R/square.R

In tpq/glitchr: Make GLitcharrrrRt

#' Square Image
#'
#' If an image is not square, add white space to make it square.
#'
#' @param img An image with any number of color channels.
#'
#' @export
square <- function(img){

  # Change 2D images into 3D images
  if(length(dim(img)) == 2){

    dim(img) <- c(dim(img)[1], dim(img)[2], 1)
  }

  if(dim(img)[2] < dim(img)[1]){ # If image is a portrait

    # Create white space for sides
    filler.dim <- round((nrow(img) - ncol(img))/2, 0)
    filler <- matrix(1, nrow(img), filler.dim)

    # Create container for output
    newimg <- array(0, dim = c(nrow(img), ncol(img) + 2 * filler.dim, dim(img)[3]))
    for(i in 1:dim(img)[3]){ # For each color channel

      # Add white space to image
      newimg[,,i] <- do.call(cbind, list(filler, img[,,i], filler))
    }

  }else if(dim(img)[2] > dim(img)[1]){ # If image is a landscape

    # Create white space for sides
    filler.dim <- round((ncol(img) - nrow(img))/2, 0)
    filler <- matrix(1, filler.dim, ncol(img))

    # Create container for output
    newimg <- array(0, dim = c(nrow(img) + 2 * filler.dim, ncol(img), dim(img)[3]))
    for(i in 1:dim(img)[3]){ # For each color channel

      # Add white space to image
      newimg[,,i] <- do.call(rbind, list(filler, img[,,i], filler))
    }
  }

  return(newimg)
}

#' Square Image
#'
#' If an image is not square, add white space to make it square.
#'
#' @param dir A directory of *[jJ][pP][eE]?[gG] files.
#'
#' @export
squaregram <- function(dir = getwd()){

  oldwd <- getwd()
  setwd(dir)
  files <- list.files(pattern = "*[jJ][pP][eE]?[gG]")
  dir.create("square", showWarnings = FALSE)

  for(file in files){ # For each file in directory

    numTicks <- progress(which(file == files), length(files), numTicks)
    img <- jpeg::readJPEG(file)
    newimg <- square(img)
    jpeg::writeJPEG(newimg, paste0("square/", file))
  }

  setwd(oldwd)
}