/**
* Returns the baseline of the current object at the given level.
* The baseline is the line that passes through (x1, y1) and (x2, y2).
* WARNING: with vertical text, baselines may be vertical!
*/
bool PageIterator::Baseline(PageIteratorLevel level,
int* x1, int* y1, int* x2, int* y2) const {
if (it_->word() == NULL) return false; // Already at the end!
ROW* row = it_->row()->row;
WERD* word = it_->word()->word;
TBOX box = (level == RIL_WORD || level == RIL_SYMBOL)
? word->bounding_box()
: row->bounding_box();
int left = box.left();
ICOORD startpt(left, static_cast<inT16>(row->base_line(left) + 0.5));
int right = box.right();
ICOORD endpt(right, static_cast<inT16>(row->base_line(right) + 0.5));
// Rotate to image coordinates and convert to global image coords.
startpt.rotate(it_->block()->block->re_rotation());
endpt.rotate(it_->block()->block->re_rotation());
*x1 = startpt.x() / scale_ + rect_left_;
*y1 = (rect_height_ - startpt.y()) / scale_ + rect_top_;
*x2 = endpt.x() / scale_ + rect_left_;
*y2 = (rect_height_ - endpt.y()) / scale_ + rect_top_;
return true;
}
// This method resolves the cc bbox to a particular row and returns the row's
// xheight.
int ShiroRekhaSplitter::GetXheightForCC(Box* cc_bbox) {
if (!segmentation_block_list_) {
return global_xheight_;
}
// Compute the box coordinates in Tesseract's coordinate system.
TBOX bbox(cc_bbox->x,
pixGetHeight(orig_pix_) - cc_bbox->y - cc_bbox->h - 1,
cc_bbox->x + cc_bbox->w,
pixGetHeight(orig_pix_) - cc_bbox->y - 1);
// Iterate over all blocks.
BLOCK_IT block_it(segmentation_block_list_);
for (block_it.mark_cycle_pt(); !block_it.cycled_list(); block_it.forward()) {
BLOCK* block = block_it.data();
// Iterate over all rows in the block.
ROW_IT row_it(block->row_list());
for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward()) {
ROW* row = row_it.data();
if (!row->bounding_box().major_overlap(bbox)) {
continue;
}
// Row could be skewed, warped, etc. Use the position of the box to
// determine the baseline position of the row for that x-coordinate.
// Create a square TBOX whose baseline's mid-point lies at this point
// and side is row's xheight. Take the overlap of this box with the input
// box and check if it is a 'major overlap'. If so, this box lies in this
// row. In that case, return the xheight for this row.
float box_middle = 0.5 * (bbox.left() + bbox.right());
int baseline = static_cast<int>(row->base_line(box_middle) + 0.5);
TBOX test_box(box_middle - row->x_height() / 2,
baseline,
box_middle + row->x_height() / 2,
static_cast<int>(baseline + row->x_height()));
// Compute overlap. If it is is a major overlap, this is the right row.
if (bbox.major_overlap(test_box)) {
return row->x_height();
}
}
}
// No row found for this bbox.
return kUnspecifiedXheight;
}
// Compute the distance from the left and right ends of each row to the
// left and right edges of the block's polyblock. Illustration:
// ____________________________ _______________________
// | Howdy neighbor! | |rectangular blocks look|
// | This text is written to| |more like stacked pizza|
// |illustrate how useful poly- |boxes. |
// |blobs are in ----------- ------ The polyblob|
// |dealing with| _________ |for a BLOCK rec-|
// |harder layout| /===========\ |ords the possibly|
// |issues. | | _ _ | |skewed pseudo-|
// | You see this| | |_| \|_| | |rectangular |
// |text is flowed| | } | |boundary that|
// |around a mid-| \ ____ | |forms the ideal-|
// |cloumn portrait._____ \ / __|ized text margin|
// | Polyblobs exist| \ / |from which we should|
// |to account for insets| | | |measure paragraph|
// |which make otherwise| ----- |indentation. |
// ----------------------- ----------------------
//
// If we identify a drop-cap, we measure the left margin for the lines
// below the first line relative to one space past the drop cap. The
// first line's margin and those past the drop cap area are measured
// relative to the enclosing polyblock.
//
// TODO(rays): Before this will work well, we'll need to adjust the
// polyblob tighter around the text near images, as in:
// UNLV_AUTO:mag.3G0 page 2
// UNLV_AUTO:mag.3G4 page 16
void BLOCK::compute_row_margins() {
if (row_list()->empty() || row_list()->singleton()) {
return;
}
// If Layout analysis was not called, default to this.
POLY_BLOCK rect_block(bounding_box(), PT_FLOWING_TEXT);
POLY_BLOCK *pblock = &rect_block;
if (poly_block() != NULL) {
pblock = poly_block();
}
// Step One: Determine if there is a drop-cap.
// TODO(eger): Fix up drop cap code for RTL languages.
ROW_IT r_it(row_list());
ROW *first_row = r_it.data();
ROW *second_row = r_it.data_relative(1);
// initialize the bottom of a fictitious drop cap far above the first line.
int drop_cap_bottom = first_row->bounding_box().top() +
first_row->bounding_box().height();
int drop_cap_right = first_row->bounding_box().left();
int mid_second_line = second_row->bounding_box().top() -
second_row->bounding_box().height() / 2;
WERD_IT werd_it(r_it.data()->word_list()); // words of line one
if (!werd_it.empty()) {
C_BLOB_IT cblob_it(werd_it.data()->cblob_list());
for (cblob_it.mark_cycle_pt(); !cblob_it.cycled_list();
cblob_it.forward()) {
TBOX bbox = cblob_it.data()->bounding_box();
if (bbox.bottom() <= mid_second_line) {
// we found a real drop cap
first_row->set_has_drop_cap(true);
if (drop_cap_bottom > bbox.bottom())
drop_cap_bottom = bbox.bottom();
if (drop_cap_right < bbox.right())
drop_cap_right = bbox.right();
}
}
}
// Step Two: Calculate the margin from the text of each row to the block
// (or drop-cap) boundaries.
PB_LINE_IT lines(pblock);
r_it.set_to_list(row_list());
for (r_it.mark_cycle_pt(); !r_it.cycled_list(); r_it.forward()) {
ROW *row = r_it.data();
TBOX row_box = row->bounding_box();
int left_y = row->base_line(row_box.left()) + row->x_height();
int left_margin;
ICOORDELT_LIST *segments = lines.get_line(left_y);
LeftMargin(segments, row_box.left(), &left_margin);
delete segments;
if (row_box.top() >= drop_cap_bottom) {
int drop_cap_distance = row_box.left() - row->space() - drop_cap_right;
if (drop_cap_distance < 0)
drop_cap_distance = 0;
if (drop_cap_distance < left_margin)
left_margin = drop_cap_distance;
}
int right_y = row->base_line(row_box.right()) + row->x_height();
int right_margin;
segments = lines.get_line(right_y);
RightMargin(segments, row_box.right(), &right_margin);
delete segments;
row->set_lmargin(left_margin);
row->set_rmargin(right_margin);
}
}
