data = ARGF.read
 keys = %w[id totallength wavefmt format
       pcm channels frequency bytes_per_second
         bytes_by_capture bits_per_sample
           data bytes_in_data sum
 ]
 values = data.unpack 'Z4 i Z8 i s s i i s s Z4 i s*'
 sum = values.drop(12).map(&:abs).inject(:+)
 keys.zip(values.take(12) << sum) {|k, v|
       puts "#{k.ljust 17}: #{v}"
 }