// v stdin piši S8 zvočne podatke z 8000 vzorci na sekundo
// frekvence:
// 2100 Hz BAND
// 800 Hz MONI
// 1000 Hz CALL
// 1450 Hz VFO/MR
// 1750 Hz A/B
// DTMF:
// 1209 Hz 1336 Hz 1477 Hz 1633 Hz
// 697 1 2 3 A
// 770 4 5 6 B
// 852 7 8 9 C
// 941 * 0 # D
// ffmpeg -f alsa -ac 1 -i hw:5 -f s8 -ar 8000 - | ./a.out
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <complex.h>
#include <error.h>
#include <errno.h>
#include <sys/param.h> // for MIN, MAX
int main (void) {
if (setvbuf(stdout, NULL, _IOFBF, 0))
error_at_line(1, errno, __FILE__, __LINE__, "setvbuf");
#define SAMPLES 256
int samples[SAMPLES] = { 0 };
double povprečje = 0;
int frekvence[] = {1209, 1336, 1477, 1633, 697, 770, 852, 941, 2100, 800, 1000, 1450, 1750};
#define FREKVENC 13
// int frekvence[] = {2100, 800, 1000, 1450, 1750, 1208, 1209, 1210, 1335, 1336, 1337, 1476, 1477, 1478, 1632, 1633, 1634, 696, 697, 698, 769, 770, 771, 851, 852, 853, 940, 941, 942};
/* #define FREKVENC 60
int frekvence[FREKVENC+1];
for (int i = 0; i < FREKVENC; i++)
// frekvence[i] = 1000-(FREKVENC*10/2)+i*10;
frekvence[i] = i*100; */
complex sums[FREKVENC] = { 0 };
unsigned sample = 0;
int received = 0;
char znak = '\0';
while ((received = getchar()) != EOF) {
unsigned char intermed = received;
char recvd = *(char *) &intermed;
povprečje = (povprečje*SAMPLES+abs(recvd)-abs(samples[sample % SAMPLES]))/SAMPLES;
if (!(sample % SAMPLES))
printf("\033[2J\npovprečje: %f\n", povprečje);
for (int frekvenca = 0; frekvenca < FREKVENC; frekvenca++) {
#define RATE 8000
// sums[frekvenca] -= (complex) samples[sample % SAMPLES]*cpow(M_E, (complex) -2*M_PI*I*(complex) frekvence[frekvenca]/(complex) RATE);
sums[frekvenca] += recvd*cpow(M_E, -2*M_PI*I*frekvence[frekvenca]*sample/RATE);
sums[frekvenca] -= samples[sample % SAMPLES]*cpow(M_E, -2*M_PI*I*frekvence[frekvenca]*(sample-SAMPLES)/RATE);
if (!(sample % SAMPLES)) {
printf("%d\t", frekvence[frekvenca]);
// for (int i = 0; i < pow(cabs(sums[frekvenca])/100, 2)/100; i++)
for (int i = 0; i < cabs(sums[frekvenca])/256; i++)
printf("#");
printf("\n");
}
}
if (!(sample % SAMPLES)) {
int najv[3] = {0};
double val[3] = {0};
for (int i = 0; i < FREKVENC; i++)
for (int j = 0; j < 3; j++)
if (cabs(sums[i]) > val[j]) {
for (int k = 2; k > j; k--) {
najv[k] = najv[k-1];
val[k] = val[k-1];
}
najv[j] = i;
val[j] = cabs(sums[i]);
break;
}
char trenutni = '\0';
if (val[1] > val[0]/3 && val[2] < val[1]/3) {
int večja = MAX(frekvence[najv[0]], frekvence[najv[1]]);
int manjša = MIN(frekvence[najv[0]], frekvence[najv[1]]);
char znaki[4][4] = {{'1', '2', '3', 'A'}, {'4', '5', '6', 'B'}, {'7', '8', '9', 'C'}, {'*', '0', '#', 'D'}};
int getidx (int freq) {
int i;
for (i = 0; i < 8; i++)
if (freq == frekvence[i])
return i%4;
return -1;
}
if (getidx(manjša) == -1 || getidx(večja) == -1)
trenutni = '\0';
else
trenutni = znaki[getidx(manjša)][getidx(večja)];
}
if (val[1] < val[0]/3 && najv[0] > 7) {
char znaki[] = "PSZVM";
trenutni = znaki[najv[0]-8];
}
if (znak == trenutni && znak)
printf("tipka: %c\n", znak);
znak = trenutni;
fflush(stdout);
}
samples[sample++ % SAMPLES] = recvd;
}
}
