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You can bind multiple dedicated parameters to a callback. The key is boost::bind

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to provide functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual).

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). But boost works fine here, just you cannot mix it).

You can bind multiple dedicated parameters to a callback. The key is boost::bind .

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to provide accept both functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual).

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). But boost works fine here, just you cannot mix it).

You can bind multiple dedicated parameters to a callback. The key is boost::bind.

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to accept both functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual). boost::bind works also for class methods (please also refer to the boost::bind manual).

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). But boost works fine here, just but you cannot mix it).

You can bind multiple dedicated parameters to a callback. The key is boost::bind.

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to accept both functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual). boost::bind works also for class methods (please also refer to the boost::bind manual).

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). But boost works fine here, but you cannot mix it).

PPS: According to Thomas D.'s answer, I also recommend to use ROS-Parameters and launch file arguments instead of relying on the calling arguments of your binary.

You can bind multiple dedicated parameters to a callback. The key is boost::bind.

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to accept both functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual). boost::bind works also for class methods (please also refer to the boost::bind manual).

Since you want to subscribe to an image publisher, you might take a look at image_transport. You can directly apply boost:bind according to the above example.

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). But However, boost works fine here, but you cannot mix it).

PPS: According to Thomas D.'s answer, I also recommend to use ROS-Parameters and launch file arguments instead of relying on the calling arguments of your binary.

You can bind multiple dedicated parameters to a callback. The key is boost::bind.

The subscriber interface provides an overloaded initialization function accepting a boost::function object. A boost::function object combines the possibility to accept both functions and functors.

boost::bind creates a functor that includes all your extra parameters that should be passed to the callback.

You can initiate your subscriber as follows:

ros::Subscriber sub = n.subscribe<sensor_msgs::Image> ("image_topic", 10, 
                                   boost::bind(processImagecallback, _1, argc, argv) );

_1 constitutes a placeholder for the original argument that is passed to the callback (the msg-data (image) here). If you want to pass a reference to boost::bind use boost::ref(x) or boost::cref(x) (refer to the boost manual). boost::bind works also for class methods (please also refer to the boost::bind manual).

Since you want to subscribe to an image publisher, topic, you might take a look at image_transport. You can directly apply boost:bind according to the above example.

There are also other Questions here regarding callback arguments, e.g. here.

PS: Starting from C++11 std::bind is available in the standard library. Currently, ROS does not provide the corresponding C++11 interface, since it relies on C++03 (see REP003). However, boost works fine here, but you cannot mix it).

PPS: According to Thomas D.'s answer, I also recommend to use ROS-Parameters and launch file arguments instead of relying on the calling arguments of your binary.