Added result metadata mechanism: now, reports orientation for 1D barcodes if it's not an upright orientation

git-svn-id: https://zxing.googlecode.com/svn/trunk@281 59b500cc-1b3d-0410-9834-0bbf25fbcc57

core/src/com/google/zxing/Result.java

@@ -16,6 +16,8 @@
 
 package com.google.zxing;
 
+import java.util.Hashtable;
+
 /**
  * <p>Encapsulates the result of decoding a barcode within an image.</p>
  *
@@ -27,12 +29,17 @@ public final class Result {
   private final byte[] rawBytes;
   private final ResultPoint[] resultPoints;
   private final BarcodeFormat format;
+  private Hashtable resultMetadata;
 
-  public Result(String text, byte[] rawBytes, ResultPoint[] resultPoints, BarcodeFormat format) {
+  public Result(String text,
+                byte[] rawBytes,
+                ResultPoint[] resultPoints,
+                BarcodeFormat format) {
     this.text = text;
     this.rawBytes = rawBytes;
     this.resultPoints = resultPoints;
     this.format = format;
+    this.resultMetadata = null;
   }
 
   /**
@@ -65,4 +72,19 @@ public final class Result {
     return format;
   }
 
+  /**
+   * @return {@link Hashtable} mapping {@link ResultMetadataType} keys to values. May be <code>null</code>.
+   *  This contains optional metadata about what was detected about the barcode, like orientation.
+   */
+  public Hashtable getResultMetadata() {
+    return resultMetadata;
+  }
+
+  public void putMetadata(ResultMetadataType type, Object value) {
+    if (resultMetadata == null) {
+      resultMetadata = new Hashtable(3);
+    }
+    resultMetadata.put(type, value);
+  }
+
 }

core/src/com/google/zxing/ResultMetadataType.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2008 Google Inc.
+ *
+ * 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;
+
+/**
+ * Represents some type of metadata about the result of the decoding that the decoder
+ * wishes to communicate back to the caller.
+ *
+ * @author srowen@google.com (Sean Owen)
+ */
+public final class ResultMetadataType {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  /**
+   * Unspecified, application-specific metadata. Maps to an unspecified {@link Object}.
+   */
+  public static final ResultMetadataType OTHER = new ResultMetadataType();
+
+  /**
+   * Denotes the likely approximate orientation of the barcode in the image. This value
+   * is given as degrees rotated clockwise from the normal, upright orientation.
+   * For example a 1D barcode which was found by reading top-to-bottom would be
+   * said to have orientation "90". This key maps to an {@link Integer} whose
+   * value is in the range [0,360).
+   */
+  public static final ResultMetadataType ORIENTATION = new ResultMetadataType();
+
+  private ResultMetadataType() {
+  }
+
+}

core/src/com/google/zxing/oned/AbstractOneDReader.java

@@ -21,6 +21,7 @@ import com.google.zxing.DecodeHintType;
 import com.google.zxing.MonochromeBitmapSource;
 import com.google.zxing.ReaderException;
 import com.google.zxing.Result;
+import com.google.zxing.ResultMetadataType;
 import com.google.zxing.common.BitArray;
 
 import java.util.Hashtable;
@@ -45,7 +46,16 @@ public abstract class AbstractOneDReader implements OneDReader {
     } catch (ReaderException re) {
       if (tryHarder && image.isRotateSupported()) {
         MonochromeBitmapSource rotatedImage = image.rotateCounterClockwise();
-        return doDecode(rotatedImage, hints, tryHarder);        
+        Result result = doDecode(rotatedImage, hints, tryHarder);
+        // Record that we found it rotated 90 degrees CCW / 270 degrees CW
+        Hashtable metadata = result.getResultMetadata();
+        int orientation = 270;
+        if (metadata != null && metadata.containsKey(ResultMetadataType.ORIENTATION)) {
+          // But if we found it reversed in doDecode(), add in that result here:
+          orientation = (orientation + ((Integer) metadata.get(ResultMetadataType.ORIENTATION)).intValue()) % 360;
+        }
+        result.putMetadata(ResultMetadataType.ORIENTATION, new Integer(orientation));
+        return result;
       } else {
         throw re;
       }
@@ -108,6 +118,8 @@ public abstract class AbstractOneDReader implements OneDReader {
             if (barcodesToSkip > 0) { // See if we should skip and keep looking
               barcodesToSkip--;
             } else {
+              // Found it, but upside-down:
+              result.putMetadata(ResultMetadataType.ORIENTATION, new Integer(180));
               return result;
             }
           } catch (ReaderException re2) {