Line Height problem when converting from epub to pdf

[valida]

HI

I am converting a lot of epub to pdf (among other things, to take advantage of the highlight feature).

But the conversion process increases the line height so when I select a line and highlight it, the highlight goes over the line above and the line below.

See how the highlights overlap:




Whereas on other pdf, the overlap is almost none existant:



I have tried to change the Line Height, the Minimum line height and the line size (in look and feel) and also the font size, font type but I always get these overlaps.

So which settings should I change so my Pdf highlights doesn't overlap on the lines above and below?

[kovidgoyal]

PDF has no concept of line height. PDF just contains individual glyphs drawn at specified screen locations. How highlights are drawn depend entirely on what program you are using to view/annotate the PDF. You'd have to ask that programs developers about why the highlight looks like that.

[valida]

Thanks for your reply! I used Adobe Acrobat as a pdf reader. What is strange in your answer about pdf not having line height is that both of the pdf shown above have been created via calibre from the same epub (but with different conversion settings, I lost the settings I used for the pdf with the none overlapping highlights).

Because I didn't change Adobe Acrobat settings, that the source is the same and the only that changed between the two pdfs are the conversion settings in calibre, I was looking at the calibre settings as the culprit.

But what you seems to say is that, the conversion process as no control over the highlight heights, is that correct?

[kovidgoyal]

Yes, that is correct.

[dwig]

Originally Posted by valida

Thanks for your reply! ...both of the pdf shown above have been created via calibre from the same epub (but with different conversion settings, I lost the settings I used for the pdf with the none overlapping highlights).
...

as a note that might help working out what difference existed in the settings for the two PDFs:

The second, older, PDF that seems to have "properly sized" highlights uses a different font and displays horrid kerning while the first PDF displays very nice kerning. This makes it seem that at some point there was a font substitution. This likely has occured in the PDF reading app when either there was no embedded font or the embedded font couldn't be used.

[kovidgoyal]

Yeah I would guess it is font related. PDF files generated by calibre have embedded and subsetted fonts in them. It's likely that the PDF viewer calculates highlight height based on the font metrics of the embedded font.

[BetterRed]

@valida - Adobe Acrobat ain't the only kid on the block that can highlight text. Some of the others have the ability to set the 'thickness' of the highlight pen, IIRC the PDFill PDF reader/editor (Windows) has that feature.

BR

[valida]

I could solve this by simply "printing" the pdf (as another .pdf) with the problematic line-height.

So, open your pdf, go to file, print, leave everything as it is (page = all, size = fit) and press ok.

Somehow, the print process fix the line-height. I use Adobe Acrobat.