resultiterator.h

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// SPDX-License-Identifier: Apache-2.0
// File:        resultiterator.h
// Description: Iterator for tesseract results that is capable of
//              iterating in proper reading order over Bi Directional
//              (e.g. mixed Hebrew and English) text.
// Author:      David Eger
//
// (C) Copyright 2011, Google Inc.
// 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.
 
#ifndef TESSERACT_CCMAIN_RESULT_ITERATOR_H_
#define TESSERACT_CCMAIN_RESULT_ITERATOR_H_
 
#include "export.h"            // for TESS_API, TESS_LOCAL
#include "ltrresultiterator.h" // for LTRResultIterator
#include "publictypes.h"       // for PageIteratorLevel
#include "unichar.h"           // for StrongScriptDirection
 
#include <set>    // for std::pair
#include <vector> // for std::vector
 
namespace tesseract {
 
class TESS_API ResultIterator : public LTRResultIterator {
public:
  static ResultIterator *StartOfParagraph(const LTRResultIterator &resit);
 
  ~ResultIterator() override = default;
 
  // ============= Moving around within the page ============.
  void Begin() override;
 
  bool Next(PageIteratorLevel level) override;
 
  bool IsAtBeginningOf(PageIteratorLevel level) const override;
 
  bool IsAtFinalElement(PageIteratorLevel level,
                        PageIteratorLevel element) const override;
 
  // ============= Functions that refer to words only ============.
  // Returns the number of blanks before the current word.
  int BlanksBeforeWord() const;
 
  // ============= Accessing data ==============.
 
  virtual char *GetUTF8Text(PageIteratorLevel level) const;
 
  virtual std::vector<std::vector<std::vector<std::pair<const char *, float>>>>
      *GetRawLSTMTimesteps() const;
  virtual std::vector<std::vector<std::pair<const char *, float>>>
      *GetBestLSTMSymbolChoices() const;
 
  bool ParagraphIsLtr() const;
 
  // ============= Exposed only for testing =============.
 
  static void CalculateTextlineOrder(
      bool paragraph_is_ltr,
      const std::vector<StrongScriptDirection> &word_dirs,
      std::vector<int> *reading_order);
 
  static const int kMinorRunStart;
  static const int kMinorRunEnd;
  static const int kComplexWord;
 
protected:
  explicit ResultIterator(const LTRResultIterator &resit);
 
private:
  bool CurrentParagraphIsLtr() const;
 
  void CalculateTextlineOrder(bool paragraph_is_ltr,
                              const LTRResultIterator &resit,
                              std::vector<int> *indices) const;
  void CalculateTextlineOrder(bool paragraph_is_ltr,
                              const LTRResultIterator &resit,
                              std::vector<StrongScriptDirection> *ssd,
                              std::vector<int> *indices) const;
 
  int LTRWordIndex() const;
 
  void CalculateBlobOrder(std::vector<int> *blob_indices) const;
 
  void MoveToLogicalStartOfTextline();
 
  void MoveToLogicalStartOfWord();
 
  bool IsAtFinalSymbolOfWord() const;
 
  bool IsAtFirstSymbolOfWord() const;
 
  void AppendSuffixMarks(std::string *text) const;
 
  void AppendUTF8WordText(std::string *text) const;
 
  void IterateAndAppendUTF8TextlineText(std::string *text);
 
  void AppendUTF8ParagraphText(std::string *text) const;
 
  bool BidiDebug(int min_level) const;
 
  bool current_paragraph_is_ltr_;
 
  bool at_beginning_of_minor_run_;
 
  bool in_minor_direction_;
 
  bool preserve_interword_spaces_;
};
 
} // namespace tesseract.
 
#endif // TESSERACT_CCMAIN_RESULT_ITERATOR_H_