tesseract/ccstruct/seam.cpp

541 lines
16 KiB
C++

/* -*-C-*-
********************************************************************************
*
* File: seam.c (Formerly seam.c)
* Description:
* Author: Mark Seaman, OCR Technology
* Created: Fri Oct 16 14:37:00 1987
* Modified: Fri May 17 16:30:13 1991 (Mark Seaman) marks@hpgrlt
* Language: C
* Package: N/A
* Status: Reusable Software Component
*
* (c) Copyright 1987, Hewlett-Packard Company.
** 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.
*
*********************************************************************************/
/*----------------------------------------------------------------------
I n c l u d e s
----------------------------------------------------------------------*/
#include "seam.h"
#include "blobs.h"
#include "freelist.h"
#include "tprintf.h"
#ifdef __UNIX__
#include <assert.h>
#endif
/*----------------------------------------------------------------------
V a r i a b l e s
----------------------------------------------------------------------*/
#define NUM_STARTING_SEAMS 20
/*----------------------------------------------------------------------
Public Function Code
----------------------------------------------------------------------*/
/**
* @name point_in_split
*
* Check to see if either of these points are present in the current
* split.
* @returns TRUE if one of them is split.
*/
bool point_in_split(SPLIT *split, EDGEPT *point1, EDGEPT *point2) {
return ((split) ? ((exact_point (split->point1, point1) ||
exact_point (split->point1, point2) ||
exact_point (split->point2, point1) ||
exact_point (split->point2, point2)) ? TRUE : FALSE)
: FALSE);
}
/**
* @name point_in_seam
*
* Check to see if either of these points are present in the current
* seam.
* @returns TRUE if one of them is.
*/
bool point_in_seam(const SEAM *seam, SPLIT *split) {
return (point_in_split(seam->split1, split->point1, split->point2) ||
point_in_split(seam->split2, split->point1, split->point2) ||
point_in_split(seam->split3, split->point1, split->point2));
}
/**
* @name point_used_by_split
*
* Return whether this particular EDGEPT * is used in a given split.
* @returns TRUE if the edgept is used by the split.
*/
bool point_used_by_split(SPLIT *split, EDGEPT *point) {
if (split == NULL) return false;
return point == split->point1 || point == split->point2;
}
/**
* @name point_used_by_seam
*
* Return whether this particular EDGEPT * is used in a given seam.
* @returns TRUE if the edgept is used by the seam.
*/
bool point_used_by_seam(SEAM *seam, EDGEPT *point) {
if (seam == NULL) return false;
return point_used_by_split(seam->split1, point) ||
point_used_by_split(seam->split2, point) ||
point_used_by_split(seam->split3, point);
}
/**
* @name combine_seam
*
* Combine two seam records into a single seam. Move the split
* references from the second seam to the first one. The argument
* convention is patterned after strcpy.
*/
void combine_seams(SEAM *dest_seam, SEAM *source_seam) {
dest_seam->priority += source_seam->priority;
dest_seam->location += source_seam->location;
dest_seam->location /= 2;
if (source_seam->split1) {
if (!dest_seam->split1)
dest_seam->split1 = source_seam->split1;
else if (!dest_seam->split2)
dest_seam->split2 = source_seam->split1;
else if (!dest_seam->split3)
dest_seam->split3 = source_seam->split1;
else
delete source_seam->split1; // Wouldn't have fitted.
source_seam->split1 = NULL;
}
if (source_seam->split2) {
if (!dest_seam->split2)
dest_seam->split2 = source_seam->split2;
else if (!dest_seam->split3)
dest_seam->split3 = source_seam->split2;
else
delete source_seam->split2; // Wouldn't have fitted.
source_seam->split2 = NULL;
}
if (source_seam->split3) {
if (!dest_seam->split3)
dest_seam->split3 = source_seam->split3;
else
delete source_seam->split3; // Wouldn't have fitted.
source_seam->split3 = NULL;
}
delete source_seam;
}
/**
* @name start_seam_list
*
* Initialize a list of seams that match the original number of blobs
* present in the starting segmentation. Each of the seams created
* by this routine have location information only.
*/
void start_seam_list(TWERD *word, GenericVector<SEAM*>* seam_array) {
seam_array->truncate(0);
TPOINT location;
for (int b = 1; b < word->NumBlobs(); ++b) {
TBOX bbox = word->blobs[b - 1]->bounding_box();
TBOX nbox = word->blobs[b]->bounding_box();
location.x = (bbox.right() + nbox.left()) / 2;
location.y = (bbox.bottom() + bbox.top() + nbox.bottom() + nbox.top()) / 4;
seam_array->push_back(new SEAM(0.0f, location, NULL, NULL, NULL));
}
}
/**
* @name test_insert_seam
*
* @returns true if insert_seam will succeed.
