/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- detect_lines1
- detect_lines2
- my_sqrt
- detect_rotation_angle
- detect_text_lines
- adjust_text_lines
- calc_average
- detect_pictures
/*
This is a Optical-Character-Recognition program
Copyright (C) 2000-2007 Joerg Schulenburg
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
check README for my email address
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h> // toupper, tolower
#include "pgm2asc.h"
#include "gocr.h"
// ----- detect lines ---------------
/* suggestion: Fourier transform and set line frequency where the
amplitude has a maximum (JS: slow and not smarty enough).
option: range for line numbers 1..1000 or similar
todo: look for thickest line, and divide if thickness=2*mean_thickness
Set these elements of the box structs:
m1 <-- top of upper case letters and (bdfhkl) (can differ)
m2 <-- top of letters (acegmnopqrsuvwxyz)
m3 <-- baseline
m4 <-- bottom of hanging letters (gqpy)
performance can be improved by working with a temporary
list of boxes of the special text line
- Jun23,00 more robustness of m3 (test liebfrau1)
- Feb01,02 more robustness of m4 (test s46_084.pgm)
- Dec03,12 fix problems with footnotes
ToDo:
- generate lists of boxes per line (faster access)
- use statistics
- for each box look at it neighbours and set box-m1..m4
- m[1..4].max .min if m4.min-m3.max<1 probability lower
*/
int detect_lines1(pix * p, int x0, int y0, int dx, int dy)
{
int i, jj, j2, y, yy, my, mi, mc, i1, i2, i3, i4,
m1, m2, m3, m4, ma1, ma2, ma3, ma4, m3pre, m4pre;
struct box *box2, *box3; /* box3 is for verbose / debugging */
struct tlines *lines = &JOB->res.lines;
/* ToDo: optional read line-data from external source??? */
if (lines->num == 0) { // initialize one dummy-line for pictures etc.
lines->m4[0] = 0;
lines->m3[0] = 0;
lines->m2[0] = 0;
lines->m1[0] = 0;
lines->x0[0] = p->x; /* expand to left end during detection */
lines->x1[0] = 0; /* expand to right end */
lines->pitch[0] = JOB->cfg.spc; /* default word pitch */
lines->mono[0] = 0; /* default spacing = prop */
lines->num++;
}
i = lines->num;
if (dy < 4)
return 0; /* image is to low for latin chars */
my = jj = 0;
// get the mean height of all hollow chars
// (better than mean value of everything including bg-pattern or dust?)
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if ( box2->c != PICTURE
&& box2->num_frames>1 && box2->num_frames<3 /* 1 or 2 holes */
&& box2->y0 >= y0 && box2->y1 <= y0 + dy
&& box2->x0 >= x0 && box2->x1 <= x0 + dx
&& box2->frame_vol[0]>0
&& box2->frame_vol[1]<0
) {
jj++;
my += box2->y1 - box2->y0 + 1;
}
} end_for_each(&(JOB->res.boxlist));
if (jj==0) {
// get the mean height of all chars
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if ( box2->c != PICTURE
&& box2->y1 - box2->y0 + 1 >= 4 /* 4x6 font */
&& box2->y0 >= y0 && box2->y1 <= y0 + dy
&& box2->x0 >= x0 && box2->x1 <= x0 + dx ) {
jj++;
my += box2->y1 - box2->y0 + 1;
}
} end_for_each(&(JOB->res.boxlist));
}
if (jj == 0)
return 0; /* no chars detected */
/* ToDo: a better way could be to mark good boxes (of typical high a-zA-Z0-9)
* first and handle only marked boxes for line scan, exclude ?!,.:;etc
* but without setect the chars itself (using good statistics)
* see adjust_text_lines()
*/
my /= jj; /* we only care about chars with high arround my */
if (JOB->cfg.verbose & 16)
fprintf(stderr,"\n# detect_lines1(%d %d %d %d) vvv&16 chars=%d my=%d\n# ",
x0, y0, dx, dy, jj, my);
// "my" is the average over the whole image (bad, if different fontsizes)
if (my < 4)
return 0; /* mean high is to small => error */
m4pre=m3pre=y0; /* lower bond of upper line */
// better function for scanning line around a letter ???
// or define lines around known chars "eaTmM"
for (j2 = y = y0; y < y0 + dy; y++) {
// look for max. of upper and lower bound of next line
m1 = y0 + dy;
jj = 0;
#if 1
/* this is only for test runs */
if (JOB->cfg.verbose & 16)
fprintf(stderr,"searching new line %d\n# ",i /* lines->num */);
#endif
box3 = NULL; /* mark the most upper box starting next line */
// find highest point of next line => store to m1-min (m1>=y)
// only objects greater 2/3*my and smaller 3*my are allowed
// a higher "!" at end of line can result in a to low m1
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line>0 || box2->c == PICTURE) continue;
if (lines->dx)
yy = lines->dy * box2->x0 / (lines->dx); /* correct crooked lines */
else yy=0;
if ( box2->y0 >= y + yy && box2->y1 < y0 + dy // lower than y
&& box2->x0 >= x0 && box2->x1 < x0 + dx // within box ?
