Giz Explains: How QR Codes Work, And Why They Suck

QR codes are a technology that desperately wants our attention. They appear everywhere from supermarket shelves and magazines to hiking trails and tombstones. Never heard of a QR code? You're looking at one right now. Scan the image at the top of this article, and it will open a link to the mobile version... of this article. Very meta.

That's a pretty typical example of a QR code — occasionally useful but often pointless. Either way, these plucky information sources are routinely ignored, and usually reviled. Here's where the next big thing in scannable coding went so horribly wrong.

Quick Response code is the trademark name for the two dimensional barcode system. It was originally invented by Denso Wave, a Toyota subsidiary, in 1994 as a way to track vehicles as they were assembled, and to scan components at high speeds. While Denso Wave does hold the patent on the technology, it has granted free licence on it, going so far as to publish the spec online and allowing anyone to use it.

The conventional one dimensional barcodes used on virtually every consumer product are mechanically scanned. That is, they're read by physically bouncing a narrow beam of light onto the code, which can be interpreted using the pattern of light reflected off the white gaps between the lines.

QR codes, on the other hand, can not only hold 100 times more data than 1D barcodes — they can also be digitally scanned. The block of smaller black and white squares is read by a smart phone's image sensor, then interpreted by the system processor. The three large squares act as alignment targets, while the smaller square in the remaining corner acts to normalize the size and angle of the shot. As you can see from the image on the left, the blue strips near the alignment squares contain formatting information, and the remaining yellow area is the actual data that's converted into binary code and checked for errors before being displayed. The encoded data can be interpreted as one of four primary modes — numeric, alphanumeric, byte/binary, and Kanji. Other forms of data can also be displayed with the appropriate extensions.

As QR code technology evolved, it began to contain more and more information. The initial version was 21 x 27 pixels and held just 4 characters worth of data. The most recent version is 177 pixels square, and it holds over 1852 characters — enough for a few pages worth of information.

QR codes have long since expanded their usefulness beyond the automotive industry. They're used today in everything from inventory tracking, to shipping and logistics, to online ticketing (Fandango is a big fan). Bands put them on fliers to link to their videos on YouTube, or to load your calendar with reminders for upcoming shows. Businesses use it to integrate Google Maps directions on their business cards, automatically load their web page, or send a text/email to the company helpline. One enterprising wildlife refuge in Sanibel, Florida, has gone so far as to install the codes on signs along hiking trails and load them with information about the local fauna.

So with all these new and interesting ways to use this burgeoning technology — which, coincidentally, got a boost recently, when it was announced that the iPhone 5 would not include the competing NFC system — why aren't they more popular? According to Comscore, as of December 2011, only 20 per cent of Americans, 16 per cent of Canadians, and 12 per cent of Spanish and UK smartphone owners actually use QR codes at all.

In part, it's because advertisers have attached themselves to QR like it's a golden teat. The rate of QR codes in magazine ads rose by five per cent last year — from 3.6 to 8.4 per cent, according to marketing firm Nellymoser. You can find QR codes in stores, billboards, subway ads, posters, and magazines. "It's an effort to convey the appearance of being tech savvy," Thaddeus Kromelis, a strategist at WPP's (WPPGY) Blue State Digital, told Business Insider. Unfortunately, most consumers aren't buying it.

"Advertisers are looking at every way possible that they can connect with consumers," said Forrester Research analyst Patti Freeman Evans. "Consumers aren't saying, ‘Oh, I really want to be able to connect with companies and brands.'" As such, the primary use of QR codes last year was actually for product scanning — either to recieve further information on a product or a coupon/reward — and was primarily done at home.

This is due largely to the inherent limitations that QR suffers from. The system needs a steady hand to take the shot, the proper QR app to interpret it, and a data connection to load the web page and content. So when advertisers put QR codes on freeway billboards, or on subway ads where there is little cell reception, and expect users to then go through the trouble of installing an app just to be taken to the desktop version of the corporate website, it's little wonder why nobody bothers with it.

Thick-headed advertisers aren't the only drawbacks to QR codes, though. The codes can also be used to transmit malicious code, in what's known as "attagging". Since anyone can create the codes, it's easy to write a bit of malware, put it in a QR code, and slap that code over a legitimate tag. Some sap scans the bad code and, if his permissions are set too loosely, the code could give itself access to everything from the camera to the contacts to the GPS data. Or it could send the browser to an infection site loaded with browser exploits. The phone an become part of a bot net, or be used to send unauthorised texts — hackers in Russia once used QR to commandeer phones to send $US6 international SMS messages.

And of course there's the open source issue — great for developers, but not so terrific for the end users just trying to read the things. There are multitudes of QR readers in every app store, and all of them offer a slightly different user experience. None of the big three (iOS, Android, or WP7) offer a native app. Plus, there is no dominant brand of reader. So users are stuck picking QR readers essentially at random, hoping for the best.

