=============================
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)
6.0 (23 March 2018)
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
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
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
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)
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.