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Only released in EOL distros:   electric fuerte groovy

Description

A collection of helper functions for the pi_vision stack for subscribing to image topics, converting them to OpenCV format for further processing by other nodes, and displaying processed images and markers.

How To Use

• To launch a ros2opencv node using the Kinect RGB-D camera, use:

$ roslaunch ros2opencv openni_node.launch

• To launch a ros2opencv node using a UVC-compatible webcam, use:

$ roslaunch ros2opencv uvc_cam.launch

• To load an AVI file and re-publish it on the topic /camera/image_raw:

$ roslaunch ros2opencv avi2ros.launch input:=/path/to/avi/file

• To publish the video on a different topic, use rosrun instead of roslaunch:

$ rosrun ros2opencv avi2ros.py _input:=/path/to/avi/file output:=/your_topic

(Note the underscore in front of _input but not in front of output.)

Nodes

ros2opencv.py

A ROS node for subscribing to a ROS image topic, converting the image to OpenCV format, then displaying the processed image to the user along with possible text and graphic markers.

Subscribed Topics

~input_rgb_image (sensor_msgs/Image)

• The ROS image topic to convert to OpenCV for further processing, e.g. /camera/rgb/image_color when using a Kinect and the openni_camera package.

~input_depth_image (sensor_msgs/Image)

• The ROS image topic containing depth information, e.g. /camera/depth/image when using a Kinect and the openni_camera package.

Published Topics

/output_image (remapped in pi_face_tracker launch files to /pi_face_tracker/image) (sensor_msgs/Image)

• The display image including markers republished from OpenCV to ROS

avi2ros.py

A ROS node for reading an AVI video file using OpenCV and re-publishing it as a ROS image topic. See the same launch file commands lines above for usage.

Published Topics

/output (sensor_msgs/Image)

• The ROS Image stream corresponding to the input AVI file. Can be remapped on the command line or in a launch file.

Parameters

~input (str, default: None)

• Path to the AVI file to re-publish on the /output topic.

~start_paused (boolean, default: False)

• Start the video in the paused state. Useful if you want to select a region before the video starts.

~loop (boolean, default: False)

• Continuously loop the video once it reaches the end.

~fps (int, default: 25)

• Run the video at fps frames per second.