diff mupdf-source/thirdparty/tesseract/src/ccmain/fixspace.cpp @ 2:b50eed0cc0ef upstream

ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/ccmain/fixspace.cpp	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,862 @@
+/******************************************************************
+ * File:        fixspace.cpp  (Formerly fixspace.c)
+ * Description: Implements a pass over the page res, exploring the alternative
+ *              spacing possibilities, trying to use context to improve the
+ *              word spacing
+ * Author:      Phil Cheatle
+ *
+ * (C) Copyright 1993, 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.
+ *
+ **********************************************************************/
+
+#include "fixspace.h"
+
+#include "blobs.h"          // for TWERD, TBLOB, TESSLINE
+#include "boxword.h"        // for BoxWord
+#include "errcode.h"        // for ASSERT_HOST
+#include "normalis.h"       // for kBlnXHeight, kBlnBaselineOffset
+#include "pageres.h"        // for WERD_RES_IT, WERD_RES, WERD_RES_LIST
+#include "params.h"         // for IntParam, StringParam, BoolParam, DoubleParam, ...
+#include "ratngs.h"         // for WERD_CHOICE, FREQ_DAWG_PERM, NUMBER_PERM
+#include "rect.h"           // for TBOX
+#include "stepblob.h"       // for C_BLOB_IT, C_BLOB_LIST, C_BLOB
+#include "tesseractclass.h" // for Tesseract, TesseractStats, WordData
+#include "tessvars.h"       // for debug_fp
+#include "tprintf.h"        // for tprintf
+#include "unicharset.h"     // for UNICHARSET
+#include "werd.h"           // for WERD, W_EOL, W_FUZZY_NON, W_FUZZY_SP
+
+#include <tesseract/ocrclass.h> // for ETEXT_DESC
+#include <tesseract/unichar.h>  // for UNICHAR_ID
+
+#include <cstdint> // for INT16_MAX, int16_t, int32_t
+
+namespace tesseract {
+
+class BLOCK;
+class ROW;
+
+#define PERFECT_WERDS 999
+
+/**********************************************************************
+ *  c_blob_comparator()
+ *
+ *  Blob comparator used to sort a blob list so that blobs are in increasing
+ *  order of left edge.
+ **********************************************************************/
+
+static int c_blob_comparator( // sort blobs
+    const void *blob1p,       // ptr to ptr to blob1
+    const void *blob2p        // ptr to ptr to blob2
+) {
+  const C_BLOB *blob1 = *reinterpret_cast<const C_BLOB *const *>(blob1p);
+  const C_BLOB *blob2 = *reinterpret_cast<const C_BLOB *const *>(blob2p);
+
+  return blob1->bounding_box().left() - blob2->bounding_box().left();
+}
+
+/**
+ * @name fix_fuzzy_spaces()
+ * Walk over the page finding sequences of words joined by fuzzy spaces. Extract
+ * them as a sublist, process the sublist to find the optimal arrangement of
+ * spaces then replace the sublist in the ROW_RES.
+ *
+ * @param monitor progress monitor
+ * @param word_count count of words in doc
+ * @param[out] page_res
+ */
+void Tesseract::fix_fuzzy_spaces(ETEXT_DESC *monitor, int32_t word_count, PAGE_RES *page_res) {
+  BLOCK_RES_IT block_res_it;
+  ROW_RES_IT row_res_it;
+  WERD_RES_IT word_res_it_from;
+  WERD_RES_IT word_res_it_to;
+  WERD_RES *word_res;
+  WERD_RES_LIST fuzzy_space_words;
+  int16_t new_length;
+  bool prevent_null_wd_fixsp; // DON'T process blobless wds
+  int32_t word_index;         // current word
+
+  block_res_it.set_to_list(&page_res->block_res_list);
+  word_index = 0;
+  for (block_res_it.mark_cycle_pt(); !block_res_it.cycled_list(); block_res_it.forward()) {
+    row_res_it.set_to_list(&block_res_it.data()->row_res_list);
+    for (row_res_it.mark_cycle_pt(); !row_res_it.cycled_list(); row_res_it.forward()) {
+      word_res_it_from.set_to_list(&row_res_it.data()->word_res_list);
+      while (!word_res_it_from.at_last()) {
+        word_res = word_res_it_from.data();
+        while (!word_res_it_from.at_last() &&
+               !(word_res->combination ||
+                 word_res_it_from.data_relative(1)->word->flag(W_FUZZY_NON) ||
+                 word_res_it_from.data_relative(1)->word->flag(W_FUZZY_SP))) {
+          fix_sp_fp_word(word_res_it_from, row_res_it.data()->row, block_res_it.data()->block);
+          word_res = word_res_it_from.forward();
+          word_index++;
+          if (monitor != nullptr) {
+            monitor->ocr_alive = true;
+            monitor->progress = 90 + 5 * word_index / word_count;
