circuitpython/docs/library/uzlib.rst

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:mod:`uzlib` -- zlib decompression
==================================
.. include:: ../templates/unsupported_in_circuitpython.inc
.. module:: uzlib
:synopsis: zlib decompression
|see_cpython_module| :mod:`cpython:zlib`.
This module allows to decompress binary data compressed with
`DEFLATE algorithm <https://en.wikipedia.org/wiki/DEFLATE>`_
(commonly used in zlib library and gzip archiver). Compression
is not yet implemented.
Functions
---------
.. function:: decompress(data, wbits=0, bufsize=0)
Return decompressed *data* as bytes. *wbits* is DEFLATE dictionary window
size used during compression (8-15, the dictionary size is power of 2 of
that value). Additionally, if value is positive, *data* is assumed to be
zlib stream (with zlib header). Otherwise, if it's negative, it's assumed
to be raw DEFLATE stream. *bufsize* parameter is for compatibility with
CPython and is ignored.
.. class:: DecompIO(stream, wbits=0)
Create a ``stream`` wrapper which allows transparent decompression of
compressed data in another *stream*. This allows to process compressed
streams with data larger than available heap size. In addition to
values described in :func:`decompress`, *wbits* may take values
24..31 (16 + 8..15), meaning that input stream has gzip header.
.. admonition:: Difference to CPython
:class: attention
This class is MicroPython extension. It's included on provisional
basis and may be changed considerably or removed in later versions.