DualCtx quality score compression
To compile: g++ dualfqz.cpp sfh.cpp -o dualfqz
To compress: dualfqz -k 2 -l 5 < a.fastq > a.df
To uncompress dualfqz -d < a.df > a.fastq
DualFqz was built by substituting DualCtx for the quality score compression module in a variant of Fqzcomp (https://sourceforge.net/projects/fqzcomp/).