+            if (monitor->deadline_exceeded() ||
+                (monitor->cancel != nullptr &&
+                 (*monitor->cancel)(monitor->cancel_this, stats_.dict_words))) {
+              return;
+            }
+          }
+        }
+
+        if (!word_res_it_from.at_last()) {
+          word_res_it_to = word_res_it_from;
+          prevent_null_wd_fixsp = word_res->word->cblob_list()->empty();
+          if (check_debug_pt(word_res, 60)) {
+            debug_fix_space_level.set_value(10);
+          }
+          word_res_it_to.forward();
+          word_index++;
+          if (monitor != nullptr) {
+            monitor->ocr_alive = true;
+            monitor->progress = 90 + 5 * word_index / word_count;
+            if (monitor->deadline_exceeded() ||
+                (monitor->cancel != nullptr &&
+                 (*monitor->cancel)(monitor->cancel_this, stats_.dict_words))) {
+              return;
+            }
+          }
+          while (!word_res_it_to.at_last() &&
+                 (word_res_it_to.data_relative(1)->word->flag(W_FUZZY_NON) ||
+                  word_res_it_to.data_relative(1)->word->flag(W_FUZZY_SP))) {
+            if (check_debug_pt(word_res, 60)) {
+              debug_fix_space_level.set_value(10);
+            }
+            if (word_res->word->cblob_list()->empty()) {
+              prevent_null_wd_fixsp = true;
+            }
+            word_res = word_res_it_to.forward();
+          }
+          if (check_debug_pt(word_res, 60)) {
+            debug_fix_space_level.set_value(10);
+          }
+          if (word_res->word->cblob_list()->empty()) {
+            prevent_null_wd_fixsp = true;
+          }
+          if (prevent_null_wd_fixsp) {
+            word_res_it_from = word_res_it_to;
+          } else {
+            fuzzy_space_words.assign_to_sublist(&word_res_it_from, &word_res_it_to);
+            fix_fuzzy_space_list(fuzzy_space_words, row_res_it.data()->row,
+                                 block_res_it.data()->block);
+            new_length = fuzzy_space_words.length();
+            word_res_it_from.add_list_before(&fuzzy_space_words);
+            for (; !word_res_it_from.at_last() && new_length > 0; new_length--) {
+              word_res_it_from.forward();
+            }
+          }
+          if (test_pt) {
+            debug_fix_space_level.set_value(0);
+          }
+        }
+        fix_sp_fp_word(word_res_it_from, row_res_it.data()->row, block_res_it.data()->block);
+        // Last word in row
+      }
+    }
+  }
+}
+
+void Tesseract::fix_fuzzy_space_list(WERD_RES_LIST &best_perm, ROW *row, BLOCK *block) {
+  int16_t best_score;
+  WERD_RES_LIST current_perm;
+  bool improved = false;
+
+  best_score = eval_word_spacing(best_perm); // default score
+  dump_words(best_perm, best_score, 1, improved);
+
+  if (best_score != PERFECT_WERDS) {
+    initialise_search(best_perm, current_perm);
+  }
+
+  while ((best_score != PERFECT_WERDS) && !current_perm.empty()) {
+    match_current_words(current_perm, row, block);
+    int16_t current_score = eval_word_spacing(current_perm);
+    dump_words(current_perm, current_score, 2, improved);
+    if (current_score > best_score) {
+      best_perm.clear();
+      best_perm.deep_copy(&current_perm, &WERD_RES::deep_copy);
+      best_score = current_score;
+      improved = true;
+    }
+    if (current_score < PERFECT_WERDS) {
+      transform_to_next_perm(current_perm);
+    }
+  }
+  dump_words(best_perm, best_score, 3, improved);
+}
+
+void initialise_search(WERD_RES_LIST &src_list, WERD_RES_LIST &new_list) {
+  WERD_RES_IT src_it(&src_list);
+  WERD_RES_IT new_it(&new_list);
+  WERD_RES *new_wd;
+
+  for (src_it.mark_cycle_pt(); !src_it.cycled_list(); src_it.forward()) {
+    WERD_RES *src_wd = src_it.data();
+    if (!src_wd->combination) {
+      new_wd = WERD_RES::deep_copy(src_wd);
+      new_wd->combination = false;
+      new_wd->part_of_combo = false;
+      new_it.add_after_then_move(new_wd);
+    }
+  }
+}
+
+void Tesseract::match_current_words(WERD_RES_LIST &words, ROW *row, BLOCK *block) {
+  WERD_RES_IT word_it(&words);
+  WERD_RES *word;
+  // Since we are not using PAGE_RES to iterate over words, we need to update
+  // prev_word_best_choice_ before calling classify_word_pass2().