&& box2->c != PICTURE // no picture
&& box2->num_boxes <= 1 // ignore 2 for "!?i" 3 for "ä"
&& 3 * (box2->y1 - box2->y0) > 2 * my // not to small
&& (box2->y1 - box2->y0) < 3 * my // not to big
&& (box2->y1 - box2->y0) > 4) // minimum absolute size
{
if (box2->y0 < m1 + yy) {
m1 = box2->y0 - yy; /* highest upper boundary */
box3 = box2;
}
// fprintf(stderr,"\n %3d %3d %+3d %d m1= %3d",
// box2->x0, box2->y0, box2->y1 - box2->y0 + 1, box2->num_boxes, m1);
}
} end_for_each(&(JOB->res.boxlist));
if (!box3 || m1 >= y0+dy) break; /* no further line found */
if (JOB->cfg.verbose & 16)
fprintf(stderr," most upper box at new line xy= %4d %4d %+4d %+4d\n# ",
box3->x0, box3->y0, box3->x1-box3->x0, box3->y1-box3->y0);
// at the moment values depend from single chars, which can
// result in bad values (ex: 4x6 /\=)
// ToDo: 2) mean size of next line (store list of y0,y1)
// ToDo: 3) count num0[(y0-m1)*16/my], num1[(y1-m1)*16/my]
// ToDo: or down-top search horizontal nerarest neighbours
lines->x0[i] = x0 + dx - 1; /* expand during operation to left end */
lines->x1[i] = x0; /* expand to the right end of line */
m4=m2=m1; mi=m1+my; m3=m1+2*my; jj=0;
// find limits for upper bound, base line and ground line
// m2-max m3-min m4-max
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line>0 || box2->c == PICTURE) continue;
if ( box2->y0 < y0 || box2->y1 >= y0 + dy
|| box2->x0 < x0 || box2->x1 >= x0 + dx ) continue; // out of image
if (lines->dx) yy = lines->dy * box2->x0 / (lines->dx);
else yy=0;
/* check for ij-dots, used if chars of same high */
if ( box2->y0 >= y + yy
&& box2->y0 >= y
&& (box2->y1 - box2->y0) < my
&& box2->y1 < m1 + yy + my/4
&& box2->y0 < mi + yy ) {
mi = box2->y0 - yy; /* highest upper boundary i-dot */
}
// fprintf(stderr,"\n check %3d %3d-%3d y=%d yy=%d m1=%d", box2->x0, box2->y0, box2->y1, y, yy, m1);
/* get m2-max m3-min m4-max */
if ( box2->y0 >= y + yy // lower than y
&& 3 * (box2->y1 - box2->y0 + 1) > 2 * my // right size ?
&& (box2->y1 - box2->y0 + 1) < 3 * my // font mix, size = 2.6*my
&& (box2->y1 - box2->y0 + 1) > 3 // 4x6 lowercase=4
&& box2->y0 >= m1 // in m1 range?
&& box2->y0 <= m1 + yy + 9 * my / 8 // my can be to small if mixed
// ToDo: we need a better (local?) algorithm for big headlines > 2*my
&& box2->y1 <= m1 + yy + 3 * my
&& box2->y1 >= m1 + yy + my / 2
// lines can differ in high, my may be to small (smaller headlines)
&& box2->y0+box2->y1 <= 2*box3->y1
)
{
jj++; // count chars for debugging purpose
if (box2->y0 > m2 + yy) {
m2 = box2->y0 - yy; /* highest upper boundary */
if (JOB->cfg.verbose & 16)
fprintf(stderr," set m2= %d yy= %d\n# ",m2, yy);
}
if (box2->y1 > m4 + yy && (my>6 || box2->y1 < m3+my)) {
m4 = box2->y1 - yy; /* lowest lower boundary, small font lines can touch */
}
if ( box2->y1 < m3 + yy
&& ( ( 2*box2->y1 > m2+ m4+yy && m2>m1)
|| ( 4*box2->y1 > m1+3*m4+yy) ) ) // care for TeX: \(^1\)Footnote 2003
/* "'!?" could cause trouble here, therefore this lines */
/* ToDo: get_bw costs time, check pre and next */
if( get_bw(box2->x0,box2->x1,box2->y1+1 ,box2->y1+my/2,box2->p,JOB->cfg.cs,1) == 0
|| get_bw(box2->x0,box2->x1,box2->y1+my/2,box2->y1+my/2,box2->p,JOB->cfg.cs,1) == 1
|| num_cross(box2->x0,box2->x1,(box2->y0+box2->y1)/2,(box2->y0+box2->y1)/2,box2->p,JOB->cfg.cs)>2 )
{
m3 = box2->y1 - yy; /* highest lower boundary */
// printf("\n# set1 m3 m=%3d %+2d %+2d %+2d",m1,m2-m1,m3-m1,m4-m1);
// out_x(box2);
}
if (box2->y0 + box2->y1 > 2*(m3 + yy)
&& box2->y1 < m4 + yy - my/4 -1
&& box2->y1 >= (m2 + m4)/2 // care for TeX: \(^1\)Footnote 2003
&& m2 > m1 ) // be sure to not use ', m2 must be ok
{
m3 = box2->y1 - yy; /* highest lower boundary */
// printf("\n# set2 m3 m=%3d %+2d %+2d %+2d",m1,m2-m1,m3-m1,m4-m1);
// out_x(box2);
}
if (box2->x1>lines->x1[i]) lines->x1[i] = box2->x1; /* right end */
if (box2->x0<lines->x0[i]) lines->x0[i] = box2->x0; /* left end */
// printf(" m=%3d %+2d %+2d %+2d yy=%3d\n",m1,m2-m1,m3-m1,m4-m1,yy);
}
} end_for_each(&(JOB->res.boxlist));
#if 1
/* this is only for test runs */
if (JOB->cfg.verbose & 16)
fprintf(stderr," step 1 y=%4d m= %4d %+3d %+3d %+3d"
" my=%2d chars=%3d\n# ",
y, m1, m2-m1, m3-m1, m4-m1, my, jj);
#endif
if (m3 == m1)
break;
#if 1 /* make averages about the line */
// same again better estimation
mc = (3 * m3 + m1) / 4; /* lower center ? */
ma1 = ma2 = ma3 = ma4 = i1 = i2 = i3 = i4 = jj = 0;
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line>0 || box2->c == PICTURE) continue;
if (lines->dx) yy = lines->dy * box2->x0 / (lines->dx); else yy=0;
if (box2->y0 >= y + yy && box2->y1 < y0 + dy // lower than y
&& box2->x0 >= x0 && box2->x1 < x0 + dx // in box ?
&& box2->c != PICTURE // no picture
&& 2 * (box2->y1 - box2->y0) > my // right size ?
