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git-svn-id: https://tesseract-ocr.googlecode.com/svn/trunk/trunk@2 d0cd1f9f-072b-0410-8dd7-cf729c803f20
811 lines
26 KiB
C++
811 lines
26 KiB
C++
/*****************************************************************************
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*
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* File: blkocc.cpp (Formerly blockocc.c)
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* Description: Block Occupancy routines
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* Author: Chris Newton
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* Created: Fri Nov 8
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* Modified:
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* Language: C++
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* Package: N/A
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* Status: Experimental (Do Not Distribute)
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*
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* (c) Copyright 1991, Hewlett-Packard Company.
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** Licensed under the Apache License, Version 2.0 (the "License");
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** you may not use this file except in compliance with the License.
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** You may obtain a copy of the License at
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** http://www.apache.org/licenses/LICENSE-2.0
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** Unless required by applicable law or agreed to in writing, software
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** distributed under the License is distributed on an "AS IS" BASIS,
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** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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** See the License for the specific language governing permissions and
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** limitations under the License.
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*
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******************************************************************************/
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/*
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----------------------------------------------------------------------
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I n c l u d e s
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----------------------------------------------------------------------
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*/
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#include "mfcpch.h"
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#include <ctype.h>
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#include <math.h>
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#include "errcode.h"
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#include "grphics.h"
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#include "drawtord.h"
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#include "blkocc.h"
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#include "notdll.h"
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const ERRCODE BLOCKOCC = "BlockOcc";
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ELISTIZE (REGION_OCC)
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#define EXTERN
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EXTERN BOOL_VAR (blockocc_show_result, FALSE,
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"Show intermediate results");
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/* The values given here should reflect the values of bln_x_height and
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* bln_baseline_offset. These are defined as part of the word class
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* definition */
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EXTERN INT_VAR (blockocc_desc_height, 0,
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"Descender height after normalisation");
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EXTERN INT_VAR (blockocc_asc_height, 255,
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"Ascender height after normalisation");
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EXTERN INT_VAR (blockocc_band_count, 4, "Number of bands used");
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EXTERN double_VAR (textord_underline_threshold, 0.5,
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"Fraction of width occupied");
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/* ********************************************************************
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A note on transitions.
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We want to record occupancy in various bands. In general we need to consider
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7 situations:
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(1) (2) (3) (4)
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\ / \ / \ /
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__\_____/_____\_________/_____\_________/______ Upper Limit
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\ / \ / \ /
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/ \ \-->--/ \--<--/ /-----\
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v ^ / \(7)
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\ \ \ /
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\ \ /--<--\ /-->--\ \-----/
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____\______\____/_______\____/_______\_________ Lower Limit
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\ \ / \ / \
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(5) (6)
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We know that following "next" pointers around an outline keeps the black area
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on the LEFT. We only need be concerned with situations 1,2,3,5 and 7.
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4 and 6 can be ignored as they represent small incursions into a large black
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region which will be recorded elsewhere. Situations 3 and 5 define encloseed
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areas bounded by the upper and lower limits respectively. Situation 1 is open
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to the right, awaiting a closure by a situation 2 which is open to the right.
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Situation 7 is entirely enclosed within the band.
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The situations are refered to as region types and are determined by
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find_region_type.
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An empty region type is used to denote entry to an adjacent band and return
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to the original band at the same x location.
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***********************************************************************/
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#define REGION_TYPE_EMPTY 0
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#define REGION_TYPE_OPEN_RIGHT 1
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#define REGION_TYPE_OPEN_LEFT 2
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#define REGION_TYPE_UPPER_BOUND 3
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#define REGION_TYPE_UPPER_UNBOUND 4
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#define REGION_TYPE_LOWER_BOUND 5
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#define REGION_TYPE_LOWER_UNBOUND 6
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#define REGION_TYPE_ENCLOSED 7
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BAND bands[MAX_NUM_BANDS + 1]; // band defns
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/**********************************************************************
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* test_underline
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*
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* Check to see if the blob is an underline.
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* Return TRUE if it is.
