Ejemplo n.º 1
0
// Creates a fake blob choice from the combination of the given fragments.
// unichar is the class to be made from the combination,
// expanded_fragment_lengths[choice_index] is the number of fragments to use.
// old_choices[choice_index] has the classifier output for each fragment.
// choice index initially indexes the last fragment and should be decremented
// expanded_fragment_lengths[choice_index] times to get the earlier fragments.
// Guarantees to return something non-null, or abort!
BLOB_CHOICE* Wordrec::rebuild_fragments(
    const char* unichar,
    const char* expanded_fragment_lengths,
    int choice_index,
    BLOB_CHOICE_LIST_VECTOR *old_choices) {
  float rating = 0.0f;
  float certainty = 0.0f;
  inT16 min_xheight = -MAX_INT16;
  inT16 max_xheight = MAX_INT16;
  for (int fragment_pieces = expanded_fragment_lengths[choice_index] - 1;
       fragment_pieces >= 0; --fragment_pieces, --choice_index) {
    // Get a pointer to the classifier results from the old_choices.
    BLOB_CHOICE_LIST *current_choices = old_choices->get(choice_index);
    // Populate fragment with updated values and look for the
    // fragment with the same values in current_choices.
    // Update rating and certainty of the character being composed.
    CHAR_FRAGMENT fragment;
    fragment.set_all(unichar, fragment_pieces,
                     expanded_fragment_lengths[choice_index], false);
    BLOB_CHOICE_IT choice_it(current_choices);
    for (choice_it.mark_cycle_pt(); !choice_it.cycled_list();
        choice_it.forward()) {
      BLOB_CHOICE* choice = choice_it.data();
      const CHAR_FRAGMENT *current_fragment =
          getDict().getUnicharset().get_fragment(choice->unichar_id());
      if (current_fragment && fragment.equals(current_fragment)) {
        rating += choice->rating();
        if (choice->certainty() < certainty) {
          certainty = choice->certainty();
        }
        IntersectRange(choice->min_xheight(), choice->max_xheight(),
                       &min_xheight, &max_xheight);
        break;
      }
    }
    if (choice_it.cycled_list()) {
      print_ratings_list("Failure", current_choices, unicharset);
      tprintf("Failed to find fragment %s at index=%d\n",
              fragment.to_string().string(), choice_index);
    }
    ASSERT_HOST(!choice_it.cycled_list());  // Be sure we found the fragment.
  }
  return new BLOB_CHOICE(getDict().getUnicharset().unichar_to_id(unichar),
                         rating, certainty, -1, -1, 0,
                         min_xheight, max_xheight, false);
}
Ejemplo n.º 2
0
/**
 * rebuild_current_state
 *
 * Evaluate the segmentation that is represented by this state in the
 * best first search.  Add this state to the "states_seen" list.
 */
BLOB_CHOICE_LIST_VECTOR *Wordrec::rebuild_current_state(
    TBLOB *blobs,
    SEAMS seam_list,
    STATE *state,
    BLOB_CHOICE_LIST_VECTOR *old_choices,
    int fx,
    bool force_rebuild,
    const WERD_CHOICE &best_choice,
    const MATRIX *ratings) {
  // Initialize search_state, num_joints, x, y.
  int num_joints = array_count(seam_list);
#ifndef GRAPHICS_DISABLED
    if (wordrec_display_segmentations) {
      print_state("Rebuiling state", state, num_joints);
    }
#endif
  SEARCH_STATE search_state = bin_to_chunks(state, num_joints);
  int x = 0;
  int y;
  int i;
  for (i = 1; i <= search_state[0]; i++) {
    y = x + search_state[i];
    x = y + 1;
  }
  y = count_blobs (blobs) - 1;

  // Initialize char_choices, expanded_fragment_lengths:
  // e.g. if fragment_lengths = {1 1 2 3 1},
  // expanded_fragment_lengths_str = {1 1 2 2 3 3 3 1}.
  BLOB_CHOICE_LIST_VECTOR *char_choices = new BLOB_CHOICE_LIST_VECTOR();
  STRING expanded_fragment_lengths_str = "";
  bool state_has_fragments = false;
  const char *fragment_lengths = NULL;

  if (best_choice.length() > 0) {
    fragment_lengths = best_choice.fragment_lengths();
  }
  if (fragment_lengths) {
    for (int i = 0; i < best_choice.length(); ++i) {
      *char_choices += NULL;
      if (fragment_lengths[i] > 1) {
        state_has_fragments = true;
      }
      for (int j = 0; j < fragment_lengths[i]; ++j) {
        expanded_fragment_lengths_str += fragment_lengths[i];
      }
    }
  } else {
    for (i = 0; i <= search_state[0]; ++i) {
      expanded_fragment_lengths_str += (char)1;
      *char_choices += NULL;
    }
  }

  // Finish early if force_rebuld is false and there are no fragments to merge.
  if (!force_rebuild && !state_has_fragments) {
    delete char_choices;
    memfree(search_state);
    return old_choices;
  }

