[PDFBOX-3464] character height 3 times higher than expected

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Component/s: Text extraction
• Assignee: Unassigned
• Reporter: Roman
• Created: 16/Aug/16 09:17
• Updated: 27/May/19 16:50
• Resolved: 24/Aug/16 16:35

Description

The issue basically same as PDFBOX-2749, but wrong sample was attached to it by mistake. Correct PDF is attached here.

The core of the problem is that font height for this specific font is determined incorrectly, please see code with comments below.

The issue was reproduced on Pdfbox 1.8.4, but as we tested before, same result we get on 1.8.9 and 2.0 versions.

public class Extractor extends PDFTextStripper {
//<...CUT...>
	protected void writePage() throws IOException {
		for (List<TextPosition> textList : charactersByArticle) { //charactersByArticle was inherited from base class
			Iterator textIter = textList.iterator();
//<...CUT...>
			while (textIter.hasNext()) {
				TextPosition position = (TextPosition) textIter.next();
//<...CUT...>
		PDFontDescriptor fontDescriptor = position.getFont().getFontDescriptor();
//<...CUT...>

		float yscale = position.getTextPos().getYScale();
		float asc = Math.abs(fontDescriptor.getAscent() / 1000 * yscale);
		float rh = Math.abs(fontDescriptor.getFontBoundingBox().getUpperRightY() / 1000 * yscale);

		float desc = Math.abs(fontDescriptor.getDescent() / 1000 * yscale);
		float capHeight = Math.abs(fontDescriptor.getCapHeight() / 1000 * yscale);
		if (capHeight == 0)
			capHeight = position.getHeight();

		float h = (rh + Math.max(Math.max(capHeight, position.getHeight()), asc)) / 2;

//"h" evaluates to 37.39 (should be between 11 and 12)
//"desc" evaluates to 2.664
//"capHeight" evaluates to 37.39
//"position.getHeight()" evaluates to 33.48

Issue Links

• is duplicated by: PDFBOX-4480 Problem extracting text in newline characters and spaces beetween words
• is related to: PDFBOX-4553 Break of backward compatibility from 2.0.14 to 2.0.15