netcdf_filter.h

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/* Copyright 2018, UCAR/Unidata and OPeNDAP, Inc.
   See the COPYRIGHT file for more information. */
/*
 * In order to use any of the netcdf_XXX.h files, it is necessary
 * to include netcdf.h followed by any netcdf_XXX.h files.
 * Various things (like EXTERNL) are defined in netcdf.h
 * to make them available for use by the netcdf_XXX.h files.
*/
 
#ifndef NETCDF_FILTER_H
#define NETCDF_FILTER_H 1
 
/* API for libdispatch/dfilter.c
*/
 
/* Must match values in <H5Zpublic.h> */
#ifndef H5Z_FILTER_DEFLATE
#define H5Z_FILTER_DEFLATE 1
#define H5Z_FILTER_SHUFFLE 2
#define H5Z_FILTER_FLETCHER32 3
#endif
 
#ifndef H5Z_FILTER_SZIP
#define H5Z_FILTER_SZIP 4
#define H5_SZIP_ALLOW_K13_OPTION_MASK   1
#define H5_SZIP_CHIP_OPTION_MASK        2
#define H5_SZIP_EC_OPTION_MASK          4
#define H5_SZIP_LSB_OPTION_MASK     8
#define H5_SZIP_MSB_OPTION_MASK     16
#define H5_SZIP_NN_OPTION_MASK          32
#define H5_SZIP_MAX_PIXELS_PER_BLOCK    32
#define H5_SZIP_RAW_OPTION_MASK     128
 
#define NC_SZIP_EC 4  
#define NC_SZIP_NN 32 
#endif
 
#define H5_SZIP_ALL_MASKS (H5_SZIP_CHIP_OPTION_MASK|H5_SZIP_EC_OPTION_MASK|H5_SZIP_NN_OPTION_MASK)
 
#define NC_MAX_PIXELS_PER_BLOCK 32
 
/* Other Standard Filters */
#ifndef H5Z_FILTER_ZSTD
#define H5Z_FILTER_ZSTD 32015
#endif
#ifndef H5Z_FILTER_BZIP2
#define H5Z_FILTER_BZIP2 307
#endif
#ifndef H5Z_FILTER_BLOSC
#define H5Z_FILTER_BLOSC 32001
#endif
#ifndef BLOSC_SHUFFLE
enum BLOSC_SHUFFLE {
BLOSC_NOSHUFFLE=0,  /* no shuffle */
BLOSC_SHUFFLE=1,  /* byte-wise shuffle */
BLOSC_BITSHUFFLE=2  /* bit-wise shuffle */
};
#endif
 
/*Assumes use of c-blosc library */
#ifndef BLOSC_BLOSCLZ
enum BLOSC_SUBCOMPRESSORS {BLOSC_LZ=0, BLOSC_LZ4=1, BLOSC_LZ4HC=2, BLOSC_SNAPPY=3, BLOSC_ZLIB=4, BLOSC_ZSTD=5};
#endif
 
#if defined(__cplusplus)
extern "C" {
#endif
 
/**************************************************/
/* HDF5 Format filter functions */
 
/*Define a filter for a variable */
EXTERNL int
nc_def_var_filter(int ncid, int varid, unsigned int id, size_t nparams, const unsigned int* parms);
 
/* Learn about the first defined filter filter on a variable */
EXTERNL int
nc_inq_var_filter(int ncid, int varid, unsigned int* idp, size_t* nparams, unsigned int* params);
 
/* Support inquiry about all the filters associated with a variable */
/* As is usual, it is expected that this will be called twice: 
   once to get the number of filters, and then a second time to read the ids */
EXTERNL int nc_inq_var_filter_ids(int ncid, int varid, size_t* nfilters, unsigned int* filterids);
 
/* Learn about the filter with specified id wrt a variable */
EXTERNL int nc_inq_var_filter_info(int ncid, int varid, unsigned int id, size_t* nparams, unsigned int* params);
 
/* End HDF5 Format Declarations */
 
/**************************************************/
/* Allow user to interrogate if a filter is available*/
/* Would prefer to get list of all known filters, but HDF5 does not support that */
 
/* See if filter is available */
EXTERNL int nc_inq_filter_avail(int ncid, unsigned id);
 
/**************************************************/
/* Functions for accessing standardized filters */
 
EXTERNL int nc_def_var_bzip2(int ncid, int varid, int level);
EXTERNL int nc_inq_var_bzip2(int ncid, int varid, int* hasfilterp, int *levelp);
 
/* Note use of 'zstandard' instead of 'zstd' */
EXTERNL int nc_def_var_zstandard(int ncid, int varid, int level);
EXTERNL int nc_inq_var_zstandard(int ncid, int varid, int* hasfilterp, int *levelp);
 
EXTERNL int nc_def_var_blosc(int ncid, int varid, unsigned subcompressor, unsigned level, unsigned blocksize, unsigned addshuffle);
EXTERNL int nc_inq_var_blosc(int ncid, int varid, int* hasfilterp, unsigned* subcompressorp, unsigned* levelp, unsigned* blocksizep, unsigned* addshufflep);
 
#if defined(__cplusplus)
}
#endif
/**************************************************/
 
#endif /* NETCDF_FILTER_H */