+  prev_word_best_choice_ = nullptr;
+  for (word_it.mark_cycle_pt(); !word_it.cycled_list(); word_it.forward()) {
+    word = word_it.data();
+    if ((!word->part_of_combo) && (word->box_word == nullptr)) {
+      WordData word_data(block, row, word);
+      SetupWordPassN(2, &word_data);
+      classify_word_and_language(2, nullptr, &word_data);
+    }
+    prev_word_best_choice_ = word->best_choice;
+  }
+}
+
+/**
+ * @name eval_word_spacing()
+ * The basic measure is the number of characters in contextually confirmed
+ * words. (I.e the word is done)
+ * If all words are contextually confirmed the evaluation is deemed perfect.
+ *
+ * Some fiddles are done to handle "1"s as these are VERY frequent causes of
+ * fuzzy spaces. The problem with the basic measure is that "561 63" would score
+ * the same as "56163", though given our knowledge that the space is fuzzy, and
+ * that there is a "1" next to the fuzzy space, we need to ensure that "56163"
+ * is preferred.
+ *
+ * The solution is to NOT COUNT the score of any word which has a digit at one
+ * end and a "1Il" as the character the other side of the space.
+ *
+ * Conversely, any character next to a "1" within a word is counted as a
+ * positive score. Thus "561 63" would score 4 (3 chars in a numeric word plus 1
+ * side of the "1" joined).  "56163" would score 7 - all chars in a numeric word
+ * + 2 sides of a "1" joined.
+ *
+ * The joined 1 rule is applied to any word REGARDLESS of contextual
+ * confirmation.  Thus "PS7a71 3/7a" scores 1 (neither word is contexutally
+ * confirmed. The only score is from the joined 1. "PS7a713/7a" scores 2.
+ *
+ */
+int16_t Tesseract::eval_word_spacing(WERD_RES_LIST &word_res_list) {
+  WERD_RES_IT word_res_it(&word_res_list);
+  int16_t total_score = 0;
+  int16_t word_count = 0;
+  int16_t done_word_count = 0;
+  int i;
+  int16_t offset;
+  int16_t prev_word_score = 0;
+  bool prev_word_done = false;
+  bool prev_char_1 = false;     // prev ch a "1/I/l"?
+  bool prev_char_digit = false; // prev ch 2..9 or 0
+  const char *punct_chars = "!\"`',.:;";
+  do {
+    // current word
+    WERD_RES *word = word_res_it.data();
+    bool word_done = fixspace_thinks_word_done(word);
+    word_count++;
+    if (word->tess_failed) {
+      total_score += prev_word_score;
+      if (prev_word_done) {
+        done_word_count++;
+      }
+      prev_word_score = 0;
+      prev_char_1 = false;
+      prev_char_digit = false;
+      prev_word_done = false;
+    } else {
+      /*
+  Can we add the prev word score and potentially count this word?
