Method and apparatus for generating runlength-limited coding with DC control
Patent 6002718 Issued on December 14, 1999. Estimated Expiration Date: 
October 27, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 27, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3108261 3518662 DC free encoding for data transmission system Method and apparatus for generating a noiseless sliding block code for a (1,7) channel with rate 2/3 Method for reducing the number of bits in a binary word representing a series of addresses Method and apparatus for variable length coding with reduced memory requirement Transmission system with improved decoding of a block code Method and apparatus for performing LZW data compression utilizing an associative memory 16B/20B encoder Patent #: 5663724 InventorApplicationNo. 549377 filed on 10/27/1995US Classes:375/240, BANDWIDTH REDUCTION OR EXPANSION341/58, To or from minimum d.c. level codes341/59, To or from run length limited codes341/106, Coding by table look-up techniques358/426.12, Auxiliary information transmitted (e.g., required to perform or identify decoding technique)375/292, Disparity reduction704/503AUDIO SIGNAL TIME COMPRESSION OR EXPANSION (E.G., RUN LENGTH CODING)ExaminersPrimary: Chin, WellingtonAssistant: Luther, William Attorney, Agent or FirmInternational ClassesH04L 025/34H04B 001/66 AbstractThe present invention provides a lossless coding scheme that maps unconstrained binary sequences into sequences that obey the (d,k)-RLL constraint while offering a degree of DC control. In the preferred embodiment, the channel encoder is a state machine which uses a single "overlapping" table for all states rather than using multiple tables. Recognizing that a subset of codewords in a first state xi are identical to a subset of codewords in the second state xj, the overlapping encoding table uses identical addresses for the subset of identical codewords in the first and second state. Thus addresses for more than one state may point to a single codeword. A number of input bytes can be encoded into two different codewords which have different parity of ones, thus allowing for DC control. Decoding is carried out in a state-independent manner.Other References
Field of SearchDisparity reductionMULTILEVEL With threshold level Antinoise or distortion (includes predistortion) BANDWIDTH REDUCTION OR EXPANSION To or from run length limited codes To or from minimum d.c. level codes Coding by table look-up techniques In specific code or form Data in specific format Time compression or expansion Run-length coding Lossless compression AUDIO SIGNAL BANDWIDTH COMPRESSION OR EXPANSION AUDIO SIGNAL TIME COMPRESSION OR EXPANSION (E.G., RUN LENGTH CODING) | |
