Read A ROS Image Message In Simulink

Start a ROS network.

rosinit

Launching ROS Core...
....Done in 4.236 seconds.
Initializing ROS master on http://172.21.16.85:53224.
Initializing global node /matlab_global_node_92597 with NodeURI http://ah-avijayar:61421/ and MasterURI http://localhost:53224.

Load sample messages to send including a sample image message, img. Create a publisher to send a ROS Image message on the '/image_test' topic. Specify the message type as '/sensor_msgs/Image'. Send the image message.

imgcell = load('imgdata.mat','img');
img = imgcell.img;
pub = rospublisher('/image_test','sensor_msgs/Image');
send(pub,img)

Open the Simulink® model for subscribing to the ROS message and reading in the image from the ROS.

Ensure that the Subscribe block is subscribing to the '/image_test' topic. Under Simulation tab, select ROS Toolbox > Variable Size Messages. Notice that the Use default limits for this message type is clear. Then, in the Maximum length column, verify that the data property of the sensor_msgs/Image message has a value greater than the number of pixels in the image (921600). Run the model.

open_system('read_image_example_model.slx')

Run the model. The Video Viewer shows the sample image.

Stop the simulation and shut down the ROS network.

rosshutdown

Shutting down global node /matlab_global_node_92597 with NodeURI http://ah-avijayar:61421/ and MasterURI http://localhost:53224.
Shutting down ROS master on http://172.21.16.85:53224.