|Build Status|

PYZOPFLI
========

cPython bindings for
`zopfli <http://googledevelopers.blogspot.com/2013/02/compress-data-more-densely-with-zopfli.html>`__.

It requires Python 3.8 or greater.

USAGE
=====

pyzopfli is a straight forward wrapper around zopfli's ZlibCompress method.

::

    from zopfli.zlib import compress
    from zlib import decompress
    s = 'Hello World'
    print decompress(compress(s))

pyzopfli also wraps GzipCompress, but the API point does not try to
mimic the gzip module.

::

    from zopfli.gzip import compress 
    from StringIO import StringIO
    from gzip import GzipFile
    print GzipFile(fileobj=StringIO(compress("Hello World!"))).read()

Both zopfli.zlib.compress and zopfli.gzip.compress support the following
keyword arguments. All values should be integers; boolean parmaters are
treated as expected, 0 and >0 as false and true.

-  *verbose* dumps zopfli debugging data to stderr

-  *numiterations* Maximum amount of times to rerun forward and backward
   pass to optimize LZ77 compression cost. Good values: 10, 15 for small
   files, 5 for files over several MB in size or it will be too slow.

-  *blocksplitting* If true, splits the data in multiple deflate blocks
   with optimal choice for the block boundaries. Block splitting gives
   better compression. Default: true (1).

-  *blocksplittinglast* If true, chooses the optimal block split points
   only after doing the iterative LZ77 compression. If false, chooses
   the block split points first, then does iterative LZ77 on each
   individual block. Depending on the file, either first or last gives
   the best compression. Default: false (0).

-  *blocksplittingmax* Maximum amount of blocks to split into (0 for
   unlimited, but this can give extreme results that hurt compression on
   some files). Default value: 15.

TODO
====

-  Stop reading the entire file into memory and support streaming

-  Monkey patch zlib and gzip so code with an overly tight binding can
   be easily modified to use zopfli.

.. |Build Status| image:: https://github.com/fonttools/py-zopfli/actions/workflows/ci.yml/badge.svg?branch=master
   :target: https://github.com/fonttools/py-zopfli/actions/workflows/ci.yml
