TechTips: High Capacity Bar Codes
An academic librarian hands out a one page summary sheet at a library orientation program. Glancing down, an attendee notices a weird looking bar code placed at the bottom of the page. Taking out their mobile device, the attendee photographs the bar code and software converts the image into an Internet accessible address. The device suggests that the attendee go to the address in the device’s web browser. After agreeing, the browser is launched and the attendee is taken to the linked content. The bar code enabled the mobile device to connect the attendee from printed to online content.
Perhaps the most significant technology impacting the delivery of library services is the mobile Internet. There is a growing role for libraries to offer tools and that take advantage of mobile technologies to help users discover and connect to licensed content, library services and resources. One of the tools emerging that can help to connect users to the library using the mobile Internet is the high capacity bar code (HCB).
The typical bar code consists of varying width black vertical bars and white spaces, with different combination of the bars and spaces representing different characters. A scanner’s photocell detector converts the bars (absorbed light) into a high electrical signal and the spaces (reflected light) into low electrical signal. This completed signal is decoded into the characters that the bar code represents and passes them to the computer in a traditional data format.
Libraries use a variety of bar codes formats with each being capable of storing approximately 20 digits. These bar codes simply act as a reference number which a computer uses to look up an associated record. A bar code on a library book contains only an item number. When read by a scanner at checkout, the ILS finds the item record associated with the item number. The item record - not the bar code - contains the item’s descriptive information. The ILS associates the item record with the customer record, which is also accessed by scanning a bar code on an ID.
While conventional bar codes can store about 20 digits of information, a single HCB is capable of handling nearly 8,000. Characters can include numeric and alphabetic characters, symbols, and binary data. They can contain descriptive information, images, or URLs which can connect to different web sites based on time, day of week, or customer preferences. They are also scalable so they can be read them in various levels of magnification – only limited by the resolution of the available printing and imaging techniques. HCBs are quite durable since the can still be readable with up to 30% of the code to be obscured or removed by dirt, marks or damage.
One type of HCB is the QR code (quick response), an established ISO (ISO/IEC18004) standard.
A few possible uses for HCBs in libraries quickly come to mind - codes on books, journals, and even journal articles could link customers directly to bibliographic information, reviews, or additional networked support materials. Codes on devices could lead customers to help and tip sheets. Codes on promotional and marketing materials could lead customers to the library web site. Codes on handouts could direct customers directly to databases, a journal article or a current bibliography.
While HCBs are widely used in Asia, the U.S. has been slow in adopting the technology primarily due to the availability for code readers fopr camara phones on the market here. But this is already changing. There are sites are available to identify a readers, like i-nigma or zxing.
Resources:
Educause. The 7 Things You Should Know About QR Codes
How Stuff Works. How UPC Bar Codes Work
1 comment March 23rd, 2009
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