Decompress Dectris bitshuffle lz4 data directly to indices/value arrays.

The C++ core is generated as a Python extension via c2py23 and compiles in two untranspose backends: kcb (the default) and the portable scalar kernel from upstream bitshuffle. Use bslz4_to_sparse.available_backends() / set_backend() to compare them.

After git clone:

git submodule init
git submodule update
python3 -m pip install .

To run it at ESRF:

cd test
python3 test_vs_hdf5plugin.py
python3 bench1.py