qrcode-rust

QR code and Micro QR code encoder in Rust. Documentation.

Cargo.toml

[dependencies]
qrcode = "0.14.1"

The default settings will depend on the image crate. If you don't need image generation capability, disable the default-features:

[dependencies]
qrcode = { version = "0.14.1", default-features = false, features = ["std"] }

Example

Image generation

use qrcode::QrCode;
use image::Luma;

fn main() {
    // Encode some data into bits.
    let code = QrCode::new(b"01234567").unwrap();

    // Render the bits into an image.
    let image = code.render::<Luma<u8>>().build();

    // Save the image.
    image.save("/tmp/qrcode.png").unwrap();
}

Generates this image:

String generation

use qrcode::QrCode;

fn main() {
    let code = QrCode::new(b"Hello").unwrap();
    let string = code.render::<char>()
        .dark_color('#')
        .quiet_zone(false)
        .module_dimensions(2, 1)
        .build();
    println!("{string}");
}

Generates this output:

##############    ########  ##############
##          ##          ##  ##          ##
##  ######  ##  ##  ##  ##  ##  ######  ##
##  ######  ##  ##  ##      ##  ######  ##
##  ######  ##  ####    ##  ##  ######  ##
##          ##  ####  ##    ##          ##
##############  ##  ##  ##  ##############
                ##  ##
##  ##########    ##  ##    ##########
      ##        ##    ########    ####  ##
    ##########    ####  ##  ####  ######
    ##    ##  ####  ##########    ####
  ######    ##########  ##    ##        ##
                ##      ##    ##  ##
##############    ##  ##  ##    ##  ####
##          ##  ##  ##        ##########
##  ######  ##  ##    ##  ##    ##    ##
##  ######  ##  ####  ##########  ##
##  ######  ##  ####    ##  ####    ##
##          ##    ##  ########  ######
##############  ####    ##      ##    ##

SVG generation

use qrcode::{QrCode, Version, EcLevel};
use qrcode::render::svg;

fn main() {
    let code = QrCode::with_version(b"01234567", Version::Micro(2), EcLevel::L).unwrap();
    let image = code.render()
        .min_dimensions(200, 200)
        .dark_color(svg::Color("#800000"))
        .light_color(svg::Color("#ffff80"))
        .build();
    println!("{image}");
}

Generates this SVG:

Unicode string generation

use qrcode::QrCode;
use qrcode::render::unicode;

fn main() {
    let code = QrCode::new("mow mow").unwrap();
    let image = code.render::<unicode::Dense1x2>()
        .dark_color(unicode::Dense1x2::Light)
        .light_color(unicode::Dense1x2::Dark)
        .build();
    println!("{image}");
}

Generates this output:

█████████████████████████████
█████████████████████████████
████ ▄▄▄▄▄ █ ▀▀▀▄█ ▄▄▄▄▄ ████
████ █   █ █▀ ▀ ▀█ █   █ ████
████ █▄▄▄█ ██▄  ▀█ █▄▄▄█ ████
████▄▄▄▄▄▄▄█ ▀▄▀ █▄▄▄▄▄▄▄████
████▄▀ ▄▀ ▄ █▄█  ▀ ▀█ █▄ ████
████▄██▄▄▀▄▄▀█▄ ██▀▀█▀▄▄▄████
█████▄▄▄█▄▄█  ▀▀▄█▀▀▀▄█▄▄████
████ ▄▄▄▄▄ █   ▄▄██▄ ▄ ▀▀████
████ █   █ █▀▄▄▀▄▄ ▄▄▄▄ ▄████
████ █▄▄▄█ █▄  █▄▀▄▀██▄█▀████
████▄▄▄▄▄▄▄█▄████▄█▄██▄██████
█████████████████████████████
▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀

PIC generation

use qrcode::render::pic;
use qrcode::QrCode;

fn main() {
    let code = QrCode::new(b"01234567").unwrap();
    let image = code
        .render::<pic::Color>()
        .min_dimensions(1, 1)
        .build();
    println!("{image}");
}

Generates PIC output that renders as follows:

maxpswid=29;maxpsht=29;movewid=0;moveht=1;boxwid=1;boxht=1
define p { box wid $3 ht $4 fill 1 thickness 0.1 with .nw at $1,-$2 }
box wid maxpswid ht maxpsht with .nw at 0,0
p(4,4,1,1)
p(5,4,1,1)
p(6,4,1,1)
p(7,4,1,1)
p(8,4,1,1)
p(9,4,1,1)
…

See test_annex_i_micro_qr_as_pic.pic for a full example.

EPS generation

use qrcode::render::eps;
use qrcode::{EcLevel, QrCode, Version};

fn main() {
    let code = QrCode::with_version(b"01234567", Version::Micro(2), EcLevel::L).unwrap();
    let image = code
        .render()
        .min_dimensions(200, 200)
        .dark_color(eps::Color([0.5, 0.0, 0.0]))
        .light_color(eps::Color([1.0, 1.0, 0.5]))
        .build();
    println!("{image}");
}

Generates EPS output that renders as follows:

%!PS-Adobe-3.0 EPSF-3.0
%%BoundingBox: 0 0 204 204
%%Pages: 1
%%EndComments
gsave
1 1 0.5 setrgbcolor
0 0 204 204 rectfill
grestore
0.5 0 0 setrgbcolor
24 180 12 12 rectfill
36 180 12 12 rectfill
48 180 12 12 rectfill
60 180 12 12 rectfill
72 180 12 12 rectfill
84 180 12 12 rectfill
…

See test_annex_i_micro_qr_as_eps.eps for a full example.