Data recording on digital media using direction and position of recording for compression of recorded data

A method of encoding a stream of digital data for transmission and/or storage, comprising the steps of:

• defining a cell that encodes n bits in said stream of digital data, said cell having 2n−1 boundaries at different locations within said cell;
• and
• encoding different patterns of said n bits at different boundaries within said cell.

A method of encoding a stream of digital data for transmission and/or storage, comprising the steps of:

• defining a cell that encodes n bits in said stream of digital data;
• and
• encoding within each cell different patterns of values of said n bits with AC signals having different patterns and polarities based on the values of the respective bits within said cell.

A method of decoding a stream of received digital data, comprising the steps of:

• defining respective cells in said received digital data, each cell decoding n bits in said stream of received digital data;
• and
• decoding within each cell different patterns of values of said n bits based on the pattern and polarity of an AC signal detected within said cell.

A digital encoder that encodes a stream of digital data for transmission and/or storage, comprising:

• a boundary circuit responsive to at least one boundary signal to define a cell having at least two boundaries at different locations within said cell;
• and
• an encoder circuit that encodes said at least two bits such that a transition occurs at a different boundary based on the logical state of the at least two bits to define a first tier of encoding and that encodes said at least two bits such that a polarity of the transition defines a second tier of encoding.

An encoder that encodes a stream of digital data for transmission and/or storage, comprising:

• a boundary circuit responsive to at least one boundary signal to define a cell that encodes n bits in said stream of digital data, said cell having 2n−1 boundaries at different locations within said cell;
• and
• an encoder circuit that encodes different patterns of values of said n bits at different boundaries within said cell.

An encoder that encodes a stream of digital data for transmission and/or storage, comprising:

• a boundary circuit responsive to at least one boundary signal to define a cell that encodes n bits in said stream of digital data;
• and
• an encoder circuit that encodes within each cell different patterns of said n bits with AC signals having different patterns and polarities based on the values of the respective bits within said cell.

A decoder that decodes a stream of received digital data, comprising:

• a boundary circuit that defines respective cells in said received digital data, each cell decoding at least two bits for each transition in a cell, said cell having at least first and second boundaries at different locations within said cell;
• and
• a decoder circuit that decodes said received digital data by detecting a transition in said cell in a first window about said first boundary or in a second window about said second boundary and, if a transition is detected in said first window or said second window, said decoder circuit decodes said at least two bits to a unique value based on whether the transition occurred in said first window or said second window and a polarity of the transition.

A decoder for decoding a stream of received digital data, comprising:

• a boundary circuit that defines respective cells in said received digital data, each cell decoding n bits in said stream of digital data and each cell having 2n−1 boundaries at different locations within said cell;
• and
• a decoder circuit that detects a transition in said cell in a window about one of said 2n−1 boundaries and, if a transition is detected, said decoder circuit decodes different patterns of said n bits to a unique value based on which window of a cell the transition was detected in.

A decoder for decoding a stream of received digital data, comprising:

• a boundary circuit that defines respective cells in said received digital data, each cell decoding n bits in said stream of received digital data;
• and
• a decoder circuit that decodes within each cell different patterns of said n bits based on the pattern and polarity of an AC signal detected within said cell.