Downbeat and upbeat are detected alternatively

[LinChihShan]

Hi, thank you again for sharing this library!

I have observed that this algorithm outputs downbeat/upbeat alternatively.
For example we have a 30-second music piece, in the first 15 second, we get the downbeats from the algorithm. Then from 15 second, the algorithm starts to output the upbeats to the end of music piece.

It is possible that the downbeat/upbeat switching mentioned above happens many time in a music piece.
But in my application a stable beat interval is needed(all-downbeat or all-upbeat will be good).
So I am wondering the reason and how to overcome this.

Thanks in advance!