1 files changed, 173 insertions, 0 deletions
diff --git a/xfa/fxbarcode/common/BC_GlobalHistogramBinarizer.cpp b/xfa/fxbarcode/common/BC_GlobalHistogramBinarizer.cpp
new file mode 100644
index 0000000000..d4a33229cf
--- /dev/null
+++ b/xfa/fxbarcode/common/BC_GlobalHistogramBinarizer.cpp
@@ -0,0 +1,173 @@
+// Copyright 2014 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+// Original code is licensed as follows:
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * 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.
+ */
+
+#include "xfa/fxbarcode/common/BC_GlobalHistogramBinarizer.h"
+
+#include <memory>
+
+#include "xfa/fxbarcode/BC_Binarizer.h"
+#include "xfa/fxbarcode/BC_LuminanceSource.h"
+#include "xfa/fxbarcode/common/BC_CommonBitArray.h"
+#include "xfa/fxbarcode/common/BC_CommonBitMatrix.h"
+#include "xfa/fxbarcode/utils.h"
+
+const int32_t LUMINANCE_BITS = 5;
+const int32_t LUMINANCE_SHIFT = 8 - LUMINANCE_BITS;
+const int32_t LUMINANCE_BUCKETS = 1 << LUMINANCE_BITS;
+
+CBC_GlobalHistogramBinarizer::CBC_GlobalHistogramBinarizer(
+    CBC_LuminanceSource* source)
+    : CBC_Binarizer(source) {}
+CBC_GlobalHistogramBinarizer::~CBC_GlobalHistogramBinarizer() {}
+CBC_CommonBitArray* CBC_GlobalHistogramBinarizer::GetBlackRow(
+    int32_t y,
+    CBC_CommonBitArray* row,
+    int32_t& e) {
+  CBC_LuminanceSource* source = GetLuminanceSource();
+  int32_t width = source->GetWidth();
+  std::unique_ptr<CBC_CommonBitArray> result(new CBC_CommonBitArray(width));
+  InitArrays(width);
+  CFX_ByteArray* localLuminances = source->GetRow(y, m_luminance, e);
+  if (e != BCExceptionNO) {
+    return result.release();
+  }
+  CFX_Int32Array localBuckets;
+  localBuckets.Copy(m_buckets);
+  int32_t x;
+  for (x = 0; x < width; x++) {
+    int32_t pixel = (*localLuminances)[x] & 0xff;
+    localBuckets[pixel >> LUMINANCE_SHIFT]++;
+  }
+  int32_t blackPoint = EstimateBlackPoint(localBuckets, e);
+  if (e != BCExceptionNO) {
+    return result.release();
+  }
+  int32_t left = (*localLuminances)[0] & 0xff;
+  int32_t center = (*localLuminances)[1] & 0xff;
+  for (x = 1; x < width - 1; x++) {
+    int32_t right = (*localLuminances)[x + 1] & 0xff;
+    int32_t luminance = ((center << 2) - left - right) >> 1;
+    if (luminance < blackPoint) {
+      result->Set(x);
+    }
+    left = center;
+    center = right;
+  }
+  return result.release();
+}
+CBC_CommonBitMatrix* CBC_GlobalHistogramBinarizer::GetBlackMatrix(int32_t& e) {
+  CBC_LuminanceSource* source = GetLuminanceSource();
+  int32_t width = source->GetWidth();
+  int32_t height = source->GetHeight();
+  std::unique_ptr<CBC_CommonBitMatrix> matrix(new CBC_CommonBitMatrix());
+  matrix->Init(width, height);
+  InitArrays(width);
+  CFX_Int32Array localBuckets;
+  localBuckets.Copy(m_buckets);
+  int32_t y;
+  for (y = 1; y < 5; y++) {
+    int32_t row = height * y / 5;
+    CFX_ByteArray* localLuminances = source->GetRow(row, m_luminance, e);
+    BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
+    int32_t right = (width << 2) / 5;
+    int32_t x;
+    for (x = width / 5; x < right; x++) {
+      int32_t pixel = (*localLuminances)[x] & 0xff;
+      localBuckets[pixel >> LUMINANCE_SHIFT]++;
+    }
+  }
+  int32_t blackPoint = EstimateBlackPoint(localBuckets, e);
+  BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
+  std::unique_ptr<CFX_ByteArray> localLuminances(source->GetMatrix());
+  for (y = 0; y < height; y++) {
+    int32_t offset = y * width;
+    for (int32_t x = 0; x < width; x++) {
+      int32_t pixel = (*localLuminances)[offset + x] & 0xff;
+      if (pixel < blackPoint) {
+        matrix->Set(x, y);
+      }
+    }
+  }
+  return matrix.release();
+}
+void CBC_GlobalHistogramBinarizer::InitArrays(int32_t luminanceSize) {
+  if (m_luminance.GetSize() < luminanceSize) {
+    m_luminance.SetSize(luminanceSize);
+  }
+  if (m_buckets.GetSize() <= 0) {
+    m_buckets.SetSize(LUMINANCE_BUCKETS);
+  } else {
+    int32_t x;
+    for (x = 0; x < LUMINANCE_BUCKETS; x++) {
+      m_buckets[x] = 0;
+    }
+  }
+}
+int32_t CBC_GlobalHistogramBinarizer::EstimateBlackPoint(
+    CFX_Int32Array& buckets,
+    int32_t& e) {
+  int32_t numBuckets = buckets.GetSize();
+  int32_t maxBucketCount = 0;
+  int32_t firstPeak = 0;
+  int32_t firstPeakSize = 0;
+  int32_t x;
+  for (x = 0; x < numBuckets; x++) {
+    if (buckets[x] > firstPeakSize) {
+      firstPeak = x;
+      firstPeakSize = buckets[x];
+    }
+    if (buckets[x] > maxBucketCount) {
+      maxBucketCount = buckets[x];
+    }
+  }
+  int32_t secondPeak = 0;
+  int32_t secondPeakScore = 0;
+  for (x = 0; x < numBuckets; x++) {
+    int32_t distanceToBiggest = x - firstPeak;
+    int32_t score = buckets[x] * distanceToBiggest * distanceToBiggest;
+    if (score > secondPeakScore) {
+      secondPeak = x;
+      secondPeakScore = score;
+    }
+  }
+  if (firstPeak > secondPeak) {
+    int32_t temp = firstPeak;
+    firstPeak = secondPeak;
+    secondPeak = temp;
+  }
+  if (secondPeak - firstPeak <= numBuckets >> 4) {
+    e = BCExceptionRead;
+    return 0;
+  }
+  int32_t bestValley = secondPeak - 1;
+  int32_t bestValleyScore = -1;
+  for (x = secondPeak - 1; x > firstPeak; x--) {
+    int32_t fromFirst = x - firstPeak;
+    int32_t score = fromFirst * fromFirst * (secondPeak - x) *
+                    (maxBucketCount - buckets[x]);
+    if (score > bestValleyScore) {
+      bestValley = x;
+      bestValleyScore = score;
+    }
+  }
+  return bestValley << LUMINANCE_SHIFT;
+}