# count k-mers (see jellyfish documentation for options)
gzip -dc reads1.fastq.gz reads2.fastq.gz | jellyfish count -m 31 -o fastq.counts -C -s 10000000000 -U 500 -t 30 /dev/fd/0
# generate a histogram
jellyfish histo fastq.counts_0 > fastq.counts_0.histo
# generate a pdf graph of the histogram
jellyplot.pl fastq.counts_0.histo
# look at fastq.counts_0.histo.pdf and identify the approximate peak
# use find_valleys.pl to help pinpoint the actual peak
find_valleys.pl fastq.counts_0.histo
# estimate the size and coverage
estimate_genome_size.pl --kmer=31 --peak=42 --fastq=reads1.fastq.gz reads2.fastq.gz
Latest download link at https://sourceforge.net/projects/bbmap/files/BBMap_38.94.tar.gz