&& (box2->y1 - box2->y0) < 4 * my) {
if ( box2->y0 - yy >= m1-my/4
&& box2->y0 - yy <= m2+my/4
&& box2->y1 - yy >= m3-my/4
&& box2->y1 - yy <= m4+my/4 ) { /* its within allowed range! */
// jj++; // not used
if (abs(box2->y0 - yy - m1) <= abs(box2->y0 - yy - m2))
{ i1++; ma1 += box2->y0 - yy; }
else { i2++; ma2 += box2->y0 - yy; }
if (abs(box2->y1 - yy - m3) < abs(box2->y1 - yy - m4))
{ i3++; ma3 += box2->y1 - yy; }
else { i4++; ma4 += box2->y1 - yy; }
if (box2->x1>lines->x1[i]) lines->x1[i] = box2->x1; /* right end */
if (box2->x0<lines->x0[i]) lines->x0[i] = box2->x0; /* left end */
}
}
} end_for_each(&(JOB->res.boxlist));
if (i1) m1 = (ma1+i1/2) / i1; /* best rounded */
if (i2) m2 = (ma2+i2/2) / i2;
if (i3) m3 = (ma3+i3-1) / i3; /* round up */
if (i4) m4 = (ma4+i4-1) / i4;
// printf("\n# .. set3 m3 m=%3d %+2d %+2d %+2d",m1,m2-m1,m3-m1,m4-m1);
#endif
/* expand right and left end of line */
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line>0 || box2->c == PICTURE) continue;
if (lines->dx) yy = lines->dy * box2->x0 / (lines->dx); else yy=0;
if ( box2->y0 >= y0 && box2->y1 < y0 + dy
&& box2->x0 >= x0 && box2->x1 < x0 + dx // in box ?
&& box2->c != PICTURE // no picture
&& box2->y0 >= m1-1
&& box2->y0 <= m4
&& box2->y1 >= m1
&& box2->y1 <= m4+1 ) { /* its within line */
if (box2->x1>lines->x1[i]) lines->x1[i] = box2->x1; /* right end */
if (box2->x0<lines->x0[i]) lines->x0[i] = box2->x0; /* left end */
}
} end_for_each(&(JOB->res.boxlist));
#if 1
/* this is only for test runs */
if (JOB->cfg.verbose & 16)
fprintf(stderr," step 2 y=%4d m= %4d %+3d %+3d %+3d\n# ",
y,m1,m2-m1,m3-m1,m4-m1);
#endif
if (m4 == m1) {
if(m3+m4>2*y) y = (m4+m3)/2; /* lower end may overlap the next line */
continue;
}
jj=0;
lines->wt[i] = 100;
if (5 * (m2 - m1 +1) < m3 - m2 || (m2 - m1) < 2) jj|=1; /* same high */
if (5 * (m4 - m3 +1) < m3 - m2 || (m4 - m3) < 1) jj|=2; /* same base */
if (jj&1) lines->wt[i] = 75*lines->wt[i]/100;
if (jj&2) lines->wt[i] = 75*lines->wt[i]/100;
if (jj>0 && JOB->cfg.verbose) {
fprintf(stderr," trouble on line %d, wt*100= %d\n",i,lines->wt[i]);
fprintf(stderr,"# m= %4d %+3d %+3d %+3d\n",m1,m2-m1,m3-m1,m4-m1);
fprintf(stderr,"# i= %3d %3d %3d %3d (counts)\n",i1,i2,i3,i4);
if (jj==3) fprintf(stderr,"# all boxes of same high!\n# ");
if (jj==1) fprintf(stderr,"# all boxes of same upper bound!\n# ");
if (jj==2) fprintf(stderr,"# all boxes of same lower bound!\n# ");
}
/* ToDo: check for dots ij,. to get the missing information */
#if 1
/* jj=3: ABCDEF123456 or mnmno or gqpy or lkhfdtb => we are in trouble */
if (jj==3 && (m4-m1)>my) { jj=0; m2=m1+my/8+1; m4=m3+my/8+1; } /* ABC123 */
/* using idots, may fail on "ABCDEFGÄÜÖ" */
if (jj==3 && mi>0 && mi<m1 && mi>m4pre) { jj=2; m1=mi; } /* use ij dots */
if (jj==1 && m2-(m3-m2)/4>m3pre ) { /* expect: acegmnopqrsuvwxyz */
if (m1-m4pre<m4-m1) /* fails for 0123ABCD+Q$ */
m1 = ( m2 + m4pre ) / 2 ;
else
m1 = ( m2 - (m3 - m2) / 4 );
}
if (jj==3)
m2 = m1 + (m3 - m1) / 4 + 1; /* expect: 0123456789ABCDEF */
if ( (m2 - m1) < 2)
m2 = m1 + 2; /* font hight < 8 pixel ? */
if (jj&2)
m4 = m3 + (m4 - m1) / 4 + 1; /* chars have same lower base */
if (jj>0 && JOB->cfg.verbose & 16) {
fprintf(stderr," m= %4d %+2d %+2d %+2d my= %4d\n# ",
m1, m2-m1, m3-m1, m4-m1, my);
}
#endif
{ // empty space between lines
lines->m4[i] = m4;
lines->m3[i] = m3;
lines->m2[i] = m2;
lines->m1[i] = m1;
lines->pitch[i] = JOB->cfg.spc; /* default word pitch */
lines->pitch[i] = 0; /* default spacing */
if (JOB->cfg.verbose & 16)
fprintf(stderr, " m= %4d %+3d %+3d %+3d w= %d (line=%d)\n# ",
m1, m2 - m1, m3 - m1, m4 - m1, lines->wt[i], i);
if (i < MAXlines && m4 - m1 > 4)
i++;
if (i >= MAXlines) {
fprintf(stderr, "Warning: lines>MAXlines\n");
break;
}
}
if (m3+m4>2*y) y = (m3+m4)/2; /* lower end may overlap the next line */
if (m3>m3pre) m3pre = m3; else m3=y0; /* set for next-line scan */
if (m4>m4pre) m4pre = m4; else m4=y0; /* set for next-line scan */
}
lines->num = i;
if (JOB->cfg.verbose)
fprintf(stderr, " num_lines= %d", lines->num-1);
return 0;
}
// ----- layout analyzis of dx*dy region at x0,y0 -----
// ----- detect lines via recursive division (new version) ---------------
// what about text in frames???
