goodfeature_track

Detects the strong corners to track with the Shi-Tomasi method (cv::goodFeaturesToTrack()), and publishes their positions.

opencv_apps

1.11 and later (ROS 1), 3.0.0 and later (ROS 2)

ROS

noetic, ROS One, jazzy, kilted, lyrical and later

OpenCV

any version of the distributions

Group

Features and shapes, the nodes of which publish ~/corners (Point2DArrayStamped), ~/lines (LineArrayStamped), ~/circles (CircleArrayStamped) and ~/contours (ContourArrayStamped, ~/hulls of convex_hull), by the kind of the features

demo of goodfeature_track

Usage

# ROS 2
ros2 launch opencv_apps goodfeature_track.launch.xml image:=/camera/image_raw debug_view:=false
# ROS 1
roslaunch opencv_apps goodfeature_track.launch image:=/camera/image_raw debug_view:=false

Try it with the demo video

Download the input video of the demo above, publish it as image with image_publisher, and run the node on it, in the terminals:

wget https://ros-perception.github.io/opencv_apps/media/clips/street.mp4
# terminal 1: publish the video as image in a loop
ros2 run image_publisher image_publisher_node street.mp4 --ros-args -p publish_rate:=10.0 -r image_raw:=image
# terminal 2: run the node with the parameters of the demo
ros2 launch opencv_apps goodfeature_track.launch.xml image:=image max_corners:=50
# terminal 3: view the result
ros2 run rqt_image_view rqt_image_view /goodfeature_track/image

In ROS 1:

# terminal 1
rosrun image_publisher image_publisher street.mp4 _publish_rate:=10 __name:=camera
# terminal 2
roslaunch opencv_apps goodfeature_track.launch image:=camera/image_raw max_corners:=50

See Credits of the demo videos for the license of the video.

Subscribed topics

Topic

Type

image

sensor_msgs/msg/Image

Published topics

Topic

Type

~/corners

opencv_apps/msg/Point2DArrayStamped

~/image

sensor_msgs/msg/Image

Parameters

See also the common parameters.

Name

Type

Default (range)

Changed at run time

Description

max_corners

int

23 (1 - 100)

yes

Max Number of Corners

queue_size

int

3

no, restart the node

Specigy queue_size of input image subscribers

Source

src/nodelet/goodfeature_track_nodelet.cpp, launch/goodfeature_track.launch.xml