Adds orientation of pdf417 barcode to Result metadata (#1522)

* Adds orientation of pdf417 barcode to Result metadata

Co-authored-by: Jordan Wild <jwild@simplenexus.com>

core/src/main/java/com/google/zxing/common/BitMatrix.java

@@ -286,6 +286,27 @@ public final class BitMatrix implements Cloneable {
     System.arraycopy(row.getBitArray(), 0, bits, y * rowSize, rowSize);
   }
 
+  /**
+   * Modifies this {@code BitMatrix} to represent the same but rotated the given degrees (multiple of 0, 90, 180, 270)
+   */
+  public void rotate(int degrees) {
+    switch (degrees % 360) {
+      case 0:
+        return;
+      case 90:
+        rotate90();
+        return;
+      case 180:
+        rotate180();
+        return;
+      case 270:
+        rotate90();
+        rotate180();
+        return;
+    }
+    throw new IllegalArgumentException("degrees must be a multiple of 0, 90, 180, or 270");
+  }
+
   /**
    * Modifies this {@code BitMatrix} to represent the same but rotated 180 degrees
    */

core/src/main/java/com/google/zxing/pdf417/PDF417Reader.java

@@ -94,6 +94,7 @@ public final class PDF417Reader implements Reader, MultipleBarcodeReader {
       if (pdf417ResultMetadata != null) {
         result.putMetadata(ResultMetadataType.PDF417_EXTRA_METADATA, pdf417ResultMetadata);
       }
+      result.putMetadata(ResultMetadataType.ORIENTATION, detectorResult.getRotation());
       result.putMetadata(ResultMetadataType.SYMBOLOGY_IDENTIFIER, "]L" + decoderResult.getSymbologyModifier());
       results.add(result);
     }

core/src/main/java/com/google/zxing/pdf417/detector/Detector.java

@@ -57,6 +57,7 @@ public final class Detector {
   // ensure we don't miss it.
   private static final int ROW_STEP = 5;
   private static final int BARCODE_MIN_HEIGHT = 10;
+  private static final int[] ROTATIONS = {0, 180, 270, 90};
 
   private Detector() {
   }
@@ -77,20 +78,31 @@ public final class Detector {
     // different binarizers
     //boolean tryHarder = hints != null && hints.containsKey(DecodeHintType.TRY_HARDER);
 
-    BitMatrix bitMatrix = image.getBlackMatrix();
-
-    List<ResultPoint[]> barcodeCoordinates = detect(multiple, bitMatrix);
-    // Try 180, 270, 90 degree rotations, in that order
-    for (int rotate = 0; barcodeCoordinates.isEmpty() && rotate < 3; rotate++) {
-      bitMatrix = bitMatrix.clone();
-      if (rotate != 1) {
-        bitMatrix.rotate180();
-      } else {
-        bitMatrix.rotate90();
+    BitMatrix originalMatrix = image.getBlackMatrix();
+    for (int rotation : ROTATIONS) {
+      BitMatrix bitMatrix = applyRotation(originalMatrix, rotation);
+      List<ResultPoint[]> barcodeCoordinates = detect(multiple, bitMatrix);
+      if (!barcodeCoordinates.isEmpty()) {
+        return new PDF417DetectorResult(bitMatrix, barcodeCoordinates, rotation);
       }
-      barcodeCoordinates = detect(multiple, bitMatrix);
     }
-    return new PDF417DetectorResult(bitMatrix, barcodeCoordinates);
+    return new PDF417DetectorResult(originalMatrix, new ArrayList<>(), 0);
+  }
+
+  /**
+   * Applies a rotation to the supplied BitMatrix.
+   * @param matrix bit matrix to apply rotation to
+   * @param rotation the degrees of rotation to apply
+   * @return BitMatrix with applied rotation
+   */
+  private static BitMatrix applyRotation(BitMatrix matrix, int rotation) {
+    if (rotation % 360 == 0) {
+      return matrix;
+    }
+
+    BitMatrix newMatrix = matrix.clone();
+    newMatrix.rotate(rotation);
+    return newMatrix;
   }
 
   /**

core/src/main/java/com/google/zxing/pdf417/detector/PDF417DetectorResult.java

@@ -28,10 +28,16 @@ public final class PDF417DetectorResult {
 
   private final BitMatrix bits;
   private final List<ResultPoint[]> points;
+  private final int rotation;
 
-  public PDF417DetectorResult(BitMatrix bits, List<ResultPoint[]> points) {
+  public PDF417DetectorResult(BitMatrix bits, List<ResultPoint[]> points, int rotation) {
     this.bits = bits;
     this.points = points;
+    this.rotation = rotation;
+  }
+
+  public PDF417DetectorResult(BitMatrix bits, List<ResultPoint[]> points) {
+    this(bits, points, 0);
   }
 
   public BitMatrix getBits() {
@@ -42,4 +48,8 @@ public final class PDF417DetectorResult {
     return points;
   }
 
+  public int getRotation() {
+    return rotation;
+  }
+
 }