publictypes.h

// File:        publictypes.h
// Description: Types used in both the API and internally
// Author:      Ray Smith
// Created:     Wed Mar 03 09:22:53 PST 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_CCSTRUCT_PUBLICTYPES_H_
#define TESSERACT_CCSTRUCT_PUBLICTYPES_H_

// This file contains types that are used both by the API and internally
// to Tesseract. In order to decouple the API from Tesseract and prevent cyclic
// dependencies, THIS FILE SHOULD NOT DEPEND ON ANY OTHER PART OF TESSERACT.
// Restated: It is OK for low-level Tesseract files to include publictypes.h,
// but not for the low-level tesseract code to include top-level API code.
// This file should not use other Tesseract types, as that would drag
// their includes into the API-level.
// API-level code should include apitypes.h in preference to this file.

constexpr int kPointsPerInch = 72;
constexpr int kMinCredibleResolution = 70;
constexpr int kMaxCredibleResolution = 2400;
constexpr int kResolutionEstimationFactor = 10;

enum PolyBlockType {
  PT_UNKNOWN,        // Type is not yet known. Keep as the first element.
  PT_FLOWING_TEXT,   // Text that lives inside a column.
  PT_HEADING_TEXT,   // Text that spans more than one column.
  PT_PULLOUT_TEXT,   // Text that is in a cross-column pull-out region.
  PT_EQUATION,       // Partition belonging to an equation region.
  PT_INLINE_EQUATION,  // Partition has inline equation.
  PT_TABLE,          // Partition belonging to a table region.
  PT_VERTICAL_TEXT,  // Text-line runs vertically.
  PT_CAPTION_TEXT,   // Text that belongs to an image.
  PT_FLOWING_IMAGE,  // Image that lives inside a column.
  PT_HEADING_IMAGE,  // Image that spans more than one column.
  PT_PULLOUT_IMAGE,  // Image that is in a cross-column pull-out region.
  PT_HORZ_LINE,      // Horizontal Line.
  PT_VERT_LINE,      // Vertical Line.
  PT_NOISE,          // Lies outside of any column.
  PT_COUNT
};

inline bool PTIsLineType(PolyBlockType type) {
  return type == PT_HORZ_LINE || type == PT_VERT_LINE;
}
inline bool PTIsImageType(PolyBlockType type) {
  return type == PT_FLOWING_IMAGE || type == PT_HEADING_IMAGE ||
         type == PT_PULLOUT_IMAGE;
}
inline bool PTIsTextType(PolyBlockType type) {
  return type == PT_FLOWING_TEXT || type == PT_HEADING_TEXT ||
         type == PT_PULLOUT_TEXT || type == PT_TABLE ||
         type == PT_VERTICAL_TEXT || type == PT_CAPTION_TEXT ||
         type == PT_INLINE_EQUATION;
}
// Returns true if PolyBlockType is of pullout(inter-column) type
inline bool PTIsPulloutType(PolyBlockType type) {
  return type == PT_PULLOUT_IMAGE || type == PT_PULLOUT_TEXT;
}

extern const char* kPolyBlockNames[];

namespace tesseract {
enum Orientation {
  ORIENTATION_PAGE_UP = 0,
  ORIENTATION_PAGE_RIGHT = 1,
  ORIENTATION_PAGE_DOWN = 2,
  ORIENTATION_PAGE_LEFT = 3,
};

enum WritingDirection {
  WRITING_DIRECTION_LEFT_TO_RIGHT = 0,
  WRITING_DIRECTION_RIGHT_TO_LEFT = 1,
  WRITING_DIRECTION_TOP_TO_BOTTOM = 2,
};

enum TextlineOrder {
  TEXTLINE_ORDER_LEFT_TO_RIGHT = 0,
  TEXTLINE_ORDER_RIGHT_TO_LEFT = 1,
  TEXTLINE_ORDER_TOP_TO_BOTTOM = 2,
};

enum PageSegMode {
  PSM_OSD_ONLY,       
  PSM_AUTO_OSD,       
  PSM_AUTO_ONLY,      
  PSM_AUTO,           
  PSM_SINGLE_COLUMN,  
  PSM_SINGLE_BLOCK_VERT_TEXT,  
  PSM_SINGLE_BLOCK,   
  PSM_SINGLE_LINE,    
  PSM_SINGLE_WORD,    
  PSM_CIRCLE_WORD,    
  PSM_SINGLE_CHAR,    
  PSM_SPARSE_TEXT,    
  PSM_SPARSE_TEXT_OSD,  
  PSM_RAW_LINE,       

  PSM_COUNT           
};

inline bool PSM_OSD_ENABLED(int pageseg_mode) {
  return pageseg_mode <= PSM_AUTO_OSD || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_ORIENTATION_ENABLED(int pageseg_mode) {
  return pageseg_mode <= PSM_AUTO || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_COL_FIND_ENABLED(int pageseg_mode) {
  return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_AUTO;
}
inline bool PSM_SPARSE(int pageseg_mode) {
  return pageseg_mode == PSM_SPARSE_TEXT || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_BLOCK_FIND_ENABLED(int pageseg_mode) {
  return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_COLUMN;
}
inline bool PSM_LINE_FIND_ENABLED(int pageseg_mode) {
  return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_BLOCK;
}
inline bool PSM_WORD_FIND_ENABLED(int pageseg_mode) {
  return (pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_LINE) ||
      pageseg_mode == PSM_SPARSE_TEXT || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}

enum PageIteratorLevel {
  RIL_BLOCK,     // Block of text/image/separator line.
  RIL_PARA,      // Paragraph within a block.
  RIL_TEXTLINE,  // Line within a paragraph.
  RIL_WORD,      // Word within a textline.
  RIL_SYMBOL     // Symbol/character within a word.
};

enum ParagraphJustification {
  JUSTIFICATION_UNKNOWN,
  JUSTIFICATION_LEFT,
  JUSTIFICATION_CENTER,
  JUSTIFICATION_RIGHT,
};

enum OcrEngineMode {
  OEM_TESSERACT_ONLY,           // Run Tesseract only - fastest; deprecated
  OEM_LSTM_ONLY,                // Run just the LSTM line recognizer.
  OEM_TESSERACT_LSTM_COMBINED,  // Run the LSTM recognizer, but allow fallback
                                // to Tesseract when things get difficult.
                                // deprecated
  OEM_DEFAULT,                  // Specify this mode when calling init_*(),
                                // to indicate that any of the above modes
                                // should be automatically inferred from the
                                // variables in the language-specific config,
                                // command-line configs, or if not specified
                                // in any of the above should be set to the
                                // default OEM_TESSERACT_ONLY.
  OEM_COUNT                     // Number of OEMs
};

}  // namespace tesseract.

#endif  // TESSERACT_CCSTRUCT_PUBLICTYPES_H_