The qr-imager package

[ Tags: bsd3, data, library ] [ Propose Tags ]

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Dependencies aeson, base (>=4.8 && <5), bytestring, cryptonite, directory, either (<5), haskell-qrencode, jose-jwt, JuicyPixels, microlens, optparse-applicative, process, split, vector [details]
License BSD3
Copyright Copyright: (c) 2016 Vanessa McHale
Author Vanessa McHale
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Source repo head: git clone
Uploaded Sat Feb 3 23:42:05 UTC 2018 by vmchale
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Downloads 3275 total (129 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2018-02-04 [all 1 reports]
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Readme for qr-imager-

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QR Imager Library

Build Status

This is a library to generate .png files from QR codes.


The library depends on the C library libqrencode which you will need to install separately, as well as the C library Zbar from here. You should also be able to get them from your distro.


The library can be used via the exported functions createQRCode, byteStringToQR and readQRString, plus their signed counterparts. The first two export to ".png" while the third can be used on any image format Zbar supports.

The functions bsToImg and objToImg output JuicyPixels images for your further manipulation.



For building haskell, the best tool is currently Install it, and then type

stack install --install-ghc

in the appropriate directory, and it will be installed to your path.


Compiling will generate an executable called qrpipe which reads from stdin and outputs a file as the second argument, e.g.

echo 'My name is: Vanessa" | qrpipe write -v "nametag.png"

To then read the nametag:

qrpipe read "nametag.png"