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Treat signal level in network messages as a (RMS) amplitude, since that

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is what was previously done and it gives us better range for small signals.

Means a sqrt() call on beast output, but this shouldn't be too bad as
it's only done once per message.
This commit is contained in:
Oliver Jowett 2015-01-22 15:28:35 +00:00
parent fac838b9ad
commit 89d6b64747
1 changed files with 5 additions and 3 deletions
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8
net_io.c
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@ -293,7 +293,7 @@ void modesSendBeastOutput(struct modesMessage *mm) {
if (0x1A == ch) {*p++ = ch; } if (0x1A == ch) {*p++ = ch; }
} }
*p++ = ch = (char) round(mm->signalLevel * 255); *p++ = ch = (char) round(sqrt(mm->signalLevel) * 255);
if (0x1A == ch) {*p++ = ch; } if (0x1A == ch) {*p++ = ch; }
for (j = 0; j < msgLen; j++) { for (j = 0; j < msgLen; j++) {
@ -569,7 +569,8 @@ int decodeBinMessage(struct client *c, char *p) {
} }
ch = *p++; // Grab the signal level ch = *p++; // Grab the signal level
mm.signalLevel = 1e-5 + (unsigned char)ch / 256.0; mm.signalLevel = ((unsigned char)ch / 256.0);
mm.signalLevel = mm.signalLevel * mm.signalLevel + 1e-5;
if (0x1A == ch) {p++;} if (0x1A == ch) {p++;}
for (j = 0; j < msgLen; j++) { // and the data for (j = 0; j < msgLen; j++) { // and the data
@ -645,7 +646,8 @@ int decodeHexMessage(struct client *c, char *hex) {
switch(hex[0]) { switch(hex[0]) {
case '<': { case '<': {
mm.signalLevel = 1e-5 + ((hexDigitVal(hex[13])<<4) | hexDigitVal(hex[14])) / 256.0; mm.signalLevel = ((hexDigitVal(hex[13])<<4) | hexDigitVal(hex[14])) / 256.0;
mm.signalLevel = mm.signalLevel * mm.signalLevel + 1e-5;
hex += 15; l -= 16; // Skip <, timestamp and siglevel, and ; hex += 15; l -= 16; // Skip <, timestamp and siglevel, and ;
break;} break;}