shallow zip-file copy from codec2 e9d726bf20

1 files changed, 170 insertions, 0 deletions

diff --git a/src/fsk_put_test_bits.c b/src/fsk_put_test_bits.c
new file mode 100644
index 0000000..7b2da34
--- /dev/null
+++ b/src/fsk_put_test_bits.c
@@ -0,0 +1,170 @@
+/*---------------------------------------------------------------------------*\
+
+  FILE........: fsk_get_test_bits.c
+  AUTHOR......: Brady O'Brien
+  DATE CREATED: January 2016
+
+  Generates a pseudorandom sequence of bits for testing of fsk_mod and
+  fsk_demod.
+
+\*---------------------------------------------------------------------------*/
+
+
+/*
+  Copyright (C) 2016 David Rowe
+
+  All rights reserved.
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License version 2.1, as
+  published by the Free Software Foundation.  This program is
+  distributed in the hope that it will be useful, but WITHOUT ANY
+  WARRANTY; without even the implied warranty of MERCHANTABILITY or
+  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+  License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include "fsk.h"
+
+#define TEST_FRAME_SIZE 100  /* must match fsk_get_test_bits.c */
+
+#define VALID_PACKET_BER_THRESH 0.1
+
+int main(int argc,char *argv[]){
+    int bitcnt,biterr,i,errs,packetcnt;
+    int framesize = TEST_FRAME_SIZE;
+    float valid_packet_ber_thresh = VALID_PACKET_BER_THRESH;
+    int packet_pass_thresh = 0;
+    float ber_pass_thresh = 0;
+    FILE *fin;
+    uint8_t *bitbuf_tx, *bitbuf_rx, abyte, abit;
+    int verbose = 1;
+    int packed_in = 0;
+    
+    char usage[] = "usage: %s [-f frameSizeBits] [-t VaildFrameBERThreshold] [-b BERPass] [-p numPacketsPass] [-k] InputOneBitPerByte\n"
+                   "  [-k] packet byte input\n";
+
+    int opt;
+    while ((opt = getopt(argc, argv, "f:b:p:hqt:k")) != -1) {
+        switch (opt) {
+        case 't':
+            valid_packet_ber_thresh = atof(optarg);
+            break;
+          case 'b':
+            ber_pass_thresh = atof(optarg);
+            break;
+        case 'p':
+            packet_pass_thresh = atoi(optarg);
+            break;
+        case 'f':
+            framesize = atoi(optarg);
+            break;
+        case 'q':
+            verbose = 0;
+            break;
+        case 'k':
+            packed_in = 1;
+            break;
+        case 'h':
+        default:
+            fprintf(stderr, usage, argv[0]);
+            exit(1);
+        }
+    }
+    if (argc == 1) {
+        fprintf(stderr, usage, argv[0]);
+        exit(1);
+    }
+
+    int bits_per_byte = 1;
+    if (packed_in) {
+        if (framesize % 8) {
+            fprintf(stderr, "framesize (-f) must be a multiple of 8 for packed byte input (-k)\n");
+            exit(1);
+        }
+        bits_per_byte = 8;
+    }
+
+    char *fname = argv[optind++];
+    if ((strcmp(fname,"-")==0) || (argc<2)){
+        fin = stdin;
+    } else {
+        fin = fopen(fname,"r");
+    }
+    
+    if(fin==NULL){
+        fprintf(stderr,"Couldn't open input file: %s\n", argv[1]);
+        exit(1);
+    }
+
+    /* allocate buffers for processing */
+    bitbuf_tx = (uint8_t*)malloc(sizeof(uint8_t)*framesize);
+    bitbuf_rx = (uint8_t*)malloc(sizeof(uint8_t)*framesize);
+    
+    /* Generate known tx frame from known seed */
+    srand(158324);
+    for(i=0; i<framesize; i++){
+	bitbuf_tx[i] = rand()&0x1;
+	bitbuf_rx[i] = 0;
+    }
+    
+    bitcnt = 0; biterr = 0; packetcnt = 0;
+    float ber = 0.5;
+    
+    while(fread(&abyte,sizeof(uint8_t),1,fin)>0){
+
+        for (int b=0; b<bits_per_byte; b++) {
+            abit = (abyte >> ((bits_per_byte-1)-b)) & 0x1;
+            
+            /* update sliding window of input bits */
+
+            for(i=0; i<framesize-1; i++) {
+                bitbuf_rx[i] = bitbuf_rx[i+1];
+            }
+            bitbuf_rx[framesize-1] = abit;
+
+            /* compare to know tx frame.  If they are time aligned, there
+               will be a fairly low bit error rate */
+
+            errs = 0;
+            for(i=0; i<framesize; i++) {
+                if (bitbuf_rx[i] != bitbuf_tx[i]) {
+                    errs++;
+                }
+            }
+            if (errs < valid_packet_ber_thresh * framesize) {
+                /* OK, we have a valid packet, so lets count errors */
+                packetcnt++;
+                bitcnt += framesize;
+                biterr += errs;
+                ber =  (float)biterr/(float)bitcnt;
+                if (verbose) {
+                    fprintf(stderr,"[%04d] BER %5.3f, bits tested %6d, bit errors %6d errs: %4d \n",
+                            packetcnt, ber, bitcnt, biterr, errs);
+                }
+            }
+        }
+    }
+ 
+    free(bitbuf_rx);
+    free(bitbuf_tx);
+
+    fclose(fin);
+
+    fprintf(stderr,"[%04d] BER %5.3f, bits tested %6d, bit errors %6d\n", packetcnt, ber, bitcnt, biterr);
+    if ((packetcnt >= packet_pass_thresh) && (ber <= ber_pass_thresh)) {
+        fprintf(stderr,"PASS\n");
+        return 0;
+    }
+    else {
+        fprintf(stderr,"FAIL\n");
+        return 1;
+    }
+}