The OpenImageR package is an image processing library. It includes functions for image preprocessing, filtering and image recognition. More details on the functionality of OpenImageR can be found in the Vignettes and in the package Documentation.
UPDATE 06-11-2018
As of version 1.1.2 the OpenImageR package allows R package maintainers to perform linking between packages at a C++ code (Rcpp) level. This means that the Rcpp functions of the OpenImageR package can be called in the C++ files of another package. In the next lines I’ll give detailed explanations on how this can be done:
Assumming that an R package (‘PackageA’) calls one of the OpenImageR Rcpp functions. Then the maintainer of ‘PackageA’ has to :
or download the latest version from Github using the devtools package,
# include <RcppArmadillo.h>
# include <OpenImageRheader.h>
// [[Rcpp::depends("RcppArmadillo")]]
// [[Rcpp::depends(OpenImageR)]]
// [[Rcpp::plugins(cpp11)]]
The available C++ classes (Utility_functions, Gabor_Features, Gabor_Features_Rcpp, HoG_features, Image_Hashing) can be found in the inst/include/OpenImageRheader.h file.
A complete minimal example would be :
# include <RcppArmadillo.h>
# include <OpenImageRheader.h>
// [[Rcpp::depends("RcppArmadillo")]]
// [[Rcpp::depends(OpenImageR)]]
// [[Rcpp::plugins(cpp11)]]
// [[Rcpp::export]]
arma::mat rgb_2gray(arma::cube RGB_image) {
oimageR::Utility_functions UTLF;
return UTLF.rgb_2gray(RGB_image);
}
Then, by opening an R file a user can call the rgb_2gray function using,
Rcpp::sourceCpp('example.cpp') # assuming that the previous Rcpp code is included in 'example.cpp'
set.seed(1)
im_rgb = array(runif(30000), c(100, 100, 3))
im_grey = rgb_2gray(im_rgb)
str(im_grey)Use the following link to report bugs/issues,