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**********************************************************************/
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BOOL8 test_underline( //look for underlines
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BOOL8 testing_on, //drawing blob
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PBLOB *blob, //blob to test
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float baseline, //coords of baseline
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float xheight //height of line
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) {
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INT16 occ;
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INT16 blob_width; //width of blob
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BOX blob_box; //bounding box
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float occs[MAX_NUM_BANDS + 1]; //total occupancy
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blob_box = blob->bounding_box ();
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set_bands(baseline, xheight); //setup block occ
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blob_width = blob->bounding_box ().width ();
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if (testing_on) {
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// blob->plot(to_win,GOLDENROD,GOLDENROD);
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// line_color_index(to_win,GOLDENROD);
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// move2d(to_win,blob_box.left(),baseline);
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// draw2d(to_win,blob_box.right(),baseline);
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// move2d(to_win,blob_box.left(),baseline+xheight);
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// draw2d(to_win,blob_box.right(),baseline+xheight);
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tprintf
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("Testing underline on blob at (%d,%d)->(%d,%d), base=%g\nOccs:",
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blob->bounding_box ().left (), blob->bounding_box ().bottom (),
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blob->bounding_box ().right (), blob->bounding_box ().top (),
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baseline);
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}
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block_occ(blob, occs);
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if (testing_on) {
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for (occ = 0; occ <= MAX_NUM_BANDS; occ++)
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tprintf ("%g ", occs[occ]);
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tprintf ("\n");
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}
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if (occs[1] > occs[2] + occs[2] && occs[1] > occs[3] + occs[3]
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&& occs[1] > blob_width * textord_underline_threshold)
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return TRUE; //real underline
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if (occs[4] > occs[2] + occs[2]
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&& occs[4] > blob_width * textord_underline_threshold)
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return TRUE; //overline
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return FALSE; //neither
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}
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/**********************************************************************
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* test_underline
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*
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* Check to see if the blob is an underline.
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* Return TRUE if it is.
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**********************************************************************/
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BOOL8 test_underline( //look for underlines
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BOOL8 testing_on, //drawing blob
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C_BLOB *blob, //blob to test
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INT16 baseline, //coords of baseline
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INT16 xheight //height of line
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) {
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INT16 occ;
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INT16 blob_width; //width of blob
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BOX blob_box; //bounding box
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INT32 desc_occ;
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INT32 x_occ;
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INT32 asc_occ;
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STATS projection;
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blob_box = blob->bounding_box ();
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blob_width = blob->bounding_box ().width ();
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projection.set_range (blob_box.bottom (), blob_box.top () + 1);
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if (testing_on) {
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// blob->plot(to_win,GOLDENROD,GOLDENROD);
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// line_color_index(to_win,GOLDENROD);
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// move2d(to_win,blob_box.left(),baseline);
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// draw2d(to_win,blob_box.right(),baseline);
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// move2d(to_win,blob_box.left(),baseline+xheight);
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// draw2d(to_win,blob_box.right(),baseline+xheight);
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tprintf
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("Testing underline on blob at (%d,%d)->(%d,%d), base=%d\nOccs:",
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blob->bounding_box ().left (), blob->bounding_box ().bottom (),
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blob->bounding_box ().right (), blob->bounding_box ().top (),
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baseline);
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}
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horizontal_cblob_projection(blob, &projection);
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desc_occ = 0;
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for (occ = blob_box.bottom (); occ < baseline; occ++)
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if (occ <= blob_box.top () && projection.pile_count (occ) > desc_occ)
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//max in region
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desc_occ = projection.pile_count (occ);
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x_occ = 0;
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for (occ = baseline; occ <= baseline + xheight; occ++)
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if (occ >= blob_box.bottom () && occ <= blob_box.top ()
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&& projection.pile_count (occ) > x_occ)
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//max in region
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x_occ = projection.pile_count (occ);
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asc_occ = 0;
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for (occ = baseline + xheight + 1; occ <= blob_box.top (); occ++)
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if (occ >= blob_box.bottom () && projection.pile_count (occ) > asc_occ)
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asc_occ = projection.pile_count (occ);
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if (testing_on) {
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tprintf ("%d %d %d\n", desc_occ, x_occ, asc_occ);
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}
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if (desc_occ == 0 && x_occ == 0 && asc_occ == 0) {
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tprintf ("Bottom=%d, top=%d, base=%d, x=%d\n",
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blob_box.bottom (), blob_box.top (), baseline, xheight);
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projection.print (stdout, TRUE);
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}
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if (desc_occ > x_occ + x_occ
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&& desc_occ > blob_width * textord_underline_threshold)
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return TRUE; //real underline
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if (asc_occ > x_occ + x_occ
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&& asc_occ > blob_width * textord_underline_threshold)
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return TRUE; //overline
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return FALSE; //neither
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}
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/**********************************************************************
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* horizontal_cblob_projection
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*
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* Compute the horizontal projection of a cblob from its outlines
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* and add to the given STATS.
