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added another special case to handle un-needed waypoints from network location provider

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y20k 2016-09-30 17:33:57 +02:00
parent 63d82be36c
commit 83f674e590
1 changed files with 14 additions and 5 deletions
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app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.java
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@ -139,9 +139,11 @@ public final class LocationHelper implements TrackbookKeys {
public static boolean isNewWayPoint(Location lastLocation, Location newLocation, float averageSpeed) { public static boolean isNewWayPoint(Location lastLocation, Location newLocation, float averageSpeed) {
float distance = newLocation.distanceTo(lastLocation); float distance = newLocation.distanceTo(lastLocation);
long timeDifference = newLocation.getElapsedRealtimeNanos() - lastLocation.getElapsedRealtimeNanos(); long timeDifference = newLocation.getElapsedRealtimeNanos() - lastLocation.getElapsedRealtimeNanos();
String providerLastLocation = lastLocation.getProvider();
String providerNewLocation = newLocation.getProvider();
if (newLocation.getProvider().equals(LocationManager.NETWORK_PROVIDER)) { if (newLocation.getProvider().equals(LocationManager.NETWORK_PROVIDER)) {
// SPECIAL CASE network: plausibility check for network provider. looking for sudden location jump errors // calculate speed difference
float speedDifference; float speedDifference;
float currentSpeed = distance / ((float)timeDifference / ONE_NANOSECOND); float currentSpeed = distance / ((float)timeDifference / ONE_NANOSECOND);
if (currentSpeed > averageSpeed) { if (currentSpeed > averageSpeed) {
@ -149,14 +151,21 @@ public final class LocationHelper implements TrackbookKeys {
} else { } else {
speedDifference = averageSpeed / currentSpeed; speedDifference = averageSpeed / currentSpeed;
} }
// check if speed is high (10 m/s == 36km/h) and has doubled
// SPECIAL CASE network: plausibility check for network provider. looking for sudden location jump errors
if (averageSpeed != 0f && currentSpeed > 10f && speedDifference > 2f) { if (averageSpeed != 0f && currentSpeed > 10f && speedDifference > 2f) {
// implausible location // implausible location (speed is high (10 m/s == 36km/h) and has doubled)
return false; return false;
} }
// DEFAULT network: distance is bigger than 50 meters and time difference bigger than 12 seconds // SPECIAL CASE network: if last location came from gps. only accept location fixes with decent accuracy
return distance > 50 && timeDifference >= 12 * ONE_NANOSECOND; if (lastLocation.getProvider().equals(LocationManager.GPS_PROVIDER) && newLocation.getAccuracy() < 66) {
// network locations tend to be too in accurate
return false;
}
// DEFAULT network: distance is bigger than 30 meters and time difference bigger than 12 seconds
return distance > 30 && timeDifference >= 12 * ONE_NANOSECOND;
} else { } else {
// DEFAULT GPS: distance is bigger than 10 meters and time difference bigger than 12 seconds // DEFAULT GPS: distance is bigger than 10 meters and time difference bigger than 12 seconds