GNOME Bugzilla – Bug 556018
Reflow for small screens/windows
Last modified: 2018-05-22 13:25:26 UTC
Acrobat Reader for Windows, is able to reflow some PDFs for display on smaller screens. Paragraphs are given new line breaks, columns are moved one after the other, and so on. Otherwise, you have to zoom in and then scroll sideways.
Which screen is considered small?
A screen which can not fit the full width of the page without zooming out so much that the text is unreadable.
Doesn’t this depend on the PDF being a »Tagged PDF«, i.e., enriched with structural information? Does Poppler even recognize that?
I suppose no
Actually I find that acrobat reader 9 ("9.1.2 05/25/2009") (ubuntu package "acroread") *does* have reflow now - it's just not very obvious where to find it! Use "View | Zoom | Reflow" (or CTRL+4). It seems to work whether the PDF file is tagged or untagged... Note: This is not just an issue for "small" screens; it affects anyone with even mild visual impairment who can benefit from magnification that would otherwise result in a need for horizontal scrolling. This can easily happen on "full size" screens. I guess it would still be nice if evince also supported reflow, but it is not quite as critical as long as there is an alternative available.
Created attachment 139456 [details] how reflow looks in Adobe Reader I just tried this out with a two-column journal paper (Elsevier). Adobe Reader processed the file for more than a minute on full CPU utilisation. For every view. (Seems to be a hard problem.) And the results were less than usable. Since PDF doesn’t contain information about text structure and reading order it is not trivial to reconstruct the columns and boxes from the plain PDF.
Sorry, I should have been a bit more clear: I said that acroread reflow "seemed" to "work" on both tagged and untagged documents; but I have only done very limited testing of this, and if the document has any kind of complex structure (including even multiple columns) I would expect the results on untagged files to be pretty poor. But it *should* work somewhat OK, even for more complex documents, if they are properly tagged. I suspect this particular journal paper from Elsevier is not tagged (you can check via "File|Properties|Description"), but I am not sure if that is what is causing the problem here. From your screenshot, it looks like reflow is losing all interword spaces in this case; I don't know whether such a very strange behaviour would be associated with tagging or whether it is to do with some other aspect of the specific PDF coding in use here.
-- GitLab Migration Automatic Message -- This bug has been migrated to GNOME's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.gnome.org/GNOME/evince/issues/70.