+  Yes IF it didn't end in a 1 when the first char of this word is a digit
+    AND it didn't end in a digit when the first char of this word is a 1
+*/
+      auto word_len = word->reject_map.length();
+      bool current_word_ok_so_far = false;
+      if (!((prev_char_1 && digit_or_numeric_punct(word, 0)) ||
+            (prev_char_digit &&
+             ((word_done && word->best_choice->unichar_lengths().c_str()[0] == 1 &&
+               word->best_choice->unichar_string()[0] == '1') ||
+              (!word_done &&
+               conflict_set_I_l_1.contains(word->best_choice->unichar_string()[0])))))) {
+        total_score += prev_word_score;
+        if (prev_word_done) {
+          done_word_count++;
+        }
+        current_word_ok_so_far = word_done;
+      }
+
+      if (current_word_ok_so_far) {
+        prev_word_done = true;
+        prev_word_score = word_len;
+      } else {
+        prev_word_done = false;
+        prev_word_score = 0;
+      }
+
+      /* Add 1 to total score for every joined 1 regardless of context and
+   rejtn */
+      for (i = 0, prev_char_1 = false; i < word_len; i++) {
+        bool current_char_1 = word->best_choice->unichar_string()[i] == '1';
+        if (prev_char_1 || (current_char_1 && (i > 0))) {
+          total_score++;
+        }
+        prev_char_1 = current_char_1;
+      }
+
+      /* Add 1 to total score for every joined punctuation regardless of context
+  and rejtn */
+      if (tessedit_prefer_joined_punct) {
+        bool prev_char_punct;
+        for (i = 0, offset = 0, prev_char_punct = false; i < word_len;
+             offset += word->best_choice->unichar_lengths()[i++]) {
+          bool current_char_punct =
+              strchr(punct_chars, word->best_choice->unichar_string()[offset]) != nullptr;
+          if (prev_char_punct || (current_char_punct && i > 0)) {
+            total_score++;
+          }
+          prev_char_punct = current_char_punct;
+        }
+      }
+      prev_char_digit = digit_or_numeric_punct(word, word_len - 1);
+      for (i = 0, offset = 0; i < word_len - 1;
+           offset += word->best_choice->unichar_lengths()[i++]) {
+        ;
+      }
+      prev_char_1 =
+          ((word_done && (word->best_choice->unichar_string()[offset] == '1')) ||
+           (!word_done &&
+            conflict_set_I_l_1.contains(word->best_choice->unichar_string()[offset])));
+    }
+    /* Find next word */
+    do {
+      word_res_it.forward();
+    } while (word_res_it.data()->part_of_combo);
+  } while (!word_res_it.at_first());
+  total_score += prev_word_score;
+  if (prev_word_done) {
+    done_word_count++;
+  }
+  if (done_word_count == word_count) {
+    return PERFECT_WERDS;
+  } else {
+    return total_score;
+  }
+}
+
+bool Tesseract::digit_or_numeric_punct(WERD_RES *word, int char_position) {
+  int i;
+  int offset;
+
+  for (i = 0, offset = 0; i < char_position; offset += word->best_choice->unichar_lengths()[i++]) {
+    ;
+  }
+  return (
+      word->uch_set->get_isdigit(word->best_choice->unichar_string().c_str() + offset,
+                                 word->best_choice->unichar_lengths()[i]) ||
+      (word->best_choice->permuter() == NUMBER_PERM &&
+       numeric_punctuation.contains(word->best_choice->unichar_string().c_str()[offset])));
+}
+
+/**
+ * @name transform_to_next_perm()
+ * Examines the current word list to find the smallest word gap size. Then walks
+ * the word list closing any gaps of this size by either inserted new
+ * combination words, or extending existing ones.
+ *
+ * The routine COULD be limited to stop it building words longer than N blobs.
+ *
+ * If there are no more gaps then it DELETES the entire list and returns the
+ * empty list to cause termination.
+ */
+void transform_to_next_perm(WERD_RES_LIST &words) {
+  WERD_RES_IT word_it(&words);
+  WERD_RES_IT prev_word_it(&words);
+  WERD_RES *word;
+  WERD_RES *prev_word;
+  int16_t prev_right = -INT16_MAX;
+  TBOX box;
+  int16_t gap;
+  int16_t min_gap = INT16_MAX;
+
+  for (word_it.mark_cycle_pt(); !word_it.cycled_list(); word_it.forward()) {
+    word = word_it.data();
+    if (!word->part_of_combo) {
+      box = word->word->bounding_box();
+      if (prev_right > -INT16_MAX) {
+        gap = box.left() - prev_right;
+        if (gap < min_gap) {
+          min_gap = gap;
+        }
+      }
+      prev_right = box.right();
+    }
+  }
+  if (min_gap < INT16_MAX) {
+    prev_right = -INT16_MAX; // back to start
+    word_it.set_to_list(&words);
+    // Note: we can't use cycle_pt due to inserted combos at start of list.