  // Set up variables for concatenating fragments.
  const char *word_lengths_ptr = NULL;
  const char *word_ptr = NULL;
  if (state_has_fragments) {
    // Make word_lengths_ptr point to the last element in
    // best_choice->unichar_lengths().
    word_lengths_ptr = best_choice.unichar_lengths().string();
    word_lengths_ptr += (strlen(word_lengths_ptr)-1);
    // Make word_str point to the beginning of the last
    // unichar in best_choice->unichar_string().
    word_ptr = best_choice.unichar_string().string();
    word_ptr += (strlen(word_ptr)-*word_lengths_ptr);
  }
  const char *expanded_fragment_lengths =
    expanded_fragment_lengths_str.string();
  bool merging_fragment = false;
  int true_y = -1;
  char unichar[UNICHAR_LEN + 1];
  int fragment_pieces = -1;
  float rating = 0.0;
  float certainty = -MAX_FLOAT32;

  // Populate char_choices list such that it corresponds to search_state.
  //
  // If we are rebuilding a state that contains character fragments:
  // -- combine blobs that belong to character fragments
  // -- re-classify the blobs to obtain choices list for the merged blob
  // -- ensure that correct classification appears in the new choices list
  //    NOTE: a choice composed form original fragment choices will be always
  //    added to the new choices list for each character composed from
  //    fragments (even if the choice for the corresponding character appears
  //    in the re-classified choices list of for the newly merged blob).
  BLOB_CHOICE_IT temp_it;
  int char_choices_index = char_choices->length() - 1;
  for (i = search_state[0]; i >= 0; i--) {
    BLOB_CHOICE_LIST *current_choices = join_blobs_and_classify(
        blobs, seam_list, x, y, fx, ratings, old_choices);
    // Combine character fragments.
    if (expanded_fragment_lengths[i] > 1) {
      // Start merging character fragments.
      if (!merging_fragment) {
        merging_fragment = true;
        true_y = y;
        fragment_pieces = expanded_fragment_lengths[i];
        rating = 0.0;
        certainty = -MAX_FLOAT32;
        strncpy(unichar, word_ptr, *word_lengths_ptr);
        unichar[*word_lengths_ptr] = '\0';
      }
      // Take into account the fact that we could have joined pieces
      // since we first recorded the ending point of a fragment (true_y).
      true_y -= y - x;
      // Populate fragment with updated values and look for the
      // fragment with the same values in current_choices.
      // Update rating and certainty of the character being composed.
      fragment_pieces--;
      CHAR_FRAGMENT fragment;
      fragment.set_all(unichar, fragment_pieces,
                       expanded_fragment_lengths[i]);
      temp_it.set_to_list(current_choices);
      for (temp_it.mark_cycle_pt(); !temp_it.cycled_list();
           temp_it.forward()) {
        const CHAR_FRAGMENT *current_fragment =
          getDict().getUnicharset().get_fragment(temp_it.data()->unichar_id());
        if (current_fragment && fragment.equals(current_fragment)) {
          rating += temp_it.data()->rating();
          if (temp_it.data()->certainty() > certainty) {
            certainty = temp_it.data()->certainty();
          }
          break;
        }
      }
      assert(!temp_it.cycled_list());  // make sure we found the fragment
      // Free current_choices for the fragmented character.
      delete current_choices;

      // Finish composing character from fragments.
      if (fragment_pieces == 0) {
        // Populate current_choices with the classification of
        // the blob merged from blobs of each character fragment.
        current_choices = join_blobs_and_classify(blobs, seam_list, x,
                                                  true_y, fx, ratings, NULL);
        BLOB_CHOICE *merged_choice =
          new BLOB_CHOICE(getDict().getUnicharset().unichar_to_id(unichar),
                          rating, certainty, 0, NO_PERM);

        // Insert merged_blob into current_choices, such that current_choices
        // are still sorted in non-descending order by rating.
        ASSERT_HOST(!current_choices->empty());
        temp_it.set_to_list(current_choices);
        for (temp_it.mark_cycle_pt();
             !temp_it.cycled_list() &&
             merged_choice->rating() > temp_it.data()->rating();
             temp_it.forward());
        temp_it.add_before_stay_put(merged_choice);

        // Done merging this fragmented character.
        merging_fragment = false;
      }
    }
    if (!merging_fragment) {
      // Get rid of fragments in current_choices.
      temp_it.set_to_list(current_choices);
      for (temp_it.mark_cycle_pt(); !temp_it.cycled_list();
           temp_it.forward()) {
        if (getDict().getUnicharset().get_fragment(
            temp_it.data()->unichar_id())) {
          delete temp_it.extract();
        }
      }
      char_choices->set(current_choices, char_choices_index);
      char_choices_index--;

      // Update word_ptr and word_lengths_ptr.
      if (word_lengths_ptr != NULL && word_ptr != NULL) {
        word_lengths_ptr--;
        word_ptr -= (*word_lengths_ptr);
      }
    }
    y = x - 1;
    x = y - search_state[i];
  }
  old_choices->delete_data_pointers();
  delete old_choices;
  memfree(search_state);

  return (char_choices);
}