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// Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
// #inlcude <GPL_v2.h>
#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_s* af, int cmd, void* arg)
{
af_sweept* s = (af_sweept*)af->setup;
af_data_t *data= (af_data_t*)arg;
switch(cmd){
case AF_CONTROL_REINIT:
af->data->nch = data->nch;
af->data->format = AF_FORMAT_S16_NE;
af->data->bps = 2;
af->data->rate = data->rate;
return AF_OK;
case AF_CONTROL_COMMAND_LINE:
sscanf((char*)arg,"%lf", &s->delta);
return AF_OK;
/* case AF_CONTROL_RESAMPLE_RATE | AF_CONTROL_SET:
af->data->rate = *(int*)arg;
return AF_OK;*/
}
return AF_UNKNOWN;
}
// Deallocate memory
static void uninit(struct af_instance_s* af)
{
if(af->data)
free(af->data);
if(af->setup){
af_sweept *s = af->setup;
free(s);
}
}
// Filter data through filter
static af_data_t* play(struct af_instance_s* af, af_data_t* data)
{
af_sweept *s = af->setup;
int i, j;
int16_t *in = (int16_t*)data->audio;
int chans = data->nch;
int in_len = data->len/(2*chans);
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 data;
}
static int open(af_instance_t* af){
af->control=control;
af->uninit=uninit;
af->play=play;
af->mul.n=1;
af->mul.d=1;
af->data=calloc(1,sizeof(af_data_t));
af->setup=calloc(1,sizeof(af_sweept));
return AF_OK;
}
af_info_t af_info_sweep = {
"sine sweep",
"sweep",
"Michael Niedermayer",
"",
AF_FLAGS_REENTRANT,
open
};
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