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Crowd Sourcing Broken QR Codes

humanqr.com

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Re: Crowd Sourcing Broken QR Codes

#21

Post by crazygringo »

darkwater wrote: post #11
ForHackernews wrote: post #6

The most common failure case I see for broken QR codes is it scans fine but it was created using some commercial link-bouncer service and they stopped paying the subscription fees so the redirect is dead.

This infuriates me. You are using a QR exactly to easily share a (long) link, why the hell you need to use a link shortener? Why is the market for small shops, restaurants, bars, small museums, small towns etc so riddled with technically incompetent people?

> easily share a (long) link, why the hell you need to use a link shortener?

Because it makes the QR code simpler (less "pixels") and therefore more robust. Given the same physical size, scratches affect it less, and a phone can read it from further away. You want to avoid long links in QR codes whenever possible.

The other thing is analytics, of course. You can generate 10 different small QR codes that lead to the same long URL, to find out where they're getting scanned, so you know which locations are popular and worthwhile and which ones are not.

And maybe don't criticize restaurant owners for being technically incompetent? I'm sure they would find you just as incompetent at cooking at scale.

Re: Crowd Sourcing Broken QR Codes

#22

Post by pimlottc »

darkwater wrote: post #11
ForHackernews wrote: post #6

The most common failure case I see for broken QR codes is it scans fine but it was created using some commercial link-bouncer service and they stopped paying the subscription fees so the redirect is dead.

This infuriates me. You are using a QR exactly to easily share a (long) link, why the hell you need to use a link shortener? Why is the market for small shops, restaurants, bars, small museums, small towns etc so riddled with technically incompetent people?

Being able to change the destination URL is one reason to use a redirect. Many users do not control their tech infrastructure, or have the knowledge to create redirects. This allows them to update or change content without changing their QR codes.

Re: Crowd Sourcing Broken QR Codes

#23

Post by ryukoposting »

viiralvx wrote: post #17

It's pretty cool that QR codes were created by a Japanese automotive company in order to address the limitations of scanning bar codes, mainly that the scans only worked with a certain orientation. [1] That being said, I believe bar codes have the UPC number below it in case the code itself is damaged. Could QR codes have a similar textual encoding to identify them? And would that even fit legibly in the square? [1]…

QR codes also encode text, just like UPC-A. As far as I'm aware, no barcode reader can actually interpret the letters at the bottom of the code. They're just there for a human failover when the barcode gets messed up.

With that in mind, there's nothing preventing you from putting the encoded text of a QR code below it. I have a QR code in my living room that guests can scan to connect to the Wi-Fi, and I put the SSID and password below the QR code on the same page. It's not the exact encoded string, but it serves the same purpose.

My first "real" job was working for an industrial automation company, where I did a lot of work on RFID and barcode readers. Barcodes (both 2D and 3D) are delightful things. There's an enormous variety out there, and you would never know unless you look closely, because they're so well-supported. I'd bet the barcode reader at your local grocery store can read at least 9 different encodings. Some are probably physically capable of reading QR (and other 3D codes like Aztec), but the firmware has been instructed to ignore them.

Re: Crowd Sourcing Broken QR Codes

#24

Post by Retr0id »

The biggest failure mode I've seen in-the-wild is from QR codes being attached to non-flat surfaces, e.g. wrapped around a lamp post, or on a car panel with "crease" in the bodywork (sorry, no specific examples on-hand)

AI is getting pretty good at depth estimation, and some phones even ship with LIDAR, so I think it should be feasible to correct for these automatically. Especially if you can get pictures from multiple angles.

Re: Crowd Sourcing Broken QR Codes

#25

Post by AStonesThrow »

wiradikusuma wrote: post #12
darkwater wrote: post #11

Earlier quoted context omitted.

This infuriates me. You are using a QR exactly to easily share a (long) link, why the hell you need to use a link shortener? Why is the market for small shops, restaurants, bars, small museums, small towns etc so riddled with technically incompetent people?

Sometimes, because the service sneakily shortens the link. I wanted to share a WIP whitelabel ticket sales platform ( https://pentas.id ) with a friend. I didn't have time to build the logic to generate QR code, so I just googled "online QR generator". I pasted my link, a QR code was generated. When I tried it using Pixel's Camera app, the preview is NOT my link. Although when I tap it, it eventually goes to my link.

> I didn't have [money], so I just [had someone else pay to generate a QR].

Fixed that for you. If you are using free stuff that you google-searched, then you're the product.

Re: Crowd Sourcing Broken QR Codes

#26

Post by OtherShrezzing »

Reading the QR code spec (or even just the wikipedia page) could help a lot here. A lot of the room on the code is taken up by metadata, rather than output-data. The output data is repeated lots of times across the code (this is why you can have a brand logo right in the middle of the code).

Repairing the metadata parts & iterating over each of the version number should make the overwhelming majority of broken QR codes usable again.

https://en.wikipedia.org/wiki/QR_code#/media/File:QR_Code_St...

Re: Crowd Sourcing Broken QR Codes

#27

Post by Karliss »

OtherShrezzing wrote: post #26

Reading the QR code spec (or even just the wikipedia page) could help a lot here. A lot of the room on the code is taken up by metadata, rather than output-data. The output data is repeated lots of times across the code (this is why you can have a brand logo right in the middle of the code). Repairing the metadata parts & iterating over each of the version number should make the overwhelming majority of broken QR cod…

Qr codes have some redundancy but nowhere near "repeated lots of time". Not even twice. More realistically there is 5-30% of redundancy and some very clever math to allow any individual part of data (not neceserily any part of qr code)to be damaged up to certain percentage.

Re: Crowd Sourcing Broken QR Codes

#29

Post by echoangle »

OtherShrezzing wrote: post #26

Reading the QR code spec (or even just the wikipedia page) could help a lot here. A lot of the room on the code is taken up by metadata, rather than output-data. The output data is repeated lots of times across the code (this is why you can have a brand logo right in the middle of the code). Repairing the metadata parts & iterating over each of the version number should make the overwhelming majority of broken QR cod…

The data isn’t repeated, it’s using Reed-Solomon-coding and maximum redundancy is only 30% extra data.
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