Polyconseil/zbarlight

ZbarLight

zbarlight is a simple wrapper for the zbar library. For now, it can read all zbar supported codes. Contributions, suggestions and pull requests are welcome.

zbarlight is hosted on Github at <https://github.com/Polyconseil/zbarlight/>.

Installation

You need to install ZBar Bar Code Reader <http://zbar.sourceforge.net/> and its headers before installing zbarlight.

On Debian

$ apt-get install libzbar0 libzbar-dev
$ pip install zbarlight  # you can also use setuptools directly

On Mac OS X

$ brew install zbar
$ export LDFLAGS="-L$(brew --prefix zbar)/lib"
$ export CFLAGS="-I$(brew --prefix zbar)/include"
$ pip install zbarlight

On Windows

Instruction can be found on <https://gist.github.com/Zephor5/aea563808d80f488310869b69661f330>.

How To use ZbarLight

from PIL import Image
import zbarlight

file_path = './tests/fixtures/two_qr_codes.png'
with open(file_path, 'rb') as image_file:
    image = Image.open(image_file)
    image.load()

codes = zbarlight.scan_codes(['qrcode'], image)
print('QR codes: %s' % codes)

Troubleshooting

In some case zbarlight will not be able to detect the 1D or 2D code in an image, one of the known cause is that the image background color is the same as the foreground color after conversion to grey scale (it's happen on images with alpha channel). You can use the copy_image_on_background function to add a background color on your image.

from PIL import Image
import zbarlight

file_path = './tests/fixtures/two_qr_codes.png'
with open(file_path, 'rb') as image_file:
    image = Image.open(image_file)
    image.load()

new_image = zbarlight.copy_image_on_background(image, color=zbarlight.WHITE)  # <<<<<<<<<<<<<<<< Add this line <<<<
codes = zbarlight.scan_codes(['qrcode'], new_image)
print('QR codes: %s' % codes)

Some other cases without known solutions are show in the scan_codes() tests (search for the expected failures). Any clues on these cases is welcome.