+static void find_table_entry(Rect commod, int colno, Rect *cell) {
+ cell->tl.y= commod.tl.y;
+ cell->br.y= commod.br.y;
+ cell->tl.x= !colno ? commod.tl.x : colrightx[colno-1]+2;
+ cell->br.x= colrightx[colno];
+ debug_rect("cell", colno, *cell);
+
+ const RgbImage *ri= cim->rgb;
+
+ Rgb background= ri_rgb(ri, cell->br.x, cell->br.y);
+ long bg_count=0, light_count=0, dark_count=0;
+ Point p;
+ FOR_P_RECT(p,*cell) {
+ Rgb here= ri_rgb(ri, p.x, p.y);
+ if (here == background) bg_count++;
+ else if (here < background) dark_count++;
+ else if (here > background) light_count++;
+ }
+ long total_count= RECT_W(*cell) * RECT_H(*cell);
+ MUST( bg_count > total_count / 2,
+ MR(*cell);MIL(total_count);MIL(bg_count);
+ MIL(light_count);MIL(dark_count) );
+ if (bg_count == total_count)
+ return;
+
+ MUST( !!dark_count != !!light_count,
+ MR(*cell);MIL(total_count);MIL(bg_count);
+ MIL(light_count);MIL(dark_count) );
+
+ debugf("TABLEENTRY col=%d %d,%d..%d,%d bg=%ld light=%ld dark=%ld\n",
+ colno, cell->tl.x,cell->tl.y, cell->br.x,cell->br.y,
+ bg_count, light_count, dark_count);
+
+ Rgb foreground;
+ double fg_extra;
+ if (light_count) {
+ foreground= 0xffffffU;
+ fg_extra= +1;
+ } else {
+ foreground= 0;
+ fg_extra= -1;
+ }
+ int monochrome= 1;
+
+ FOR_P_RECT(p,*cell) {
+ Rgb here= ri_rgb(ri, p.x, p.y);
+ double alpha[3], alpha_mean=0;
+ int i;
+ for (i=0; i<3; i++) {
+ unsigned char here_chan= here >> (i*8);
+ unsigned char bg_chan= background >> (i*8);
+ unsigned char fg_chan= foreground >> (i*8);
+ double alpha_chan=
+ ((double)here_chan - (double)bg_chan) /
+ ((fg_chan + fg_extra) - (double)bg_chan);
+ alpha[i]= alpha_chan;
+ alpha_mean += alpha_chan * (1/3.0);
+ }
+
+ double thresh= 1.5/AAMAXVAL;
+ double alpha_min= alpha_mean - thresh;
+ double alpha_max= alpha_mean + thresh;
+ for (i=0; i<3; i++)
+ MUST( alpha_min <= alpha[i] && alpha[i] <= alpha_max,
+ MI(i);MRGB(here);MRGB(background);MRGB(foreground);
+ MF(alpha_min);MF(alpha[i]);MF(alpha_max) );
+
+ MUST( 0 <= alpha_mean && alpha_mean < 0.999,
+ MRGB(here);MRGB(background);MRGB(foreground);
+ MF(alpha_mean); MF(alpha[0]);MF(alpha[1]);MF(alpha[2]); );
+ int here_int= floor((AAMAXVAL+1)*alpha_mean);
+ assert(here_int <= AAMAXVAL);
+ if (!(here_int==0 || here_int==AAMAXVAL)) monochrome=0;
+ cim->d[p.y * cim->w + p.x]= '0' + here_int;
+ }
+
+ debug_rect("cell0M", colno, *cell);
+
+ require_rectangle_r(*cell, "0123456789", __LINE__);