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**********************************************************************/
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void horizontal_cblob_projection( //project outlines
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C_BLOB *blob, //blob to project
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STATS *stats //output
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) {
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//outlines of blob
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C_OUTLINE_IT out_it = blob->out_list ();
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for (out_it.mark_cycle_pt (); !out_it.cycled_list (); out_it.forward ()) {
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horizontal_coutline_projection (out_it.data (), stats);
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}
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}
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/**********************************************************************
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* horizontal_coutline_projection
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*
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* Compute the horizontal projection of a outline from its outlines
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* and add to the given STATS.
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**********************************************************************/
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void horizontal_coutline_projection( //project outlines
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C_OUTLINE *outline, //outline to project
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STATS *stats //output
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) {
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ICOORD pos; //current point
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ICOORD step; //edge step
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INT32 length; //of outline
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INT16 stepindex; //current step
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C_OUTLINE_IT out_it = outline->child ();
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pos = outline->start_pos ();
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length = outline->pathlength ();
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for (stepindex = 0; stepindex < length; stepindex++) {
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step = outline->step (stepindex);
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if (step.y () > 0) {
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stats->add (pos.y (), pos.x ());
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}
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else if (step.y () < 0) {
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stats->add (pos.y () - 1, -pos.x ());
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}
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pos += step;
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}
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for (out_it.mark_cycle_pt (); !out_it.cycled_list (); out_it.forward ()) {
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horizontal_coutline_projection (out_it.data (), stats);
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}
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}
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void set_bands( //init from varibles
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float baseline, //top of bottom band
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float xheight //height of split band
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) {
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INT16 int_bl, int_xh; //for band.set
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bands[DOT_BAND].set (0, 0, 0, 0, 0, 0);
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int_bl = (INT16) baseline;
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int_xh = (INT16) xheight;
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bands[1].set (int_bl, int_bl, int_bl,
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NO_LOWER_LIMIT, NO_LOWER_LIMIT, NO_LOWER_LIMIT);
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bands[2].set (int_bl + int_xh / 2, int_bl + int_xh / 2, int_bl + int_xh / 2,
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int_bl, int_bl, int_bl);
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bands[3].set (int_bl + int_xh, int_bl + int_xh, int_bl + int_xh,
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int_bl + int_xh / 2, int_bl + int_xh / 2,
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int_bl + int_xh / 2);
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bands[4].set (NO_UPPER_LIMIT, NO_UPPER_LIMIT, NO_UPPER_LIMIT,
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int_bl + int_xh, int_bl + int_xh, int_bl + int_xh);
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}
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void
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block_occ (PBLOB * blob, //blob to do
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float occs[] //output histogram
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) {
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int band_index; //current band
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REGION_OCC *region; //current segment
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REGION_OCC_LIST region_occ_list[MAX_NUM_BANDS + 1];
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REGION_OCC_IT region_it; //region iterator
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find_transitions(blob, region_occ_list);
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compress_region_list(region_occ_list);
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for (band_index = 0; band_index <= MAX_NUM_BANDS; band_index++) {
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occs[band_index] = 0.0f;
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region_it.set_to_list (®ion_occ_list[band_index]);
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for (region_it.mark_cycle_pt (); !region_it.cycled_list ();
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region_it.forward ()) {
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region = region_it.data ();
