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Additional bFlags for Lat/Lon decoding

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Additional flags in the bFlags variables for even and odd CPR lat/lon
updates.

Change the interactiveReceiveData function to use the bFlags when
updating the aircraft (a) structure from the newly received (mm) message
structure. This should hopefully be faster than basically re-decoding
the DF, type and subtypes all over again.

If we decode the lat/lon into the aircraft (a) structure, back populate
it into the message (mm) structure. This allows us to print a decoded
Lat/Lon in the decoded message list output.
This commit is contained in:
Malcolm Robb 2013-05-09 18:48:07 +01:00
parent f011f07e9f
commit 735429b87a
1 changed files with 79 additions and 78 deletions
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113
dump1090.c
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@ -105,7 +105,7 @@
#define MODES_USER_LATLON_VALID (1<<0)
#define MODES_ACFLAGS_LATLON_VALID (1<<0) // Aircraft Lat/Lon is known
#define MODES_ACFLAGS_LATLON_VALID (1<<0) // Aircraft Lat/Lon is decoded
#define MODES_ACFLAGS_ALTITUDE_VALID (1<<1) // Aircraft altitude is known
#define MODES_ACFLAGS_HEADING_VALID (1<<2) // Aircraft heading is known
#define MODES_ACFLAGS_SPEED_VALID (1<<3) // Aircraft speed is known
@ -115,8 +115,13 @@
#define MODES_ACFLAGS_EWSPEED_VALID (1<<7) // Aircraft East West Speed is known
#define MODES_ACFLAGS_NSSPEED_VALID (1<<8) // Aircraft North South Speed is known
#define MODES_ACFLAGS_AOG (1<<9) // Aircraft is On the Ground
#define MODES_ACFLAGS_LLEVEN_VALID (1<<10) // Aircraft Even Lot/Lon is known
#define MODES_ACFLAGS_LLODD_VALID (1<<11) // Aircraft Odd Lot/Lon is known
#define MODES_ACFLAGS_LATLON_REL_OK (1<<15) // Indicates it's OK to do a relative CPR
#define MODES_ACFLAGS_LLEITHER_VALID (MODES_ACFLAGS_LLEVEN_VALID | MODES_ACFLAGS_LLODD_VALID)
#define MODES_ACFLAGS_LLBOTH_VALID (MODES_ACFLAGS_LLEVEN_VALID | MODES_ACFLAGS_LLODD_VALID)
#define MODES_SBS_LAT_LONG_FRESH (1<<0)
#define MODES_DEBUG_DEMOD (1<<0)
@ -296,6 +301,8 @@ struct modesMessage {
int heading; // Reported by aircraft, or computed from from EW and NS velocity
int raw_latitude; // Non decoded latitude.
int raw_longitude; // Non decoded longitude.
double fLat; // Coordinates obtained from CPR encoded data if/when decoded
double fLon; // Coordinates obtained from CPR encoded data if/when decoded
char flight[16]; // 8 chars flight number.
int ew_velocity; // E/W velocity.
int ns_velocity; // N/S velocity.