// ToDo: change to bottom-top analyse or/and take rotation into account
int detect_lines2(pix *p,int x0,int y0,int dx,int dy,int r){
int i,x2,y2,x3,y3,x4,y4,x5,y5,y6,mx,my,x30,x31,y30,y31;
struct box *box2,*box3;
// shrink box
if(dx<=0 || dy<=0) return 0;
if(y0+dy< p->y/128 && y0==0) return 0; /* looks like dust */
if(y0>p->y-p->y/128 && y0+dy==p->y) return 0; /* looks like dust */
if(r>1000){ return -1;} // something is wrong
if(JOB->cfg.verbose)fprintf(stderr,"\n# r=%2d ",r);
mx=my=i=0; // mean thickness
// remove border, shrink size
x2=x0+dx-1; // min x
y2=y0+dy-1; // min y
x3=x0; // max x
y3=y0; // max y
for_each_data(&(JOB->res.boxlist)) {
box3 = (struct box *)list_get_current(&(JOB->res.boxlist));
if(box3->y0>=y0 && box3->y1<y0+dy &&
box3->x0>=x0 && box3->x1<x0+dx)
{
if( box3->x1 > x3 ) x3=box3->x1; // max x
if( box3->x0 < x2 ) x2=box3->x0; // min x
if( box3->y1 > y3 ) y3=box3->y1; // max y
if( box3->y0 < y2 ) y2=box3->y0; // min y
if(box3->c!=PICTURE)
if( box3->y1 - box3->y0 > 4 )
{
i++;
mx+=box3->x1-box3->x0+1; // mean x
my+=box3->y1-box3->y0+1; // mean y
}
}
} end_for_each(&(JOB->res.boxlist));
x0=x2; dx=x3-x2+1;
y0=y2; dy=y3-y2+1;
if(i==0 || dx<=0 || dy<=0) return 0;
mx/=i;my/=i;
// better look for widest h/v-gap, ToDo: vertical lines?
if(r<8){ // max. depth
// detect widest horizontal gap
y2=y3=y4=y5=y6=0;
x2=x3=x4=x5=y5=0;// min. 3 lines
// position and thickness of gap, y6=num_gaps, nbox^2 ops
for_each_data(&(JOB->res.boxlist)) { // not very efficient, sorry
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if( box2->c!=PICTURE ) /* ToDo: not sure, that this is a good idea */
if( box2->y0>=y0 && box2->y1<y0+dy
&& box2->x0>=x0 && box2->x1<x0+dx
&& box2->y1-box2->y0>my/2 ){ // no pictures & dust???
y4=y0+dy-1; // nearest vert. box
x4=x0+dx-1;
// ToDo: rotate back box2->x1,y1 to x21,y21
// look for nearest lowest (y4) and right (x4) neighbour
// of every box (box2)
for_each_data(&(JOB->res.boxlist)) {
box3 = (struct box *)list_get_current(&(JOB->res.boxlist));
if(box3!=box2)
if(box3->y0>=y0 && box3->y1<y0+dy)
if(box3->x0>=x0 && box3->x1<x0+dx)
if(box3->c!=PICTURE) /* ToDo: not sure, that this is a good idea */
if(box3->y1-box3->y0>my/2 ){
// ToDo: here we need the rotation around box2
x30=box3->x0;
x31=box3->x1;
y30=box3->y0;
y31=box3->y1;
// get min. distances to lower and to right direction
if( y31 > box2->y1 && y30 < y4 ) y4=y30-1;
if( x31 > box2->x1 && x30 < x4 ) x4=x30-1;
}
} end_for_each(&(JOB->res.boxlist));
// set the witdht and position of largest hor./vert. gap
// largest gap: width position
if( y4-box2->y1 > y3 ) { y3=y4-box2->y1; y2=(y4+box2->y1)/2; }
if( x4-box2->x1 > x3 ) { x3=x4-box2->x1; x2=(x4+box2->x1)/2; }
}
} end_for_each(&(JOB->res.boxlist));
// fprintf(stderr,"\n widest y-gap= %4d %4d",y2,y3);
// fprintf(stderr,"\n widest x-gap= %4d %4d",x2,x3);
i=0; // i=1 at x, i=2 at y
// this is the critical point
// is this a good decision or not???
if(x3>0 || y3>0){
if(x3>mx && x3>2*y3 && (dy>5*x3 || (x3>10*y3 && y3>0))) i=1; else
if(dx>5*y3 && y3>my) i=2;
}
// compare with largest box???
for_each_data(&(JOB->res.boxlist)) { // not very efficient, sorry
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if( box2->c == PICTURE )
if( box2->y0>=y0 && box2->y1<y0+dy
&& box2->x0>=x0 && box2->x1<x0+dx )
{ // hline ???
