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diff --git a/tesseract/src/dict/context.cpp b/tesseract/src/dict/context.cpp
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+++ b/tesseract/src/dict/context.cpp
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+/******************************************************************************
+ *
+ * File:         context.cpp  (Formerly context.c)
+ * Description:  Context checking functions
+ * Author:       Mark Seaman, OCR Technology
+ *
+ * (c) Copyright 1990, Hewlett-Packard Company.
+ ** 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 "dict.h"
+#include "unicharset.h"
+
+namespace tesseract {
+
+static const int kMinAbsoluteGarbageWordLength = 10;
+static const float kMinAbsoluteGarbageAlphanumFrac = 0.5f;
+
+const int case_state_table[6][4] = {
+    {/*  0. Beginning of word       */
+     /*    P   U   L   D                                          */
+     /* -1. Error on case           */
+     0, 1, 5, 4},
+    {/*  1. After initial capital    */
+     0, 3, 2, 4},
+    {/*  2. After lower case         */
+     0, -1, 2, -1},
+    {/*  3. After upper case         */
+     0, 3, -1, 4},
+    {/*  4. After a digit            */
+     0, -1, -1, 4},
+    {/*  5. After initial lower case */
+     5, -1, 2, -1},
+};
+
+int Dict::case_ok(const WERD_CHOICE &word) const {
+  int state = 0;
+  int x;
+  const UNICHARSET* unicharset = word.unicharset();
+  for (x = 0; x < word.length(); ++x) {
+    UNICHAR_ID ch_id = word.unichar_id(x);
+    if (unicharset->get_isupper(ch_id))
+      state = case_state_table[state][1];
+    else if (unicharset->get_islower(ch_id))
+      state = case_state_table[state][2];
+    else if (unicharset->get_isdigit(ch_id))
+      state = case_state_table[state][3];
+    else
+      state = case_state_table[state][0];
+    if (state == -1) return false;
+  }
+  return state != 5; // single lower is bad
+}
+
+bool Dict::absolute_garbage(const WERD_CHOICE &word,
+                            const UNICHARSET &unicharset) {
+  if (word.length() < kMinAbsoluteGarbageWordLength) return false;
+  int num_alphanum = 0;
+  for (int x = 0; x < word.length(); ++x) {
+    num_alphanum += (unicharset.get_isalpha(word.unichar_id(x)) ||
+                     unicharset.get_isdigit(word.unichar_id(x)));
+  }
+  return (static_cast<float>(num_alphanum) /
+          static_cast<float>(word.length()) < kMinAbsoluteGarbageAlphanumFrac);
+}
+
+}  // namespace tesseract