githubmirror/tesseract

src/ccstruct/ocrblock.h
227 строк7 KB
Stefan Weil
Prepare support for image width and height larger than 32767
27 окт 2021, 09:45
27 окт 2021, 09:4559fbad0
/**********************************************************************
 * File:        ocrblock.h  (Formerly block.h)
 * Description: Page block class definition.
 * Author:      Ray Smith
 *
 * (C) Copyright 1991, Hewlett-Packard Ltd.
 ** 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 OCRBLOCK_H
#define OCRBLOCK_H

#include "ocrpara.h"
#include "ocrrow.h"
#include "pdblock.h"

namespace tesseract {

class BLOCK; // forward decl

ELISTIZEH(BLOCK)

class TESS_API BLOCK : public ELIST_LINK
// page block
{
  friend class BLOCK_RECT_IT; // block iterator
public:
  BLOCK() : re_rotation_(1.0f, 0.0f), classify_rotation_(1.0f, 0.0f), skew_(1.0f, 0.0f) {}
  BLOCK(const char *name, ///< filename
        bool prop,        ///< proportional
        int16_t kern,     ///< kerning
        int16_t space,    ///< spacing
        TDimension xmin,  ///< bottom left
        TDimension ymin,
        TDimension xmax,  ///< top right
        TDimension ymax);

  ~BLOCK() = default;

  /**
   * set space size etc.
   * @param prop proportional
   * @param kern inter char size
   * @param space inter word size
   * @param ch_pitch pitch if fixed
   */
  void set_stats(bool prop, int16_t kern, int16_t space, int16_t ch_pitch) {
    proportional = prop;
    kerning = static_cast<int8_t>(kern);
    spacing = space;
    pitch = ch_pitch;
  }
  /// set char size
  void set_xheight(int32_t height) {
    xheight = height;
  }
  /// set font class
  void set_font_class(int16_t font) {
    font_class = font;
  }
  /// return proportional
  bool prop() const {
    return proportional;
  }
  bool right_to_left() const {
    return right_to_left_;
  }
  void set_right_to_left(bool value) {
    right_to_left_ = value;
  }
  /// return pitch
  int32_t fixed_pitch() const {
    return pitch;
  }
  /// return kerning
  int16_t kern() const {
    return kerning;
  }
  /// return font class
  int16_t font() const {
    return font_class;
  }
  /// return spacing
  int16_t space() const {
    return spacing;
  }
  /// return filename
  const char *name() const {
    return filename.c_str();
  }
  /// return xheight
  int32_t x_height() const {
    return xheight;
  }
  float cell_over_xheight() const {
    return cell_over_xheight_;
  }
  void set_cell_over_xheight(float ratio) {
    cell_over_xheight_ = ratio;
  }
  /// get rows
  ROW_LIST *row_list() {
    return &rows;
  }
  // Compute the margins between the edges of each row and this block's
  // polyblock, and store the results in the rows.
  void compute_row_margins();

  // get paragraphs
  PARA_LIST *para_list() {
    return &paras_;
  }
  /// get blobs
  C_BLOB_LIST *blob_list() {
    return &c_blobs;
  }
  C_BLOB_LIST *reject_blobs() {
    return &rej_blobs;
  }
  FCOORD re_rotation() const {
    return re_rotation_; // How to transform coords back to image.
  }
  void set_re_rotation(const FCOORD &rotation) {
    re_rotation_ = rotation;
  }
  FCOORD classify_rotation() const {
    return classify_rotation_; // Apply this before classifying.
  }
  void set_classify_rotation(const FCOORD &rotation) {
    classify_rotation_ = rotation;
  }
  FCOORD skew() const {
    return skew_; // Direction of true horizontal.
  }
  void set_skew(const FCOORD &skew) {
    skew_ = skew;
  }
  const ICOORD &median_size() const {
    return median_size_;
  }
  void set_median_size(int x, int y) {
    median_size_.set_x(x);
    median_size_.set_y(y);
  }

  Image render_mask(TBOX *mask_box) {
    return pdblk.render_mask(re_rotation_, mask_box);
  }

  // Returns the bounding box including the desired combination of upper and
  // lower noise/diacritic elements.
  TBOX restricted_bounding_box(bool upper_dots, bool lower_dots) const;

  // Reflects the polygon in the y-axis and recomputes the bounding_box.
  // Does nothing to any contained rows/words/blobs etc.
  void reflect_polygon_in_y_axis();

  void rotate(const FCOORD &rotation);

  /// decreasing y order
  void sort_rows();

  /// shrink white space
  void compress();

  /// check proportional
  void check_pitch();

  /// shrink white space and move by vector
  void compress(const ICOORD vec);

  /// dump whole table
  void print(FILE *fp, bool dump);

  BLOCK &operator=(const BLOCK &source);
  PDBLK pdblk; ///< Page Description Block

private:
  bool proportional = false;       ///< proportional
  bool right_to_left_ = false;     ///< major script is right to left.
  int8_t kerning = 0;              ///< inter blob gap
  int16_t spacing = 0;             ///< inter word gap
  int16_t pitch = 0;               ///< pitch of non-props
  int16_t font_class = 0;          ///< correct font class
  int32_t xheight = 0;             ///< height of chars
  float cell_over_xheight_ = 0.0f; ///< Ratio of cell height to xheight.
  std::string filename;            ///< name of block
  ROW_LIST rows;                   ///< rows in block
  PARA_LIST paras_;                ///< paragraphs of block
  C_BLOB_LIST c_blobs;             ///< before textord
  C_BLOB_LIST rej_blobs;           ///< duff stuff
  FCOORD re_rotation_;             ///< How to transform coords back to image.
  FCOORD classify_rotation_;       ///< Apply this before classifying.
  FCOORD skew_;                    ///< Direction of true horizontal.
  ICOORD median_size_;             ///< Median size of blobs.
};

// A function to print segmentation stats for the given block list.
void PrintSegmentationStats(BLOCK_LIST *block_list);

// Extracts blobs fromo the given block list and adds them to the output list.
// The block list must have been created by performing a page segmentation.
void ExtractBlobsFromSegmentation(BLOCK_LIST *blocks, C_BLOB_LIST *output_blob_list);

// Refreshes the words in the block_list by using blobs in the
// new_blobs list.
// Block list must have word segmentation in it.
// It consumes the blobs provided in the new_blobs list. The blobs leftover in
// the new_blobs list after the call weren't matched to any blobs of the words
// in block list.
// The output not_found_blobs is a list of blobs from the original segmentation
// in the block_list for which no corresponding new blobs were found.
void RefreshWordBlobsFromNewBlobs(BLOCK_LIST *block_list, C_BLOB_LIST *new_blobs,
                                  C_BLOB_LIST *not_found_blobs);

} // namespace tesseract

#endif