mpv/audio/filter/af_sweep.c

87 lines
2.1 KiB
C

/*
* 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
const 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}
},
};