X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=core%2Fsrc%2Fcom%2Fgoogle%2Fzxing%2Fqrcode%2Fdetector%2FAlignmentPatternFinder.java;h=f9f531cf4edfad8a59eb3e03ccfe0a30af0e1e55;hb=61db77fd4960c475243bfb49cc3b6877aef5d8de;hp=e68d3a185ca0bedecabae90ba49a554823564046;hpb=6980903e85309b4f167d21206d86b467cc6ef4f9;p=zxing.git

diff --git a/core/src/com/google/zxing/qrcode/detector/AlignmentPatternFinder.java b/core/src/com/google/zxing/qrcode/detector/AlignmentPatternFinder.java
index e68d3a18..f9f531cf 100644
--- a/core/src/com/google/zxing/qrcode/detector/AlignmentPatternFinder.java
+++ b/core/src/com/google/zxing/qrcode/detector/AlignmentPatternFinder.java
@@ -94,14 +94,14 @@ final class AlignmentPatternFinder {
       stateCount[0] = 0;
       stateCount[1] = 0;
       stateCount[2] = 0;
-      int currentState = 0;
       int j = startX;
       // Burn off leading white pixels before anything else; if we start in the middle of
       // a white run, it doesn't make sense to count its length, since we don't know if the
       // white run continued to the left of the start point
-      while (!luminanceRow.get(j - startX) && j < maxJ) {
+      while (j < maxJ && !luminanceRow.get(j - startX)) {
         j++;
       }
+      int currentState = 0;
       while (j < maxJ) {
         if (luminanceRow.get(j - startX)) {
           // Black pixel
@@ -160,11 +160,11 @@ final class AlignmentPatternFinder {
   /**
    * @param stateCount count of black/white/black pixels just read
    * @return true iff the proportions of the counts is close enough to the 1/1/1 ratios
-   *  used by alignment patterns to be considered a match
+   *         used by alignment patterns to be considered a match
    */
   private boolean foundPatternCross(int[] stateCount) {
     float moduleSize = this.moduleSize;
-    float maxVariance = moduleSize / 2.5f;
+    float maxVariance = moduleSize / 2.0f;
     for (int i = 0; i < 3; i++) {
       if (Math.abs(moduleSize - stateCount[i]) >= maxVariance) {
         return false;
@@ -181,10 +181,10 @@ final class AlignmentPatternFinder {
    * @param startI row where an alignment pattern was detected
    * @param centerJ center of the section that appears to cross an alignment pattern
    * @param maxCount maximum reasonable number of modules that should be
-   *  observed in any reading state, based on the results of the horizontal scan
+   * observed in any reading state, based on the results of the horizontal scan
    * @return vertical center of alignment pattern, or {@link Float#NaN} if not found
    */
-  private float crossCheckVertical(int startI, int centerJ, int maxCount) {
+  private float crossCheckVertical(int startI, int centerJ, int maxCount, int originalStateCountTotal) {
     MonochromeBitmapSource image = this.image;
 
     int maxI = image.getHeight();
@@ -225,6 +225,11 @@ final class AlignmentPatternFinder {
       return Float.NaN;
     }
 
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
+    if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= originalStateCountTotal) {
+      return Float.NaN;
+    }
+
     return foundPatternCross(stateCount) ? centerFromEnd(stateCount, i) : Float.NaN;
   }
 
@@ -240,8 +245,9 @@ final class AlignmentPatternFinder {
    * @return {@link AlignmentPattern} if we have found the same pattern twice, or null if not
    */
   private AlignmentPattern handlePossibleCenter(int[] stateCount, int i, int j) {
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
     float centerJ = centerFromEnd(stateCount, j);
-    float centerI = crossCheckVertical(i, (int) centerJ, 2 * stateCount[1]);
+    float centerI = crossCheckVertical(i, (int) centerJ, 2 * stateCount[1], stateCountTotal);
     if (!Float.isNaN(centerI)) {
       float estimatedModuleSize = (float) (stateCount[0] + stateCount[1] + stateCount[2]) / 3.0f;
       int max = possibleCenters.size();