Tools for converting ROS messages to and from numpy arrays. Contains two functions:
arr = numpify(msg, ...)
- try to get a numpy object from a messagemsg = msgify(MessageType, arr, ...)
- try and convert a numpy object to a message
Currently supports:
-
sensor_msgs.msg.PointCloud2
↔ structurednp.array
:data = np.zeros(100, dtype=[ ('x', np.float32), ('y', np.float32), ('rgb', np.float32, (3,)) ]) data['x'] = np.arange(100) data['y'] = data['x']*2 data['rgb'] = np.arange(100)[:,np.newaxis] msg = ros_numpy.msgify(PointCloud2, data)
data = ros_numpy.numpify(msg)
-
sensor_msgs.msg.Image
↔ 2/3-Dnp.array
, similar to the function ofcv_bridge
, but without the dependency oncv2
-
nav_msgs.msg.OccupancyGrid
↔np.ma.array
-
geometry.msg.Vector3
↔ 1-Dnp.array
.hom=True
gives[x, y, z, 0]
-
geometry.msg.Point
↔ 1-Dnp.array
.hom=True
gives[x, y, z, 1]
-
geometry.msg.Quaternion
↔ 1-Dnp.array
,[x, y, z, w]
-
geometry.msg.Transform
↔ 4×4np.array
, the homogeneous transformation matrix -
geometry.msg.Pose
↔ 4×4np.array
, the homogeneous transformation matrix from the origin
Support for more types can be added with:
@ros_numpy.converts_to_numpy(SomeMessageClass)
def convert(my_msg):
return np.array(...)
@ros_numpy.converts_from_numpy(SomeMessageClass)
def convert(my_array):
return SomeMessageClass(...)
Any extra args or kwargs to numpify
or msgify
will be forwarded to your conversion function
-
Add simple conversions for:
geometry_msgs.msg.Inertia