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

Project address

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

Import statement

import qrcode

QRCode class usage

Instantiate a QRCode object with the desired configuration:

qr = 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 yields a 21×21 matrix; None or fit=True lets the library choose the smallest size automatically.

error_correction : Sets error‑correction level.

ERROR_CORRECT_L – ~7% error correction.

ERROR_CORRECT_M – default, ~15%.

ERROR_CORRECT_Q – ~25%.

ERROR_CORRECT_H – ~30%.

box_size : Pixel size of each QR module (default 10).

border : Width of the white border in modules (default 4).

image_factory : Chooses the image backend (default is PIL).

mask_pattern : Selects the mask pattern for the QR code.

Common methods

add_data(data, optimize=20)

: Add text to be encoded; optimize splits data into chunks for a more compact QR code. make(fit=True): Automatically selects the smallest version that fits the data; also chooses an optimal mask.

make_image(fill_color=None, back_color=None, image_factory=None)

: Returns an image object (PIL by default). Set fill_color and back_color for colored QR codes. clear(): Clears the stored data. get_matrix(): Returns the QR code matrix as a list of lists. print_ascii(out=None, tty=False, invert=False): Prints an ASCII representation (mostly for debugging).

SVG image generation

The library can produce three SVG variants via image_factory: SvgPathImage: Vector paths – scalable without quality loss. SvgImage: Collection of rectangles forming a complete SVG file (may show gaps when zoomed). SvgFragmentImage: Rectangle collection suitable as an SVG fragment.

import qrcode.image.svg
if method == 'basic':
    factory = qrcode.image.svg.SvgImage
elif method == 'fragment':
    factory = qrcode.image.svg.SvgFragmentImage
else:
    factory = qrcode.image.svg.SvgPathImage
img = qrcode.make('Some data here', image_factory=factory)

PNG image generation

To use the optional pymaging backend, install it via:

pip install git+https://github.com/ojii/pymaging.git#egg=pymaging
pip install git+https://github.com/ojii/pymaging-png.git#egg=pymaging-png

Then pass qrcode.image.pure.PymagingImage as image_factory:

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

In most cases the default PIL backend is sufficient:

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