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occs[band_index] += region->max_x - region->min_x;
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}
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}
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}
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void find_transitions(PBLOB *blob, //blob to do
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REGION_OCC_LIST *region_occ_list) {
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OUTLINE_IT outline_it;
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BOX box;
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POLYPT_IT pt_it;
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FCOORD point1;
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FCOORD point2;
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FCOORD *entry_pt = &point1;
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FCOORD *exit_pt = &point2;
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FCOORD *temp_pt;
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INT16 increment;
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INT16 prev_band;
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INT16 band;
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INT16 next_band;
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float min_x;
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float max_x;
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float min_y;
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float max_y;
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BOOL8 doubly_contained;
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outline_it = blob->out_list ();
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for (outline_it.mark_cycle_pt (); !outline_it.cycled_list ();
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outline_it.forward ()) {
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find_fbox(&outline_it, &min_x, &min_y, &max_x, &max_y);
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if (bands[DOT_BAND].range_in_nominal (max_y, min_y)) {
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record_region(DOT_BAND,
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min_x,
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max_x,
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REGION_TYPE_ENCLOSED,
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region_occ_list);
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}
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else {
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band = find_containing_maximal_band (max_y, min_y,
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&doubly_contained);
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if (band != UNDEFINED_BAND) {
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//No transitions
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if (!doubly_contained)
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record_region(band,
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min_x,
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max_x,
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REGION_TYPE_ENCLOSED,
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region_occ_list);
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else {
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// if (wordocc_debug_on && blockocc_show_result)
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// {
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// fprintf( db_win,
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// "Ignoring doubly contained outline (%d, %d) (%d, %d)\n",
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// box.left(), box.top(),
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// box.right(), box.bottom());
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// fprintf( db_win, "\tContained in bands %d and %d\n",
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// band, band + 1 );
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// }
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}
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}
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else {
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//There are transitns
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/*
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Determining a good start point for recognising transitions between bands
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is complicated by error limits on bands. We need to find a line which
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significantly occupies a band.
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Having found such a point, we need to find a significant transition out of
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its band and start the walk around the outline from there.
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Note that we are relying on having recognised and dealt with elsewhere,
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outlines which do not significantly occupy more than one region. A
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particularly nasty case of this are outlines which do not significantly
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occupy ANY band. I.e. they lie entirely within the error limits.
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Given this condition, all remaining outlines must contain at least one
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significant line. */
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pt_it = outline_it.data ()->polypts ();
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find_significant_line(pt_it, &band);
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*entry_pt = pt_it.data ()->pos;
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next_region(&pt_it,
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band,
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&next_band,
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&min_x,
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&max_x,
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&increment,
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exit_pt);
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pt_it.mark_cycle_pt ();
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// Found the first real transition, so start walking the outline from here.
