Project: qrcode

QR Code image generator

Project Details

Latest version
7.4.2
Home Page
https://github.com/lincolnloop/python-qrcode
PyPI Page
https://pypi.org/project/qrcode/

Project Popularity

PageRank
0.008260067829293588
Number of downloads
2243231

============================= Pure python QR Code generator

Generate QR codes.

A standard install uses pypng_ to generate PNG files and can also render QR codes directly to the console. A standard install is just::

pip install qrcode

For more image functionality, install qrcode with the pil dependency so that pillow_ is installed and can be used for generating images::

pip install "qrcode[pil]"

.. _pypng: https://pypi.python.org/pypi/pypng .. _pillow: https://pypi.python.org/pypi/Pillow

What is a QR Code?

A Quick Response code is a two-dimensional pictographic code used for its fast readability and comparatively large storage capacity. The code consists of black modules arranged in a square pattern on a white background. The information encoded can be made up of any kind of data (e.g., binary, alphanumeric, or Kanji symbols)

Usage

From the command line, use the installed qr script::

qr "Some text" > test.png

Or in Python, use the make shortcut function:

.. code:: python

import qrcode
img = qrcode.make('Some data here')
type(img)  # qrcode.image.pil.PilImage
img.save("some_file.png")

Advanced Usage

For more control, use the QRCode class. For example:

.. code:: python

import qrcode
qr = qrcode.QRCode(
    version=1,
    error_correction=qrcode.constants.ERROR_CORRECT_L,
    box_size=10,
    border=4,
)
qr.add_data('Some data')
qr.make(fit=True)

img = qr.make_image(fill_color="black", back_color="white")

The version parameter is an integer from 1 to 40 that controls the size of the QR Code (the smallest, version 1, is a 21x21 matrix). Set to None and use the fit parameter when making the code to determine this automatically.

fill_color and back_color can change the background and the painting color of the QR, when using the default image factory. Both parameters accept RGB color tuples.

.. code:: python

img = qr.make_image(back_color=(255, 195, 235), fill_color=(55, 95, 35))

The error_correction parameter controls the error correction used for the QR Code. The following four constants are made available on the qrcode package:

ERROR_CORRECT_L About 7% or less errors can be corrected. ERROR_CORRECT_M (default) About 15% or less errors can be corrected. ERROR_CORRECT_Q About 25% or less errors can be corrected. ERROR_CORRECT_H. About 30% or less errors can be corrected.

The box_size parameter controls how many pixels each "box" of the QR code is.

The border parameter controls how many boxes thick the border should be (the default is 4, which is the minimum according to the specs).

Other image factories

You can encode as SVG, or use a new pure Python image processor to encode to PNG images.

The Python examples below use the make shortcut. The same image_factory keyword argument is a valid option for the QRCode class for more advanced usage.

SVG

You can create the entire SVG or an SVG fragment. When building an entire SVG image, you can use the factory that combines as a path (recommended, and default for the script) or a factory that creates a simple set of rectangles.

From your command line::

qr --factory=svg-path "Some text" > test.svg
qr --factory=svg "Some text" > test.svg
qr --factory=svg-fragment "Some text" > test.svg

Or in Python:

.. code:: python

import qrcode
import qrcode.image.svg

if method == 'basic':
    # Simple factory, just a set of rects.
    factory = qrcode.image.svg.SvgImage
elif method == 'fragment':
    # Fragment factory (also just a set of rects)
    factory = qrcode.image.svg.SvgFragmentImage
else:
    # Combined path factory, fixes white space that may occur when zooming
    factory = qrcode.image.svg.SvgPathImage

img = qrcode.make('Some data here', image_factory=factory)

Two other related factories are available that work the same, but also fill the background of the SVG with white::

qrcode.image.svg.SvgFillImage
qrcode.image.svg.SvgPathFillImage

The QRCode.make_image() method forwards additional keyword arguments to the underlying ElementTree XML library. This helps to fine tune the root element of the resulting SVG:

.. code:: python

import qrcode
qr = qrcode.QRCode(image_factory=qrcode.image.svg.SvgPathImage)
qr.add_data('Some data')
qr.make(fit=True)

img = qr.make_image(attrib={'class': 'some-css-class'})

You can convert the SVG image into strings using the to_string() method. Additional keyword arguments are forwarded to ElementTrees tostring():

.. code:: python

img.to_string(encoding='unicode')

Pure Python PNG

If Pillow is not installed, the default image factory will be a pure Python PNG encoder that uses pypng.

You can use the factory explicitly from your command line::

qr --factory=png "Some text" > test.png

Or in Python:

.. code:: python

import qrcode
from qrcode.image.pure import PyPNGImage
img = qrcode.make('Some data here', image_factory=PyPNGImage)

Styled Image

Works only with versions_ >=7.2 (SVG styled images require 7.4).