// largest gap: width position
if( box2->x1-box2->x0+4 > dx && box2->y1+4<y0+dy ) { y3=1; y2=box2->y1+1; i=2; break; }
if( box2->x1-box2->x0+4 > dx && box2->y0-4>y0 ) { y3=1; y2=box2->y0-1; i=2; break; }
if( box2->y1-box2->y0+4 > dy && box2->x1+4<x0+dx ) { x3=1; x2=box2->x1+1; i=1; break; }
if( box2->y1-box2->y0+4 > dy && box2->x0-4>x0 ) { x3=1; x2=box2->x0-1; i=1; break; }
}
} end_for_each(&(JOB->res.boxlist));
if(JOB->cfg.verbose)fprintf(stderr," i=%d",i);
if(JOB->cfg.verbose && i) fprintf(stderr," divide at %s x=%4d y=%4d dx=%4d dy=%4d",
((i)?( (i==1)?"x":"y" ):"?"),x2,y2,x3,y3);
// divide horizontally if v-gap is thicker than h-gap
// and length is larger 5*width
if(i==1){ detect_lines2(p,x0,y0,x2-x0+1,dy,r+1);
return detect_lines2(p,x2,y0,x0+dx-x2+1,dy,r+1); }
// divide vertically
if(i==2){ detect_lines2(p,x0,y0,dx,y2-y0+1,r+1);
return detect_lines2(p,x0,y2,dx,y0+dy-y2+1,r+1);
}
}
if(JOB->cfg.verbose) if(dx<5 || dy<7)fprintf(stderr," empty box");
if(dx<5 || dy<7) return 0; // do not care about dust
if(JOB->cfg.verbose)fprintf(stderr, " box detected at %4d %4d %4d %4d",x0,y0,dx,dy);
if(JOB->tmp.ppo.p){
for(i=0;i<dx;i++)put(&JOB->tmp.ppo,x0+i ,y0 ,255,16);
for(i=0;i<dx;i++)put(&JOB->tmp.ppo,x0+i ,y0+dy-1,255,16);
for(i=0;i<dy;i++)put(&JOB->tmp.ppo,x0 ,y0+i ,255,16);
for(i=0;i<dy;i++)put(&JOB->tmp.ppo,x0+dx-1,y0+i ,255,16);
// writebmp("out10.bmp",p2,JOB->cfg.verbose); // colored should be better
}
return detect_lines1(p,x0-0*1,y0-0*2,dx+0*2,dy+0*3);
/*
struct tlines *lines = &JOB->res.lines;
i=lines->num; lines->num++;
lines->m1[i]=y0; lines->m2[i]=y0+5*dy/16;
lines->m3[i]=y0+12*dy/16; lines->m4[i]=y0+dy-1;
lines->x0[i]=x0; lines->x1[i]=x0+dx-1;
if(JOB->cfg.verbose)fprintf(stderr," - line= %d",lines->num);
return 0;
*/
}
/* ToDo: herons algorithm for square root x=(x+y/x)/2 is more efficient
* than interval subdivision (?) (germ.: Intervallschachtelung)
* without using matlib
* see http://www.math.vt.edu/people/brown/doc/sqrts.pdf
*/
int my_sqrt(int x){
int y0=0,y1=x,ym;
for (;y0<y1-1;){
ym=(y0+y1)/2;
if (ym*ym<x) y0=ym; else y1=ym;
}
return y0;
}
/*
** Detect rotation angle (one for whole image)
** old: longest text-line and determining the angle of this line.
*
* search right nearest neighbour of each box and average vectors
* to get the text orientation,
* upside down decision is not made here (I dont know how to do it)
* ToDo: set job->res.lines.{dx,dy}
* pass 1: get mean vector to nearest char
* pass 2: get mean vector to nearest char without outriders to pass 1
* extimate direction as (dx,dy,num)[pass]
* ToDo: estimate an error, boxes only work fine for zero-rotation
* for 45 degree use vectors, not boxes to get base line
*/
#define INorm 1024 /* integer unit 1.0 */
int detect_rotation_angle(job_t *job){
struct box *box2, *box3,
*box_nn; /* nearest neighbour box */
int x2, y2, x3, y3, dist, mindist, pass,
rx=0, ry=0, re=0, // final result
/* to avoid 2nd run, wie store pairs in 2 different categories */
nn[4]={0,0,0,0}, /* num_pairs used for estimation [(pass-1)%2,pass%2] */
dx[4]={0,0,0,0}, /* x-component of rotation vector per pass */
dy[4]={0,0,0,0}, /* y-component of rotation vector per pass */
er[4]={INorm/4,0,0,0}; /* mean angle deviation to pass-1 (radius^2) */
// de; /* ToDo: absolute maximum error (dx^2+dy^2) */
// ToDo: next pass: go to bigger distances and reduce max error
// error is diff between passes? or diff of bottoms and top borders (?)
rx=1024; ry=0; // default
for (pass=0;pass<4;pass++) {
for_each_data(&(job->res.boxlist)) {
box2 = (struct box *)list_get_current(&(job->res.boxlist));
if (box2->c==PICTURE) continue;
/* subfunction probability of char */
// i?
// if (box2->x1 - box2->x0 < 3) continue; /* smallest font is 4x6 */
if (box2->y1 - box2->y0 < 4) continue;
/* set maximum possible distance */
box_nn=box2; // initial box to compare with
// ToDo: clustering or majority
// the algorithm is far from being perfect, pitfalls are likely
// but its better than the old algorithm, ToDo: database-rotated-images
mindist = job->src.p.x * job->src.p.x + job->src.p.y * job->src.p.y;
/* get middle point of the box */
x2 = (box2->x0 + box2->x1)/2;
y2 = (box2->y0 + box2->y1)/2;
re=0;
/* search for nearest neighbour box_nn[pass+1] of box_nn[pass] */
for_each_data(&(job->res.boxlist)) {
box3 = (struct box *)list_get_current(&(job->res.boxlist));
/* try to select only potential neighbouring chars */
/* select out all senseless combinations */
if (box3->c==PICTURE || box3==box2) continue;
x3 = (box3->x0 + box3->x1)/2;
y3 = (box3->y0 + box3->y1)/2; /* get middle point of the box */
if (x3<x2) continue; /* simplify by going right only */
// through-away deviation of angles if > pass-1?
// scalprod max in direction, cross prod min in direction
// a,b (vectors): <a,b>^2/(|a|*|b|)^2 = 0(90deg)..0.5(45deg).. 1(0deg)
// * 1024 ??
if (pass>0) { // new variant = scalar product
// danger of int overflow, ToDo: use int fraction
re =(int) ((1.*(x3-x2)*dx[pass-1]+(y3-y2)*dy[pass-1])
*(1.*(x3-x2)*dx[pass-1]+(y3-y2)*dy[pass-1])*INorm
/(1.*((x3-x2)*(x3-x2)+(y3-y2)*(y3-y2))
*(1.*dx[pass-1]*dx[pass-1]+dy[pass-1]*dy[pass-1])));
if (INorm-re>er[pass-1]) continue; // hits mean deviation
}
/* neighbours should have same order of size (?) */
if (3*(box3->y1-box3->y0+4) < 2*(box2->y1-box2->y0+1)) continue;
if (2*(box3->y1-box3->y0+1) > 3*(box2->y1-box2->y0+4)) continue;
if (2*(box3->x1-box3->x0+1) > 5*(box2->x1-box2->x0+4)) continue;
if (5*(box3->x1-box3->x0+4) < 2*(box2->x1-box2->x0+1)) continue;
/* should be in right range, Idea: center3 outside box2? noholes */
if ((x3<box2->x1-1) && (x3>box2->x0+1)
&& (y3<box2->y1-1) && (y3>box2->y0+1)) continue;
// if chars are of different size, connect careful
if ( abs(x3-x2) > 2*(box2->x1 - box2->x0 + box3->x1 - box3 ->x0 + 2)) continue;
if ( abs(y3-y2) > (box2->x1 - box2->x0 + box3->x1 - box3 ->x0 + 2)) continue;
dist = (y3-y2)*(y3-y2) + (x3-x2)*(x3-x2);
// make distances in pass-1 directions shorter or continue if not in pass-1 range?