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do {
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prev_band = band;
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band = band + increment;
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while (band != next_band) {
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temp_pt = entry_pt;
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entry_pt = exit_pt;
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exit_pt = temp_pt;
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min_x = max_x = entry_pt->x ();
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find_trans_point (&pt_it, band, band + increment,
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exit_pt);
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maintain_limits (&min_x, &max_x, exit_pt->x ());
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record_region (band,
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min_x,
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max_x,
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find_region_type (prev_band,
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band,
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band + increment,
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entry_pt->x (),
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exit_pt->x ()),
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region_occ_list);
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prev_band = band;
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band = band + increment;
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}
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temp_pt = entry_pt;
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entry_pt = exit_pt;
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exit_pt = temp_pt;
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min_x = max_x = entry_pt->x ();
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next_region(&pt_it,
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band,
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&next_band,
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&min_x,
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&max_x,
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&increment,
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exit_pt);
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record_region (band,
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min_x,
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max_x,
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find_region_type (prev_band,
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band,
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band + increment,
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entry_pt->x (),
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exit_pt->x ()),
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region_occ_list);
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}
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while (!pt_it.cycled_list ());
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}
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}
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}
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}
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void record_region( //add region on list
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INT16 band,
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float new_min,
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float new_max,
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INT16 region_type,
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REGION_OCC_LIST *region_occ_list) {
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REGION_OCC_IT it (&(region_occ_list[band]));
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|
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// if (wordocc_debug_on && blockocc_show_result)
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// fprintf( db_win, "\nBand %d, region type %d, from %f to %f",
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// band, region_type, new_min, new_max );
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if ((region_type == REGION_TYPE_UPPER_UNBOUND) ||
