dnn_face_detection

Detect faces with YuNet (cv::FaceDetectorYN).

Face detection with YuNet (cv::FaceDetectorYN), https://github.com/opencv/opencv_zoo/tree/main/models/face_detection_yunet.

opencv_apps	3.0.0 and later
ROS	ROS One, jazzy, kilted, lyrical and later
OpenCV	OpenCV 4.5.4 or later
Group	Faces, the nodes of which publish ~/faces (FaceArrayStamped)

Usage

# ROS 2
ros2 launch opencv_apps dnn_face_detection.launch.xml image:=/camera/image_raw debug_view:=false
# ROS 1
roslaunch opencv_apps dnn_face_detection.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/tos_faces.mp4
# terminal 1: publish the video as image in a loop
ros2 run image_publisher image_publisher_node tos_faces.mp4 --ros-args -p publish_rate:=10.0 -r image_raw:=image
# terminal 2: run the node
ros2 launch opencv_apps dnn_face_detection.launch.xml image:=image
# terminal 3: view the result
ros2 run rqt_image_view rqt_image_view /dnn_face_detection/image

In ROS 1:

# terminal 1
rosrun image_publisher image_publisher tos_faces.mp4 _publish_rate:=10 __name:=camera
# terminal 2
roslaunch opencv_apps dnn_face_detection.launch image:=camera/image_raw

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
~/face_image	sensor_msgs/msg/Image
~/faces	opencv_apps/msg/FaceArrayStamped
~/image	sensor_msgs/msg/Image

Parameters

See also the common parameters.

Name	Type	Default (range)	Changed at run time	Description
backend	string	“auto”	yes	Backend of cv::dnn: auto, cpu, opencl, opencl_fp16, cuda or cuda_fp16. auto uses CUDA when OpenCV is built with CUDA and a CUDA device is found, and the CPU otherwise.
model	string	“”	yes	Path or URL of the YuNet model (onnx), empty for the default for this OpenCV version. The URL is downloaded to ~/.ros/opencv_apps/models/ at the first time
nms_threshold	double	0.3 (0 - 1)	yes	Threshold of the overlap of the faces to suppress, by non maximum suppression
queue_size	int	3	no, restart the node	Specify queue_size of input image subscribers
score_threshold	double	0.9 (0 - 1)	yes	Threshold of the score to detect the faces
top_k	int	5000 (1 - 100000)	yes	Number of the candidates to keep before non maximum suppression

Source

src/nodelet/dnn_face_detection_nodelet.cpp, launch/dnn_face_detection.launch.xml