Ruby script to create iOS application icon sets from PDF files. Requires ImageMagick and GhostScript.

create-icons

#!/usr/bin/env ruby
# Requires ImageMagick: http://www.imagemagick.org/
# Requires GhostScript: http://www.ghostscript.com/

require 'fileutils'

if ARGV.count < 2 then
  puts "Usage: #{File.basename(__FILE__)} <pdf-file> [<pdf-file> ...] <project-folder>"
  exit 1
end

pdf_files = []

(0..(ARGV.count - 2)).each do |i|
  pdf_file = ARGV[i]

  if File.extname(pdf_file) != ".pdf" then
    puts "File #{pdf_file} does not have a '.pdf' extension"
    exit 1
  end

  if !File.exists?(pdf_file) then
    puts "error: Could not find PDF file #{pdf_file}"
    exit 1
  end

  pdf_files.push(pdf_file)
end

proj_dir = File.join(ARGV[ARGV.count - 1])

if !Dir.exists?(proj_dir) then
  puts "error: Could not find project directory #{proj_dir}"
  exit 1
end

assets_dir = File.join(proj_dir, "Assets.xcassets")

if !Dir.exists?(assets_dir) then
  puts "error: Could not find directory #{assets_dir} in the project directory"
  exit 1
end

if `command -v convert` == '' then
  puts "error: Executable 'convert' not found in path. Please install ImageMagick."
end

if `command -v gs` == '' then
  puts "error: Executable 'gs' not found in path. Please install GhostScript."
end

pdf_files.each do |pdf_file|
  icon_set_dir = File.join(assets_dir, File.basename(pdf_file, ".pdf")) + ".appiconset"
  FileUtils.rm_rf icon_set_dir
  FileUtils.mkdir icon_set_dir

  puts "Creating icons from #{pdf_file} into #{icon_set_dir}"

  [20, 29, 40, 58, 76, 80, 87, 120, 152, 167, 180].each do |size|
    puts "Creating #{size}px icon"
    `convert -density 400 #{pdf_file} -scale #{size}x#{size} #{icon_set_dir}/appicon_#{size}.png`
  end

  contents_json = %q({
  "images":[
    { "size":"20x20", "idiom":"iphone", "filename":"appicon_40.png", "scale":"2x" },
    { "size":"20x20", "idiom":"iphone", "filename":"appicon_80.png", "scale":"3x" },
    { "size":"29x29", "idiom":"iphone", "filename":"appicon_58.png", "scale":"2x" },
    { "size":"29x29", "idiom":"iphone", "filename":"appicon_87.png", "scale":"3x" },
    { "size":"40x40", "idiom":"iphone", "filename":"appicon_80.png", "scale":"2x" },
    { "size":"40x40", "idiom":"iphone", "filename":"appicon_120.png", "scale":"3x" },
    { "size":"60x60", "idiom":"iphone", "filename":"appicon_120.png", "scale":"2x" },
    { "size":"60x60", "idiom":"iphone", "filename":"appicon_180.png", "scale":"3x" },
    { "size":"20x20", "idiom":"ipad", "filename":"appicon_20.png", "scale":"1x" },
    { "size":"20x20", "idiom":"ipad", "filename":"appicon_40.png", "scale":"2x" },
    { "size":"29x29", "idiom":"ipad", "filename":"appicon_29.png", "scale":"1x" },
    { "size":"29x29", "idiom":"ipad", "filename":"appicon_58.png", "scale":"2x" },
    { "size":"40x40", "idiom":"ipad", "filename":"appicon_40.png", "scale":"1x" },
    { "size":"40x40", "idiom":"ipad", "filename":"appicon_80.png", "scale":"2x" },
    { "size":"76x76", "idiom":"ipad", "filename":"appicon_76.png", "scale":"1x" },
    { "size":"76x76", "idiom":"ipad", "filename":"appicon_152.png", "scale":"2x" },
    { "size":"83.5x83.5", "idiom":"ipad", "filename":"appicon_167.png", "scale":"2x" },
  ],
  "info": {
    "version":1, "author":"xcode"
  }
})
  File.open(File.join(icon_set_dir, "Contents.json"), "w") { |file| file.write(contents_json) }
end