summaryrefslogtreecommitdiffstats
path: root/audio/filter/af_sweep.c
blob: af5fc71b7813b2a910a94201a4f6d14f46a3fcd0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
/*
 * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of MPlayer.
 *
 * MPlayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * MPlayer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <math.h>

#include "config.h"
#include "af.h"

typedef struct af_sweep_s{
    double x;
    double delta;
}af_sweept;


// Initialization and runtime control
static int control(struct af_instance* af, int cmd, void* arg)
{
  struct mp_audio *data= (struct mp_audio*)arg;

  switch(cmd){
  case AF_CONTROL_REINIT:
    mp_audio_copy_config(af->data, data);
    mp_audio_set_format(af->data, AF_FORMAT_S16);

    return af_test_output(af, data);
  }
  return AF_UNKNOWN;
}

// Filter data through filter
static int filter(struct af_instance* af, struct mp_audio* data, int f)
{
  af_sweept *s = af->priv;
  int i, j;
  int16_t *in = (int16_t*)data->planes[0];
  int chans   = data->nch;
  int in_len  = data->samples;

  for(i=0; i<in_len; i++){
      for(j=0; j<chans; j++)
          in[i*chans+j]= 32000*sin(s->x*s->x);
      s->x += s->delta;
      if(2*s->x*s->delta >= 3.141592) s->x=0;
  }

  return 0;
}

static int af_open(struct af_instance* af){
  af->control=control;
  af->filter=filter;
  return AF_OK;
}

#define OPT_BASE_STRUCT af_sweept
struct af_info af_info_sweep = {
    .info = "sine sweep",
    .name = "sweep",
    .open = af_open,
    .priv_size = sizeof(af_sweept),
    .options = (const struct m_option[]) {
        OPT_DOUBLE("delta", delta, 0),
        {0}
    },
};