This track depicts masked sequence as determined by WindowMasker on the the 23 Oct 2015 Hepatitis B virus/GCF_000861825.2_ViralProj15428/GCF_000861825.2 genome assembly. The WindowMasker tool is included in the NCBI C++ toolkit. The source code for the entire toolkit is available from the NCBI FTP site.
To create this track, WindowMasker was run with the following parameters:
windowmasker -mk_counts true -input GCF_000861825.2_ViralProj15428.unmasked.fa -output wm_counts
windowmasker -ustat wm_counts -sdust true -input GCF_000861825.2_ViralProj15428.unmasked.fa -output windowmasker.intervals
perl -wpe 'if (s/^>lcl\|(.*)\n$//) { $chr = $1; } \
if (/^(\d+) - (\d+)/) { \
$s=$1; $e=$2+1; s/(\d+) - (\d+)/$chr\t$s\t$e/;
}' windowmasker.intervals > windowmasker.sdust.bed
The windowmasker.sdust.bed included masking for areas of the
assembly that are gap. The file was 'cleaned' to remove those areas
of masking in gaps, leaving only the sequence masking. The final
result covers 0 bases in the assembly size 3,182 for
a percent coverage of % 0.00.
Morgulis A, Gertz EM, Schäffer AA, Agarwala R. WindowMasker: window-based masker for sequenced genomes. Bioinformatics. 2006 Jan 15;22(2):134-41. PMID: 16287941