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Fix RTL RMS so it does't return Jank Values;

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lwvmobile
2023-08-07 03:43:39 -04:00
parent 81abd65da1
commit d8395fff59
3 changed files with 11 additions and 10 deletions
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15
src/rtl_sdr_fm.cpp
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@@ -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);
}