Multi-tracking Kalman Filter Problem

kalman

asked 2019-02-01 08:50:20 -0600

Gab
1 ●1 ●1

updated 2019-02-01 08:52:29 -0600

I am attempting to perform a multi-tracking by means Kalman filter algorithm. I declared it as

KalmanFilter kf[2]

and I initialized it as

for(int i=0; i<kalNum; i++){ 
  kf[i].init(stateSize, measSize, contrSize, type); . . .

The problem is that when I update the filter, or I use statePost function like here

for(index=0;index<2;index++)
  kf[index].statePost = state[index];

where state variable is different for each kf tracked object, the algorithm updates BOTH kf[0] and kf[1] with the same value, actually the last one,state[1], and therefore I lose track of the first object I track. Indeed if I call

kf[0].statePost.at<float>(0)
kf[1].statePost.at<float>(0)

The result is the same!! How it is possible? They are two different c++ objects! I'm sure the indexing is correct!

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answered 2019-02-01 22:00:32 -0600

Tetragramm

7376 ●13 ●37

I'm almost certain you're making shallow Mat copies somewhere.

For example: The line

kf[index].statePost = state[index];

does not copy the values in state to statePost. It simply causes statePost to point at state[index]. I am almost certain that at some point you did something similar with the state[] array, so that instead of two different sets of values, you just overwrote the first, with the second.