Method and apparatus for processing binary data

A method for processing binary data prior to recording, comprising the steps of:

• dividing the binary data into 4-bit data segments;
• converting the 4-bit data segments to 8-bit codes according to a predetermined encoding transfer function describing the relationship between said 4-bit data segments and corresponding 8-bit codes, wherein the bit pattern of each said 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of from at least two "0" bits to at most nine "0" bits with an adjacent 8-bit code;
• generating a frame synchronization code;
• serially combining said 8-bit codes and said frame synchronization code to form a frame of binary digits,
• the converting step comprising checking the boundary bit pattern of the serially combined 8-bit codes which occurs between adjacent 8-bit codes against one or more predetermined boundary conditions for detecting a match therebetween;
• and
• generating a said 8-bit code in response to said transfer function and said match.

A method for processing binary data prior to recording, comprising the steps of:

• dividing the binary data into 4-bit data segments;
• converting the 4-bit data segments to 8-bit codes according to a predetermined encoding transfer function describing the relationship between said 4-bit data segments and corresponding 8-bit codes, wherein the bit pattern of each said 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of from at least two "0" bits to at most nine "0" bits with an adjacent 8-bit code;
• generating a frame synchronization code;
• serially combining said 8-bit codes and said frame synchronization code to form a frame of binary digits,
• the converting step comprising checking the bit patterns of adjacent ones of said 4-bit data segments against one or more predetermined bit patterns for detecting a match therebetween;
• and
• generating a said 8-bit code in response to said transfer function and said match.

A method for processing binary data prior to recording, comprising the steps of:

• dividing the binary data into 4-bit data segments;
• converting the 4-bit data segments to 8-bit codes according to a predetermined encoding transfer function describing the relationship between said 4-bit data segments and corresponding 8-bit codes, wherein the bit pattern of each said 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of from at least two "0" bits to at most nine "0" bits with an adjacent 8-bit code;
• generating a frame synchronization code;
• serially combining said 8-bit codes and said frame synchronization code to form a frame of binary digits,
• wherein said frame synchronization code comprises one of the following bit patterns:
• "00100100100100100100100100100XXX"
• "XXX00100100100100100100100100100" and
• "0Y001000000010010010000000100100", where "XXX" represents one of "000", "100", "010" and "001", and "Y" represents one of "1" and "0", and wherein said frame synchronization code is generated by the steps of:
• generating a pseudo-frame synchronization bit pattern;
• interleaving said pseudo-frame synchronization bit pattern with said binary data to thereby allow said pseudo-frame synchronization bit pattern to be divided into 4-bit segments and converted to a bit pattern the boundary conditions of which are identical to the boundary conditions of said frame synchronization code, and
• replacing the last-mentioned bit pattern with said frame synchronization code.

A method for processing binary data prior to recording, comprising the steps of:

• dividing the binary data into 4-bit data segments;
• converting the 4-bit data segments to 8-bit codes according to a predetermined encoding transfer function describing the relationship between said 4-bit data segments and corresponding 8-bit codes, wherein the bit pattern of each said 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of from at least two "0" bits to at most nine "0" bits with an adjacent 8-bit code;
• generating a frame synchronization code;
• serially combining said 8-bit codes and said frame synchronization code to form a frame of binary digits,
• wherein said frame synchronization code is generated by the steps of:
• generating a pseudo-frame synchronization bit pattern;
• interleaving said pseudo-frame synchronization bit pattern with said binary data to thereby allow said pseudo-frame synchronization bit pattern to be divided into 4-bit segments and converted to a bit pattern the boundary conditions of which are identical to the boundary conditions of said frame synchronization code, and
• replacing the last-mentioned bit pattern with said frame synchronization code.

A method for processing binary data prior to recording, comprising the steps of:

• dividing the binary data into 4-bit data segments;
• converting the 4-bit data segments to 8-bit codes according to a predetermined encoding transfer function describing the relationship between said 4-bit data segments and corresponding 8-bit codes, wherein the bit pattern of each said 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of from at least two "0" bits to at most nine "0" bits with an adjacent 8-bit code;
• generating a frame synchronization code;
• serially combining said 8-bit codes and said frame synchronization code to form a frame of binary digits,
• reproducing the 8-bit codes and frame synchronization code of said frame from said recording medium;
• checking the boundary bit pattern of the recorded 8-bit codes which occurs between adjacent 8-bit codes against one or more predetermined boundary conditions for detecting a match therebetween to generate a parameter of a predetermined decoding transfer function which is inverse to said encoding transfer function;
• converting the 8-bit code to a 4-bit data segment in accordance with said decoding transfer function and said parameter;
• and
• serially combining said converted 4-bit data segments to recover the original binary data.

Apparatus for processing binary data comprising:

• first serial-to-parallel shift register means receptive of said binary data for dividing the binary data into 4-bit data segments;
• encoding means having a predetermined encoding transfer function describing the relationships between said 4-bit data segment and corresponding 8-bit codes for translating said 4-bit data segment to a said 8-bit code according to the transfer function, wherein the bit pattern of said translated 8-bit code has an intra-code run-length of at least two "0" bits and forms an inter-code run-length of at most nine "0" bits with an adjacent 8-bit code;
• second parallel-to-serial shift register means connected to receive said 8-bit code from said encoding means;
• timing means for sequentially shifting binary digits in said first and second shift register means;
• means for generating a frame synchronization code;
• means for interleaving said frame synchronization code with the output of said second shift register means to form a frame of binary digits;
• and
• means for recording the binary digits of said frame in a magnetic recording medium.