Re: free app to modify pdf files

On Sun, 15 Jun 2025 06:49:18 +0200, sobriquet wrote :

On the PC I've tried open office with a pdf extension, but that doesn't
seem to work very well, though it might vary depending on the type of pdf.

I've been "editing" PostScript & PDF for, oh, I don't know, twenty years or
so, starting with the acrobat distiller process in the early days... but we
need to keep in mind there are edits and there are edits - so a *lot*
depends on your desired edits, and, of course, whether the PDF is
essentially a bitmap or if it's what I'll call a "true pdf".

A 'true pdf' is a digitally created PDF and not a scanned image-only PDF.

When I need to edit scanned PDFs, I just use any decent image editor, many
of which work on the PDF itself but I generally convert to an image format
to edit and then I convert it back to a now-modified bitmap PDF when done.

Is your original to-be-edited document a true PDF or a scanned PDF?

I've been using Adobe Acrobat 6 for a very long time to make *minor*
changes to true PDF text; but there are free tools that do that now.

I'm just lazy since Adobe Acrobat 6 (the writer) has worked since 2003.

With the pdf that I tried, I wasn't very satisfied with the free online
version of ms-word either in the way it handled the pdf.

The best free PDF converter that I know of is calibre so if you haven't
tried it, you should because it's one of those must-have wondrous programs.

However, I agree with you that EVERY converter converts DIFFERENTLY, such
that it's like asking which color blonde makes for the best wife.

Every PDF conversion is different because of myriad differences, not the
least in the document itself that needs to be converted.

So, as you are doing, you just have to try each one, starting with those
most likely to result in decent output. I have tried a few and some are
great and most are not.
 

I'll give the free adobe pdf-editor webapp a try to see how that works.

I looked into my pdf logs and I didn't have any comprehensive report for
which free online tool does the CONVERSION to an editable format best, but
to give you an idea of what's available online, my logs show compression.

Since this is about conversion and modification, here's just a snippet.

[x] Best for FAST Online PDF compression >25MB
    https://docupub.com/pdfcompress/
    Keep the defaults and press the [Choose File] button
    Then press [Upload & Compress]
    Lastly click the link to view & download in browser

[x] Best for GREAT compression Online PDF compression >25MB
    But it has a bug so upload a tiny PDF & convert it first.
    https://www.adobe.com/ca/acrobat/online/compress-pdf.html
    First it has to completely fully upload before you do anything else
    Then select your compression level & press the "Compress" button
    Download (but it seems to take twice to get a download button)

[x] This sucks but purports to do many at once (but it sucks)
    https://pdfcompressor.com (only compresses 1%)
    Click [Upload Files] and let it compress it from that
    Then press "Download All"

But back to *editing*, what I'd do if the original is a true PDF is convert
with calibre first. And then I'd see what resulted. And try to edit that.

If the original is a scanned PDF, then I'd simply use an image editor, or,
if it's pure scanned text (no images or diagrams), I'd use a free OCR.