*/
bool test_insert_seam(const GenericVector<SEAM*>& seam_array,
TWERD *word, int index) {
SEAM *test_seam;
TBLOB *blob;
int test_index;
int list_length;
list_length = seam_array.size();
for (int test_index = 0; test_index < index; ++test_index) {
test_seam = seam_array[test_index];
if (test_index + test_seam->widthp < index &&
test_seam->widthp + test_index == index - 1 &&
account_splits(test_seam, word, test_index + 1, 1) < 0)
return false;
}
for (int test_index = index; test_index < list_length; test_index++) {
test_seam = seam_array[test_index];
if (test_index - test_seam->widthn >= index &&
test_index - test_seam->widthn == index &&
account_splits(test_seam, word, test_index + 1, -1) < 0)
return false;
}
return true;
}
/**
* @name insert_seam
*
* Add another seam to a collection of seams at a particular location
* in the seam array.
*/
void insert_seam(const TWERD* word, int index, SEAM *seam,
GenericVector<SEAM*>* seam_array) {
SEAM *test_seam;
int test_index;
int list_length;
list_length = seam_array->size();
for (int test_index = 0; test_index < index; ++test_index) {
test_seam = seam_array->get(test_index);
if (test_index + test_seam->widthp >= index) {
test_seam->widthp++; /*got in the way */
} else if (test_seam->widthp + test_index == index - 1) {
test_seam->widthp = account_splits(test_seam, word, test_index + 1, 1);
if (test_seam->widthp < 0) {
tprintf("Failed to find any right blob for a split!\n");
print_seam("New dud seam", seam);
print_seam("Failed seam", test_seam);
}
}
}
for (int test_index = index; test_index < list_length; test_index++) {
test_seam = seam_array->get(test_index);
if (test_index - test_seam->widthn < index) {
test_seam->widthn++; /*got in the way */
} else if (test_index - test_seam->widthn == index) {
test_seam->widthn = account_splits(test_seam, word, test_index + 1, -1);
if (test_seam->widthn < 0) {
tprintf("Failed to find any left blob for a split!\n");
print_seam("New dud seam", seam);
print_seam("Failed seam", test_seam);
}
}
}
seam_array->insert(seam, index);
}
/**
* @name account_splits
*
* Account for all the splits by looking to the right (blob_direction == 1),
* or to the left (blob_direction == -1) in the word.
*/
int account_splits(const SEAM *seam, const TWERD *word, int blob_index,
int blob_direction) {
inT8 found_em[3];
inT8 width;
found_em[0] = seam->split1 == NULL;
found_em[1] = seam->split2 == NULL;
found_em[2] = seam->split3 == NULL;
if (found_em[0] && found_em[1] && found_em[2])
return 0;
width = 0;
do {
TBLOB* blob = word->blobs[blob_index];
if (!found_em[0])
found_em[0] = find_split_in_blob(seam->split1, blob);
if (!found_em[1])
found_em[1] = find_split_in_blob(seam->split2, blob);
if (!found_em[2])
found_em[2] = find_split_in_blob(seam->split3, blob);
if (found_em[0] && found_em[1] && found_em[2]) {
return width;
}
width++;
blob_index += blob_direction;
} while (0 <= blob_index && blob_index < word->NumBlobs());
return -1;
}
/**
* @name find_split_in_blob
*
* @returns TRUE if the split is somewhere in this blob.
*/
bool find_split_in_blob(SPLIT *split, TBLOB *blob) {
TESSLINE *outline;
for (outline = blob->outlines; outline != NULL; outline = outline->next)
if (outline->Contains(split->point1->pos))
break;
if (outline == NULL)
return FALSE;
for (outline = blob->outlines; outline != NULL; outline = outline->next)
if (outline->Contains(split->point2->pos))
return TRUE;
return FALSE;
}
/**
* @name join_two_seams
*
* Merge these two seams into a new seam. Duplicate the split records
* in both of the input seams. Return the resultant seam.
*/
SEAM *join_two_seams(const SEAM *seam1, const SEAM *seam2) {
SEAM *result = NULL;
SEAM *temp;
assert(seam1 &&seam2);
if (((seam1->split3 == NULL && seam2->split2 == NULL) ||
(seam1->split2 == NULL && seam2->split3 == NULL) ||
seam1->split1 == NULL || seam2->split1 == NULL) &&
(!shared_split_points(seam1, seam2))) {
result = new SEAM(*seam1);
temp = new SEAM(*seam2);
combine_seams(result, temp);
}
return (result);
}
/**
* @name print_seam
*
* Print a list of splits. Show the coordinates of both points in
* each split.
*/
void print_seam(const char *label, SEAM *seam) {
if (seam) {
tprintf(label);
tprintf(" %6.2f @ (%d,%d), p=%d, n=%d ",
seam->priority, seam->location.x, seam->location.y,
seam->widthp, seam->widthn);
print_split(seam->split1);
if (seam->split2) {
tprintf(", ");
print_split (seam->split2);
if (seam->split3) {
tprintf(", ");
print_split (seam->split3);
}
}
tprintf("\n");
}
}
/**
* @name print_seams
*
* Print a list of splits. Show the coordinates of both points in
* each split.
