Files
UnrealEngine/Engine/Source/ThirdParty/Blosc/c-blosc-1.21.0/examples/many_compressors.c
2025-05-18 13:04:45 +08:00

118 lines
3.1 KiB
C

/*
Example program demonstrating use of the Blosc filter from C code.
To compile this program:
$ gcc many_compressors.c -o many_compressors -lblosc -lpthread
or, if you don't have the blosc library installed:
$ gcc -O3 -msse2 many_compressors.c ../blosc/*.c -I../blosc \
-o many_compressors -lpthread \
-DHAVE_ZLIB -lz -DHAVE_LZ4 -llz4 -DHAVE_SNAPPY -lsnappy
Using MSVC on Windows:
$ cl /Ox /Femany_compressors.exe /Iblosc many_compressors.c blosc\*.c
To run:
$ ./many_compressors
Blosc version info: 1.10.0.dev ($Date:: 2016-07-20 #$)
Using 4 threads (previously using 1)
Using blosclz compressor
Compression: 4000000 -> 158788 (25.2x)
Succesful roundtrip!
Using lz4 compressor
Compression: 4000000 -> 235419 (17.0x)
Succesful roundtrip!
Using lz4hc compressor
Compression: 4000000 -> 38314 (104.4x)
Succesful roundtrip!
Using snappy compressor
Compression: 4000000 -> 311617 (12.8x)
Succesful roundtrip!
Using zlib compressor
Compression: 4000000 -> 22103 (181.0x)
Succesful roundtrip!
Using zstd compressor
Compression: 4000000 -> 11813 (338.6x)
Succesful roundtrip!
*/
#include <stdio.h>
#include <blosc.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];
static float data_dest[SIZE];
int isize = SIZE*sizeof(float), osize = SIZE*sizeof(float);
int dsize = SIZE*sizeof(float), csize;
int nthreads, pnthreads, i;
char* compressors[] = {"blosclz", "lz4", "lz4hc", "snappy", "zlib", "zstd"};
int ccode, rcode;
for(i=0; i<SIZE; i++){
data[i] = i;
}
/* Register the filter with the library */
printf("Blosc version info: %s (%s)\n",
BLOSC_VERSION_STRING, BLOSC_VERSION_DATE);
/* Initialize the Blosc compressor */
blosc_init();
nthreads = 4;
pnthreads = blosc_set_nthreads(nthreads);
printf("Using %d threads (previously using %d)\n", nthreads, pnthreads);
/* Tell Blosc to use some number of threads */
for (ccode=0; ccode <= 5; ccode++) {
rcode = blosc_set_compressor(compressors[ccode]);
if (rcode < 0) {
printf("Error setting %s compressor. It really exists?",
compressors[ccode]);
return rcode;
}
printf("Using %s compressor\n", compressors[ccode]);
/* Compress with clevel=5 and shuffle active */
csize = blosc_compress(5, 1, sizeof(float), isize, data, data_out, osize);
if (csize < 0) {
printf("Compression error. Error code: %d\n", csize);
return csize;
}
printf("Compression: %d -> %d (%.1fx)\n", isize, csize, (1.*isize) / csize);
/* Decompress */
dsize = blosc_decompress(data_out, data_dest, dsize);
if (dsize < 0) {
printf("Decompression error. Error code: %d\n", dsize);
return dsize;
}
/* After using it, destroy the Blosc environment */
blosc_destroy();
for(i=0;i<SIZE;i++){
if(data[i] != data_dest[i]) {
printf("Decompressed data differs from original!\n");
return -1;
}
}
printf("Succesful roundtrip!\n");
}
return 0;
}