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/*
Copyright (C) 2009 Andrew Collette
http://h5py.alfven.org
License: BSD (see LICENSE.txt)
Example program demonstrating use of the LZF filter from C code.
To compile this program:
h5cc -DH5_USE_16_API lzf/*.c lzf_filter.c example.c -o example
To run:
$ ./example
Success!
$ h5ls -v test_lzf.hdf5
Opened "test_lzf.hdf5" with sec2 driver.
dset Dataset {100/100, 100/100, 100/100}
Location: 0:1:0:976
Links: 1
Modified: 2009-02-15 16:35:11 PST
Chunks: {1, 100, 100} 40000 bytes
Storage: 4000000 logical bytes, 174288 allocated bytes, 2295.05% utilization
Filter-0: shuffle-2 OPT {4}
Filter-1: lzf-32000 OPT {1, 261, 40000}
Type: native float
*/
#include <stdio.h>
#include "hdf5.h"
#include "lzf_filter.h"
#define SIZE 100*100*100
#define SHAPE {100,100,100}
#define CHUNKSHAPE {1,100,100}
int main(){
static float data[SIZE];
static float data_out[SIZE];
const hsize_t shape[] = SHAPE;
const hsize_t chunkshape[] = CHUNKSHAPE;
int r, i;
int return_code = 1;
hid_t fid, sid, dset, plist = 0;
for(i=0; i<SIZE; i++){
data[i] = i;
}
/* Register the filter with the library */
r = register_lzf();
if(r<0) goto failed;
sid = H5Screate_simple(3, shape, NULL);
if(sid<0) goto failed;
fid = H5Fcreate("test_lzf.hdf5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
if(fid<0) goto failed;
plist = H5Pcreate(H5P_DATASET_CREATE);
if(plist<0) goto failed;
/* Chunked layout required for filters */
r = H5Pset_chunk(plist, 3, chunkshape);
if(r<0) goto failed;
/* Use of the shuffle filter VASTLY improves performance of this
and other block-oriented compression filters. Be sure to add
this before the compression filter!
*/
r = H5Pset_shuffle(plist);
if(r<0) goto failed;
/* Note the "optional" flag is necessary, as with the DEFLATE filter */
r = H5Pset_filter(plist, H5PY_FILTER_LZF, H5Z_FLAG_OPTIONAL, 0, NULL);
if(r<0) goto failed;
dset = H5Dcreate(fid, "dset", H5T_NATIVE_FLOAT, sid, plist);
if(dset<0) goto failed;
r = H5Dwrite(dset, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, &data);
if(r<0) goto failed;
r = H5Dread(dset, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, &data_out);
if(r<0) goto failed;
for(i=0;i<SIZE;i++){
if(data[i] != data_out[i]) goto failed;
}
fprintf(stdout, "Success!\n");
return_code = 0;
failed:
if(dset>0) H5Dclose(dset);
if(sid>0) H5Sclose(sid);
if(plist>0) H5Pclose(plist);
if(fid>0) H5Fclose(fid);
return return_code;
}
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