Master Python QR Code Generation: Parameters, Methods, and Image Formats

Project URL

https://github.com/lincolnloop/python-qrcode

Import

import qrcode

Usage

QRCode constructor

qrcode.QRCode(version=1, error_correction=qrcode.ERROR_CORRECT_L, box_size=10, border=4, image_factory=None, mask_pattern=None)

Parameter explanations

version: controls QR code size (1‑40). Version 1 produces a 21×21 matrix; None or fit=True lets the library choose the optimal size.

error_correction: sets error‑correction level (L≈7%, M≈15%, Q≈25%, H≈30%).

box_size: pixel size of each matrix module, default 10.

border: number of modules for the quiet zone around the QR code, default 4.

image_factory: selects the image backend, default is a PIL image.

mask_pattern: chooses a mask pattern for the QR code.

Common methods

add_data(data, optimize=20): adds text to be encoded; set optimize=0 to disable optimization.

make(fit=True): automatically selects the smallest version and mask that fit the data.

make_image(fill_color=None, back_color=None, image_factory=None): creates and returns an image (default PIL).

clear(): clears the stored data.

get_matrix(): returns the QR code matrix.

print_ascii(out=None, tty=False, invert=False): prints an ASCII representation of the QR code.

SVG output

The library can generate three SVG variants: a path‑based vector SVG, a rectangle‑based full SVG, and a rectangle‑based SVG fragment. These correspond to the classes SvgPathImage, SvgImage, and SvgFragmentImage in svg.py. Pass the desired class as image_factory when creating a QRCode or calling qrcode.make.

import qrcode.image.svg as svg
factory = svg.SvgImage  # or svg.SvgPathImage, svg.SvgFragmentImage
img = qrcode.make('Some data here', image_factory=factory)

PNG output

For PNG generation you can use the optional Pymaging backend. Install it via pip and use PymagingImage as the image factory. The default PIL backend works for most cases.

pip install git+https://github.com/ojii/pymaging.git#egg=pymaging
pip install git+https://github.com/ojii/pymaging-png.git#egg=pymaging-png
from qrcode.image.pure import PymagingImage
img = qrcode.make('Some data here', image_factory=PymagingImage)

Simple make usage

# Display the QR code
qrcode.make('hello world!').show()
# Save as PNG
qrcode.make('hello world!').save('hello.png')