Cleaning QR Codes

At work we use QR Codes. It’s a pretty recent thing. For a few clients we used to scan pages of a file and then have the scanner operator stop what they were doing to give the TIFF file a meaningful filename. Now we have the clients supply cover sheets, generated with custom software, that contain QR codes. These then get processed after scanning and before the scan of the header sheet is discarded the indexing data is decoded using ZBar through an AutoHotkey script.

A few days ago we hit a problem. We’d scanned a few thousand pages but the script was unable to decode any of the indexing data from the QR codes. Not a single page. After looking into it I found that there were quality issues with the printing of the cover sheet. I could tell that the QR code was valid because the app I use on my mobile phone could read it fine, but ZBar could not. And ZBar is what matters – I wasn’t about to sit down decoding QR codes with my phone all day.

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