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(region_type == REGION_TYPE_LOWER_UNBOUND) ||
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(region_type == REGION_TYPE_EMPTY))
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return;
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if (it.empty ()) {
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it.add_after_stay_put (new REGION_OCC (new_min, new_max, region_type));
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}
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else {
|
|
|
|
/* Insert in sorted order of average limit */
|
|
|
|
while ((new_min + new_max > it.data ()->min_x + it.data ()->max_x) &&
|
|
(!it.at_last ()))
|
|
it.forward ();
|
|
|
|
if ((it.at_last ()) && //at the end
|
|
(new_min + new_max > it.data ()->min_x + it.data ()->max_x))
|
|
//new range > current
|
|
it.add_after_stay_put (new REGION_OCC (new_min,
|
|
new_max, region_type));
|
|
else {
|
|
it.add_before_stay_put (new REGION_OCC (new_min,
|
|
new_max, region_type));
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
INT16 find_containing_maximal_band( //find range's band
|
|
float y1,
|
|
float y2,
|
|
BOOL8 *doubly_contained) {
|
|
INT16 band;
|
|
|
|
*doubly_contained = FALSE;
|
|
|
|
for (band = 1; band <= blockocc_band_count; band++) {
|
|
if (bands[band].range_in_maximal (y1, y2)) {
|
|
if ((band < blockocc_band_count) &&
|
|
(bands[band + 1].range_in_maximal (y1, y2)))
|
|
*doubly_contained = TRUE;
|
|
return band;
|
|
}
|
|
}
|
|
return UNDEFINED_BAND;
|
|
}
|
|
|
|
|
|
void find_significant_line(POLYPT_IT it, INT16 *band) {
|
|
|
|
/* Look for a line which significantly occupies at least one band. I.e. part
|
|
of the line is in the non-margin part of the band. */
|
|
|
|
*band = find_overlapping_minimal_band (it.data ()->pos.y (),
|
|
it.data ()->pos.y () +
|
|
it.data ()->vec.y ());
|
|
|
|
while (*band == UNDEFINED_BAND) {
|
|
it.forward ();
|
|
*band = find_overlapping_minimal_band (it.data ()->pos.y (),
|
|
it.data ()->pos.y () +
|
|
it.data ()->vec.y ());
|
|
}
|
|
}
|
|
|
|
|
|
INT16 find_overlapping_minimal_band( //find range's band
|
|
float y1,
|
|
float y2) {
|
|
INT16 band;
|
|
|
|
for (band = 1; band <= blockocc_band_count; band++) {
|
|
if (bands[band].range_overlaps_minimal (y1, y2))
|
|
return band;
|
|
}
|
|
return UNDEFINED_BAND;
|
|
}
|
|
|
|
|
|
INT16 find_region_type(INT16 entry_band,
|
|
INT16 current_band,
|
|
INT16 exit_band,
|
|
float entry_x,
|
|
float exit_x) {
|
|
if (entry_band > exit_band)
|
|
return REGION_TYPE_OPEN_RIGHT;
|
|
if (entry_band < exit_band)
|
|
return REGION_TYPE_OPEN_LEFT;
|
|
if (entry_x == exit_x)
|
|
return REGION_TYPE_EMPTY;
|
|
if (entry_band > current_band) {
|
|
if (entry_x < exit_x)
|
|
return REGION_TYPE_UPPER_BOUND;
|
|
else
|
|
return REGION_TYPE_UPPER_UNBOUND;
|
|
}
|
|
else {
|
|
if (entry_x > exit_x)
|
|
return REGION_TYPE_LOWER_BOUND;
|
|
else
|
|
return REGION_TYPE_LOWER_UNBOUND;
|
|
}
|
|
}
|
|
|
|
|
|
void find_trans_point(POLYPT_IT *pt_it,
|
|
INT16 current_band,
|
|
INT16 next_band,
|
|
FCOORD *transition_pt) {
|
|
float x1, x2, y1, y2; // points of edge
|
|
float gradient; // m in y = mx + c
|
|
float offset; // c in y = mx + c
|
|
|
|
if (current_band < next_band)
|
|
transition_pt->set_y (bands[current_band].max);
|
|
//going up
|
|
else
|
|
transition_pt->set_y (bands[current_band].min);
|
|
//going down
|
|
|
|
x1 = pt_it->data ()->pos.x ();
|
|
x2 = x1 + pt_it->data ()->vec.x ();
|
|
y1 = pt_it->data ()->pos.y ();
|
|
y2 = y1 + pt_it->data ()->vec.y ();
|
|
|
|
if (x1 == x2)
|
|
transition_pt->set_x (x1); //avoid div by 0
|
|
else {
|
|
if (y1 == y2) //avoid div by 0
|
|
transition_pt->set_x ((x1 + x2) / 2.0);
|
|
else {
|
|
gradient = (y1 - y2) / (float) (x1 - x2);
|
|
offset = y1 - x1 * gradient;
|
|
transition_pt->set_x ((transition_pt->y () - offset) / gradient);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void next_region(POLYPT_IT *start_pt_it,
|
|
INT16 start_band,
|
|
INT16 *to_band,
|
|
float *min_x,
|
|
float *max_x,
|
|
INT16 *increment,
|
|
FCOORD *exit_pt) {
|
|
/*
|
|
Given an edge and a band which the edge significantly occupies, find the
|
|
significant end of the region containing the band. I.e. find an edge which
|
|
points to another band such that the outline subsequetly moves significantly
|
|
out of the starting band.
|
|
|
|
Note that we can assume that we are significantly inside the current band to
|
|
start with because the edges passed will be from previous calls to this
