Read QR code from terminal
I am working on a C application that should display a QR code. Instead of writing GUI code, I thought to show it right on the terminal. However, standard QR code readers expect the code to be square, but when printed in a linux terminal, it looks rectangular.
How to solve this problem? Trying to print the code in a square form would probably be the best option to keep it compatible with standard QRC readers. To be honest, I don't even know if the QRC reader can interpret the code displayed by the terminal (it might be readable depending on the characters used).
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It depends on the exact font used and if your terminal supports characters, but I would try the following for every black square you need: ██
These are two U + 2588 FULL BLOCK characters. Then, for each white square, just use two regular spaces.
Edit: Just read Cong Ma's comment and related source code. Taking a quick look at this, it looks like they are using a variation of this idea, but instead use semi-blocked characters (▀ and) that print two lines at a time so that the output ends up at a quarter of the size my method is taller.
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