usb_cam_hardware

USB camera driver based on ros_control

Slides from ROS Japan UG #28 (in Japanese)

Nodelet: usb_cam_hardware/USBCamHardware

An USB camera driver which is almost compatible to usb_cam but based on ros_control. Major enhancements over usb_cam are;

• impremented as a nodelet
• supports h264 pixel format (1/10 network usage compared with mjpeg)
• publishes raw packets from the camera (1/10 cpu usage and less latency compared with decoding mjpeg packets in the node)
• accepts 3rd party controllers

Published topics

depends on controllers

Parameters

~video_device (string, default: “/dev/video0”)

~image_width (int, default: 640)

~image_height (int, default: 480)

~pixel_format (string, default: “mjpeg”)

• Possible values are mjpeg, h264, rgb24, yuyv, uyvy

~framerate (int, default: 30)

Controllers

• All topics and parameters are defined in each controller’s namespace
• See example launch files to find how to use controllers

CameraInfoController

publishes camera information syncronized to packets from the camera

Published topics

camera_info (sensor_msgs/CameraInfo)

Parameters

camera_frame_id (string, default: “head_camera”)

camera_info_url (string, default: “”)

camera_name (string, default: “head_camera”)

PacketController

publishes raw packets from the camera as images

Published topics

image (sensor_msgs/Image)

Parameters

image_width (int, default: 640)

image_height (int, default: 480)

encoding (string, default: “bgr8”)

• value of Image::encoding

skip (int, default: 0)

• number of packets skipped after publishment
• useful to throttle network usage

CompressedPacketController

publishes raw packets from the camera as compressed images

Published topics

packet (sensor_msgs/CompressedImage)

Parameters

format (string, default: “jpeg”)

• value of CompressedImage::format

skip (int, default: 0)

• number of packets skipped after publishment
• useful to throttle network usage

MjpegController

decodes mjpeg-compressed packets and publishes decoded images

Published topics

image (sensor_msgs/Image)

H264Controller

decodes h264-compressed packets and publishes decoded images

Published topics

image (sensor_msgs/Image)

RGB24Controller

converts rgb-formatted packets to bgr images and publishes them

Published topics

image (sensor_msgs/Image)

Parameters

image_width (int, default: 640)

image_height (int, default: 480)

UYVYController

converts uyvy-formatted packets to bgr images and publishes them

Published topics

image (sensor_msgs/Image)

Parameters

image_width (int, default: 640)

image_height (int, default: 480)

YUYVController

converts yuyv-formatted packets to bgr images and publishes them

Published topics

image (sensor_msgs/Image)

Parameters

image_width (int, default: 640)

image_height (int, default: 480)

Related ROS packages

codec_image_transport

• for subscriber-side decoding of h264 packets published by the CompressedPacketController