Create a QR code for FREE using R

R is a very versatile programming language and can do many graphical tasks with ease. Here, I demonstrate how to use R to generate QRcodes. These codes are useful for sharing hyperlinks in presentation slides, posters and flyers.

The qrcode R package can do exactly that. The documentation can be found on GitHub here.

The package can be installed from the CRAN package manager in the standard way:

install.packages("qrcode")

Once it is installed, load the package using the library command:

library(qrcode)

Now you can give it some data to make a QR code. Here I'm using this blog's URL.

code <- qr_code("https://genomespot.blogspot.com")

Next, you can output the code graphically. The print() command will print it in the terminal which is a bit ugly. The plot() command will pop up a window with the code.

print(code)

plot(code)

Basic QRcode for GenomeSpot Blog

Now this generates a simple black and white QR code which might be sufficient for you. You can just grab a screenshot and paste it where you need it. However I would recommend that you also save a SVG file of the QR code which will retain the high resolution unlike a standard screenshot.

This also gives you the ability to tweak the colours to suit your application.

generate_svg(code,filename ="myqrcode.svg", foreground = "green", background = "gold")

QRcode for GenomeSpot in green and yellow


This package also allows you to include a logo in the QR code, which is normally a feature that requires a paid subscription. Here you can do it for free in R.

First generate the QR code as per normal, except specify ecl="H" which specifies a high error correction level.

code2 <- qr_code("https://genomespot.blogspot.com", ecl="H")

Next, add the logo from a source SVG file, specifying a lower error correction level.

code2 <- add_logo(code2,logo="thumbs-up-svgrepo-com.svg",ecl="L")

Then finally generate the QCcode with the logo

generate_svg(code2,filename ="myqrcode.svg", foreground = "orange", background = "white")

Have fun!

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