.. _versions: https://github.com/lincolnloop/python-qrcode/blob/master/CHANGES.rst#72-19-july-2021

To apply styles to the QRCode, use the StyledPilImage or one of the standard SVG_ image factories. These accept an optional module_drawer parameter to control the shape of the QR Code.

These QR Codes are not guaranteed to work with all readers, so do some experimentation and set the error correction to high (especially if embedding an image).

Other PIL module drawers:

.. image:: doc/module_drawers.png

For SVGs, use SvgSquareDrawer, SvgCircleDrawer, SvgPathSquareDrawer, or SvgPathCircleDrawer.

These all accept a size_ratio argument which allows for "gapped" squares or circles by reducing this less than the default of Decimal(1).

The StyledPilImage additionally accepts an optional color_mask parameter to change the colors of the QR Code, and an optional embeded_image_path to embed an image in the center of the code.

Other color masks:

.. image:: doc/color_masks.png

Here is a code example to draw a QR code with rounded corners, radial gradient and an embedded image:

.. code:: python

import qrcode
from qrcode.image.styledpil import StyledPilImage
from qrcode.image.styles.moduledrawers.pil import RoundedModuleDrawer
from qrcode.image.styles.colormasks import RadialGradiantColorMask

qr = qrcode.QRCode(error_correction=qrcode.constants.ERROR_CORRECT_L)
qr.add_data('Some data')

img_1 = qr.make_image(image_factory=StyledPilImage, module_drawer=RoundedModuleDrawer())
img_2 = qr.make_image(image_factory=StyledPilImage, color_mask=RadialGradiantColorMask())
img_3 = qr.make_image(image_factory=StyledPilImage, embeded_image_path="/path/to/image.png")

Examples

Get the text content from print_ascii:

.. code:: python

import io
import qrcode
qr = qrcode.QRCode()
qr.add_data("Some text")
f = io.StringIO()
qr.print_ascii(out=f)
f.seek(0)
print(f.read())

The add_data method will append data to the current QR object. To add new data by replacing previous content in the same object, first use clear method:

.. code:: python

import qrcode
qr = qrcode.QRCode()
qr.add_data('Some data')
img = qr.make_image()
qr.clear()
qr.add_data('New data')
other_img = qr.make_image()

Pipe ascii output to text file in command line::

qr --ascii "Some data" > "test.txt"
cat test.txt

Alternative to piping output to file to avoid PowerShell issues::

# qr "Some data" > test.png
qr --output=test.png "Some data"

========== Change log

7.4.2 (6 February 2023)

  • Allow pypng factory to allow for saving to a string (like qr.save("some_file.png")) in addition to file-like objects.

7.4.1 (3 February 2023)

  • Fix bad over-optimization in v7.4 that broke large QR codes. Thanks to mattiasj-axis!

7.4 (1 February 2023)

  • Restructure the factory drawers, allowing different shapes in SVG image factories as well.

  • Add a --factory-drawer option to the qr console script.

  • Optimize the output for the SVGPathImage factory (more than 30% reduction in file sizes).

  • Add a pypng image factory as a pure Python PNG solution. If pillow is not installed, then this becomes the default factory.

  • The pymaging image factory has been removed, but its factory shortcut and the actual PymagingImage factory class now just link to the PyPNGImage factory.

7.3.1 (1 October 2021)

  • Improvements for embedded image.

7.3 (19 August 2021)

  • Skip color mask if QR is black and white

7.2 (19 July 2021)

  • Add Styled PIL image factory, allowing different color masks and shapes in QR codes

  • Small performance inprovement

  • Add check for border size parameter

7.1 (1 July 2021)

  • Add --ascii parameter to command line interface allowing to output ascii when stdout is piped

  • Add --output parameter to command line interface to specify output file

  • Accept RGB tuples in fill_color and back_color

  • Add to_string method to SVG images

  • Replace inline styles with SVG attributes to avoid CSP issues

  • Add Python3.10 to supported versions

7.0 (29 June 2021)

  • Drop Python < 3.6 support.

6.1 (14 January 2019)

  • Fix short chunks of data not being optimized to the correct mode.

  • Tests fixed for Python 3

6.0 (23 March 2018)

  • Fix optimize length being ignored in QRCode.add_data.

  • Better calculation of the best mask pattern and related optimizations. Big thanks to cryptogun!

5.3 (18 May 2016)

  • Fix incomplete block table for QR version 15. Thanks Rodrigo Queiro for the report and Jacob Welsh for the investigation and fix.

  • Avoid unnecessary dependency for non MS platforms, thanks to Noah Vesely.

