    }
+    BufferedImage image = ImageReader.readImage(uri);
     try {
       LuminanceSource source;
       if (config.getCrop() == null) {
@@ -183,16 +174,7 @@ final class DecodeWorker implements Callable<Integer> {
   }
 
   private Result[] decodeMulti(URI uri, Map<DecodeHintType,?> hints) throws IOException {
-    BufferedImage image;
-    try {
-      image = ImageIO.read(uri.toURL());
-    } catch (IllegalArgumentException ignored) {
-      throw new FileNotFoundException("Resource not found: " + uri);
-    }
-    if (image == null) {
-      System.err.println(uri.toString() + ": Could not load image");
-      return null;
-    }
+    BufferedImage image = ImageReader.readImage(uri);
     try {
       LuminanceSource source;
       if (config.getCrop() == null) {

javase/src/com/google/zxing/client/j2se/GUIRunner.java

@@ -87,13 +87,10 @@ public final class GUIRunner extends JFrame {
   private static String getDecodeText(File file) {
     BufferedImage image;
     try {
-      image = ImageIO.read(file);
+      image = ImageReader.readImage(file);
     } catch (IOException ioe) {
       return ioe.toString();
     }
-    if (image == null) {
-      return "Could not decode image";
-    }
     LuminanceSource source = new BufferedImageLuminanceSource(image);
     BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
     Result result;

javase/src/com/google/zxing/client/j2se/ImageReader.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2013 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.client.j2se;
+
+import javax.imageio.ImageIO;
+import javax.xml.bind.DatatypeConverter;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.net.URI;
+import java.net.URLDecoder;
+
+/**
+ * Encapsulates reading URIs as images.
+ * 
+ * @author Sean Owen
+ */
+public final class ImageReader {
+
+  private static final String BASE64TOKEN = "base64,";
+  
+  private ImageReader() {
+  }
+
+  public static BufferedImage readImage(URI uri) throws IOException {
+    if ("data".equals(uri.getScheme())) {
+      return readDataURIImage(uri);
+    }
+    BufferedImage result;
+    try {
+      result = ImageIO.read(uri.toURL());
+    } catch (IllegalArgumentException iae) {
+      throw new IOException("Resource not found: " + uri, iae);
+    }
+    if (result == null) {
+      throw new IOException("Could not load " + uri);
+    }
+    return result;
+  }
+  
+  public static BufferedImage readDataURIImage(URI uri) throws IOException {
+    String uriString = uri.toString();
+    if (!uriString.startsWith("data:image/")) {
+      throw new IOException("Unsupported data URI MIME type");
+    }
+    int base64Start = uriString.indexOf(BASE64TOKEN);
+    if (base64Start < 0) {
+      throw new IOException("Unsupported data URI encoding");
+    }
+    String base64DataEncoded = uriString.substring(base64Start + BASE64TOKEN.length());
+    String base64Data = URLDecoder.decode(base64DataEncoded, "UTF-8");
+    byte[] imageBytes = DatatypeConverter.parseBase64Binary(base64Data);
+    return ImageIO.read(new ByteArrayInputStream(imageBytes));
+  }
+  
+  public static BufferedImage readImage(File file) throws IOException {
+    return readImage(file.toURI());
+  }
+  
+}

zxingorg/src/com/google/zxing/web/DecodeServlet.java

@@ -28,6 +28,7 @@ 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.client.j2se.ImageReader;
 import com.google.zxing.common.GlobalHistogramBinarizer;
 import com.google.zxing.common.HybridBinarizer;
 
@@ -126,13 +127,30 @@ public final class DecodeServlet extends HttpServlet {
       imageURIString = "http://" + imageURIString;
     }
 
-    URL imageURL;
+    URI imageURI;
     try {
-      imageURL = new URI(imageURIString).toURL();
+      imageURI = new URI(imageURIString);
     } catch (URISyntaxException ignored) {
       log.info("URI was not valid: " + imageURIString);
       response.sendRedirect("badurl.jspx");
       return;
+    }
+    
+    // Shortcut for data URI
+    if ("data".equals(imageURI.getScheme())) {
+      try {
+        BufferedImage image = ImageReader.readDataURIImage(imageURI);
+        processImage(image, request, response);
+      } catch (IOException ioe) {
+        log.info(ioe.toString());
+        response.sendRedirect("badurl.jspx");
+        return;
+      }
+    }
+    
+    URL imageURL;    
+    try {
+      imageURL = imageURI.toURL();
     } catch (MalformedURLException ignored) {
       log.info("URI was not valid: " + imageURIString);
       response.sendRedirect("badurl.jspx");
@@ -290,6 +308,13 @@ public final class DecodeServlet extends HttpServlet {
       return;
     }
     
+    processImage(image, request, response);
+  }
+  
+  private static void processImage(BufferedImage image,
+                                   ServletRequest request,
+                                   HttpServletResponse response) throws IOException, ServletException {
+
     Reader reader = new MultiFormatReader();
     LuminanceSource source = new BufferedImageLuminanceSource(image);
     BinaryBitmap bitmap = new BinaryBitmap(new GlobalHistogramBinarizer(source));