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=============================
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
=====================
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