teoria / qrencoder

:white_square_button: Make QR codes in R via libqrencode

qrencoder uses libqrencode to make QR codes in R

NOTE: there now exists a package on CRAN -- qrcode -- that does not require a C/C++ library. I have no intention of submitting this to CRAN anytime soon.

I have no idea why you would want to, but this was to help answer a question (actually, two questions - who knew QR codes were so popular?) on StackOverflow.

The following functions are implemented:

• qrencode: Return a QR encoded string as a matrix
• qrencode_df: Return a QR encoded string as an x, y, z data.frame
• qrencode_png: Return a QR encoded string as a base 64 encoded inline png
• qrencode_raster: Return a QR encoded string as a raster object

NOTE: You'll need Rcpp, base64enc, raster & png installed (and, libqrencode of course).

NOTE: Not tested under Windows.

News

• Version 0.0.1.9000 : made raster a Depends vs Imports
• Version 0.0.0.9000 released

Installation

devtools::install_github("hrbrmstr/qrencoder")

Usage

library(qrencoder)
#> Loading required package: raster
#> Loading required package: sp

# current verison
packageVersion("qrencoder")
#> [1] '0.0.1.9000'

url <- "http://rud.is/b"
head(qrencode(url))
#>      [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13] [,14] [,15] [,16] [,17] [,18] [,19] [,20]
#> [1,]    1    1    1    1    1    1    1    0    1     0     0     0     0     0     1     1     1     1     1     1
#> [2,]    1    0    0    0    0    0    1    0    1     1     1     1     0     0     1     0     0     0     0     0
#> [3,]    1    0    1    1    1    0    1    0    0     0     1     1     1     0     1     0     1     1     1     0
#> [4,]    1    0    1    1    1    0    1    0    1     0     1     1     0     0     1     0     1     1     1     0
#> [5,]    1    0    1    1    1    0    1    0    0     1     1     0     1     0     1     0     1     1     1     0
#> [6,]    1    0    0    0    0    0    1    0    0     0     1     0     0     0     1     0     0     0     0     0
#>      [,21]
#> [1,]     1
#> [2,]     1
#> [3,]     1
#> [4,]     1
#> [5,]     1
#> [6,]     1

head(qrencode_df(url))
#>   x  y z
#> 1 0 20 1
#> 2 1 20 1
#> 3 2 20 1
#> 4 3 20 1
#> 5 4 20 1
#> 6 5 20 1

qrencode_png(url)
#> [1] "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABUAAAAVCAAAAACMfPpKAAAACXBIWXMAAC4jAAAuIwF4pT92AAAAfElEQVQYlU2QWwrEMAwDR0vuf+XZj8qJSyjIyNYjAkAMQNFhkBCKzoNiin70kxKBN41ENuf7+9AZWQOGRx/2m4TeKy2YO0GyDpwszW5EUCs/ur78NZtGvSa8azdPDGttsonot8LtDFNnrs4yLSbuJk0ajnV3vevhCxUj4Q+R11n764g4WgAAAABJRU5ErkJggg=="

qrencode_raster(url)
#> class       : RasterLayer 
#> dimensions  : 21, 21, 441  (nrow, ncol, ncell)
#> resolution  : 0.04761905, 0.04761905  (x, y)
#> extent      : 0, 1, 0, 1  (xmin, xmax, ymin, ymax)
#> coord. ref. : NA 
#> data source : in memory
#> names       : layer 
#> values      : 0, 1  (min, max)

par(mar=c(0,0,0,0))
image(qrencode_raster("http://rud.is/b"), 
      asp=1, col=c("white", "black"), axes=FALSE, 
      xlab="", ylab="")

Test Results

library(qrencoder)
library(testthat)

date()
#> [1] "Mon Aug 24 07:38:04 2015"

test_dir("tests/")
#> testthat results ========================================================================================================
#> OK: 0 SKIPPED: 0 FAILED: 0
#> 
#> DONE

Code of Conduct

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.