Generating QR codes in the terminal (with examples)
Use case 1: Generate a QR code
Code:
echo "Hello, world!" | qr
Motivation:
Generating QR codes in the terminal can be useful when you need to quickly share information with others. Instead of using an online service or downloading an application, you can generate a QR code directly in your terminal.
Explanation:
To generate a QR code, you can use the qr command in combination with the echo command. The data you want to encode as a QR code is piped into the qr command. In this case, we are piping the string “Hello, world!” into the qr command.
Example output:
The command echo "Hello, world!" | qr would output a QR code representing the text “Hello, world!” in your terminal.
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Use case 2: Specify the error correction level
Code:
echo "Hello, world!" | qr --error-correction=L
Motivation:
Error correction in QR codes ensures that the code can still be scanned even if it is partially damaged or distorted. By default, the error correction level is set to M (medium), but depending on the intended use of the QR code, a different level may be desired.
Explanation:
You can specify the error correction level by using the --error-correction flag followed by the desired level. The four possible error correction levels are:
- L (low): Allows recovery of up to 7% data loss.
- M (medium): Allows recovery of up to 15% data loss.
- Q (quartile): Allows recovery of up to 25% data loss.
- H (high): Allows recovery of up to 30% data loss.
In this example, we are specifying the error correction level as L.
Example output:
The command echo "Hello, world!" | qr --error-correction=L would output a QR code with error correction level set to low.
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