Extract data from .bag without messages built
Hi, I am looking for a way to extract data from .bag files without messages built. Is this possible?, I have some .bag files but I don't have the messages built in my system so I can't see what types they have and I can't extract data from this bags files following the tutorials steps. However, when I run "rosrun rqt_bag rqt_bag" and open my bag file, I can see the data published (data value).
So I think that this is possible but I can't find out information about how to do this.