@ -1511,6 +1518,8 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
} else if (metype >= 5 && metype <= 18) { // Position Message
mm->raw_latitude = ((msg[6] & 3) << 15) | (msg[7] << 7) | (msg[8] >> 1);
mm->raw_longitude = ((msg[8] & 1) << 16) | (msg[9] << 8) | (msg[10]);
mm->bFlags |= (mm->msg[6] & 0x04) ? MODES_ACFLAGS_LLODD_VALID
: MODES_ACFLAGS_LLEVEN_VALID;
if (metype >= 9) { // Airborne
int AC12Field = ((msg[5] << 4) | (msg[6] >> 4)) & 0x0FFF;
if (AC12Field) {// Only attempt to decode if a valid (non zero) altitude is present
@ -1704,8 +1713,7 @@ void displayModesMessage(struct modesMessage *mm) {
}
}
} else if (mm->msgtype == 11) {
/* DF 11 */
} else if (mm->msgtype == 11) { // DF 11
printf("DF 11: All Call Reply.\n");
printf(" Capability : %s\n", ca_str[mm->ca]);
printf(" ICAO Address: %06x\n", mm->addr);
@ -1736,8 +1744,13 @@ void displayModesMessage(struct modesMessage *mm) {
printf(" F flag : %s\n", (mm->msg[6] & 0x04) ? "odd" : "even");
printf(" T flag : %s\n", (mm->msg[6] & 0x08) ? "UTC" : "non-UTC");
printf(" Altitude : %d feet\n", mm->altitude);
if (mm->bFlags & MODES_ACFLAGS_LATLON_VALID) {
printf(" Latitude : %f\n", mm->fLat);
printf(" Longitude: %f\n", mm->fLon);
} else {
printf(" Latitude : %d (not decoded)\n", mm->raw_latitude);
printf(" Longitude: %d (not decoded)\n", mm->raw_longitude);
}
} else if (mm->metype == 19) { // Airborne Velocity
if (mm->mesub == 1 || mm->mesub == 2) {
@ -2252,14 +2265,11 @@ struct aircraft *interactiveCreateAircraft(struct modesMessage *mm) {
if (mm->msgtype == 32) {
int modeC = ModeAToModeC(mm->modeA | mm->fs);
a->modeACflags = MODEAC_MSG_FLAG;
a->modeA = mm->modeA;
a->bFlags = mm->bFlags;
if (modeC < -12) {
a->modeACflags |= MODEAC_MSG_MODEA_ONLY;
} else {
a->modeC = modeC;
a->altitude = modeC * 100;
a->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID;
mm->altitude = modeC * 100;
mm->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID;
}
}
return (a);
@ -2604,7 +2614,13 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) {
a->timestamp = mm->timestampMsg;
a->messages++;
if (mm->msgtype == 0 || mm->msgtype == 4 || mm->msgtype == 20) {
// If a (new) CALLSIGN has been received, copy it to the aircraft structure
if (mm->bFlags & MODES_ACFLAGS_CALLSIGN_VALID) {
memcpy(a->flight, mm->flight, sizeof(a->flight));
}
// If a (new) ALTITUDE has been received, copy it to the aircraft structure
if (mm->bFlags & MODES_ACFLAGS_ALTITUDE_VALID) {
if ( (a->modeCcount) // if we've a modeCcount already
&& (a->altitude != mm->altitude ) ) // and Altitude has changed
// && (a->modeC != mm->modeC + 1) // and Altitude not changed by +100 feet
@ -2615,79 +2631,68 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) {
}
a->altitude = mm->altitude;
a->modeC = (mm->altitude + 49) / 100;
if ((mm->msgtype == 20) && (mm->msg[4] == 0x20)) {
memcpy(a->flight, mm->flight, sizeof(a->flight));
}
} else if(mm->msgtype == 5 || mm->msgtype == 21) {
// If a (new) SQUAWK has been received, copy it to the aircraft structure
if (mm->bFlags & MODES_ACFLAGS_SQUAWK_VALID) {
if (a->modeA != mm->modeA) {
a->modeAcount = 0; // Squawk has changed, so zero the hit count
a->modeACflags &= ~MODEAC_MSG_MODEA_HIT;
}
a->modeA = mm->modeA;
if ((mm->msgtype == 21) && (mm->msg[4] == 0x20)) {
memcpy(a->flight, mm->flight, sizeof(a->flight));
}
} else if (mm->msgtype == 17) {
if (mm->metype >= 1 && mm->metype <= 4) {