  • Make BaseImage.get_image() actually work.

5.2 (25 Jan 2016)

  • Add --error-correction option to qr script.

  • Fix script piping to stdout in Python 3 and reading non-UTF-8 characters in Python 3.

  • Fix script piping in Windows.

  • Add some useful behind-the-curtain methods for tinkerers.

  • Fix terminal output when using Python 2.6

  • Fix terminal output to display correctly on MS command line.

5.2.1

  • Small fix to terminal output in Python 3 (and fix tests)

5.2.2

  • Revert some terminal changes from 5.2 that broke Python 3's real life tty code generation and introduce a better way from Jacob Welsh.

5.1 (22 Oct 2014)

  • Make qr script work in Windows. Thanks Ionel Cristian Mărieș

  • Fixed print_ascii function in Python 3.

  • Out-of-bounds code version numbers are handled more consistently with a ValueError.

  • Much better test coverage (now only officially supporting Python 2.6+)

5.0 (17 Jun 2014)

  • Speed optimizations.

  • Change the output when using the qr script to use ASCII rather than just colors, better using the terminal real estate.

  • Fix a bug in passing bytecode data directly when in Python 3.

  • Substation speed optimizations to best-fit algorithm (thanks Jacob Welsh!).

  • Introduce a print_ascii method and use it as the default for the qr script rather than print_tty.

5.0.1

  • Update version numbers correctly.

4.0 (4 Sep 2013)

  • Made qrcode work on Python 2.4 - Thanks tcely. Note: officially, qrcode only supports 2.5+.

  • Support pure-python PNG generation (via pymaging) for Python 2.6+ -- thanks Adam Wisniewski!

  • SVG image generation now supports alternate sizing (the default box size of 10 == 1mm per rectangle).

  • SVG path image generation allows cleaner SVG output by combining all QR rects into a single path. Thank you, Viktor Stískala.

  • Added some extra simple SVG factories that fill the background white.

4.0.1

  • Fix the pymaging backend not able to save the image to a buffer. Thanks ilj!

4.0.2

  • Fix incorrect regex causing a comma to be considered part of the alphanumeric set.

  • Switch to using setuptools for setup.py.

4.0.3

  • Fix bad QR code generation due to the regex comma fix in version 4.0.2.

4.0.4

  • Bad version number for previous hotfix release.

3.1 (12 Aug 2013)

  • Important fixes for incorrect matches of the alphanumeric encoding mode. Previously, the pattern would match if a single line was alphanumeric only (even if others wern't). Also, the two characters { and } had snuck in as valid characters. Thanks to Eran Tromer for the report and fix.

  • Optimized chunking -- if the parts of the data stream can be encoded more efficiently, the data will be split into chunks of the most efficient modes.

3.1.1

  • Update change log to contain version 3.1 changes. :P

  • Give the qr script an --optimize argument to control the chunk optimization setting.

3.0 (25 Jun 2013)

  • Python 3 support.

  • Add QRCode.get_matrix, an easy way to get the matrix array of a QR code including the border. Thanks Hugh Rawlinson.

  • Add in a workaround so that Python 2.6 users can use SVG generation (they must install lxml).

  • Some initial tests! And tox support (pip install tox) for testing across Python platforms.

2.7 (5 Mar 2013)

  • Fix incorrect termination padding.

2.6 (2 Apr 2013)

  • Fix the first four columns incorrectly shifted by one. Thanks to Josep Gómez-Suay for the report and fix.

  • Fix strings within 4 bits of the QR version limit being incorrectly terminated. Thanks to zhjie231 for the report.

2.5 (12 Mar 2013)

  • The PilImage wrapper is more transparent - you can use any methods or attributes available to the underlying PIL Image instance.

  • Fixed the first column of the QR Code coming up empty! Thanks to BecoKo.

2.5.1

  • Fix installation error on Windows.

2.4 (23 Apr 2012)

  • Use a pluggable backend system for generating images, thanks to Branko Čibej! Comes with PIL and SVG backends built in.

2.4.1

  • Fix a packaging issue

2.4.2

  • Added a show method to the PIL image wrapper so the run_example function actually works.

2.3 (29 Jan 2012)

  • When adding data, auto-select the more efficient encoding methods for numbers and alphanumeric data (KANJI still not supported).

2.3.1

  • Encode unicode to utf-8 bytestrings when adding data to a QRCode.

2.2 (18 Jan 2012)

  • Fixed tty output to work on both white and black backgrounds.

  • Added border parameter to allow customizing of the number of boxes used to create the border of the QR code

2.1 (17 Jan 2012)

  • Added a qr script which can be used to output a qr code to the tty using background colors, or to a file via a pipe.