
When Wifi goes down: Transfer files from Air gapped machines using QR codes - vinnyglennon
https://github.com/leonjza/qrxfer
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padde
This is cool.

I guess with high density QR codes, a decent display and a good cam you could
transfer a megabyte or more in a minute :D If both devices have front facing
cameras, such as smartphones, you could even have a real-time back channel
(duplex), and the receiving device could signal the sending device that a
certain "frame" got lost and needs to be retransmitted.

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coreyp_1
This is a beautiful idea. How much information does the QR code carry, and how
much is transfer boilerplate?

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th0br0
The maximum storage capacity seems to be 2953 bytes ([1]). Although that's
with error correction level L, so you can only read it as long as you have 93%
of all codewords.

[1]
[https://en.wikipedia.org/wiki/QR_code#Storage](https://en.wikipedia.org/wiki/QR_code#Storage)

