closed loop detection

[jasonz]

hi,
  I would like to ask DBOW2 is online or offline When used in closed loop detection.

[matlabbe]

Hi,

I think DBOW2 can be used online, however I don't think its computation is bounded over time (as the scale of the environment increases) like RTAB-Map.

cheers

[jasonz]

Thank you for your quick reply.You mean that rtmap uses online training  dictionary and the dictionary in increasing?
And I also want to know how to  choose k in kmean++?

[matlabbe]

Yes, and there is a memory management mechanism that limits the time used for dictionary update and loop closure estimation to a fixed time threshold. See the papers for more info.

I don't know about how choosing k for kmean++.

cheers,
Mathieu

[jasonz]

thanks very much!