Introduction¶

A non-hardware dependant miniature QR generator library. All native Python!

Dependencies¶

This driver depends on:

Adafruit CircuitPython

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle.

Usage Example¶

import adafruit_miniqr

qr = adafruit_miniqr.QRCode()
qr.add_data(b'https://www.adafruit.com')
qr.make()
print(qr.matrix)

Contributing¶

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.

Building locally¶

Zip release files¶

To build this library locally you’ll need to install the circuitpython-build-tools package.

python3 -m venv .env
source .env/bin/activate
pip install circuitpython-build-tools

Once installed, make sure you are in the virtual environment:

source .env/bin/activate

Then run the build:

circuitpython-build-bundles --filename_prefix adafruit-circuitpython-miniqr --library_location .

Sphinx documentation¶

Sphinx is used to build the documentation based on rST files and comments in the code. First, install dependencies (feel free to reuse the virtual environment from above):

python3 -m venv .env
source .env/bin/activate
pip install Sphinx sphinx-rtd-theme

Now, once you have the virtual environment activated:

cd docs
sphinx-build -E -W -b html . _build/html

This will output the documentation to docs/_build/html. Open the index.html in your browser to view them. It will also (due to -W) error out on any warning like Travis will. This is a good way to locally verify it will pass.

Table of Contents¶

Simple test¶

Ensure your device works with this simple test.

examples/miniqr_simpletest.py¶

import sys
import adafruit_miniqr

# For drawing filled rectangles to the console:
out = sys.stdout
WHITE = "\x1b[1;47m  \x1b[40m"
BLACK = "  "

def prettyprint_QR(matrix):
    # white 4-pixel border at top
    for _ in range(4):
        for _ in range(matrix.width+8):
            out.write(WHITE)
        print()
    for y in range(matrix.height):
        out.write(WHITE*4)   # 4-pixel border to left
        for x in range(matrix.width):
            if matrix[x, y]:
                out.write(BLACK)
            else:
                out.write(WHITE)
        out.write(WHITE*4)   # 4-pixel bporder to right
        print()
    # white 4-pixel border at bottom
    for _ in range(4):
        for _ in range(matrix.width+8):
            out.write(WHITE)
        print()

qr = adafruit_miniqr.QRCode(qr_type=3, error_correct=adafruit_miniqr.L)
qr.add_data(b'https://www.adafruit.com')
qr.make()
print(qr.matrix)
prettyprint_QR(qr.matrix)

`adafruit_miniqr`¶

A non-hardware dependant miniature QR generator library. All native Python!

Author(s): ladyada

Implementation Notes¶

Hardware:

Any!

Software and Dependencies:

Python 3

class adafruit_miniqr.QRBitBuffer¶

Storage class for a length of individual bits

get(index)¶: The bit value at a location

get_length_bits()¶: Size of bit buffer

put(num, length)¶: Add a number of bits from a single integer value

put_bit(bit)¶: Insert one bit at the end of the bit buffer

class adafruit_miniqr.QRBitMatrix(width, height)¶: A bit-packed storage class for matrices

class adafruit_miniqr.QRCode(*, qr_type=None, error_correct=1)¶

The generator class for QR code matrices

add_data(data)¶: Add more data to the QR code, must be bytestring stype

make(*, test=False, mask_pattern=0)¶: Perform the actual generation of the QR matrix. To keep things small and speedy we don’t generate all 8 mask patterns and pick the best. Instead, please pass in a desired mask_pattern, the default mask is 0.

class adafruit_miniqr.QRPolynomial(num, shift)¶

Structure for creating and manipulating error code polynomials

get(index)¶: The exponent at the index location

get_length()¶: Length of the poly

multiply(e)¶: Multiply two polynomials, returns a new one

class adafruit_miniqr.QRUtil¶

A selection of bit manipulation tools for QR generation and BCH encoding

static get_BCH_digit(data)¶: Count digits in data

static get_BCH_type_info(data)¶: Encode with G15 BCH mask

static get_BCH_type_number(data)¶: Encode with G18 BCH mask

static get_error_correct_polynomial(ecc_length)¶: Generate a ecc polynomial

static get_mask(mask, i, j)¶: Perform matching calculation on two vals for given pattern mask

static get_pattern_position(qr_type)¶: The mask pattern position array for this QR type