摘要 |
<p>A method of processing digital information prior to recording comprises converting input digital words into code words, each of the same period as the input digital word but containing a greater number of time slots than the number of bit locations in the digital word, providing a plurality of groups of code words and selecting the group from which a code word will be taken in any instance on the basis of the immediately preceding code word. The code words are defined such that there is a minimum spacing of three time slots between transitions and no transition is permitted in the last time slot. Two main groups of code words are provided which each have a transformed version. Apparatus for carrying out the method as described as is apparatus for decoding the encode words in replay.</p> |