GitHub/dsd-fme
1
0
Fork 0
mirror of https://github.com/lwvmobile/dsd-fme.git synced 2026-11-14 01:37:25 -05:00
Code Issues Packages Projects Releases Wiki Activity

rtl_sdr_fm: guard and document bandwidth_multiplier behavior

Browse Source
This commit is contained in:
arancormonk
2025-09-03 20:23:52 -04:00
parent 0cb38d2c25
commit ac8f17bf20
1 changed files with 18 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/rtl_sdr_fm.cpp
View File

@@ -50,6 +50,9 @@
#define FREQUENCIES_LIMIT 1000
/* Clamp for bandwidth upsampling multiplier to avoid extreme expansion */
#define MAX_BANDWIDTH_MULTIPLIER 8
static int lcm_post[17] = {1,1,1,3,1,5,3,7,1,9,5,11,3,13,7,15,1};
static int ACTUAL_BUF_LENGTH;
@@ -1738,6 +1741,21 @@ void open_rtlsdr_stream(dsd_opts *opts)
int r;
rtl_bandwidth = opts->rtl_bandwidth * 1000; //reverted back to straight value
bandwidth_multiplier = (bandwidth_divisor / rtl_bandwidth);
/* Guard multiplier to a safe range [1, MAX_BANDWIDTH_MULTIPLIER] */
{
int orig_mult = bandwidth_multiplier;
if (bandwidth_multiplier < 1) {
fprintf(stderr,
"WARNING: bandwidth_multiplier computed as %d (divisor=%d, bandwidth=%d Hz). Clamping to 1.\n",
orig_mult, bandwidth_divisor, rtl_bandwidth);
bandwidth_multiplier = 1;
} else if (bandwidth_multiplier > MAX_BANDWIDTH_MULTIPLIER) {
fprintf(stderr,
"WARNING: bandwidth_multiplier computed as %d exceeds max %d (divisor=%d, bandwidth=%d Hz). Clamping to %d.\n",
orig_mult, MAX_BANDWIDTH_MULTIPLIER, bandwidth_divisor, rtl_bandwidth, MAX_BANDWIDTH_MULTIPLIER);
bandwidth_multiplier = MAX_BANDWIDTH_MULTIPLIER;
}
}
volume_multiplier = 1; //moved to external handling to be more dynamic
//this needs to be initted first, then we set the parameters