port relevant parts of r1937 to C++

git-svn-id: https://zxing.googlecode.com/svn/trunk@1962 59b500cc-1b3d-0410-9834-0bbf25fbcc57

cpp/core/src/zxing/Binarizer.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  Binarizer.cpp
  *  zxing

cpp/core/src/zxing/Result.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  Result.cpp
  *  zxing

cpp/core/src/zxing/common/BitArray.cpp

@@ -73,7 +73,7 @@ void BitArray::setBulk(size_t i, unsigned int newBits) {
 
 void BitArray::setRange(int start, int end) {
   if (end < start) {
-    throw new IllegalArgumentException("invalid call to BitArray::setRange");
+    throw IllegalArgumentException("invalid call to BitArray::setRange");
   }
   if (end == start) {
     return;

cpp/core/src/zxing/common/DetectorResult.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  DetectorResult.cpp
  *  zxing

cpp/core/src/zxing/common/GlobalHistogramBinarizer.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  GlobalHistogramBinarizer.cpp
  *  zxing

cpp/core/src/zxing/common/HybridBinarizer.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  HybridBinarizer.cpp
  *  zxing
@@ -31,7 +32,7 @@ static const int LUMINANCE_SHIFT = 8 - LUMINANCE_BITS;
 static const int LUMINANCE_BUCKETS = 1 << LUMINANCE_BITS;
 
 HybridBinarizer::HybridBinarizer(Ref<LuminanceSource> source) :
-  GlobalHistogramBinarizer(source), cached_matrix_(NULL), cached_row_(NULL), cached_row_num_(-1) {
+  GlobalHistogramBinarizer(source), matrix_(NULL), cached_row_(NULL), cached_row_num_(-1) {
 
 }
 
@@ -39,40 +40,43 @@ HybridBinarizer::~HybridBinarizer() {
 }
 
 
-Ref<BitMatrix> HybridBinarizer::getBlackMatrix() {
-  binarizeEntireImage();
-  return cached_matrix_;
-}
-
 Ref<Binarizer> HybridBinarizer::createBinarizer(Ref<LuminanceSource> source) {
   return Ref<Binarizer> (new HybridBinarizer(source));
 }
 
-void HybridBinarizer::binarizeEntireImage() {
-  if (cached_matrix_ == NULL) {
-    Ref<LuminanceSource> source = getLuminanceSource();
-    if (source->getWidth() >= MINIMUM_DIMENSION && source->getHeight() >= MINIMUM_DIMENSION) {
-      unsigned char* luminances = source->getMatrix();
-      int width = source->getWidth();
-      int height = source->getHeight();
+Ref<BitMatrix> HybridBinarizer::getBlackMatrix() {
+  // Calculates the final BitMatrix once for all requests. This could be called once from the
+  // constructor instead, but there are some advantages to doing it lazily, such as making
+  // profiling easier, and not doing heavy lifting when callers don't expect it.
+  if (matrix_) {
+    return matrix_;
+  }
+  LuminanceSource& source = *getLuminanceSource();
+  if (source.getWidth() >= MINIMUM_DIMENSION && source.getHeight() >= MINIMUM_DIMENSION) {
+    unsigned char* luminances = source.getMatrix();
+    int width = source.getWidth();
+    int height = source.getHeight();
     int subWidth = width >> 3;
-      if (width & 0x07) {
+    if ((width & 0x07) != 0) {
       subWidth++;
     }
     int subHeight = height >> 3;
-      if (height & 0x07) {
+    if ((height & 0x07) != 0) {
       subHeight++;
     }
-      int *blackPoints = calculateBlackPoints(luminances, subWidth, subHeight, width, height);
-      cached_matrix_.reset(new BitMatrix(width,height));
-      calculateThresholdForBlock(luminances, subWidth, subHeight, width, height, blackPoints, cached_matrix_);
+    int* blackPoints = calculateBlackPoints(luminances, subWidth, subHeight, width, height);
+
+    Ref<BitMatrix> newMatrix (new BitMatrix(width, height));
+    calculateThresholdForBlock(luminances, subWidth, subHeight, width, height, blackPoints, newMatrix);
+    matrix_ = newMatrix;
+
     delete [] blackPoints;
     delete [] luminances;
   } else {
     // If the image is too small, fall back to the global histogram approach.
-      cached_matrix_.reset(GlobalHistogramBinarizer::getBlackMatrix());
-    }
+    matrix_ = GlobalHistogramBinarizer::getBlackMatrix();
   }
+  return matrix_;
 }
 
 void HybridBinarizer::calculateThresholdForBlock(unsigned char* luminances, int subWidth, int subHeight,

cpp/core/src/zxing/common/HybridBinarizer.h

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 #ifndef __HYBRIDBINARIZER_H__
 #define __HYBRIDBINARIZER_H__
 /*
@@ -29,7 +30,7 @@ namespace zxing {
 	
 	class HybridBinarizer : public GlobalHistogramBinarizer {
 	 private:
-    Ref<BitMatrix> cached_matrix_;
+    Ref<BitMatrix> matrix_;
 	  Ref<BitArray> cached_row_;
 	  int cached_row_num_;
 
@@ -40,7 +41,6 @@ namespace zxing {
 		virtual Ref<BitMatrix> getBlackMatrix();
 		Ref<Binarizer> createBinarizer(Ref<LuminanceSource> source);
   private:
-    void binarizeEntireImage();
     // We'll be using one-D arrays because C++ can't dynamically allocate 2D arrays
     int* calculateBlackPoints(unsigned char* luminances, int subWidth, int subHeight,
       int width, int height);

cpp/core/src/zxing/datamatrix/detector/Detector.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  Detector.cpp
  *  zxing

cpp/core/src/zxing/datamatrix/detector/Detector.h

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 #ifndef __DETECTOR_H__
 #define __DETECTOR_H__
 

cpp/core/src/zxing/oned/OneDReader.cpp

@@ -1,3 +1,4 @@
+// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  OneDReader.cpp
  *  ZXing