rosbag/Tutorials/Producing filtered bag files
rosbag filter <your bagfile> turtlecom.bag 'topic == "/turtle1/command_velocity"'
Now run rosbag info on turtlecom.bag. You should see a single topic for command_velocity.
The python filter functionality can extend beyond separating out messages by topic name - we can also filter based on the actual data in the message. For instance, suppose that my original teleop of turtlesim produced the following behavior:
github上有个老哥用qt搞了gui
https://github.com/AtsushiSakai/rosbag_filter_gui
不用自己搞了 I think github should add a "like" button