if (dist<9) continue; /* minimum distance^2 is 3^2 */
if (dist<mindist) { mindist=dist; box_nn=box3;}
// fprintf(stderr,"x y %d %d %d %d dist %d min %d\n",
// x2,y2,x3,y3,dist,mindist);
} end_for_each(&(job->res.boxlist));
if (box_nn==box2) continue; /* has no neighbour, next box */
box3=box_nn; dist=mindist;
x3 = (box3->x0 + box3->x1)/2;
y3 = (box3->y0 + box3->y1)/2; /* get middle point of the box */
// dist = my_sqrt(1024*((x3-x2)*(x3-x2)+(y3-y2)*(y3-y2)));
// compare with first box
x2 = (box2->x0 + box2->x1)/2;
y2 = (box2->y0 + box2->y1)/2;
// if the high of neighbouring boxes differ, use min diff (y0,y1)
if (pass>0 && 16*abs(dy[pass-1]) < dx[pass-1]) // dont work for strong rot.
if (abs(box2->y1-box2->y0-box3->y1+box3->y0)>(box2->y1-box2->y0)/8) {
// ad eh ck ...
if (abs(box2->y1-box3->y1)<abs(y3-y2)) { y2=box2->y1; y3=box3->y1; }
// ag ep qu ...
if (abs(box2->y0-box3->y0)<abs(y3-y2)) { y2=box2->y0; y3=box3->y0; }
}
if (abs(x3-x2)<4) continue;
dx[pass]+=(x3-x2)*1024; /* normalized before averaging */
dy[pass]+=(y3-y2)*1024; /* 1024 is for the precision */
nn[pass]++;
if (pass>0) { // set error = mean deviation from pass -1
re = INorm-(int)((1.*(x3-x2)*dx[pass-1]+(y3-y2)*dy[pass-1])
*(1.*(x3-x2)*dx[pass-1]+(y3-y2)*dy[pass-1])*INorm
/((1.*(x3-x2)*(x3-x2)+(y3-y2)*(y3-y2))
*(1.*dx[pass-1]*dx[pass-1]+dy[pass-1]*dy[pass-1]))
);
er[pass]+=re;
}
#if 0
if(JOB->cfg.verbose)
fprintf(stderr,"# next nb (x,y,dx,dy,re) %6d %6d %5d %5d %5d pass %d\n",
x2, y2, x3-x2, y3-y2, re, pass+1);
#endif
} end_for_each(&(job->res.boxlist));
if (!nn[pass]) break;
if (nn[pass]) {
/* meanvalues */
rx=dx[pass]/=nn[pass];
ry=dy[pass]/=nn[pass];
if (pass>0) er[pass]/=nn[pass];
}
if(JOB->cfg.verbose)
fprintf(stderr,"# rotation angle (x,y,maxr,num)"
" %6d %6d %6d %4d pass %d\n",
rx, ry, er[pass], nn[pass], pass+1);
}
if (abs(ry*100)>abs(rx*50))
fprintf(stderr,"<!-- gocr will fail, strong rotation angle detected -->\n");
/* ToDo: normalize to 2^10 bit (square fits to 32 it) */
JOB->res.lines.dx=rx;
JOB->res.lines.dy=ry;
return 0;
}
/* ----- detect lines --------------- */
int detect_text_lines(pix * pp, int mo) {
if (JOB->cfg.verbose)
fprintf(stderr, "# detect.c detect_text_lines (vvv=16 for more info) ");
if (mo & 4){
if (JOB->cfg.verbose) fprintf(stderr, "# zoning\n# ... ");
detect_lines2(pp, 0, 0, pp->x, pp->y, 0); // later replaced by better algo
} else
detect_lines1(pp, 0, 0, pp->x, pp->y); // old algo
if(JOB->cfg.verbose) fprintf(stderr,"\n");
return 0;
}
/* ----- adjust lines --------------- */
// rotation angle? JOB->res.lines.dy, .x0 removed later
// this is for cases, where m1..m4 is not very sure detected before
// chars are recognized
int adjust_text_lines(pix * pp, int mo) {
struct box *box2;
int *m, /* summ m1..m4, num_chars for m1..m4, min m1..m4, max. m1..m4 */
l, i, dy, dx, diff=0, y0, y1;
if ((l=JOB->res.lines.num)<2) return 0; // ???
if (JOB->cfg.verbose)
fprintf(stderr, "# adjust text lines ");
m=(int *)malloc(l*16*sizeof(int));
if (!m) { fprintf(stderr," malloc failed\n"); return 0;}
for (i=0;i<16*l;i++) m[i]=0; /* initialize */
dy=JOB->res.lines.dy; /* tan(alpha) of skewing */
dx=JOB->res.lines.dx; /* old: width of image */
// js: later skewing is replaced by one transformation of vectorized image
if (dx)
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line<=0) continue;
if (box2->num_ac<1) continue;
if (box2->wac[0]<95) continue;
if (box2->m2==0 || box2->y1<box2->m2) continue; // char outside line
if (box2->m3==4 || box2->y0>box2->m3) continue; // char outside line
y0=box2->y0-((box2->x1)*dy/dx); /* corrected by page skewing */
y1=box2->y1-((box2->x1)*dy/dx);
if (strchr("aemnr",(char)box2->tac[0])) { // cC vV sS oO ... is unsure!
