This would have been useful a few weeks back, especially the error correction part! I was visiting an unmanned business (no-one around) and my phone was dead.

This would have been useful a few weeks back, especially the error correction part! I was visiting an unmanned business (no-one around) and my phone was dead. I wanted to connect to the wireless but the WiFi sign had only a QR code and no plain text password. I didn't have a QR code scanner on my computer. One of my services uses a QR scanner on the web but I didn't have that project cloned on my MacBook. Regardless I scanned dependencies of dependencies hoping that some useless NPM dependency or some python package would have a QR code scanner but to no avail. In my search at least I found (several) parsers which knew how to scan the QR code (exactly what the article is describing) from a picture but no code to go from an image to the binary data. I didn't have OpenCV or any other library I'm familiar with to process images and I deemed it hard to do something without documentation - so I took a photo with PhotoBooth and started converting the picture manually square by square into 0 or 1. A few minutes later (and plenty of double checking) I had the data and I piped it into one of the parsers et voilà, I had internet.