+    for (; (prev_right == -INT16_MAX) || !word_it.at_first(); word_it.forward()) {
+      word = word_it.data();
+      if (!word->part_of_combo) {
+        box = word->word->bounding_box();
+        if (prev_right > -INT16_MAX) {
+          gap = box.left() - prev_right;
+          if (gap <= min_gap) {
+            prev_word = prev_word_it.data();
+            WERD_RES *combo;
+            if (prev_word->combination) {
+              combo = prev_word;
+            } else {
+              /* Make a new combination and insert before
+               * the first word being joined. */
+              auto *copy_word = new WERD;
+              *copy_word = *(prev_word->word);
+              // deep copy
+              combo = new WERD_RES(copy_word);
+              combo->combination = true;
+              combo->x_height = prev_word->x_height;
+              prev_word->part_of_combo = true;
+              prev_word_it.add_before_then_move(combo);
+            }
+            combo->word->set_flag(W_EOL, word->word->flag(W_EOL));
+            if (word->combination) {
+              combo->word->join_on(word->word);
+              // Move blobs to combo
+              // old combo no longer needed
+              delete word_it.extract();
+            } else {
+              // Copy current wd to combo
+              combo->copy_on(word);
+              word->part_of_combo = true;
+            }
+            combo->done = false;
+            combo->ClearResults();
+          } else {
+            prev_word_it = word_it; // catch up
+          }
+        }
+        prev_right = box.right();
+      }
+    }
+  } else {
+    words.clear(); // signal termination
+  }
+}
+
+void Tesseract::dump_words(WERD_RES_LIST &perm, int16_t score, int16_t mode, bool improved) {
+  WERD_RES_IT word_res_it(&perm);
+
+  if (debug_fix_space_level > 0) {
+    if (mode == 1) {
+      stats_.dump_words_str = "";
+      for (word_res_it.mark_cycle_pt(); !word_res_it.cycled_list(); word_res_it.forward()) {
+        if (!word_res_it.data()->part_of_combo) {
+          stats_.dump_words_str += word_res_it.data()->best_choice->unichar_string();
+          stats_.dump_words_str += ' ';
+        }
+      }
+    }
+
+    if (debug_fix_space_level > 1) {
+      switch (mode) {
+        case 1:
+          tprintf("EXTRACTED (%d): \"", score);
+          break;
+        case 2:
+          tprintf("TESTED (%d): \"", score);
+          break;
+        case 3:
+          tprintf("RETURNED (%d): \"", score);
+          break;
+      }
+
+      for (word_res_it.mark_cycle_pt(); !word_res_it.cycled_list(); word_res_it.forward()) {
+        if (!word_res_it.data()->part_of_combo) {
+          tprintf("%s/%1d ", word_res_it.data()->best_choice->unichar_string().c_str(),
+                  static_cast<int>(word_res_it.data()->best_choice->permuter()));
+        }
+      }
+      tprintf("\"\n");
+    } else if (improved) {
+      tprintf("FIX SPACING \"%s\" => \"", stats_.dump_words_str.c_str());
+      for (word_res_it.mark_cycle_pt(); !word_res_it.cycled_list(); word_res_it.forward()) {
+        if (!word_res_it.data()->part_of_combo) {
+          tprintf("%s/%1d ", word_res_it.data()->best_choice->unichar_string().c_str(),
+                  static_cast<int>(word_res_it.data()->best_choice->permuter()));
+        }
+      }
+      tprintf("\"\n");
+    }
+  }
+}
+
+bool Tesseract::fixspace_thinks_word_done(WERD_RES *word) {
+  if (word->done) {
+    return true;
+  }
+
+  /*
+  Use all the standard pass 2 conditions for mode 5 in set_done() in
+  reject.c BUT DON'T REJECT IF THE WERD IS AMBIGUOUS - FOR SPACING WE DON'T
+  CARE WHETHER WE HAVE of/at on/an etc.
+*/
+  if (fixsp_done_mode > 0 &&
+      (word->tess_accepted || (fixsp_done_mode == 2 && word->reject_map.reject_count() == 0) ||
+       fixsp_done_mode == 3) &&
+      (strchr(word->best_choice->unichar_string().c_str(), ' ') == nullptr) &&
+      ((word->best_choice->permuter() == SYSTEM_DAWG_PERM) ||
+       (word->best_choice->permuter() == FREQ_DAWG_PERM) ||
+       (word->best_choice->permuter() == USER_DAWG_PERM) ||
+       (word->best_choice->permuter() == NUMBER_PERM))) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+/**
+ * @name fix_sp_fp_word()
+ * Test the current word to see if it can be split by deleting noise blobs. If
+ * so, do the business.
