Python ctypes interface for QR code decoding library libquirc.

Run tests with a python setup.py test command or look for Travis build logs.

API stability isn't guaranteed before 1.0.0 version. Versioning is propagated by semver.org.

When version 1.0.0 will be released the API will be frozen, and any changes which aren't backwards compatible will force a major version bump.

Just call a quirc.decode() function with a PIL.Image object as a parameter, like this:

import Image

image = Image.open('tests/images/test1.png')
for code in quirc.decode(image):
    print code['text']
    # >>> test1

Currently only PIL is supported.

Low-level API directly corresponds to the C API:

Create new Quirc object with a quirc.api.new function.

qr = quirc.api.new()

Set the image size that you'll be working with

quirc.api.resize(qr, 640, 480)

Processing frames is done in two stages. The first stage is an image-recognition stage called identification, which takes a grayscale image and searches for QR codes.

buffer = quirc.api.begin(qr, 640, 480)

Now fill out this image buffer with a pixels. One byte per pixel, w pixels per line, h lines in the buffer. Here is a simplest example from the tests/test_quirc.py:test_fill:

for idx, pixel in enumerate(pixels):
    buffer[idx] = ctypes.c_uint8(ord(pixel))

After the call to quirc.api.end, the decoder holds a list of detected QR codes

quirc.api.end(qr)

At this point, the second stage of processing occurs - decoding.

Number of QR codes identified in this image

num_codes = quirc.api.count(obj)

Iterate all over the identified codes

for i in range(num_codes):
    # Prepare required structures for data filling

    # `quirc.api.structures.Code` structure contains information about detected QR code in the input image
    code = quirc.api.structures.Code()
    quirc.api.extract(qr, i, ctypes.byref(code))

    # `quirc.api.structures.Data` holds the decoded QR code data
    data = quirc.api.structures.Data()
    quirc.api.decode(ctypes.byref(code), ctypes.byref(data))

    # Extracting QR-encoded string now
    print ctypes.string_at(data.payload, data.payload_len)

Finally, release the allocated memory

quirc.api.destroy(qr)

If library raises an exception OSError: libquirc.so.1: cannot open shared object file: No such file or directory, set environment variable LD_PRELOAD_PATH to /usr/local/lib/ like this: $ LD_PRELOAD_PATH=/usr/local/lib/ ./myscript.py

If you want to contribute, follow the pep8 guideline, and include the tests.