*/
void print_seams(const char *label, const GenericVector<SEAM*>& seams) {
char number[CHARS_PER_LINE];
if (!seams.empty()) {
tprintf("%s\n", label);
for (int x = 0; x < seams.size(); ++x) {
sprintf(number, "%2d: ", x);
print_seam(number, seams[x]);
}
tprintf("\n");
}
}
/**
* @name shared_split_points
*
* Check these two seams to make sure that neither of them have two
* points in common. Return TRUE if any of the same points are present
* in any of the splits of both seams.
*/
int shared_split_points(const SEAM *seam1, const SEAM *seam2) {
if (seam1 == NULL || seam2 == NULL)
return (FALSE);
if (seam2->split1 == NULL)
return (FALSE);
if (point_in_seam(seam1, seam2->split1))
return (TRUE);
if (seam2->split2 == NULL)
return (FALSE);
if (point_in_seam(seam1, seam2->split2))
return (TRUE);
if (seam2->split3 == NULL)
return (FALSE);
if (point_in_seam(seam1, seam2->split3))
return (TRUE);
return (FALSE);
}
/**********************************************************************
* break_pieces
*
* Break up the blobs in this chain so that they are all independent.
* This operation should undo the affect of join_pieces.
**********************************************************************/
void break_pieces(const GenericVector<SEAM*>& seams, int first, int last,
TWERD *word) {
for (int x = first; x < last; ++x)
reveal_seam(seams[x]);
TESSLINE *outline = word->blobs[first]->outlines;
int next_blob = first + 1;
while (outline != NULL && next_blob <= last) {
if (outline->next == word->blobs[next_blob]->outlines) {
outline->next = NULL;
outline = word->blobs[next_blob]->outlines;
++next_blob;
} else {
outline = outline->next;
}
}
}
/**********************************************************************
* join_pieces
*
* Join a group of base level pieces into a single blob that can then
* be classified.
**********************************************************************/
void join_pieces(const GenericVector<SEAM*>& seams, int first, int last,
TWERD *word) {
TESSLINE *outline = word->blobs[first]->outlines;
if (!outline)
return;
for (int x = first; x < last; ++x) {
SEAM *seam = seams[x];
if (x - seam->widthn >= first && x + seam->widthp < last)
hide_seam(seam);
while (outline->next)
outline = outline->next;
outline->next = word->blobs[x + 1]->outlines;
}
}
/**********************************************************************
* hide_seam
*
* Change the edge points that are referenced by this seam to make
* them hidden edges.
**********************************************************************/
void hide_seam(SEAM *seam) {
if (seam == NULL || seam->split1 == NULL)
return;
hide_edge_pair (seam->split1->point1, seam->split1->point2);
if (seam->split2 == NULL)
return;
hide_edge_pair (seam->split2->point1, seam->split2->point2);
if (seam->split3 == NULL)
return;
hide_edge_pair (seam->split3->point1, seam->split3->point2);
}
/**********************************************************************
* hide_edge_pair
*
* Change the edge points that are referenced by this seam to make
* them hidden edges.
**********************************************************************/
void hide_edge_pair(EDGEPT *pt1, EDGEPT *pt2) {
EDGEPT *edgept;
edgept = pt1;
do {
edgept->Hide();
edgept = edgept->next;
}
while (!exact_point (edgept, pt2) && edgept != pt1);
if (edgept == pt1) {
/* tprintf("Hid entire outline at (%d,%d)!!\n",
edgept->pos.x,edgept->pos.y); */
}
edgept = pt2;
do {
edgept->Hide();
edgept = edgept->next;
}
while (!exact_point (edgept, pt1) && edgept != pt2);
if (edgept == pt2) {
/* tprintf("Hid entire outline at (%d,%d)!!\n",
edgept->pos.x,edgept->pos.y); */
}
}
/**********************************************************************
* reveal_seam
*
* Change the edge points that are referenced by this seam to make
* them hidden edges.
**********************************************************************/
void reveal_seam(SEAM *seam) {
if (seam == NULL || seam->split1 == NULL)
return;
reveal_edge_pair (seam->split1->point1, seam->split1->point2);
if (seam->split2 == NULL)
return;
reveal_edge_pair (seam->split2->point1, seam->split2->point2);
if (seam->split3 == NULL)
return;
reveal_edge_pair (seam->split3->point1, seam->split3->point2);
}
/**********************************************************************
* reveal_edge_pair
*
* Change the edge points that are referenced by this seam to make
* them hidden edges.
**********************************************************************/
void reveal_edge_pair(EDGEPT *pt1, EDGEPT *pt2) {
EDGEPT *edgept;
edgept = pt1;
do {
edgept->Reveal();
edgept = edgept->next;
}
while (!exact_point (edgept, pt2) && edgept != pt1);
if (edgept == pt1) {
/* tprintf("Hid entire outline at (%d,%d)!!\n",
edgept->pos.x,edgept->pos.y); */
}
edgept = pt2;
do {
edgept->Reveal();
edgept = edgept->next;
}
while (!exact_point (edgept, pt1) && edgept != pt2);
if (edgept == pt2) {
/* tprintf("Hid entire outline at (%d,%d)!!\n",
edgept->pos.x,edgept->pos.y); */
}
}