###开源项目
python-qrcode
###install
安装Pillow
安装 python-qrcode
###Usage
From the command line, use the installed qr
script::
qr "Some text" > test.png
Or in Python, use the make
shortcut function::
import qrcode
img = qrcode.make('Some data here')
Advanced Usage
For more control, use the QRCode
class. For example::
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()
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.
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
On Python 2.6 must install lxml since the older xml.etree.ElementTree version
can not be used to create SVG images.
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::
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
Pure Python PNG
Install the following two packages::
pip install git+git://github.com/ojii/pymaging.git#egg=pymaging
pip install git+git://github.com/ojii/pymaging-png.git#egg=pymaging-png
From your command line::
qr --factory=pymaging "Some text" > test.png
Or in Python::
import qrcode
from qrcode.image.pure import PymagingImage
img = qrcode.make('Some data here', image_factory=PymagingImage)