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Python wrapper for the C-Blosc2 library.

Project description

A Python wrapper for the extremely fast Blosc2 compression library


The Blosc development team









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What it is

C-Blosc2 is the new major version of C-Blosc, and is backward compatible with both the C-Blosc1 API and its in-memory format.

Python-Blosc2 is a Python package that wraps C-Blosc2, the newest version of the Blosc compressor. Currently Python-Blosc2 already reproduces the API of Python-Blosc, so it can be used as a drop-in replacement. However, there are a few exceptions for a full compatibility.

In addition, Python-Blosc2 aims to leverage the new C-Blosc2 API so as to support super-chunks, multi-dimensional arrays (NDArray), serialization and other bells and whistles introduced in C-Blosc2. Although this is always and endless process, we are have almost catched up with the full C-Blosc2 potential (with the convenience of Python :-).

Note: Python-Blosc2 is meant to be backward compatible with Python-Blosc data. That means that it can read data generated with Python-Blosc, but the opposite is not true (i.e. there is no forward compatibility).

NDArray: an N-Dimensional store

One of the latest and more exciting additions in Python-Blosc2 is the NDArray object. It can write and read n-dimensional datasets in an extremely efficient way thanks to a n-dim 2-level partitioning, allowing to slice and dice arbitrary large and compressed data in a more fine-grained way:

To wet you appetite, here it is how the NDArray object performs on getting slices orthogonal to the different axis of a 4-dim dataset:

We have blogged about this:

We also have a explanatory video on why the double partition is useful (~2 min).


Blosc is now offering Python wheels for the main OS (Win, Mac and Linux) and platforms. You can install binary packages from PyPi using pip:

pip install blosc2


The documentation is here:

Also, some examples are available on:

Building from sources

python-blosc2 comes with the C-Blosc2 sources with it and can be built in-place:

git clone
cd python-blosc2
git submodule update --init --recursive
python -m pip install -r requirements-build.txt
python build_ext --inplace

That’s all. You can proceed with testing section now.


After compiling, you can quickly check that the package is sane by running the tests:

python -m pip install -r requirements-tests.txt
python -m pytest  (add -v for verbose mode)


If curious, you may want to run a small benchmark that compares a plain NumPy array copy against compression through different compressors in your Blosc build:

PYTHONPATH=. python bench/


The software is licenses under a 3-Clause BSD license. A copy of the python-blosc2 license can be found in LICENSE.txt.

Mailing list

Discussion about this module is welcome in the Blosc list:


Please follow @Blosc2 to get informed about the latest developments.

Enjoy data!

Project details

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Source Distribution

blosc2-2.1.1.tar.gz (4.3 MB view hashes)

Uploaded source

Built Distributions

blosc2-2.1.1-cp311-cp311-win_amd64.whl (2.2 MB view hashes)

Uploaded cp311

blosc2-2.1.1-cp310-cp310-win_amd64.whl (2.2 MB view hashes)

Uploaded cp310

blosc2-2.1.1-cp39-cp39-win_amd64.whl (2.2 MB view hashes)

Uploaded cp39

blosc2-2.1.1-cp38-cp38-win_amd64.whl (2.2 MB view hashes)

Uploaded cp38

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