|
|
routine apart from the first - the result of which is only used to establish
|
|
the start of the first region.
|
|
*/
|
|
|
|
INT16 band; //band of current edge
|
|
INT16 prev_band = start_band; //band of prev edge
|
|
//edge crossing out
|
|
POLYPT_IT last_transition_out_it;
|
|
//band it pts to
|
|
INT16 last_trans_out_to_band = 0;
|
|
float ext_min_x = 0.0f;
|
|
float ext_max_x = 0.0f;
|
|
|
|
start_pt_it->forward ();
|
|
band = find_band (start_pt_it->data ()->pos.y ());
|
|
|
|
while ((band == start_band) ||
|
|
bands[start_band].in_maximal (start_pt_it->data ()->pos.y ())) {
|
|
if (band == start_band) {
|
|
//Return to start band
|
|
if (prev_band != start_band) {
|
|
*min_x = ext_min_x;
|
|
*max_x = ext_max_x;
|
|
}
|
|
maintain_limits (min_x, max_x, start_pt_it->data ()->pos.x ());
|
|
}
|
|
else {
|
|
if (prev_band == start_band) {
|
|
//Exit from start band
|
|
//so remember edge
|
|
last_transition_out_it = *start_pt_it;
|
|
//before we left
|
|
last_transition_out_it.backward ();
|
|
//and band it pts to
|
|
last_trans_out_to_band = band;
|
|
ext_min_x = *min_x;
|
|
ext_max_x = *max_x;
|
|
}
|
|
maintain_limits (&ext_min_x, &ext_max_x,
|
|
start_pt_it->data ()->pos.x ());
|
|
}
|
|
prev_band = band;
|
|
start_pt_it->forward ();
|
|
band = find_band (start_pt_it->data ()->pos.y ());
|
|
}
|
|
|
|
if (prev_band == start_band) { //exit from start band
|
|
*to_band = band;
|
|
//so remember edge
|
|
last_transition_out_it = *start_pt_it;
|
|
//before we left
|
|
last_transition_out_it.backward ();
|
|
}
|
|
else {
|
|
*to_band = last_trans_out_to_band;
|
|
}
|
|
|
|
if (*to_band > start_band)
|
|
*increment = 1;
|
|
else
|
|
*increment = -1;
|
|
|
|
find_trans_point (&last_transition_out_it, start_band,
|
|
start_band + *increment, exit_pt);
|
|
maintain_limits (min_x, max_x, exit_pt->x ());
|
|
*start_pt_it = last_transition_out_it;
|
|
}
|
|
|
|
|
|
INT16 find_band( // find POINT's band
|
|
float y) {
|
|
INT16 band;
|
|
|
|
for (band = 1; band <= blockocc_band_count; band++) {
|
|
if (bands[band].in_nominal (y))
|
|
return band;
|
|
}
|
|
BLOCKOCC.error ("find_band", ABORT, "Cant find band for %d", y);
|
|
return 0;
|
|
}
|
|
|
|
|
|
void compress_region_list( // join open regions
|
|
REGION_OCC_LIST *region_occ_list) {
|
|
REGION_OCC_IT it (&(region_occ_list[0]));
|
|
REGION_OCC *open_right = NULL;
|
|
|
|
INT16 i = 0;
|
|
|
|
for (i = 0; i <= blockocc_band_count; i++) {
|
|
it.set_to_list (&(region_occ_list[i]));
|
|
if (!it.empty ()) {
|
|
/* First check for left right pairs. Merge them into the open right and delete
|
|
the open left. */
|
|
open_right = NULL;
|
|
for (it.mark_cycle_pt (); !it.cycled_list (); it.forward ()) {
|
|
switch (it.data ()->region_type) {
|
|
case REGION_TYPE_OPEN_RIGHT:
|
|
{
|
|
if (open_right != NULL)
|
|
BLOCKOCC.error ("compress_region_list", ABORT,
|
|
"unmatched right");
|
|
else
|
|
open_right = it.data ();
|
|
break;
|
|
}
|
|
case REGION_TYPE_OPEN_LEFT:
|
|
{
|
|
if (open_right == NULL)
|
|
BLOCKOCC.error ("compress_region_list", ABORT,
|
|
"unmatched left");
|
|
else {
|
|
open_right->max_x = it.data ()->max_x;
|
|
open_right = NULL;
|
|
delete it.extract ();
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
if (open_right != NULL)
|
|
BLOCKOCC.error ("compress_region_list", ABORT,
|
|
"unmatched right remaining");
|
|
|
|
/* Now cycle the list again, merging and deleting any redundant regions */
|
|
it.move_to_first ();
|
|
open_right = it.data ();
|
|
while (!it.at_last ()) {
|
|
it.forward ();
|
|
if (it.data ()->min_x <= open_right->max_x) {
|
|
// Overlaps
|
|
if (it.data ()->max_x > open_right->max_x)
|
|
open_right->max_x = it.data ()->max_x;
|
|
// Extend
|
|
delete it.extract ();
|
|
}
|
|
else
|
|
open_right = it.data ();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void find_fbox(OUTLINE_IT *out_it,
|
|
float *min_x,
|
|
float *min_y,
|
|
float *max_x,
|
|
float *max_y) {
|
|
POLYPT_IT pt_it = out_it->data ()->polypts ();
|
|
FCOORD pt;
|
|
*min_x = 9999.0f;
|
|
*min_y = 9999.0f;
|
|
*max_x = 0.0f;
|
|
*max_y = 0.0f;
|
|
|
|
for (pt_it.mark_cycle_pt (); !pt_it.cycled_list (); pt_it.forward ()) {
|
|
pt = pt_it.data ()->pos;
|
|
maintain_limits (min_x, max_x, pt.x ());
|
|
maintain_limits (min_y, max_y, pt.y ());
|
|
}
|
|
}
|
|
|
|
|
|
void maintain_limits(float *min_x, float *max_x, float x) {
|
|
if (x > *max_x)
|
|
*max_x = x;
|
|
if (x < *min_x)
|
|
*min_x = x;
|
|
}
|