From d8395fff5964a330c0208474c5d1b42a9b63c036 Mon Sep 17 00:00:00 2001
From: lwvmobile <lwvmobile@gmail.com>
Date: Mon, 7 Aug 2023 03:43:39 -0400
Subject: [PATCH] Fix RTL RMS so it does't return Jank Values;

---
 include/dsd.h      |  4 ++--
 src/dsd_ncurses.c  |  2 +-
 src/rtl_sdr_fm.cpp | 15 ++++++++-------
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/include/dsd.h b/include/dsd.h
index 76a79b3..72db1f3 100644
--- a/include/dsd.h
+++ b/include/dsd.h
@@ -280,7 +280,7 @@ typedef struct
   int rtl_udp_port;
   int rtl_bandwidth;
   int rtl_started;
-  int rtl_rms;
+  long int rtl_rms;
   int monitor_input_audio;
   int pulse_raw_rate_in;
   int pulse_raw_rate_out;
@@ -1229,7 +1229,7 @@ void cleanup_rtlsdr_stream();
 int get_rtlsdr_sample(int16_t *sample, dsd_opts * opts, dsd_state * state);
 void rtlsdr_sighandler();
 void rtl_dev_tune(dsd_opts * opts, long int frequency);
-int rtl_return_rms();
+long int rtl_return_rms();
 void rtl_clean_queue();
 #endif
 //DMR TRELLIS
diff --git a/src/dsd_ncurses.c b/src/dsd_ncurses.c
index 05424a7..8b66f5f 100644
--- a/src/dsd_ncurses.c
+++ b/src/dsd_ncurses.c
@@ -2290,7 +2290,7 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
       printw (" Gain: %idB;", opts->rtl_gain_value);
       printw (" PPM: %i;", opts->rtlsdr_ppm_error);
       printw (" SQ: %i;", opts->rtl_squelch_level);
-      printw (" RMS: %04i;", opts->rtl_rms);
+      printw (" RMS: %04li;", opts->rtl_rms);
       printw (" BW: %i kHz;", opts->rtl_bandwidth);
       printw (" FRQ: %i;", opts->rtlsdr_center_freq); 
     if (opts->rtl_udp_port != 0) printw ("\n| External RTL Tuning on UDP Port: %i", opts->rtl_udp_port);
diff --git a/src/rtl_sdr_fm.cpp b/src/rtl_sdr_fm.cpp
index 91bf6b4..62f860f 100644
--- a/src/rtl_sdr_fm.cpp
+++ b/src/rtl_sdr_fm.cpp
@@ -464,10 +464,11 @@ void dc_block_filter(struct demod_state *fm)
 	fm->dc_avg = avg;
 }
 
-int rms(int16_t *samples, int len, int step)
+long int rms(int16_t *samples, int len, int step)
 /* largely lifted from rtl_power */
 {
 	int i;
+	long int rms;
 	long p, t, s;
 	double dc, err;
 
@@ -481,7 +482,10 @@ int rms(int16_t *samples, int len, int step)
 	dc = (double)(t*step) / (double)len;
 	err = t * 2 * dc - dc * dc * len;
 
-	return (int)sqrt((p-err) / len);
+	rms = (long int)sqrt((p-err) / len);
+	//going with a value that's easy to figure out when its done the thing
+	if (rms < 0){ rms = 999; }
+	return rms;
 }
 
 void full_demod(struct demod_state *d)
@@ -1123,13 +1127,10 @@ void rtl_dev_tune(dsd_opts * opts, long int frequency)
 }
 
 //return RMS value (root means square) power level -- used as soft squelch inside of framesync
-int rtl_return_rms()
+long int rtl_return_rms()
 {
-	int sr = 0;
+	long int sr = 0;
 	sr = rms(demod.lowpassed, demod.lp_len, 1);
-	// 'Fix' potential negative value overflow from the rms function -- Observed in Windows builds
-	sr = abs(sr);
-	if (sr > 9999) sr = 9999;
 	return (sr);
 }