add the crude afc option to float_to_bits.c too

src/float_to_bits.c

@@ -17,6 +17,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
+ * 20160203: added crude AFC option --sq5bpf
  */
 
 
@@ -79,19 +80,29 @@ int main(int argc, char **argv)
 	int fd, fd_out, opt;
 
 	int opt_verbose = 0;
+	int do_afc=0;
+	float filter=0;
+	float filter_val=0.0001;
+	int ccounter=0;
 
-	while ((opt = getopt(argc, argv, "v")) != -1) {
+	while ((opt = getopt(argc, argv, "vaf:F:")) != -1) {
 		switch (opt) {
-		case 'v':
-			opt_verbose = 1;
-			break;
-		default:
-			exit(2);
+			case 'v':
+				opt_verbose++;
+				break;
+			case 'a':
+				do_afc=1;
+				break;
+			case 'f':
+				filter_val=atof(optarg);
+				break;
+			default:
+				exit(2);
 		}
 	}
 
 	if (argc <= optind+1) {
-		fprintf(stderr, "Usage: %s [-v] <infile> <outfile>\n", argv[0]);
+		fprintf(stderr, "Usage: %s [-v] [-a] [-f filter_averaging_coefficient] <infile> <outfile>\n", argv[0]);
 		exit(2);
 	}
 
@@ -119,12 +130,24 @@ int main(int argc, char **argv)
 		rc /= sizeof(*fl);
 		int i;
 		for (i = 0; i < rc; ++i) {
+#define MAXVAL 5.0 /* this is the maximum value we'll accept for the incoming floats */
+			if ((fl[i] > -MAXVAL) && (fl[i] < MAXVAL))
+				filter = filter * (1.0 - filter_val) + fl[i] * filter_val;
+			if (do_afc)
+				fl[i] = fl[i] - filter;
+
 			int sym = process_sym_fl(fl[i]);
 			sym_int2bits(sym, bits + i*2);
 			//printf("%2d %1u %1u  %f\n", rc, bits[0], bits[1], fl);
 			if (opt_verbose) {
 				printf("%1u%1u", bits[2*i + 0], bits[2*i + 1]);
 			}
+			if (do_afc && (opt_verbose > 1)) {
+				ccounter++;
+				if (ccounter > 50) {
+					printf(" AFC: %f\n",filter); ccounter=0;
+				}
+			}
 		}
 
 		rc = write(fd_out, bits, rc * 2);