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LZ4Frame library for Python (via C bindings)

Project description


This is an LZ4-frame compression library for Python v3.2+ (and 2.7+), bound to Yann Collet's LZ4 C implementation.

Installing / packaging

# To get from PyPI
pip3 install py-lz4framed

# To only build extension modules inline (e.g. in repository)
python3 build_ext -i

# To build & install globally
python3 install



Single-function operation:

import lz4framed

compressed = lz4framed.compress(b'binary data')

uncompressed = lz4framed.decompress(compressed)

To iteratively compress (to a file or e.g. BytesIO instance):

with open('myFile', 'wb') as f:
    # Context automatically finalises frame on completion, unless an exception occurs
    with Compressor(f) as c:
            while (...):
        except Lz4FramedNoDataError:

To decompress from a file-like object:

with open('myFile', 'rb') as f:
        for chunk in Decompressor(f):
    except Lz4FramedNoDataError:
        # Compress frame data incomplete - error case

See also lz4framed/ for example usage.


import lz4framed
print(lz4framed.__version__, lz4framed.LZ4_VERSION, lz4framed.LZ4F_VERSION)

Command-line utility

python3 -mlz4framed
USAGE: lz4framed (compress|decompress) (INFILE|-) [OUTFILE]

(De)compresses an lz4 frame. Input is read from INFILE unless set to '-', in
which case stdin is used. If OUTFILE is not specified, output goes to stdout.



This library has been checked using flake8 and pylint, using a modified configuration - see pylint.rc and flake8.cfg.


python3 -m unittest discover -v .


The only existing lz4-frame interoperable implementation I was aware of at the time of writing (lz4tools) had the following limitations:

  • Incomplete implementation in terms of e.g. reference & memory leaks on failure
  • Lack of unit tests
  • Not thread safe
  • Does not release GIL during low level (de)compression operations
  • Did not address the requirements for an external project

Project details

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py-lz4framed-0.14.0.tar.gz (128.0 kB view hashes)

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