Trim PNG files

conv.rb

require 'fileutils'

ROOT_PATH = File.dirname File.absolute_path(__FILE__)
src_dir   = ROOT_PATH + "/src"
dest_dir  = ROOT_PATH + "/dest"

src_dirs = Dir.glob(src_dir + '/*').select{|f| File.directory? f }

src_dirs.each do |dir|
  dir_name    = dir.split('/').last
  dest_folder = [dest_dir, dir_name].join('/')
  FileUtils.mkdir_p dest_folder

  Dir.glob(dir + '/*.{png,PNG}').each do |src_file|
    fname     = File.basename src_file
    dest_file = [dest_folder, fname].join '/'
    `convert #{src_file} -trim #{dest_file}`
  end
end