compress_images: Minify size your images

In ardata-fr/minimage: An R Interface to the 'compress-images' Software

Description

Minify size of images located in a directory and output results in another directory.

You will be able to use this function only if

• the program 'node.js' is installed on your machine,

• the command compress_images_install() has been executed once on your machine (it installs a set of "npm" packages).

Usage

compress_images(
  input,
  output = NULL,
  verbose = TRUE,
  overwrite = FALSE,
  jpg_quality = "75",
  png_quality = "20-50",
  gif_colors = "64"
)

Arguments

input, output	input and output directories
verbose	should a log be printed in the console, default to TRUE.
overwrite	logical; should existing destination files be overwritten?
jpg_quality	Scale quantization tables to adjust image quality. Quality is "0" (worst) to "100" (best); default is "75".
png_quality	defined as "min-max", instructs pngquant to use the least amount of colors required to meet or exceed the max quality. If conversion results in quality below the min quality the image won't be saved.
gif_colors	Reduce the number of distinct colors in each output GIF to gif_colors or less. It must be between 2 and 256. This can be used to shrink output GIFs or eliminate any local color tables.

Value

a data.frame with details about input files and compressed files.

Examples

library(minimage)
library(locatexec)

was_avail <- compress_images_available()

if(exec_available("node") && exec_available("npm")){

  if(!was_avail)
    compress_images_install(force = TRUE)

  # generate dest folder
  new_dir <- tempfile()
  dir.create(new_dir)

  # run compression
  z <- compress_images(system.file(package = "minimage", "test-files"), new_dir)

  print(z)

  if(!was_avail)
    compress_images_uninstall()

}

ardata-fr/minimage documentation built on Aug. 24, 2021, 2:21 a.m.