rtl_power: linear output

src/rtl_power.c

@@ -105,6 +105,7 @@ struct tuning_state
 	int downsample_passes;  /* for the recursive filter */
 	int comp_fir_size;
 	int peak_hold;
+	int linear;
 	int bin_spec;
 	double crop;
 	int crop_i1, crop_i2;
@@ -135,6 +136,7 @@ struct misc_settings
 	int boxcar;
 	int comp_fir_size;
 	int peak_hold;
+	int linear;
 	int target_rate;
 	double crop;
 	int gain;
@@ -181,7 +183,8 @@ void usage(void)
 		"\t  try -F 0 with '-c 50%%' to hide the roll off\n"
 		"\t[-r max_sample_rate (default: 2.4M)]\n"
 		"\t  possible values are 2M to 3.2M\n"
-		"\t[-P enables peak hold (default: off)]\n"
+		"\t[-P enables peak hold (default: off/averaging)]\n"
+		"\t[-L enable linear output (default: off/dB)]\n"
 		"\t[-D direct_sampling_mode, 0 (default/off), 1 (I), 2 (Q), 3 (no-mod)]\n"
 		"\t[-O enable offset tuning (default: off)]\n"
 		"\n"
@@ -638,6 +641,7 @@ void frequency_range(char *arg, struct misc_settings *ms)
 		ts->downsample_passes = c.downsample_passes;
 		ts->comp_fir_size = ms->comp_fir_size;
 		ts->peak_hold = ms->peak_hold;
+		ts->linear = ms->linear;
 		ts->avg = (long*)malloc((1<<c.bin_e) * sizeof(long));
 		if (!ts->avg) {
 			fprintf(stderr, "Error: malloc.\n");
@@ -936,8 +940,12 @@ void csv_dbm(struct tuning_state *ts)
 		dbm  = (double)ts->avg[i];
 		dbm /= (double)ts->rate;
 		dbm /= (double)ts->samples;
-		dbm  = 10 * log10(dbm);
-		fprintf(file, "%.2f%s", dbm, sep);
+		if (ts->linear) {
+			fprintf(file, "%.5g%s", dbm, sep);
+		} else {
+			dbm = 10 * log10(dbm);
+			fprintf(file, "%.2f%s", dbm, sep);
+		}
 	}
 	for (i=0; i<len; i++) {
 		ts->avg[i] = 0L;
@@ -954,6 +962,8 @@ void init_misc(struct misc_settings *ms)
 	ms->gain = AUTO_GAIN;
 	ms->window_fn = rectangle;
 	ms->smoothing = 0;
+	ms->peak_hold = 0;
+	ms->linear = 0;
 }
 
 int main(int argc, char **argv)
@@ -983,7 +993,7 @@ int main(int argc, char **argv)
 	freq_optarg = "";
 	init_misc(&ms);
 
-	while ((opt = getopt(argc, argv, "f:i:s:r:t:d:g:p:e:w:c:F:1PD:Oh")) != -1) {
+	while ((opt = getopt(argc, argv, "f:i:s:r:t:d:g:p:e:w:c:F:1PLD:Oh")) != -1) {
 		switch (opt) {
 		case 'f': // lower:upper:bin_size
 			if (f_set) {
@@ -1047,6 +1057,9 @@ int main(int argc, char **argv)
 		case 'P':
 			ms.peak_hold = 1;
 			break;
+		case 'L':
+			ms.linear = 1;
+			break;
 		case 'D':
 			direct_sampling = atoi(optarg);
 			break;