Simple script to convert a mov file to an animated gif. Requires ffmpeg.

mov2gif.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

require 'optparse'

options = {
  rate: 30,
  log: 0,
}

OptionParser.new do |opts|
  opts.banner = "Usage: mov2gif [options] file"

  opts.on("-v", "--verbose [LOG_LEVEL]", "Set logging level") do |v|
    options[:log] = v
  end

  opts.on("-r", "--rate [RATE]", "Set frame rate (Hz value, fraction or abbreviation)") do |v|
    options[:rate] = v
  end
end.parse!

in_file = ARGV.first
out_file = File.basename(in_file, ".*" ) + ".gif"
unless File.file?(in_file)
  STDERR.puts "ERROR: #{in_file} does not exist"
  exit 1
end

cmd = %[ffmpeg -i "#{in_file}" -vf "scale='min(1280,iw)':-1" -pix_fmt rgb8 -r #{options[:rate]} -f gif -v #{options[:log]} -stats #{out_file}]

puts "Converting #{in_file} to #{out_file}"
puts "--> #{cmd}"
system cmd