xref: /third_party/ffmpeg/libavutil/tests/lls.c (revision cabdff1a)
1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#include <limits.h>
20#include <stdio.h>
21
22#include "libavutil/internal.h"
23#include "libavutil/lfg.h"
24#include "libavutil/lls.h"
25#include "libavutil/mem_internal.h"
26
27int main(void)
28{
29    LLSModel m;
30    int i, order;
31    AVLFG lfg;
32
33    av_lfg_init(&lfg, 1);
34    avpriv_init_lls(&m, 3);
35
36    for (i = 0; i < 100; i++) {
37        LOCAL_ALIGNED(32, double, var, [4]);
38        double eval;
39
40        var[0] =         (av_lfg_get(&lfg) / (double) UINT_MAX - 0.5) * 2;
41        var[1] = var[0] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
42        var[2] = var[1] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
43        var[3] = var[2] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
44        m.update_lls(&m, var);
45        avpriv_solve_lls(&m, 0.001, 0);
46        for (order = 0; order < 3; order++) {
47            eval = m.evaluate_lls(&m, var + 1, order);
48            printf("real:%9f order:%d pred:%9f var:%f coeffs:%f %9f %9f\n",
49                   var[0], order, eval, sqrt(m.variance[order] / (i + 1)),
50                   m.coeff[order][0], m.coeff[order][1],
51                   m.coeff[order][2]);
52        }
53    }
54    return 0;
55}
56