QR(1) QR(1)
NAME
qr - generate QR code
SYNOPSIS
qr [ -LMQHna ] [ -v version ]
DESCRIPTION
Qr generates a QR code from the data it reads on standard
input. The QR code is generated as an image(6) on standard
output.
The -LMQH options set the level of error correction. -L is
the lowest and -H is the highest level. The default is -M.
The QR standard defines different sizes labelled version 1
to version 40. By default the smallest possible is chosen
automatically. The -v option forces the use of a particular
version.
By default bytes are encoded directly with no translation.
Coding efficiency can be increased by reducing the set of
legitimate characters using the -an options. The -n option
supports only numbers and the -a option supports letters,
numbers, spaces and the symbols `$%*+-./:'. Note that all
letters are converted to upper case. Both options ignore
any characters they do not recognize.
SOURCE
/sys/src/cmd/qr.c
SEE ALSO
International Standard ISO/IEC 18004.
BUGS
The standard specifies the use of JIS-8 encoding in the
default mode, however rumour has it that readers recognize
UTF-8.
The more advanced coding features (Kanji mode, extended
modes, switching modes midstream) are not supported.
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