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/* Test viterbi decoder speeds */
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <math.h>
#include <memory.h>
#include <sys/time.h>
#include <sys/resource.h>
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
#include "fec.h"
#if HAVE_GETOPT_LONG
struct option Options[] = {
{"frame-length",1,NULL,'l'},
{"frame-count",1,NULL,'n'},
{"ebn0",1,NULL,'e'},
{"gain",1,NULL,'g'},
{"verbose",0,NULL,'v'},
{"force-altivec",0,NULL,'a'},
{"force-port",0,NULL,'p'},
{"force-mmx",0,NULL,'m'},
{"force-sse",0,NULL,'s'},
{"force-sse2",0,NULL,'t'},
{NULL},
};
#endif
#define RATE (1./2.)
#define MAXBYTES 10000
double Gain = 32.0;
int Verbose = 0;
int main(int argc,char *argv[]){
int i,d,tr;
int sr=0,trials = 10000,errcnt,framebits=2048;
long long int tot_errs=0;
unsigned char bits[MAXBYTES];
unsigned char data[MAXBYTES];
unsigned char xordata[MAXBYTES];
unsigned char symbols[8*2*(MAXBYTES+6)];
void *vp;
extern char *optarg;
struct rusage start,finish;
double extime;
double gain,esn0,ebn0;
time_t t;
int badframes=0;
time(&t);
srandom(t);
ebn0 = -100;
#if HAVE_GETOPT_LONG
while((d = getopt_long(argc,argv,"l:n:te:g:vapmst",Options,NULL)) != EOF){
#else
while((d = getopt(argc,argv,"l:n:te:g:vapmst")) != EOF){
#endif
switch(d){
case 'a':
Cpu_mode = ALTIVEC;
break;
case 'p':
Cpu_mode = PORT;
break;
case 'm':
Cpu_mode = MMX;
break;
case 's':
Cpu_mode = SSE;
break;
case 't':
Cpu_mode = SSE2;
break;
case 'l':
framebits = atoi(optarg);
break;
case 'n':
trials = atoi(optarg);
break;
case 'e':
ebn0 = atof(optarg);
break;
case 'g':
Gain = atof(optarg);
break;
case 'v':
Verbose++;
break;
}
}
if(framebits > 8*MAXBYTES){
fprintf(stderr,"Frame limited to %d bits\n",MAXBYTES*8);
framebits = MAXBYTES*8;
}
if((vp = create_viterbi27(framebits)) == NULL){
printf("create_viterbi27 failed\n");
exit(1);
}
if(ebn0 != -100){
esn0 = ebn0 + 10*log10((double)RATE); /* Es/No in dB */
/* Compute noise voltage. The 0.5 factor accounts for BPSK seeing
* only half the noise power, and the sqrt() converts power to
* voltage.
*/
gain = 1./sqrt(0.5/pow(10.,esn0/10.));
printf("nframes = %d framesize = %d ebn0 = %.2f dB gain = %g\n",trials,framebits,ebn0,Gain);
for(tr=0;tr<trials;tr++){
/* Encode a frame of random data */
for(i=0;i<framebits+6;i++){
int bit = (i < framebits) ? (random() & 1) : 0;
sr = (sr << 1) | bit;
bits[i/8] = sr & 0xff;
symbols[2*i+0] = addnoise(parity(sr & V27POLYA),gain,Gain,127.5,255);
symbols[2*i+1] = addnoise(parity(sr & V27POLYB),gain,Gain,127.5,255);
}
/* Decode it and make sure we get the right answer */
/* Initialize Viterbi decoder */
init_viterbi27(vp,0);
/* Decode block */
update_viterbi27_blk(vp,symbols,framebits+6);
/* Do Viterbi chainback */
chainback_viterbi27(vp,data,framebits,0);
errcnt = 0;
for(i=0;i<framebits/8;i++){
int e = Bitcnt[xordata[i] = data[i] ^ bits[i]];
errcnt += e;
tot_errs += e;
}
if(errcnt != 0)
badframes++;
if(Verbose > 1 && errcnt != 0){
printf("frame %d, %d errors: ",tr,errcnt);
for(i=0;i<framebits/8;i++){
printf("%02x",xordata[i]);
}
printf("\n");
}
if(Verbose)
printf("BER %lld/%lld (%10.3g) FER %d/%d (%10.3g)\r",
tot_errs,(long long)framebits*(tr+1),tot_errs/((double)framebits*(tr+1)),
badframes,tr+1,(double)badframes/(tr+1));
fflush(stdout);
}
if(Verbose > 1)
printf("nframes = %d framesize = %d ebn0 = %.2f dB gain = %g\n",trials,framebits,ebn0,Gain);
else if(Verbose == 0)
printf("BER %lld/%lld (%.3g) FER %d/%d (%.3g)\n",
tot_errs,(long long)framebits*trials,tot_errs/((double)framebits*trials),
badframes,tr+1,(double)badframes/(tr+1));
else
printf("\n");
} else {
/* Do time trials */
memset(symbols,127,sizeof(symbols));
printf("Starting time trials\n");
getrusage(RUSAGE_SELF,&start);
for(tr=0;tr < trials;tr++){
/* Initialize Viterbi decoder */
init_viterbi27(vp,0);
/* Decode block */
update_viterbi27_blk(vp,symbols,framebits);
/* Do Viterbi chainback */
chainback_viterbi27(vp,data,framebits,0);
}
getrusage(RUSAGE_SELF,&finish);
extime = finish.ru_utime.tv_sec - start.ru_utime.tv_sec + 1e-6*(finish.ru_utime.tv_usec - start.ru_utime.tv_usec);
printf("Execution time for %d %d-bit frames: %.2f sec\n",trials,
framebits,extime);
printf("decoder speed: %g bits/s\n",trials*framebits/extime);
}
exit(0);
}
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