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ROS + RaspberryPi Camera Module #3: An alternative package for publishing images from Raspi

08 Sep 2017 » ros, raspberrypi

Streaming images from Raspi over Network: video_stream_opencv

For this particular project, I originally started off by using the raspicam_node developed by Ubiquitous Robotics, which handles JPEG compression on the RaspberryPi leveraging the videocore found locally. The publish rate tested on the Raspi was ~30hz, but over the network the performance degrades and is unable to maintain a reasonable fps unless the dimensions are set to around 640x480. There is also another ROS package video_stream_opencv [1] that works on the Raspi pretty much out of the box and provides ~25hz+ over the network as well with dimensions set at 640x480. The good thing with this package is that we can simply start by installing using sudo apt-get install ros-kinetic-video-stream-opencv and then finish the installation process by building the package.

After installing and building the package the webcam.launch file can be launched which will publish the following topics.


Checking the publishing rate over the network from the master computer results in satisfactory results.

$ rostopic hz /webcam/image_raw/compressed
subscribed to [/webcam/image_raw/compressed]
average rate: 31.105
    min: 0.020s max: 0.040s std dev: 0.00453s window: 27
average rate: 29.865
    min: 0.004s max: 0.153s std dev: 0.01801s window: 55
average rate: 29.978
    min: 0.000s max: 0.167s std dev: 0.02493s window: 86


  1. http://wiki.ros.org/video_stream_opencv