memcpy(a->flight, mm->flight, sizeof(a->flight));
} else if (mm->metype >= 5 && mm->metype <= 18) {
int fflag = mm->msg[6] & 0x04;
if ((a->bFlags ^ mm->bFlags) & MODES_ACFLAGS_AOG) {
a->odd_cprtime = a->even_cprtime = 0; // Change airborne = change CPR scale need new pair
a->bFlags ^= MODES_ACFLAGS_AOG; // Ground = metype 5-8, Airborne = metype 9-18
}
if (mm->metype >= 9) { // Airborne
if ( (a->modeCcount) // if we've a modeCcount already
&& (a->altitude != mm->altitude ) ) // and Altitude has changed
// && (a->modeC != mm->modeC + 1) // and Altitude not changed by +100 feet
// && (a->modeC + 1 != mm->modeC ) ) // and Altitude not changes by -100 feet
{
a->modeCcount = 0; //....zero the hit count
a->modeACflags &= ~MODEAC_MSG_MODEC_HIT;
}
a->altitude = mm->altitude;
a->modeC = (mm->altitude + 49) / 100;
} else { // Ground
a->speed = mm->velocity;
// If a (new) HEADING has been received, copy it to the aircraft structure
if (mm->bFlags & MODES_ACFLAGS_HEADING_VALID) {
a->track = mm->heading;
}
if (fflag) {
// If a (new) SPEED has been received, copy it to the aircraft structure
if (mm->bFlags & MODES_ACFLAGS_SPEED_VALID) {
a->speed = mm->velocity;
}
// if the Aircraft has landed or taken off since the last message, clear the even/odd CPR flags
if ((a->bFlags ^ mm->bFlags) & MODES_ACFLAGS_AOG) {
a->bFlags &= ~(MODES_ACFLAGS_LLBOTH_VALID | MODES_ACFLAGS_AOG);
} else if ( (mm->bFlags & MODES_ACFLAGS_LLEITHER_VALID)
&& (((mm->bFlags | a->bFlags) & MODES_ACFLAGS_LLEITHER_VALID) == MODES_ACFLAGS_LLBOTH_VALID) ) {
// If it's a new even/odd raw lat/lon, and we now have both even and odd,decode the CPR
int fflag;
if (mm->bFlags & MODES_ACFLAGS_LLODD_VALID) {
fflag = 1;
a->odd_cprlat = mm->raw_latitude;
a->odd_cprlon = mm->raw_longitude;
a->odd_cprtime = mstime();
} else {
fflag = 0;
a->even_cprlat = mm->raw_latitude;
a->even_cprlon = mm->raw_longitude;
a->even_cprtime = mstime();
}
// Try relative CPR first
if (decodeCPRrelative(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG))) {
// If it fails then try global if the two data are less than 10 seconds apart, compute
// the position.
// If it fails then try global if the two data are less than 10 seconds apart
if (abs((int)(a->even_cprtime - a->odd_cprtime)) <= 10000) {
decodeCPR(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG));
}
}
} else if (mm->metype == 19) {
if ((mm->mesub >= 1) && (mm->mesub <= 4)) {
a->speed = mm->velocity;
a->track = mm->heading;
//If we sucessfully decoded, back copy the results to mm so that we can print them in list output
if (a->bFlags & MODES_ACFLAGS_LATLON_VALID) {
mm->bFlags |= MODES_ACFLAGS_LATLON_VALID;
mm->fLat = a->lat;
mm->fLon = a->lon;
}
}
} else if(mm->msgtype == 32) {
// Update the aircrafts a->bFlags to reflect the newly received mm->bFlags;
a->bFlags |= mm->bFlags;
if (mm->msgtype == 32) {
int flags = a->modeACflags;
if ((flags & (MODEAC_MSG_MODEC_HIT | MODEAC_MSG_MODEC_OLD)) == MODEAC_MSG_MODEC_OLD) {
//
// This Mode-C doesn't currently hit any known Mode-S, but it used to because MODEAC_MSG_MODEC_OLD is
@ -2702,13 +2707,9 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) {
a->modeACflags = flags & ~MODEAC_MSG_MODEC_OLD;
a->messages = 1;
}
}
if (a->bFlags & MODES_ACFLAGS_ALTITUDE_VALID) {
mm->altitude = a->altitude;
mm->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID;
}
}
return a;
return (a);
}
/* Show the currently captured interactive data on screen. */