m[box2->line*16+1]+=y0; m[box2->line*16+5]++; // num m2
m[box2->line*16+2]+=y1; m[box2->line*16+6]++; // num m3
if (m[box2->line*16+ 9]>y0) m[box2->line*16+ 9]=y0; /* min m2 */
if (m[box2->line*16+13]<y0) m[box2->line*16+13]=y0; /* max m2 */
if (m[box2->line*16+10]>y1) m[box2->line*16+10]=y1; /* min m3 */
if (m[box2->line*16+14]<y1) m[box2->line*16+14]=y1; /* max m3 */
}
if (strchr("bdhklABDEFGHIKLMNRT123456789",(char)box2->tac[0])) {
m[box2->line*16+0]+=y0; m[box2->line*16+4]++; // num m1
m[box2->line*16+2]+=y1; m[box2->line*16+6]++; // num m3
if (m[box2->line*16+ 8]>y0) m[box2->line*16+ 8]=y0; /* min m1 */
if (m[box2->line*16+12]<y0) m[box2->line*16+12]=y0; /* max m1 */
if (m[box2->line*16+10]>y1) m[box2->line*16+10]=y1; /* min m3 */
if (m[box2->line*16+14]<y1) m[box2->line*16+14]=y1; /* max m3 */
}
if (strchr("gq",(char)box2->tac[0])) {
m[box2->line*16+1]+=y0; m[box2->line*16+5]++; // num m2
m[box2->line*16+3]+=y1; m[box2->line*16+7]++; // num m4
if (m[box2->line*16+ 9]>y0) m[box2->line*16+ 9]=y0; /* min m2 */
if (m[box2->line*16+13]<y0) m[box2->line*16+13]=y0; /* max m2 */
if (m[box2->line*16+11]>y1) m[box2->line*16+11]=y1; /* min m4 */
if (m[box2->line*16+15]<y1) m[box2->line*16+15]=y1; /* max m4 */
}
} end_for_each(&(JOB->res.boxlist));
for (i=1;i<l;i++) {
diff=0; // show diff per line
if (m[i*16+4]) diff+=abs(JOB->res.lines.m1[i]-m[i*16+0]/m[i*16+4]);
if (m[i*16+5]) diff+=abs(JOB->res.lines.m2[i]-m[i*16+1]/m[i*16+5]);
if (m[i*16+6]) diff+=abs(JOB->res.lines.m3[i]-m[i*16+2]/m[i*16+6]);
if (m[i*16+7]) diff+=abs(JOB->res.lines.m4[i]-m[i*16+3]/m[i*16+7]);
/* recalculate sureness, empirically */
if (m[i*16+4]*m[i*16+5]*m[i*16+6]*m[i*16+7] > 0)
JOB->res.lines.wt[i]=(JOB->res.lines.wt[i]+100)/2;
else
JOB->res.lines.wt[i]=(JOB->res.lines.wt[i]*90)/100;
// set mean values of sure detected bounds (rounded precisely)
if ( m[i*16+4]) JOB->res.lines.m1[i]=(m[i*16+0]+m[i*16+4]/2)/m[i*16+4];
if ( m[i*16+5]) JOB->res.lines.m2[i]=(m[i*16+1]+m[i*16+5]/2)/m[i*16+5];
if ( m[i*16+6]) JOB->res.lines.m3[i]=(m[i*16+2]+m[i*16+6]/2)/m[i*16+6];
if ( m[i*16+7]) JOB->res.lines.m4[i]=(m[i*16+3]+m[i*16+7]/2)/m[i*16+7];
// care about very small fonts
if (JOB->res.lines.m2[i]-JOB->res.lines.m1[i]<=1 && m[i*16+5]==0 && m[i*16+4])
JOB->res.lines.m2[i]=JOB->res.lines.m1[i]+2;
if (JOB->res.lines.m2[i]-JOB->res.lines.m1[i]<=1 && m[i*16+4]==0 && m[i*16+5])
JOB->res.lines.m1[i]=JOB->res.lines.m2[i]-2;
if (JOB->res.lines.m4[i]-JOB->res.lines.m3[i]<=1 && m[i*16+7]==0 && m[i*16+6])
JOB->res.lines.m4[i]=JOB->res.lines.m3[i]+2;
if (JOB->res.lines.m4[i]-JOB->res.lines.m3[i]<=1 && m[i*16+6]==0 && m[i*16+7])
JOB->res.lines.m3[i]=JOB->res.lines.m4[i]-2;
if ( m[i*16+7]<1 &&
JOB->res.lines.m4[i]
<=JOB->res.lines.m3[i]+(JOB->res.lines.m3[i]-JOB->res.lines.m2[i])/4 )
JOB->res.lines.m4[i]=
JOB->res.lines.m3[i]+(JOB->res.lines.m3[i]-JOB->res.lines.m2[i])/4;
if ( m[i*16+7]<1 && m[i*16+12+2]>0 && // m4 < max.m3+..
