ximea_camera

1) License

Copyright 2015

• Abdelhamid El-Bably (University of Waterloo) [ahelbably@uwaterloo.ca]
• Arun Das (University of Waterloo) [adas@uwaterloo.ca]
• Michael Tribou (University of Waterloo) [mjtribou@uwaterloo.ca]
• Simon Schulz (University of Bielefeld) [sschulz@techfak.uni-bielefeld.de]

All rights reserved.

This software is distributed under the BSD three-clause license.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of the University of Waterloo nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

2) Dependencies

This software requires the Ximea Linux Software Package. See http://www.ximea.com/support/wiki/apis/XIMEA_Linux_Software_Package for details.

3) Basic Usage

This software provides ROS drivers for the ximea xiQ USB 3.0 Cameras. This driver supports image acquisition from an arbitrary number of cameras, so long as there is sufficient bandwidth on the USB 3.0 bus to perform the data transfer. In order to operate the cameras, the serial numbers of the devices must be known.

1. create a configuration file for each camera. The configuration file should be kept in the /config folder. A configuration file will look as follows:

serial_no: 32301951
cam_name: "camera1"
yaml_url: "package://mcptam/calibrations/camera1.yaml"
exposure_time: 30000
rect_left: 200
rect_top: 200
rect_height: 600
rect_width: 900
allocated_bandwidth : 1.0
image_data_format: "XI_MONO8"

• serial_no refers to the serial number of the camera
• cam_name is the name you wish to give to the camera
• yaml_url is the location of the calibration information file, which is used by the camera info manager to publish the calibration parameters
• exposure_time refers to the image exposure time in microseconds
• rect_left, rect_top, rect_height, rect_width are used to set the image region of interest (ROI). See the Ximea xiQ API for more information (http://www.ximea.com/support/wiki/apis/XiAPI_Manual).
• allocated_bandwidth refers to the usb3 bandwidth fraction you want to assign to this camera (use 1.0 if you have one cam and 0.5 for two etc)
• use_cam_timestamp enabling this (=true) will use the camera timestamp feature and a correction offest to reflect system time (EXPERIMENTAL)
• image_data_format: sets the data format for the image. Currently, formats XI_MONO16, XI_RGB24, XI_RGB32, XI_RAW8, XI_RAW16, and XI_MONO8 are supported

2. Create a launch file for your camera configuration. A typical launch file will look as follows:

<launch>
<!-- Camera Node -->
<node name="ximea" pkg="ximea_camera" type="ximea_camera_node" output="screen" >
  <param name="frame_rate" type="int" value="60" />

  <rosparam param="camera_param_file_paths" subst_value="true">[$(find ximea_camera)/config/ximea1.yaml, $(find ximea_camera)/config/ximea2.yaml]</rosparam>

</node>

</launch>

The main parameters of interest are the frame rate and the file paths.

• frame_rate corresponds to the frame rate for all of the cameras in the group.
• camera_param_file_paths is a list of file names corresponding to the configuration files made for each camera in step 1. For a single camera setup, the camera_param_file_paths parameter would look something like:

<rosparam param="camera_param_file_paths" subst_value="true">[$(find ximea_camera)/config/ximea1.yaml]</rosparam>

while a three camera setup would have a list containing the file names for the configuration files of all three cameras, separated by commas:

<rosparam param="camera_param_file_paths" subst_value="true">[$(find ximea_camera)/config/ximea1.yaml, $(find ximea_camera)/config/ximea2.yaml, $(find ximea_camera)/config/ximea3.yaml]</rosparam>

3. You should now be able to plug in the cameras and launch the file created in step 2.

4) Published Topics

Each set of published topics will be under the namespace corresponding to the camera name. Each camera will publish:

• /camera_info, which is of ROS message type sensor_msgs/CameraInfo. This message carries all of the camera specific calibration information.

• /image_raw/, which of of ROS message type sensor_msgs/Image. This message carries the image data.