QR codes

2007-10-16

I just found this cool mobile barcoder extension for firefox that displays so-called QR codes that encode the url of the page you are currently looking at. QR codes are like bar codes, only 2-dimensional. For example: QR code for my blog (generated using this site: http://qrcode.kaywa.com/)

It so happens that my Nokia N95 (hey, there’s some benefit in working for a market leading mobile phone manufacturer :-) ) includes a bar code reading application that is damn near useless reading old fashioned bar codes in dark supermarkets. The problem is partly with the optics in the camera which do not support macro mode photography very well (i.e. photographing subjects from something like 15cm doesn’t really work wel). A second problem is that while hovering with your camera over the barcode you generally block the light that falls onto it. This combined with real world situations where bar code equipped objects are generally indoors in possibly poorly lit places doesn’t make it easier. A final problem is that the old vertical bar codes are actually quite hard to scan properly with a camera since the thickness of the bars has meaning (four different bars) and the bars tend to be quite close together.

However, I just discovered the software handles QR codes displayed on a nice bright LCD screen a hell of a lot better. Just hold the camera about 30 cm from the screen, press scan code and almost instantly you have the url in the phone and can then proceed to open it in the S60 browser. QR is short for quick recognition and it really is quick. QR codes don’t have all the problems listed above and are basically optimized to be scanned using a camera. They include error correction. The three big squares are used for indicating the dimensions of the QR code to the software.

So, why is this nice? Well T9 is OKish for sending short messages to people with all vowels omitted but sort of sucks for entering urls. So if you quickly want to browse a url with your N95 (or any other phone with QR bard code scanning software), this is a pretty neat way to do it.