JOB->res.lines.m4[i] < 2*m[i*16+12+2]-JOB->res.lines.m3[i]+2 )
JOB->res.lines.m4[i] = 2*m[i*16+12+2]-JOB->res.lines.m3[i]+2;
if (JOB->res.lines.m4[i]<=JOB->res.lines.m3[i])
JOB->res.lines.m4[i]= JOB->res.lines.m3[i]+1; /* 4x6 */
if (JOB->cfg.verbose & 17)
fprintf(stderr, "\n# line= %3d m= %4d %+3d %+3d %+3d "
" n= %2d %2d %2d %2d w= %3d diff= %d",
i, JOB->res.lines.m1[i],
JOB->res.lines.m2[i] - JOB->res.lines.m1[i],
JOB->res.lines.m3[i] - JOB->res.lines.m1[i],
JOB->res.lines.m4[i] - JOB->res.lines.m1[i],
m[i*16+4],m[i*16+5],m[i*16+6],m[i*16+7],
JOB->res.lines.wt[i], diff);
}
diff=0; // count adjusted chars
#if 1
if (dx)
for_each_data(&(JOB->res.boxlist)) {
box2 = (struct box *)list_get_current(&(JOB->res.boxlist));
if (box2->line<=0) continue;
/* check if box was on the wrong line, ToDo: search a better line */
if (2*box2->y0<2*JOB->res.lines.m1[box2->line]
-JOB->res.lines.m4[box2->line]
+JOB->res.lines.m1[box2->line]) box2->line=0;
if (2*box2->y1>2*JOB->res.lines.m4[box2->line]
+JOB->res.lines.m4[box2->line]
-JOB->res.lines.m1[box2->line]) box2->line=0;
/* do adjustments */
if (box2->num_ac>0
&& box2->num_ac > 31 && box2->tac[0] < 127 /* islower(>256) may SIGSEGV */
&& strchr("cCoOpPsSuUvVwWxXyYzZ",(char)box2->tac[0])) { // no_wchar
if (box2->y0-((box2->x1)*dy/dx)
< (JOB->res.lines.m1[box2->line]+JOB->res.lines.m2[box2->line])/2
&& islower(box2->tac[0])
) { setac(box2,toupper((char)box2->tac[0]),(box2->wac[0]+101)/2); diff++; }
if (box2->y0-((box2->x1)*dy/dx)
> (JOB->res.lines.m1[box2->line]+JOB->res.lines.m2[box2->line]+1)/2
&& isupper(box2->tac[0])
){ setac(box2,tolower((char)box2->tac[0]),(box2->wac[0]+101)/2); diff++; }
}
box2->m1=JOB->res.lines.m1[box2->line]+((box2->x1)*dy/dx);
box2->m2=JOB->res.lines.m2[box2->line]+((box2->x1)*dy/dx);
box2->m3=JOB->res.lines.m3[box2->line]+((box2->x1)*dy/dx);
box2->m4=JOB->res.lines.m4[box2->line]+((box2->x1)*dy/dx);
} end_for_each(&(JOB->res.boxlist));
#endif
free(m);
if(JOB->cfg.verbose) fprintf(stderr,"\n# changed_chars= %d\n",diff);
return(diff);
}
/* ---- measure mean character
* recalculate mean width and high after changes in boxlist
* ToDo: only within a Range?
*/
int calc_average() {
int i = 0, x0, y0, x1, y1;
struct box *box4;
JOB->res.numC = 0;
JOB->res.sumY = 0;
JOB->res.sumX = 0;
for_each_data(&(JOB->res.boxlist)) {
box4 = (struct box *)list_get_current(&(JOB->res.boxlist));
if( box4->c != PICTURE ){
x0 = box4->x0; x1 = box4->x1;
y0 = box4->y0; y1 = box4->y1;
i++;
if (JOB->res.avX * JOB->res.avY > 0) {
if (x1 - x0 + 1 > 4 * JOB->res.avX
&& y1 - y0 + 1 > 4 * JOB->res.avY) continue; /* small picture */
if (4 * (y1 - y0 + 1) < JOB->res.avY || y1 - y0 < 2)
continue; // dots .,-_ etc.
}
if (x1 - x0 + 1 < 4
&& y1 - y0 + 1 < 6 ) continue; /* dots etc */
JOB->res.sumX += x1 - x0 + 1;
JOB->res.sumY += y1 - y0 + 1;
JOB->res.numC++;
}
} end_for_each(&(JOB->res.boxlist));
if ( JOB->res.numC ) { /* avoid div 0 */
JOB->res.avY = (JOB->res.sumY+JOB->res.numC/2) / JOB->res.numC;
JOB->res.avX = (JOB->res.sumX+JOB->res.numC/2) / JOB->res.numC;
}
if (JOB->cfg.verbose){
fprintf(stderr, "# averages: mXmY= %d %d nC= %d n= %d\n",
JOB->res.avX, JOB->res.avY, JOB->res.numC, i);
}
return 0;
}
/* ---- analyse boxes, find pictures and mark (do this first!!!)
*/
int detect_pictures(job_t *job) {
int i = 0, x0, y0, x1, y1, num_h;
struct box *box2, *box4;
if ( job->res.numC == 0 ) {
if (job->cfg.verbose) fprintf(stderr,
"# detect.C L%d Warning: numC=0\n", __LINE__);
return -1;
}
/* ToDo: set Y to uppercase mean value? */
job->res.avY = (job->res.sumY+job->res.numC/2) / job->res.numC;
job->res.avX = (job->res.sumX+job->res.numC/2) / job->res.numC;
/* ToDo: two highest volumes? crosses, on extreme volume + on border */
if (job->cfg.verbose)
fprintf(stderr, "# detect.C L%d pictures, frames, mXmY= %d %d ... ",
__LINE__, job->res.avX, job->res.avY);
for_each_data(&(job->res.boxlist)) {
box2 = (struct box *)list_get_current(&(job->res.boxlist));
if (box2->c == PICTURE) continue;
x0 = box2->x0; x1 = box2->x1;
y0 = box2->y0; y1 = box2->y1;
/* pictures could be of unusual size */
if (x1 - x0 + 1 > 4 * job->res.avX || y1 - y0 + 1 > 4 * job->res.avY) {
/* count objects on same baseline which could be chars */
/* else: big headlines could be misinterpreted as pictures */
num_h=0;
for_each_data(&(job->res.boxlist)) {
box4 = (struct box *)list_get_current(&(job->res.boxlist));
if (box4->c == PICTURE) continue;
if (box4->y1-box4->y0 > 2*(y1-y0)) continue;
if (2*(box4->y1-box4->y0) < y1-y0) continue;
if (box4->y0 > y0 + (y1-y0+1)/2
|| box4->y0 < y0 - (y1-y0+1)/2
|| box4->y1 > y1 + (y1-y0+1)/2
|| box4->y1 < y1 - (y1-y0+1)/2) continue;
// ToDo: continue if numcross() only 1, example: |||IIIll|||
num_h++;
} end_for_each(&(job->res.boxlist));
if (num_h>4) continue;
box2->c = PICTURE;
i++;
}
/* ToDo: pictures could have low contrast=Sum((pixel(p,x,y)-160)^2) */
} end_for_each(&(job->res.boxlist));
// start second iteration
if (job->cfg.verbose) {
fprintf(stderr, " %d - boxes %d\n", i, job->res.numC-i);
}
calc_average();
return 0;
}