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#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <string.h>
#include <sys/time.h>
#include "../common/sample.h"
#include "../common/iir_filter.h"
#include "../common/fm_modulation.h"
#include "../common/debug.h"
struct timeval start_tv, tv;
double duration;
int tot_samples;
#define T_START() \
gettimeofday(&start_tv, NULL); \
tot_samples = 0; \
while (1) {
#define T_STOP(what, samples) \
gettimeofday(&tv, NULL); \
duration = (double)tv.tv_sec + (double)tv.tv_usec / 1e6; \
duration -= (double)start_tv.tv_sec + (double)start_tv.tv_usec / 1e6; \
tot_samples += samples; \
if (duration >= 0.5) \
break; \
} \
printf("%s: %.3f mega samples/sec\n", what, (double)tot_samples / duration / 1e6); \
#define SAMPLES 1000
sample_t samples[SAMPLES];
float buff[SAMPLES * 2];
fm_mod_t mod;
fm_demod_t demod;
iir_filter_t lp;
int main(void)
{
fm_mod_init(&mod, 50000, 0, 0.333);
T_START()
fm_modulate(&mod, samples, SAMPLES, buff);
T_STOP("FM modulate", SAMPLES)
fm_demod_init(&demod, 50000, 0, 10000.0);
T_START()
fm_demodulate(&demod, samples, SAMPLES, buff);
T_STOP("FM demodulate", SAMPLES)
iir_lowpass_init(&lp, 10000.0 / 2.0, 50000, 1);
T_START()
iir_process(&lp, samples, SAMPLES);
T_STOP("low-pass filter (second order)", SAMPLES)
iir_lowpass_init(&lp, 10000.0 / 2.0, 50000, 2);
T_START()
iir_process(&lp, samples, SAMPLES);
T_STOP("low-pass filter (fourth order)", SAMPLES)
iir_lowpass_init(&lp, 10000.0 / 2.0, 50000, 4);
T_START()
iir_process(&lp, samples, SAMPLES);
T_STOP("low-pass filter (eigth order)", SAMPLES)
return 0;
}
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