drop is a ROS node that can subscribe to a topic and republish incoming data to another topic, dropping X out of every Y incoming messages. It's mainly useful for limiting bandwidth usage, e.g., over a wireless link. It can work with any message type.
drop is part of the topic_tools package.
drop <intopic> <X> <Y> [outtopic]
Subscribe to <intopic> and drop every <X> out of <Y> messages.
intopic: Incoming topic to subscribe to
X, Y: drop X out of every Y incoming messages
outtopic: Outgoing topic to publish on (default: %intopic%_drop, e.g. when intopic is "base_scan", then it will be base_scan_drop)
e.g. drop every other message published to base_scan:
rosrun topic_tools drop base_scan 1 2