+ * Return with the iterator pointing to the same place if the word is unchanged,
+ * or the last of the replacement words.
+ */
+void Tesseract::fix_sp_fp_word(WERD_RES_IT &word_res_it, ROW *row, BLOCK *block) {
+  WERD_RES *word_res;
+  WERD_RES_LIST sub_word_list;
+  WERD_RES_IT sub_word_list_it(&sub_word_list);
+  int16_t new_length;
+  float junk;
+
+  word_res = word_res_it.data();
+  if (word_res->word->flag(W_REP_CHAR) || word_res->combination || word_res->part_of_combo ||
+      !word_res->word->flag(W_DONT_CHOP)) {
+    return;
+  }
+
+  auto blob_index = worst_noise_blob(word_res, &junk);
+  if (blob_index < 0) {
+    return;
+  }
+
+  if (debug_fix_space_level > 1) {
+    tprintf("FP fixspace working on \"%s\"\n", word_res->best_choice->unichar_string().c_str());
+  }
+  word_res->word->rej_cblob_list()->sort(c_blob_comparator);
+  sub_word_list_it.add_after_stay_put(word_res_it.extract());
+  fix_noisy_space_list(sub_word_list, row, block);
+  new_length = sub_word_list.length();
+  word_res_it.add_list_before(&sub_word_list);
+  for (; !word_res_it.at_last() && new_length > 1; new_length--) {
+    word_res_it.forward();
+  }
+}
+
+void Tesseract::fix_noisy_space_list(WERD_RES_LIST &best_perm, ROW *row, BLOCK *block) {
+  int16_t best_score;
+  WERD_RES_IT best_perm_it(&best_perm);
+  WERD_RES_LIST current_perm;
+  WERD_RES_IT current_perm_it(&current_perm);
+  WERD_RES *old_word_res;
+  int16_t current_score;
+  bool improved = false;
+
+  best_score = fp_eval_word_spacing(best_perm); // default score
+
+  dump_words(best_perm, best_score, 1, improved);
+
+  old_word_res = best_perm_it.data();
+  // Even deep_copy doesn't copy the underlying WERD unless its combination
+  // flag is true!.
+  old_word_res->combination = true; // Kludge to force deep copy
+  current_perm_it.add_to_end(WERD_RES::deep_copy(old_word_res));
+  old_word_res->combination = false; // Undo kludge
+
+  break_noisiest_blob_word(current_perm);
+
+  while (best_score != PERFECT_WERDS && !current_perm.empty()) {
+    match_current_words(current_perm, row, block);
+    current_score = fp_eval_word_spacing(current_perm);
+    dump_words(current_perm, current_score, 2, improved);
+    if (current_score > best_score) {
+      best_perm.clear();
+      best_perm.deep_copy(&current_perm, &WERD_RES::deep_copy);
+      best_score = current_score;
+      improved = true;
+    }
+    if (current_score < PERFECT_WERDS) {
+      break_noisiest_blob_word(current_perm);
+    }
+  }
+  dump_words(best_perm, best_score, 3, improved);
+}
+
+/**
+ * break_noisiest_blob_word()
+ * Find the word with the blob which looks like the worst noise.
+ * Break the word into two, deleting the noise blob.
