tesseract-ocr/ccstruct/boxword.h

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// File:        boxword.h
// Description: Class to represent the bounding boxes of the output.
// Author:      Ray Smith
// Created:     Tue May 25 14:18:14 PDT 2010
//
// (C) Copyright 2010, 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_CSTRUCT_BOXWORD_H__
#define TESSERACT_CSTRUCT_BOXWORD_H__

#include "genericvector.h"
#include "rect.h"

class BLOCK;
class DENORM;
class PBLOB_LIST;
struct TWERD;
class UNICHARSET;
class WERD;
class WERD_CHOICE;
class WERD_RES;

namespace tesseract {

// ScriptPos tells whether a character is subscript, superscript or normal.
enum ScriptPos {
  SP_NORMAL,
  SP_SUBSCRIPT,
  SP_SUPERSCRIPT,
  SP_DROPCAP
};

// Class to hold an array of bounding boxes for an output word and
// the bounding box of the whole word.
class BoxWord {
 public:
  BoxWord();
  explicit BoxWord(const BoxWord& src);
  ~BoxWord();

  BoxWord& operator=(const BoxWord& src);

  void CopyFrom(const BoxWord& src);

  // Factory to build a BoxWord from a TWERD and the DENORM to switch
  // back to original image coordinates.
  // If the denorm is not NULL, then the output is denormalized and rotated
  // back to the original image coordinates.
  static BoxWord* CopyFromNormalized(const DENORM* denorm,
                                     TWERD* tessword);

  // Sets up the script_pos_ member using the tessword to get the bln
  // bounding boxes, the best_choice to get the unichars, and the unicharset
  // to get the target positions. If small_caps is true, sub/super are not
  // considered, but dropcaps are.
  void SetScriptPositions(const UNICHARSET& unicharset, bool small_caps,
                          TWERD* tessword, WERD_CHOICE* best_choice);

  // Clean up the bounding boxes from the polygonal approximation by
  // expanding slightly, then clipping to the blobs from the original_word
  // that overlap. If not null, the block provides the inverse rotation.
  void ClipToOriginalWord(const BLOCK* block, WERD* original_word);

  // Merges the boxes from start to end, not including end, and deletes
  // the boxes between start and end.
  void MergeBoxes(int start, int end);

  // Inserts a new box before the given index.
  // Recomputes the bounding box.
  void InsertBox(int index, const TBOX& box);

  // Deletes the box with the given index, and shuffles up the rest.
  // Recomputes the bounding box.
  void DeleteBox(int index);

  // Deletes all the boxes stored in BoxWord.
  void DeleteAllBoxes();

  // This and other putatively are the same, so call the (permanent) callback
  // for each blob index where the bounding boxes match.
  // The callback is deleted on completion.
  void ProcessMatchedBlobs(const TWERD& other, TessCallback1<int>* cb) const;

  const TBOX& bounding_box() const {
    return bbox_;
  }
  const int length() const {
    return length_;
  }
  const TBOX& BlobBox(int index) const {
    return boxes_[index];
  }
  ScriptPos BlobPosition(int index) const {
    if (index < 0 || index >= script_pos_.size())
      return SP_NORMAL;
    return script_pos_[index];
  }

 private:
  void ComputeBoundingBox();

  TBOX bbox_;
  int length_;
  GenericVector<TBOX> boxes_;
  GenericVector<ScriptPos> script_pos_;
};

}  // namespace tesseract.


#endif  // TESSERACT_CSTRUCT_BOXWORD_H__