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#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <inttypes.h>
#include "dca.h"
#include "audio_out.h"
#include "audio_out_internal.h"
typedef struct peak_instance_s {
ao_instance_t ao;
int flags;
float peak;
} peak_instance_t;
static int peak_setup (ao_instance_t * _instance, int sample_rate, int * flags,
level_t * level, sample_t * bias)
{
peak_instance_t * instance = (peak_instance_t *) _instance;
(void)sample_rate;
(void)flags;
*flags = instance->flags;
*level = CONVERT_LEVEL;
*bias = 0;
return 0;
}
static int peak_play (ao_instance_t * _instance, int flags, sample_t * samples)
{
peak_instance_t * instance = (peak_instance_t *) _instance;
int i;
(void)flags;
for (i = 0; i < 256 * 2; i++) {
#ifdef LIBDCA_FIXED
float f = fabs (samples[i] * (1.0 / (1 << 30)));
#else
float f = fabs (samples[i]);
#endif
if (instance->peak < f)
instance->peak = f;
}
return 0;
}
static void peak_close (ao_instance_t * _instance)
{
peak_instance_t * instance = (peak_instance_t *) _instance;
printf ("peak level = %.4f (%+.2f dB)\n",
instance->peak, 6 * log (instance->peak) / log (2));
}
static ao_instance_t * peak_open (int flags)
{
peak_instance_t * instance;
instance = (peak_instance_t *) malloc (sizeof (peak_instance_t));
if (instance == NULL)
return NULL;
instance->ao.setup = peak_setup;
instance->ao.play = peak_play;
instance->ao.close = peak_close;
instance->flags = flags;
instance->peak = 0;
return (ao_instance_t *) instance;
}
ao_instance_t * ao_peak_open (void)
{
return peak_open (DCA_STEREO);
}
ao_instance_t * ao_peakdolby_open (void)
{
return peak_open (DCA_DOLBY);
}
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