OCR file size

Discussion for the End User use uf OCR in PDF-XChange Editor and Viewer

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OCR file size

Post by randomonia » Tue Nov 20, 2012 6:33 pm

I am so happy you added OCR! Previously, to get a word searchable pdf I had to use a slow scanner w/ OCR software. Now I can use our speedy copier/printer/scanner and scan a document in seconds rather than minutes, but the resulting file is not searchable. Your OCR feature makes it so! Capt. Picard would be happy :wink:

A question: I've generally found that searchable pdf's created using OCR software are much smaller than the same document scanned as an image (e.g., 80k vs 400k). I was hoping your OCR feature might make the file smaller but it doesn't seem to be the case. Is this there anyway to make the file smaller?

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Re: OCR file size

Post by Walter-Tracker Supp » Tue Nov 20, 2012 7:04 pm

There are a couple of options which can reduce file size in the resulting PDF.

See the two attached screen shots for the location of these settings in the OCR dialog.

1. Preserve original content and add text layer - this keeps the original image intact and adds text on top of it. In some cases this results in a lower file size, since the alternative replaces the current page with a slightly altered copy (which may be, in some cases, larger).

2. Image quality: lower DPI means lower file size. This may result in loss of image quality from the original scan, but in many cases it won't be noticeable. If you scan at higher DPI for more accurate OCR (e.g. 150 or 300 DPI), then you can use this setting to reduce the image size after OCR and consequently reduce file size. In a test I ran here, a 300 DPI input document which used 14 MB of disk space was reduced to 1.5 MB with image quality set to 72 DPI. Be sure to select "Convert page content to image only ... ", in the PDF Output field, to enable this option.

We have also developed some new output features, but you will have to wait until our next major release which will be coming soon.

Hope this helps
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Posts: 5
Joined: Tue Nov 20, 2012 6:00 pm

Re: OCR file size

Post by randomonia » Wed Nov 21, 2012 8:01 pm

Thanks so much! My document recipients will be happy :D

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Paul - Tracker Supp
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Re: OCR file size

Post by Paul - Tracker Supp » Wed Nov 21, 2012 8:42 pm

If posting files to this forum - you must archive the files to a ZIP, RAR or 7z file or they will not be uploaded - thank you.

Best regards

Paul O'Rorke
Tracker Support North America

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