A standard way to avoid this is by making the image URL http://lilqr.com/qr?rand=[nonce], where you'd generate the nonce randomly on each page load. You can ignore it on the server of course.
Feel free to suffix the URL with a random get-varaible, as this wont affect the service more then ensuring that proxies and cache hungry browser are less likely to cache the image.
My first thought was that it would generate a QR code for any string you provide, through url hacking. (i.e anything after the domain name is used as the string to encode) - This doesn't seem to be the case.
Very little instruction on the website, nothing on twitter, and no info here… Could you shed a little light please?
EDIT: As tiwilliam informed me, it uses the HTTP referer to create a QR code that contains a link back to that same HTTP referer. If it is not present, the default is lilqr.com.
It's a nice idea, but I don't see the value in having a QR code that links to the page you are already on? A bit more explanation is still necessary :)
I have no idea what this is used for. I'm 1/5th of the way down http://en.wikipedia.org/wiki/QR_code and still have no idea how this applies to websites. Most people who don't know aren't going to take time to go research it.
In a sentence: I have no idea what value benefit this has for me.
I'm telling you this because I want you to succeed, and if you want to gain traction outside if the HN bubble, then you'll probably want to appeal to regular people.
Still, a more explicit api would be great.
Ah, I think I see your point now. The hypothetical website doesn't have an associated mobile app. If I'm reading the site on my laptop and want to switch to my phone, I could scan the QR code rather than typing in the url.
Turns out there is one -- looks pretty handy! https://chrome.google.com/webstore/detail/bcfddoencoiedfjgep...
I wish someone would create a browser extension (Rapportive, this one is for you!) that would create a QR code for contact info from a person's email signature. If I want to quickly add someone's info from an email to my phone and call them, it's so much easier to scan a QR code than to deal with Address Book and then sync my phone.
A very common usage scenario for me: I'm in the midst of reading a couple of webpages (most likely very heavily commented HN articles) and suddenly, I realise my train is arriving soon and I've to make a quick dash to the station. Once I get on the train, fire up FF on my phone, sync and in an instant, all my open tabs on my work computer is on my mobile.
Hmm, that might be nice project to try out some extension programming.
Saved me from some work. :-)
<img id="qrCode" />
document.getElementById("qrCode").src = "https://chart.googleapis.com/chart?chs=150x150&cht=qr... + window.location + "&choe=UTF-8";
I'm going to HAVE to play with this some more. This evening my wife and I were driving around looking at houses for sale and I was thinking that every For Sale sign should have a big old QR code on it that takes you directly to a webpage for that specific house with the listing price and details about the house. I shouldn't have to jump out and grab an info sheet, I should be able to scan the big ol' QR code from my car and see the details about the house.
my $url = 'http://news.ycombinator.com/';
print "Content-type: image/png\r\n\r\n";
BTW, it's always good to see another perlmonger.
Would be nice to have some way to put in the URL on a page and have it generate PNGs of different sized codes, like for printing on a brochure or poster.
Do you do any sort of detection of things like detecting that www.foo.com/bar and foo.com/bar are the same page, so they can share a code? Maybe for advanced users almost like some kind of re-write rules so that requests for/from certain pages can be linked to a static QR code?
i wonder which other tools could be implemented that simple...
I see QR codes really taking off this year and next.
ps if anyone out there is interested in selling mobile websites for us, typical commission is around $300 and you do not need to know any coding. please contact me on skype or email@example.com