"Image to PDF" vs "Enhanced Scanned Pages"

[patrickm]

You have these two tools to work with scans: "Image to PDF" and "Enhanced Scanned Pages".

And they both have slightly different options and when I first use Image to PDF and then Enhanced Scanned Pages to get the best of both worlds the Image gets compressed two times which leads to reduced scan quality.

Can you please outline what the correct workflow is to apply all of these to my scan:

• Deskew
  Despeckle
  Background Removal
  Descreen
  Text Sharpening
  Fix content skew and page rotation
  Highest quality OCR

I mentioned here that OCR exist 3 times which adds to my confusion
[https://forum.pdf-xchange.com/viewtopic.php?f=70&t=37542]

Thank you,
Patrick

Image to PDF

Enhanced Scanned Pages

[TrackerSupp-Daniel]

Hello, patrickm

I mentioned this in the other topic, but the OCR functions are offered in both of these features because they share resources with our other applications, like the Editor. These are time-saving functions to be present here, and nothing more. The OCR results should be the same whether you run OCR as part of one of these two steps, or if you run them without OCR, and then add the OCR tool itself separately afterwards.

Generally speaking, you should not be trying to use both features in the same tool, for the exact reason of double compression you mentioned. The "image to PDF" tool is intended to convert an existing image format, such as PNG, to a PDF file, while the "Enhance scanned pages" tool is designed to attempt to "touch up" a scanned document page (descreening, removing background, etc). This process often helps, but in certain cases it can be detrimental, and you will need to observe how each documents output appears to be sure it is what you desired.

To enable all of those functions, you would need to use both actions (image to PDF, and "Enhance scanned pages"); at this point I should ask, are the images you are converting poor enough in quality that the need this treatment? if they are, it might be best to use a dedicated image editing software to manually touch up the files.
If the documents are already PDF files, and you do not need to convert from an image format, the "Descreen" function should act well enough as a "despeckle" function, so in that case you could simply use the "Enhance scanned pages" action.

Finally, regarding "OCR quality" Our OCR engine always processes at the same "output quality" the "accuracy" setting you see in these options is more so related to the quality of the current document Before OCR. If your document is already pristine and has never left the digital format, using Auto or "high" accuracy may be ideal. In most other cases, auto or "medium" should be used. In cases where the document is poor quality, or was scanned at a low DPI settings, then either Auto or "low" accuracy setting should be used. You may have noticed a pattern, the "auto" setting is good in all three scenarios, this is becuase it processes the original scanned image. The high, medium, and low, options may convert the image to a more appropriate DPI and process it like that, to try and get a more accurate result for the chosen accuracy level.

Kind regards,