/segno

Python QR Code and Micro QR Code encoder

Primary LanguagePythonBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

https://app.travis-ci.com/heuer/segno.svg?branch=master

QR Code encoder and Micro QR Code encoder

Pure Python QR Code generator with no dependencies.

This package implements ISO/IEC 18004:2015(E) "QR Code bar code symbology specification" and produces QR Codes and Micro QR Codes with nearly no effort. It supports the Structured Append mode which splits a message across several QR codes.

Segno (Italian for "sign" / "symbol") provides several serialization formats like Scalable Vector Graphics (SVG), Encapsulated PostScript (EPS), Portable Network Graphics (PNG), Portable Document Format (PDF), Netpbm (PAM, PBM, PPM), LaTeX (PGF/TikZ), X PixMap (XBM), and X Bitmap (XPM) etc. None of these serializers require an external lib. Further, it provides several high level functions to create QR Codes which encode contact data (vCard, MeCard), EPC QR Codes, or WIFI QR Codes.

The project provides more than 1500 test cases (coverage >= 98%) to verify a standard conform QR Code and Micro QR Code generation acc. to ISO/IEC 18004:2015(E).

Unique features

import segno
qrcode = segno.make('Yellow Submarine')
qrcode.save('yellow-submarine.png')

Installation

Use pip to install segno from PyPI:

$ pip install segno

MacPorts

Segno is also available at MacPorts (MacPorts project page):

$ sudo port install py-segno

conda-forge

The library is also available at conda-forge (conda-forge project page):

$ conda install -c conda-forge segno

Debian 11 / Bullseye

$ apt-get install python3-segno

Debian 10 / Buster (backports)

$ apt-get -t buster-backports install python3-segno

Arch Linux

$ pacman -S python-segno

Usage

Command line

The command line script prints a QR code to the terminal:

$ segno "Comfortably Numb"

To serialize a QR code, use the "output" argument:

$ segno -o=raincoat.svg "Famous Blue Raincoat"
$ segno --scale 10 --dark darkblue --border 0 --output=fire.svg "Who by Fire"
$ segno --scale 10 --light transparent --output=miracle.png "Waiting for the Miracle"

Library

>>> import segno
>>> # Let Segno choose the minimal version and an optimal (maximal) error
>>> # level without changing the minimal version
>>> qrcode = segno.make('Up Jumped the Devil')
>>> qrcode.designator  # Returns the QR code version and the error correction level
'2-Q'
>>> qrcode.save('up-jumped-the-devil.png')  # Save as PNG
>>> qrcode.save('up-jumped-the-devil-2.png', scale=10)  # Scaling factor 10
>>> qrcode.save('up-jumped-the-devil-3.png', light=None)  # Transparent light modules
>>> qrcode.save('up-jumped-the-devil.pdf', scale=10)  # Save as PDF
>>> # SVG drawing the dark modules in "dark blue"
>>> qrcode.save('up-jumped-the-devil.svg', scale=10, dark='darkblue')

If the content to encode is small enough, a Micro QR code is generated:

>>> import segno
>>> qrcode = segno.make('RAIN')
>>> qrcode.is_micro
True
>>> qrcode.designator
'M2-M'

If this behaviour is not desired, the user may set micro to False

>>> import segno
>>> qrcode = segno.make('RAIN', micro=False)
>>> qrcode.is_micro
False
>>> qrcode.designator
'1-H'

Or use the factory functions segno.make_qr() which generates always QR codes (never Micro QR codes) or segno.make_micro() which returns always Micro QR codes (or raises an error if the content is too large for a Micro QR code).

>>> import segno
>>> qrcode_micro = segno.make_micro('THE BEATLES')
>>> qrcode_micro.designator
'M3-M'
>>> qrcode = segno.make_qr('THE BEATLES')  # Same content but enforce a QR Code
>>> qrcode.designator
'1-Q'
>>> # This won't work since the data does not fit into a Micro QR Code M1 - M4
>>> micro_qrcode = segno.make_micro('Nick Cave and the Bad Seeds')
Traceback (most recent call last):
    ...
DataOverflowError: Data too large. No Micro QR Code can handle the provided data

All factory functions use the same parameters to specify the desired error level, version, data mask etc., see Segno's documentation for details.

Documentation

Read the online documentation at <https://segno.readthedocs.io/>

Trademark

"QR Code" and "Micro QR Code" are registered trademarks of DENSO WAVE INCORPORATED.