+ */
+void Tesseract::break_noisiest_blob_word(WERD_RES_LIST &words) {
+  WERD_RES_IT word_it(&words);
+  WERD_RES_IT worst_word_it;
+  float worst_noise_score = 9999;
+  int worst_blob_index = -1; // Noisiest blob of noisiest wd
+  float noise_score;         // of wds noisiest blob
+  WERD_RES *word_res;
+  C_BLOB_IT blob_it;
+  C_BLOB_IT rej_cblob_it;
+  C_BLOB_LIST new_blob_list;
+  C_BLOB_IT new_blob_it;
+  C_BLOB_IT new_rej_cblob_it;
+  WERD *new_word;
+  int16_t start_of_noise_blob;
+  int16_t i;
+
+  for (word_it.mark_cycle_pt(); !word_it.cycled_list(); word_it.forward()) {
+    auto blob_index = worst_noise_blob(word_it.data(), &noise_score);
+    if (blob_index > -1 && worst_noise_score > noise_score) {
+      worst_noise_score = noise_score;
+      worst_blob_index = blob_index;
+      worst_word_it = word_it;
+    }
+  }
+  if (worst_blob_index < 0) {
+    words.clear(); // signal termination
+    return;
+  }
+
+  /* Now split the worst_word_it */
+
+  word_res = worst_word_it.data();
+
+  /* Move blobs before noise blob to a new bloblist */
+
+  new_blob_it.set_to_list(&new_blob_list);
+  blob_it.set_to_list(word_res->word->cblob_list());
+  for (i = 0; i < worst_blob_index; i++, blob_it.forward()) {
+    new_blob_it.add_after_then_move(blob_it.extract());
+  }
+  start_of_noise_blob = blob_it.data()->bounding_box().left();
+  delete blob_it.extract(); // throw out noise blob
+
+  new_word = new WERD(&new_blob_list, word_res->word);
+  new_word->set_flag(W_EOL, false);
+  word_res->word->set_flag(W_BOL, false);
+  word_res->word->set_blanks(1); // After break
+
+  new_rej_cblob_it.set_to_list(new_word->rej_cblob_list());
+  rej_cblob_it.set_to_list(word_res->word->rej_cblob_list());
+  for (; (!rej_cblob_it.empty() &&
+          (rej_cblob_it.data()->bounding_box().left() < start_of_noise_blob));
+       rej_cblob_it.forward()) {
+    new_rej_cblob_it.add_after_then_move(rej_cblob_it.extract());
+  }
+
+  auto *new_word_res = new WERD_RES(new_word);
+  new_word_res->combination = true;
+  worst_word_it.add_before_then_move(new_word_res);
+
+  word_res->ClearResults();
+}
+
+int16_t Tesseract::worst_noise_blob(WERD_RES *word_res, float *worst_noise_score) {
+  float noise_score[512];
+  int min_noise_blob; // 1st contender
+  int max_noise_blob; // last contender
+  int non_noise_count;
+  int worst_noise_blob; // Worst blob
+  float small_limit = kBlnXHeight * fixsp_small_outlines_size;
+  float non_noise_limit = kBlnXHeight * 0.8;
+
+  if (word_res->rebuild_word == nullptr) {
+    return -1; // Can't handle cube words.
+  }
+
+  // Normalised.
+  auto blob_count = word_res->box_word->length();
+  ASSERT_HOST(blob_count <= 512);
+  if (blob_count < 5) {
+    return -1; // too short to split
+  }
+
+    /* Get the noise scores for all blobs */
+
+#ifndef SECURE_NAMES
+  if (debug_fix_space_level > 5) {
+    tprintf("FP fixspace Noise metrics for \"%s\": ",
+            word_res->best_choice->unichar_string().c_str());
+  }
+#endif
+
+  for (unsigned i = 0; i < blob_count && i < word_res->rebuild_word->NumBlobs(); i++) {
+    TBLOB *blob = word_res->rebuild_word->blobs[i];
+    if (word_res->reject_map[i].accepted()) {
+      noise_score[i] = non_noise_limit;
+    } else {
+      noise_score[i] = blob_noise_score(blob);
+    }
+
+    if (debug_fix_space_level > 5) {
+      tprintf("%1.1f ", noise_score[i]);
+    }
+  }
+  if (debug_fix_space_level > 5) {
+    tprintf("\n");
+  }
+
+  /* Now find the worst one which is far enough away from the end of the word */
+
+  non_noise_count = 0;
+  int i;
+  for (i = 0; static_cast<unsigned>(i) < blob_count && non_noise_count < fixsp_non_noise_limit; i++) {
+    if (noise_score[i] >= non_noise_limit) {
+      non_noise_count++;
+    }
+  }
+  if (non_noise_count < fixsp_non_noise_limit) {
+    return -1;
+  }
+
+  min_noise_blob = i;
+
+  non_noise_count = 0;
