Scan PDF's for Accessibility
In order for users of assistive technologies to be able to access the contents of a scanned document, it must first be run through an OCR (Optical Character Recognition) scan, which will convert the file to standardized text. Assistive technologies have the capabilities of reading PDF files created from scanned hard copies of documents, but only if the quality is monitored.
Required software and equipment to create accessible PDF’s are:
- Scanner with appropriate software
- Adobe Acrobat 8 Pro (or a later version)
Do not use the scanner for making an accessible PDF from a book. Photocopy the book pages first for better quality.
Your photocopy of the text needs to be as high quality as possible. Letters should be clear, not blurry; the text should be square on the photocopied page, and not angled or crooked. Avoid “copy of a copy” whenever possible. Blurry lettering or text that is crooked will create challenges for character recognition.
When scanning, make sure the scanner is set to scan at 250 DPI or better. The default DPI on the Goldfarb Library scanners at Brandeis is 300 DPI.
Using the HP 8300 Series scanners at Brandeis' Goldfarb Library
Step 1: Use a photocopier to get the best quality image possible from a book. Make sure that the text is not cut off or blurred on the margins.
Step 2: Load the document into the top feeder of the scanner.
Step 3: Open Adobe Acrobat Pro (available through the Start Menu > Programs).
Step 4: Choose “Create PDF” from Adobe Acrobat menu.
Step 5: Choose “Create PDF from Scanner” from next menu. Chose the HP Scanjet 8300 series as your scanner.
Step 6: The scanner program will launch, along with an options window for your scan.
Step 7: Check “Make a PDF/A Compliant” in the Options menu.
Step 8: Check “Make Searchable (Run OCR)” and check “Make Accessible” in the Text Recognition and Metadata menu.
Step 9: Click the “Scan” button. Load more pages to scan as needed.
Windows or Macintosh
In addition to PDFs created by this method, scans saved as Microsoft Word documents or generic text documents are also accessible.
Scanners and software are housed at the Brandeis University Library to create accessible PDFs. Scanners are currently located in the Information Commons of the Goldfarb Library.
If you wish to create your own scanning station, a basic scanner (no document feeder) costs approximately $200. To obtain a licensed copy of Adobe Acrobat Pro, see the options on the LTS Knowledge Base.
Persons with both documented and undocumented disabilities can use accessible PDFs in conjunction with appropriate reading software to assist them in meeting course reading requirements. Individuals who prefer to learn by listening rather than reading may also benefit.
Some text formats make it more difficult for Adobe to convert a scanned text into an accessible PDF format. Many images, text that is upon a shaded background, and text that is in table format is generally difficult for assuasive technologies to read. These guidelines may not produce %100 percent accessible text.