letters.rb

letters = [?!,?.]+(?A..?Z).to_a

characters = `figlet -f banner -w 1000 #{letters.join}`

characters_colums = characters.lines.map { |line| line.chomp.chars.map { |c| c == '#' } }.transpose

bitmaps = characters_colums.chunk(&:none?).reject(&:first).map(&:last).map(&:transpose)

bitmaps.each do |bitmap|
  bitmap.map! { |row|
    l = (8-row.size)/2
    [false]*l + row + [false]*(8-row.size-l)
  }
end

# encode them
print bitmaps.map { |bitmap|
  bitmap.reduce(:concat).each_with_index.inject(0) { |s,(e,i)| e ? s | 1<<i : s }
}.pack('Q<*')