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/*
Copyright (c) 2021 Blosc Development Team <blosc@blosc.org>
https://blosc.org
License: BSD 3-Clause (see LICENSE.txt)
Example program demonstrating the use of a Blosc from C code.
To compile this program:
$ gcc -O simple.c -o simple -lblosc2
To run:
$ ./simple
Blosc version info: 2.2.1.dev ($Date:: 2022-07-05 #$)
Compression: 40000000 -> 172176 (232.3x)
Correctly extracted 5 elements from compressed chunk!
Decompression successful!
Successful roundtrip!
*/
#include <stdio.h>
#include <inttypes.h>
#include "blosc2.h"
#define SIZE (10 * 1000 * 1000)
#define NTHREADS 2
int main(void) {
static float data[SIZE];
static float data_out[SIZE];
static float data_dest[SIZE];
float data_subset[5];
float data_subset_ref[5] = {5, 6, 7, 8, 9};
size_t isize = SIZE * sizeof(float), osize = SIZE * sizeof(float);
int dsize = SIZE * sizeof(float), csize;
int i, ret;
/* Initialize the Blosc compressor */
blosc2_init();
blosc2_set_nthreads(NTHREADS);
printf("Blosc version info: %s (%s)\n",
BLOSC2_VERSION_STRING, BLOSC2_VERSION_DATE);
for (i = 0; i < SIZE; i++) {
data[i] = (float)i;
}
/* Compress with clevel=5 and shuffle active */
csize = blosc1_compress(5, BLOSC_BITSHUFFLE, sizeof(float), isize, data,
data_out, osize);
if (csize == 0) {
printf("Buffer is incompressible. Giving up.\n");
return 1;
}
else if (csize < 0) {
printf("Compression error. Error code: %d\n", csize);
return csize;
}
printf("Compression: %" PRId64 " -> %d (%.1fx)\n",
(int64_t)isize, csize, (1. * (double)isize) / csize);
ret = blosc1_getitem(data_out, 5, 5, data_subset);
if (ret < 0) {
printf("Error in blosc1_getitem(). Giving up.\n");
return 1;
}
for (i = 0; i < 5; i++) {
if (data_subset[i] != data_subset_ref[i]) {
printf("blosc1_getitem() fetched data differs from original!\n");
return -1;
}
}
printf("Correctly extracted 5 elements from compressed chunk!\n");
/* Decompress */
dsize = blosc1_decompress(data_out, data_dest, (size_t)dsize);
if (dsize < 0) {
printf("Decompression error. Error code: %d\n", dsize);
return dsize;
}
printf("Decompression successful!\n");
for (i = 0; i < SIZE; i++) {
if (data[i] != data_dest[i]) {
printf("Decompressed data differs from original!\n");
return -1;
}
}
printf("Successful roundtrip!\n");
/* After using it, destroy the Blosc environment */
blosc2_destroy();
return 0;
}
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