text: Encoding methods of SOLiDzipper.
  Notes: A) The quality value in QV files from ABI SOLiD system ranges from -1 to 40, which requires 6 bit space. The remaining 2 bit space out of 1 byte can be used for storing another quality value in part. B) Csfasta files contain the sequence information in four digits, '0123', which require 2 bit space. Provided that '0', 1 byte character in csfasta files, is mapped as binary data '00', '1' as '01', '2'as '10', '3' as '11', 4 byte data '0113' can be encoded into 1 byte character 0x17(00010111) through shift operation. C) Sequence IDs are extracted from QV and csfasta files, combined, and compressed using the general purpose compression methods. D) Encoded data are stored as data blocks of fixed size. This allows for selective decoding.
  