Fairly Positive

Reading Telepen Barcodes

The Library at the University of Bristol uses Telepen barcodes for stock management. In the m-biblio project I’d like to be able to read the barcodes within the smartphone application we are creating. I’m looking at using the ZBar bar code reader, which also includes an iPhone SDK. ZBar supports a number of barcodes implementations, including EAN-13/UPC-A, UPC-E, EAN-8, Code 128 and QR Codes. However, it doesn’t support the Telepen barcode symbology. I’ve spent far more time that I’d like to admit into looking at how easy it would be to add a new decoder to the ZBar SDK to decode the Telepen symbology. It probably would have been a lot easier if I’d written a reasonable amount of C in the last eight years.

I’ve had some success implementing a new decoder that can successfully decode a number of Telepen barcodes of various sizes. For example, the following barcode was decoded by using the command line zbarimg utility:


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I’m planning to document what I’ve learnt and implemented over a series of blog posts.