1 /*
2 Copyright (C) 2021 The Blosc Developers <blosc@blosc.org>
3 https://blosc.org
4 License: BSD 3-Clause (see LICENSE.txt)
5
6 Example program demonstrating use of the Blosc filter from C code.
7
8 To compile this program:
9
10 $ gcc -O frame_backed_schunk.c -o frame_backed_schunk -lblosc2
11
12 To run:
13
14 $ ./frame_backed_schunk
15 Blosc version info: 2.0.0a6.dev ($Date:: 2018-05-18 #$)
16 Compression ratio: 381.5 MB -> 12.2 MB (31.2x)
17 Time for append data to a schunk backed by an in-memory frame: 0.0892 s, 4278.1 MB/s
18 Compression ratio: 381.5 MB -> 12.2 MB (31.2x)
19 Time for append data to a schunk backed by a fileframe: 0.107 s, 3556.3 MB/s
20 Successful roundtrip data <-> schunk (frame-backed) !
21
22 */
23
24 #include <stdio.h>
25 #include <assert.h>
26 #include <blosc2.h>
27
28 #define KB 1024.
29 #define MB (1024*KB)
30 #define GB (1024*MB)
31
32 #define CHUNKSIZE (1000 * 1000)
33 #define NCHUNKS 100
34 #define NTHREADS 4
35
36
main(void)37 int main(void) {
38 static int32_t data[CHUNKSIZE];
39 static int32_t data_dest1[CHUNKSIZE];
40 static int32_t data_dest2[CHUNKSIZE];
41 size_t isize = CHUNKSIZE * sizeof(int32_t);
42 int64_t nbytes, cbytes;
43 int i, nchunk;
44 int nchunks;
45 blosc_timestamp_t last, current;
46 double ttotal;
47
48 printf("Blosc version info: %s (%s)\n",
49 BLOSC_VERSION_STRING, BLOSC_VERSION_DATE);
50
51 // Compression and decompression parameters
52 blosc2_cparams cparams = BLOSC2_CPARAMS_DEFAULTS;
53 cparams.typesize = sizeof(int32_t);
54 cparams.clevel = 9;
55 cparams.nthreads = NTHREADS;
56 blosc2_dparams dparams = BLOSC2_DPARAMS_DEFAULTS;
57 dparams.nthreads = NTHREADS;
58
59 /* Create a new super-chunk backed by an in-memory frame */
60 blosc2_storage storage = {.contiguous=true, .cparams=&cparams, .dparams=&dparams};
61 blosc2_schunk* schunk1 = blosc2_schunk_new(&storage);
62
63 blosc_set_timestamp(&last);
64 for (nchunk = 0; nchunk < NCHUNKS; nchunk++) {
65 for (i = 0; i < CHUNKSIZE; i++) {
66 data[i] = i * nchunk;
67 }
68 nchunks = blosc2_schunk_append_buffer(schunk1, data, isize);
69 assert(nchunks == nchunk + 1);
70 }
71 /* Gather some info */
72 nbytes = schunk1->nbytes;
73 cbytes = schunk1->cbytes;
74 blosc_set_timestamp(¤t);
75 ttotal = blosc_elapsed_secs(last, current);
76 printf("Compression ratio: %.1f MB -> %.1f MB (%.1fx)\n",
77 nbytes / MB, cbytes / MB, (1. * nbytes) / cbytes);
78 printf("Time for append data to a schunk backed by an in-memory frame: %.3g s, %.1f MB/s\n",
79 ttotal, nbytes / (ttotal * MB));
80
81 /* Create a new super-chunk backed by an in-memory frame */
82 storage = (blosc2_storage){.contiguous=true, .cparams=&cparams, .dparams=&dparams};
83 blosc2_schunk* schunk2 = blosc2_schunk_new(&storage);
84
85 blosc_set_timestamp(&last);
86 for (nchunk = 0; nchunk < NCHUNKS; nchunk++) {
87 for (i = 0; i < CHUNKSIZE; i++) {
88 data[i] = i * nchunk;
89 }
90 nchunks = blosc2_schunk_append_buffer(schunk2, data, isize);
91 assert(nchunks == nchunk + 1);
92 }
93 /* Gather some info */
94 nbytes = schunk2->nbytes;
95 cbytes = schunk2->cbytes;
96 blosc_set_timestamp(¤t);
97 ttotal = blosc_elapsed_secs(last, current);
98 printf("Compression ratio: %.1f MB -> %.1f MB (%.1fx)\n",
99 nbytes / MB, cbytes / MB, (1. * nbytes) / cbytes);
100 printf("Time for append data to a schunk backed by a fileframe: %.3g s, %.1f MB/s\n",
101 ttotal, nbytes / (ttotal * MB));
102
103 /* Retrieve and decompress the chunks from the super-chunks and compare values */
104 for (nchunk = 0; nchunk < NCHUNKS; nchunk++) {
105 int32_t dsize1 = blosc2_schunk_decompress_chunk(schunk1, nchunk, data_dest1, isize);
106 if (dsize1 < 0) {
107 printf("Decompression error in schunk1. Error code: %d\n", dsize1);
108 return dsize1;
109 }
110 int32_t dsize2 = blosc2_schunk_decompress_chunk(schunk2, nchunk, data_dest2, isize);
111 if (dsize2 < 0) {
112 printf("Decompression error in schunk2. Error code: %d\n", dsize2);
113 return dsize2;
114 }
115 assert(dsize1 == dsize2);
116 /* Check integrity of the last chunk */
117 for (i = 0; i < CHUNKSIZE; i++) {
118 assert (data_dest1[i] == i * nchunk);
119 assert (data_dest2[i] == i * nchunk);
120 }
121 }
122
123 printf("Successful roundtrip data <-> schunk (frame-backed) !\n");
124
125 /* Free resources */
126 blosc2_schunk_free(schunk1);
127 blosc2_schunk_free(schunk2);
128
129 return 0;
130 }
131