Add sharpening filter to this implementation too

[zxing.git] / javame / src / com / google / zxing / client / j2me / LCDUIImageMonochromeBitmapSource.java

diff --git a/javame/src/com/google/zxing/client/j2me/LCDUIImageMonochromeBitmapSource.java b/javame/src/com/google/zxing/client/j2me/LCDUIImageMonochromeBitmapSource.java
index 266cebf..f123abb 100644 (file)
--- a/javame/src/com/google/zxing/client/j2me/LCDUIImageMonochromeBitmapSource.java
+++ b/javame/src/com/google/zxing/client/j2me/LCDUIImageMonochromeBitmapSource.java
@@ -62,9 +62,30 @@ public final class LCDUIImageMonochromeBitmapSource implements MonochromeBitmapS
     } else {
       row.clear();
     }
-    for (int i = 0, offset = y * width + startX; i < getWidth; i++, offset++) {
-      if (computeRGBLuminance(rgbPixels[offset]) < blackPoint) {
-        row.set(i);
+
+    // If the current decoder calculated the blackPoint based on one row, assume we're trying to
+    // decode a 1D barcode, and apply some sharpening.
+    // TODO: We may want to add a fifth parameter to request the amount of shapening to be done.
+    if (lastMethod.equals(BlackPointEstimationMethod.ROW_SAMPLING)) {
+      int offset = y * width + startX;
+      int left = computeRGBLuminance(rgbPixels[offset]);
+      offset++;
+      int center = computeRGBLuminance(rgbPixels[offset]);
+      for (int i = 1; i < getWidth - 1; i++, offset++) {
+        int right = computeRGBLuminance(rgbPixels[offset + 1]);
+        // Simple -1 4 -1 box filter with a weight of 2
+        int luminance = ((center << 2) - left - right) >> 1;
+        if (luminance < blackPoint) {
+          row.set(i);
+        }
+        left = center;
+        center = right;
+      }
+    } else {
+      for (int i = 0, offset = y * width + startX; i < getWidth; i++, offset++) {
+        if (computeRGBLuminance(rgbPixels[offset]) < blackPoint) {
+          row.set(i);
+        }
       }
     }
     return row;