9

I have a PDF file which I can select images to embed in. The customers are not technical so I do not want them to remove metadata themselves (e.g. GPS location of photos, etc). Will the PDF automatically remove them when they are embeded in the PDF.

For example, I have used PDFStreamer to find my embedded image and it is in base64: contentType="image/png" href="" [CONTENT in BASE64].

Maybe my question is if base64 image encoding contains metadata?

1 Answer 1

7

Yes, EXIF data may be saved, depending on how your PDF tools work.

As an example, you can take a JPEG with EXIF data, put it into LibreOffice Writer, then save that document as a PDF with "Lossless Compression" enabled and "Reduce Image DPI" disabled. If you then extract images from that PDF (there are many tools for this, I used an online one for speed) the JPEG EXIF data will still be there.

If you enable lossy JPEG compression, at least in LibreOffice's PDF export dialogue, it appears that the JPEG is recompressed to a new file with EXIF data stripped.

It is not difficult to remove EXIF data from images in Windows, and you should be able to talk them through the process. For each image, right click it, go to properties, go to the details tab, click the "Remove Properties and Personal Information" link at the bottom, select "Remove the following properties from this file", click the Select All button, then click OK.

1
  • Disabling "Reduce image resolution" (which had the value 300 DPI in my case) was enough to keep metadata, I did not need to enable "Lossless compression" for the PDF export in LibreOffice Writer. Then I was able to save the image with metadata from the PDF file with LibreOffice Draw and view the metadata with GIMP in the menu "Image -> Metadata -> View Metadata".
    – baptx
    Apr 22, 2021 at 9:53

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .