tesseract-ocr/classify/speckle.cpp

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/******************************************************************************
 **     Filename:    speckle.c
 **     Purpose:     Routines used by classifier to filter out speckle.
 **     Author:      Dan Johnson
 **     History:     Mon Mar 11 10:06:14 1991, DSJ, Created.
 **
 **     (c) Copyright Hewlett-Packard Company, 1988.
 ** 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 Files and Type Defines
-----------------------------------------------------------------------------*/
#include "speckle.h"

#include "blobs.h"
#include "ratngs.h"
#include "params.h"

/*-----------------------------------------------------------------------------
        Global Data Definitions and Declarations
-----------------------------------------------------------------------------*/
double_VAR(speckle_large_max_size, 0.30, "Max large speckle size");

double_VAR(speckle_small_penalty, 10.0, "Small speckle penalty");

double_VAR(speckle_large_penalty, 10.0, "Large speckle penalty");

double_VAR(speckle_small_certainty, -1.0, "Small speckle certainty");

/*-----------------------------------------------------------------------------
              Public Code
-----------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
void AddLargeSpeckleTo(BLOB_CHOICE_LIST *Choices) {
  assert(Choices != NULL);
  BLOB_CHOICE *blob_choice;
  BLOB_CHOICE_IT temp_it;
  temp_it.set_to_list(Choices);

  // If there are no other choices, use the small speckle penalty plus
  // the large speckle penalty.
  if (Choices->length() == 0) {
    blob_choice =
      new BLOB_CHOICE(0, speckle_small_certainty + speckle_large_penalty,
                      speckle_small_certainty, -1, -1, NULL, 0, 0, false);
    temp_it.add_to_end(blob_choice);
    return;
  }

  // If there are other choices,  add a null choice that is slightly worse
  // than the worst choice so far.
  temp_it.move_to_last();
  blob_choice = temp_it.data();  // pick the worst choice
  temp_it.add_to_end(
      new BLOB_CHOICE(0, blob_choice->rating() + speckle_large_penalty,
                      blob_choice->certainty(), -1, -1, NULL, 0, 0, false));
}                                /* AddLargeSpeckleTo */


/*---------------------------------------------------------------------------*/
BOOL8 LargeSpeckle(TBLOB *blob) {
  double speckle_size = BASELINE_SCALE * speckle_large_max_size;
  TBOX bbox = blob->bounding_box();
  return (bbox.width() < speckle_size && bbox.height() < speckle_size);
}                                /* LargeSpeckle */