All that hassle to (hopefully) look at a company's website or (possibly) have your security compromised? It's a combination of factors that doesn't do much to spur confidence in the technology — or enhance its adoption rate.

[Wikipedia - Forbes - QR Me - Statesman - 2D Code - Business Insider - Yellow Image: Swetake ]



    You know what, I never used a QR code in my life until the other day.

    I checked out this app that Nokia came out with, called photobeamer. And it looks really useful and awesome. You install the app on your phone, then on any screen with a browser you go to and scan the QR code, it then allows you to instantly show pictures from your phone to said screen.

      how much were you paid!

        Mate, when you make good enough products they market themselves.

          So why are you marketing it then?

            That's what that expression means. When you make a good enough product, they market themselves as in the consumers who buys them spreads the word about the product i.e. the company making the product does not need to market it as it is marketing itself.

    Windows Phone 8 comes with native QR code support, you just need to hit search/photo.

    Not that I ever use it.

    Windows Phone 7 also comes with native QR support.

      "None of the big three (iOS, Android, or WP7) offer a native app. "
      Like many things in WP7/8, QR codes are supported natively by the system, in this case the Search function.

    I think it took me about 2 years to realise QR Codes had nothing to do with Queensland Rail... :-\

    In countries where they are widely deployed and native to the phones they rock = Japan and Korea. The issue here, as usual, is adoption by handset software vendors - Google/Apple can (and probably will) fix this. You have also missed an important use-case - as code on the screen of phones - eg passbook - to scan by vendors - Widely used in north asia for ticketing. I will make a prediction - at some point in the next few years you will change your tune, because it's a technology that does work, just not in the English speaking countries yet.

      Europe too, quite a few of the rail journeys I took, I could just show a QR code on my phone as my ticket. Very useful for travelling with no easy access to printer.

    been using QR codes on my android phones for about 3 years, love them, love the tech love walking around and randomly seeing one on a wall without any reason... Scanning it to find some very cool sites/picture/info..

      Same. I also like those holes in the toilet walls and just seeing what happens if I insert random things into them.

    Well, at least they've finally stopped banging on about how QR is useless because of NFC.

    Exactly how i would explain QR Codes, in Short, they're Useless and Suck. Also find it frustrating, marketing people telling me, you need QR Codes in your business to succeed, yet cant explain to me how they actually work.

    I use QR codes for quickly logging into Airdroid. That's it.

    Andrew, please correct your article. Windows Phone 7 and 8 support and have from day one the use of QR codes in the visual search function. I personally have scanned hundreds of codes with it and find them useful to get to linked data rather than having to make a record of the URL and/or type it in.

      yeah its strange the entire article reads as "how great QR codes are" then a few lines at the bottom "and the reason they are bad is cos im useless at technology".

    At least they are not as bad as those Viewa and Genie apps - yes I'm looking at you pacific mags. That are basically fancy QR readers that use images instead. However, they take you to non-mobile versions to show you a video that has been coded in flash and will not work on any iphones. Well tested there...

    It's built into Google goggles, didn't that come installed natively on my galaxy?

    Jelly Bean natively supports QR codes. Using the google currents, press the settings button and voila! "Search with Camera".

    for the interested consumers, my vote for the best QR reader for iOS is "Scan"

      I disagree. The best QR app for iOS (due to extra functionality) is the google search app. Just tap the camera icon and away you go.

        Yes this works well, it's not natively obvious and I wasn't aware of this feature. +1

      nah built in image search in Windows Phone. Hit search button then the eye and your scanning not only QR codes but barcodes and text for translation

        Windows Phone doesn't run iOS, but thanks for sharing

    Reason QR codes are useful: You can't use NFC on billboards, it's cheap and doesn't need special hardware. I don't want to throw my phone at a billboard hoping that the data will transfer...

      Even if the billboard is nearby enough to not have to throw your phone (clearly with some kind of stretchy rope attached so you can retrieve it with the data :P) you're still hoping something dodgy doesn't get transferred using NFC.

    Windows Phone has Bing Vision baked into the search function since Mango. It'll scan Barcodes, QR Codes and can even identify books and CDs by their covers.

    I only got a Barcode/QR Code Scanner after adding Google's Authenticator to my Android phone. It is called Barcode Scanner (duh!) If I see a QR code, will scan it for fun to see what it is (so far nothing malicious). Successfully scanned the Kraay QR Code as well, without any issues due to the angel/clouds!

    And in other news web sites links suck. Thats all QR codes are for a mobile device..

    QR Code has wild applications in reports, mainly in creating qr code barcodes, like this qr code for Access reports.

    Yup indeed, I also think it is the basic function to scan QR codes using the app:

    Last edited 08/07/15 11:09 am

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