QRCodeEx

Simple QR Code Generator written in Elixir with no other dependencies.

This project is a fork and a successor of SiliconJungles/eqrcode. It adds the following functionallity:

• more error coreection levels: :m, :q, :h (before was only :l)
• more QR code versions: 8..40 (before was only 1-7)

We tried to keep the project api compatible with SiliconJungles/eqrcode.

Installation

def deps do
  [
    {:qrcode_ex, "~> 0.1.0"}
  ]
end

Using QRCodeEx (Basic Usage)

You can use QRCodeEx to generate QR Code in SVG or PNG format.

qr_code_content = "your_qr_code_content"

# To SVG
qr_code_content
|> QRCodeEx.encode()
|> QRCodeEx.svg()

# To PNG
qr_code_content
|> QRCodeEx.encode()
|> QRCodeEx.png()

Note that the PNG format is only the binary. You still have to write the data to a file:

qr_code_png =
  qr_code_content
  |> QRCodeEx.encode()
  |> QRCodeEx.png()

File.write("path/where/you/want/to/save.png", qr_code_png, [:binary])

You should be able to see the file generated in the path you specified.

Image Rendering Options

SVG

You can pass in options into QRCodeEx.svg():

qr_code_content
|> QRCodeEx.encode()
|> QRCodeEx.svg(color: "#03B6AD", shape: "circle", width: 300, background_color: "#FFF")

You can specify the following attributes of the QR code:

• color: In hexadecimal format. The default is #000
• background_color: In hexadecimal format or :transparent. The default is #FFF.
• shape: Only square or circle. The default is square
• width: The width of the QR code in pixel. Without the width attribute, the QR code size will be dynamically generated based on the input string.
• viewbox: When set to true, the SVG element will specify its height and width using viewBox, instead of explicit height and width tags.

Default options are [color: "#000", shape: "square", background_color: "#FFF"].

PNG

You can specify the following attributes of the QR code:

• color: In binary format in the RGB order. The default is <<0, 0, 0>>
• background_color: In binary format or :transparent. The default is <<255, 255, 255>>
• width: The width of the QR code in pixel. (the actual size may vary, due to the number of modules in the code)

By default, QR code size will be dynamically generated based on the input string.

ASCII

You can also render the QRCode in your console:

qr_code_content
|> QRCodeEx.encode()
|> QRCodeEx.render()

Credits

• We reused most of the code from SiliconJungles/eqrcode to generate QR Codes up to version 7 and an error correction level of l.

• SiliconJungles/eqrcode reused most of the code from sunboshan/qrcode to generate the matrix required to render the QR Code. We also reference rqrcode on how to generate SVG from the QR Code matrix.

License

This project is Licensed under the MIT License.