Using book-scanning services, I have books scanned into pdf files as 300dpi images. Using Acrobat DC Pro, I run the Recognize Text tool within the Enhance Scans category (which actually decreases the file size). I then, within the Redact category, try to Remove Hidden Information or Sanitize Document, and the file size explodes upward. As a representative example, this is what happens:
Step 0: Book as received from scanning service: 19MB
Step 1: Book after running text recognition: 13MB
Step 2: Book after running Remove Hidden Information: 53MB
or: Step 2: Book after running Sanitize Document: 22MB
Incredibly, not only does the file size increase dramatically when removing information/sanitizing document, but, to put salt on the wounds, the image quality also decreases noticeably! This always happens, with no exception.
1) Why does this happen? Intuitively, I would think removing hidden information would actually reduce file size, especially if the image quality deteriorates.
2) Is there any solution to this?
3) Assuming there is no good built-in Acrobat solution, is there any third-party software alternative to sanitize pdf documents that doesn't cause file size to explode up?
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This is a known issue and we are working on it. As a workaround, you might try optimizing the pdf file to make it PDF version 1.7 and compatible with Acrobat 10.0 and later.
Thank You for your patience.
Hi, I optimized my file to make my PDF compatible with Acrobat 10.0 and later, but "Remove Hidden Information" or "Sanitize Document" still make the file size explode.
Is there any detailed steps that we can follow? Thanks!
Any updates on this?
Still an issue on Adobe Acrobat Pro 2017 Mac (17.11.30105)
Please refer to the following thread: forums.adobe.com/thread/1396892
This problem has been known for 4+ years! Please don't tell me that you are working on it if you're not actually working on it. Instead of copping out, how about you actually do the work?
Or please just tell me the truth: Adobe doesn't care enough to fix it so deal with larger file sizes or don't use the tool.
Known issue since January 2017, probably earlier. Nearing 2021, still not fixed, like nearly every other issue. Just experienced this same problem that I've been experiencing for years.
I just redacted and sanitized a couple of PDFs, and the file size stayed roughly the same, but the resolution of the display dropped drastically, to a fuzzy unusable lack of sharpness. So the whole redaction tool still isn't usable.
Or is there some way to preserve the quality of a PDF after it's been redacted and/or sanitized?
My file looks awful and the size is huge. I see this has been an issue for many years, when can we expect to see a fix to this issue?
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This issue is still present. We get file sizes that are ~3x the original, when we run Sanitize.
If we Optimize, we get to remove what we select and the file size stays roughly the same size or shrinks a bit.
Please fix this issue.