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avfft.c
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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 "config.h"
20 #include "libavutil/mem.h"
21 #include "libavcodec/avfft.h"
22 
23 int main(int argc, char **argv)
24 {
25  int i;
26 #define LEN 1024
27  FFTSample *ref = av_malloc_array(LEN, sizeof(*ref));
28  FFTSample *data = av_malloc_array(LEN, sizeof(*data));
29  RDFTContext *rdft_context = av_rdft_init(10, DFT_R2C);
30  RDFTContext *irdft_context = av_rdft_init(10, IDFT_C2R);
31 
32  if (!ref || !data || !rdft_context || !irdft_context)
33  return 2;
34  for (i=0; i<LEN; i++) {
35  ref[i] = data[i] = i*456 + 123 + i*i;
36  }
37  av_rdft_calc(rdft_context, data);
38  av_rdft_calc(irdft_context, data);
39 
40  for (i=0; i<LEN; i++) {
41  if (fabs(ref[i] - data[i]/LEN*2) > 1) {
42  fprintf(stderr, "Failed at %d (%f %f)\n", i, ref[i], data[i]/LEN*2);
43  return 1;
44  }
45  }
46 
47  av_rdft_end(rdft_context);
48  av_rdft_end(irdft_context);
49  av_free(data);
50  av_free(ref);
51 
52  return 0;
53 }
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
memory handling functions
int main(int argc, char **argv)
Definition: avfft.c:23
Definition: avfft.h:73
float FFTSample
Definition: avfft.h:35
void av_rdft_calc(RDFTContext *s, FFTSample *data)
Definition: avfft.h:72
void av_rdft_end(RDFTContext *s)
RDFTContext * av_rdft_init(int nbits, enum RDFTransformType trans)
Set up a real FFT.
FFT functions.
#define LEN
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
#define av_free(p)
#define av_malloc_array(a, b)