[Note: See github issue 2006 for additional comments.]
To date, filters in the netcdf-c library referred to HDF5 style filters. The inclusion of Zarr support in the netcdf-c library (called NCZarr) creates the need to provide a new representation consistent with the way that Zarr files store filter information. For Zarr, filters are represented using the JSON notation. Each filter is defined by a JSON dictionary, and each such filter dictionary is guaranteed to have a key named "id" whose value is a unique string defining the filter algorithm: "lz4" or "bzip2", for example.
This document outlines the proposed process by which NCZarr will be able to utilize existing HDF5 filters. At the same time, it provides mechanisms to support storing filter metadata in the NCZarr container using the Zarr compliant Codec style representation of filters and their parameters.
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