+  for (i = blob_count - 1; i >= 0 && non_noise_count < fixsp_non_noise_limit; i--) {
+    if (noise_score[i] >= non_noise_limit) {
+      non_noise_count++;
+    }
+  }
+  if (non_noise_count < fixsp_non_noise_limit) {
+    return -1;
+  }
+
+  max_noise_blob = i;
+
+  if (min_noise_blob > max_noise_blob) {
+    return -1;
+  }
+
+  *worst_noise_score = small_limit;
+  worst_noise_blob = -1;
+  for (auto i = min_noise_blob; i <= max_noise_blob; i++) {
+    if (noise_score[i] < *worst_noise_score) {
+      worst_noise_blob = i;
+      *worst_noise_score = noise_score[i];
+    }
+  }
+  return worst_noise_blob;
+}
+
+float Tesseract::blob_noise_score(TBLOB *blob) {
+  TBOX box; // BB of outline
+  int16_t outline_count = 0;
+  int16_t max_dimension;
+  int16_t largest_outline_dimension = 0;
+
+  for (TESSLINE *ol = blob->outlines; ol != nullptr; ol = ol->next) {
+    outline_count++;
+    box = ol->bounding_box();
+    if (box.height() > box.width()) {
+      max_dimension = box.height();
+    } else {
+      max_dimension = box.width();
+    }
+
+    if (largest_outline_dimension < max_dimension) {
+      largest_outline_dimension = max_dimension;
+    }
+  }
+
+  if (outline_count > 5) {
+    // penalise LOTS of blobs
+    largest_outline_dimension *= 2;
+  }
+
+  box = blob->bounding_box();
+  if (box.bottom() > kBlnBaselineOffset * 4 || box.top() < kBlnBaselineOffset / 2) {
+    // Lax blob is if high or low
+    largest_outline_dimension /= 2;
+  }
+
+  return largest_outline_dimension;
+}
+
+void fixspace_dbg(WERD_RES *word) {
+  TBOX box = word->word->bounding_box();
+  const bool show_map_detail = false;
+
+  box.print();
+  tprintf(" \"%s\" ", word->best_choice->unichar_string().c_str());
+  tprintf("Blob count: %d (word); %d/%d (rebuild word)\n", word->word->cblob_list()->length(),
+          word->rebuild_word->NumBlobs(), word->box_word->length());
+  word->reject_map.print(debug_fp);
+  tprintf("\n");
+  if (show_map_detail) {
+    tprintf("\"%s\"\n", word->best_choice->unichar_string().c_str());
+    for (unsigned i = 0; word->best_choice->unichar_string()[i] != '\0'; i++) {
+      tprintf("**** \"%c\" ****\n", word->best_choice->unichar_string()[i]);
+      word->reject_map[i].full_print(debug_fp);
+    }
+  }
+
+  tprintf("Tess Accepted: %s\n", word->tess_accepted ? "TRUE" : "FALSE");
+  tprintf("Done flag: %s\n\n", word->done ? "TRUE" : "FALSE");
+}
+
+/**
+ * fp_eval_word_spacing()
+ * Evaluation function for fixed pitch word lists.
+ *
+ * Basically, count the number of "nice" characters - those which are in tess
+ * acceptable words or in dict words and are not rejected.
+ * Penalise any potential noise chars
+ */
+int16_t Tesseract::fp_eval_word_spacing(WERD_RES_LIST &word_res_list) {
+  WERD_RES_IT word_it(&word_res_list);
+  WERD_RES *word;
+  int16_t score = 0;
+  float small_limit = kBlnXHeight * fixsp_small_outlines_size;
+
+  for (word_it.mark_cycle_pt(); !word_it.cycled_list(); word_it.forward()) {
+    word = word_it.data();
+    if (word->rebuild_word == nullptr) {
+      continue; // Can't handle cube words.
+    }
+    if (word->done || word->tess_accepted || word->best_choice->permuter() == SYSTEM_DAWG_PERM ||
+        word->best_choice->permuter() == FREQ_DAWG_PERM ||
+        word->best_choice->permuter() == USER_DAWG_PERM || safe_dict_word(word) > 0) {
+      auto num_blobs = word->rebuild_word->NumBlobs();
+      UNICHAR_ID space = word->uch_set->unichar_to_id(" ");
+      for (unsigned i = 0; i < word->best_choice->length() && i < num_blobs; ++i) {
+        TBLOB *blob = word->rebuild_word->blobs[i];
+        if (word->best_choice->unichar_id(i) == space || blob_noise_score(blob) < small_limit) {
+          score -= 1; // penalise possibly erroneous non-space
+        } else if (word->reject_map[i].accepted()) {
+          score++;
+        }
+      }
+    }
+  }
+  if (score < 0) {
+    score = 0;
+  }
+  return score;
+}
+
+} // namespace tesseract