Usage: zopfli [OPTION]... FILE...
  -h    gives this help
  -c    write the result on standard output, instead of disk filename + '.gz'
  -v    verbose mode
  --i#  perform # iterations (default 15). More gives more compression but is slower. Examples: --i10, --i50, --i1000
  --gzip        output to gzip format (default)
  --zlib        output to zlib format instead of gzip
  --deflate     output to deflate format instead of gzip
  --splitlast   ignored, left for backwards compatibility