cpaxton/ros_numpy

Tools for converting ROS messages to and from numpy arrays - cross-platform

ros_numpy

Note: This is the same as the original ros_numpy package by eric-wieser just edited to be OS independent and installable using pip. Loosely tested, but works perfectly on Windows and Ubuntu for "numpifying" PointCloud2 and Image messages from bag files.

Install using:

pip install rosnumpy

Quick Start

PointCloud2 msg to Numpy array:

import ros_numpy
import sensor_msgs

def get_pc_from_ros_pc2_msg(msg):
    """ Returns point-cloud as a structured numpy array. 
    Note: can be used with any topic of message type 'sensor_msgs/PointCloud2'
    """
    msg.__class__ = sensor_msgs.msg.PointCloud2
    return ros_numpy.numpify(msg)

pc_array =  get_pc_from_pc2_msg(msg)

Image msg to Numpy array:

import ros_numpy
import sensor_msgs

def get_img_from_ros_image_msg(msg):
    """ Returns image as a numpy array. 
    Note: can be used with any topic of message type 'sensor_msgs/Image'
    """
    msg.__class__ = sensor_msgs.msg.Image
    return ros_numpy.numpify(msg)

img_array =  get_img_from_ros_image_msg(msg)

The (msg) in previous examples is coming from here:

import rosbag

bag_path = r'path to .bag file here'
bag = rosbag.Bag(bag_path)
for topic, msg, t in bag.read_messages(topics=['/PointCloud2_topic_here']):
    pc_array =  get_pc_from_pc2_msg(msg)