netcam_stream
Use the package to stream network cameras to the ROS network as well as their rectified streams. Additionally give ability to find homography to the plane defined by a calibration pattern.
Usage
To start a stream on an individual camera call the
roslaunch netcam_stream netcam.launch id:=X
where 'X' is the ID of the camera you want to launch. Additionally you can specify launch_user and launch_pass if they are not set in the paramter server.
The created topic will stream at the highest frame rate given by the camera. To manually specify the publisher frame rate (e.g. 15 Hz), use the parameter as follows (the camera will be read at 30 Hz to avoid caching of images)
roslaunch netcam_stream netcam.launch id:=X frame_rate:=15
To launch all cameras, run
roslaunch netcam_stream all_netcams.launch
Calibration
Each camera is associated with a calibration file ('calibration/cam{id}.yaml'), which needs to be located at the base of the file tree for the package.
In order to calibrate the camera with id X, after starting the stream, run
rosrun camera_calibration cameracalibrator.py --size 7x6 --square 0.108 image:=/netcam_stream_X/image_raw camera:=/netcam_stream_X
Remember to move the resulting calibration file to the right place.
After the calibration has finished, commit it using the Commit button.
Aleternatively, Save it. In order to convert it, rename the ost.txt found after uncompressing to ost.ini and parse it
tar -zxvf /tmp/calibrationdata.tar.gz
mv ost.txt ost.ini
rosrun camera_calibration_parsers convert ost.ini camX.yaml
mv camX.yaml ~/catkin_ws/src/netcam_stream/calibration
Homography
Homography can be estimated by launching the associated launch file:
roslaunch netcam_stream homography.launch id:=X
Afterwards, place the calibration board on the plane that the homography transformation needs to be estimated to. Press 'h' to calculate. Repeat until results are satisfied.
This also generates a 'homographyX.yaml' file in the calibration directory.
Install
To install the package, run
catkin_make install
Then navigate to the catkin_ws/install directory and copy the content of lib/network_stream and share/network_stream
roscd && cd ..
sudo cp -r install/lib/netcam_stream/ /opt/ros/indigo/lib
sudo cp -r install/share/netcam_stream/ /opt/ros/indigo/share/