gistfile1.txt

$ ./zopfli -h
Usage: zopfli [OPTION]... FILE
  -h    gives this help
  -c    write the result on standard output, instead of disk filename + '.gz'
  -v    verbose mode
  --gzip  output to gzip format (default)
  --deflate  output to deflate format instead of gzip
  --zlib  output to zlib format instead of gzip
  --i5  less compression, but faster
  --i10  less compression, but faster
  --i15  default compression, 15 iterations
  --i25  more compression, but slower
  --i50  more compression, but slower
  --i100  more compression, but slower
  --i250  more compression, but slower
  --i500  more compression, but slower
  --i1000  more compression, but slower