Feature to compare two PDFs (#enhancement)

[wandt0n]

I'd like to be able to compare two PDFs using PDFSam. My proposal:

• Splitview
• 3 distinct colors: Added, Removed, Changed
• It should detect: Changed Text, changed size of embedded content (as comparing images pixel by pixel might be stressful)
• It should ignore: Whitespaces, changes in font, changes in textstyle, pagebreaks, page numbers

That's just how I imagine such feature and I'd be glad to have this feature no matter the details.

[mara004]

Comparing PDF documents is very complex and likely outside the design goals of PDFSam Basic. Maybe you'll want to consider DiffPDF ?.

[wandt0n]

Thanks for the suggestion. And yeah, I assumed that as well. But since I already use PDFSam and it is opensource (DiffPDF is not), I thought I'd just propose this. This issue may be closed by an active contributor. I actually compared ~10 products, both free and fee-based, and couldn't find any opensource tool that is actively maintained. There are some like from vslavik, but they just render both pdf's on top of each other and that is no use to me. So closed-source it is, apparently.

[mara004]

(DiffPDF is not)

It used to be open-source (GPL). Linux distribution maintainers are now taking care of the codebase (they updated it to Qt5, for instance). If you are using a Debian-based distribution (e. g. Ubuntu 20.04), it should have DiffPDF available in the repository. Although not actively maintained, it works pretty well for me. For Windows, I think the last official open-source release (2.1.3) is still available as portable app. If you want the new Qt5 version, you'll have to build it from source, though.