Read a ROS Image Message in Simulink
Start a ROS network.
rosinit
Launching ROS Core... Status before launching ros core :0 result before launching ros core: Microsoft.Management.Serv 2068 Services 0 119,296 K Microsoft.SharePoint.exe 23100 Console 1 342,088 K WindowsTerminal.exe 17292 Console 1 75,132 K Creating Python virtual environment for ros1.Done. Adding required Python packages to virtual environment.Done. Copying include folders.Done. Copying libraries.Done. .....Done in 5.6344 seconds. * Inside getProcessPID function * Process Name: rosmaster - rosmaster --core -p 57282 -w 3 Status before getting PID :0 Result before getting PID :Microsoft.Management.Serv 2068 Services 0 119,296 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,256 K Result: WindowsTerminal.exe 17292 Console 1 86,840 K Status: 0 PID obtained: 17292 Status after getting PID :0 Result after getting PID :Microsoft.Management.Serv 2068 Services 0 119,296 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,256 K * Exiting getProcessPID function * Status after launching ros core :0 result after launching ros core: Microsoft.Management.Serv 2068 Services 0 119,296 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,256 K Status before deleting node :0 Result before deleting node :Microsoft.Management.Serv 2068 Services 0 120,436 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,348 K libmwros1server.exe 13256 Console 1 29,484 K Status after deleting node :0 Result after deleting node :Microsoft.Management.Serv 2068 Services 0 120,404 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,308 K Initializing ROS master on http://172.31.78.36:57282. Initializing global node /matlab_global_node_33098 with NodeURI http://vdi-ah2wsp-001:62664/ and MasterURI http://localhost:57282.
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_33098 with NodeURI http://vdi-ah2wsp-001:62664/ and MasterURI http://localhost:57282. Status before deleting node :0 Result before deleting node :Microsoft.Management.Serv 2068 Services 0 120,400 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,348 K libmwros1server.exe 12612 Console 1 33,256 K Status after deleting node :0 Result after deleting node :Microsoft.Management.Serv 2068 Services 0 120,372 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,308 K Shutting down ROS master on http://172.31.78.36:57282. Status before deleting core :0 Result before deleting core :Microsoft.Management.Serv 2068 Services 0 120,372 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 86,840 K rosmaster.exe 11424 Console 1 4,984 K python.exe 5336 Console 1 4,744 K python.exe 10428 Console 1 30,308 K * Inside killROSProcess function * Status after Process Killed: 0 Result after Process Killed: SUCCESS: Sent termination signal to the process with PID 17292. Status after deleting core :0 Result after deleting core :Microsoft.Management.Serv 2068 Services 0 120,400 K Microsoft.SharePoint.exe 23100 Console 1 341,912 K WindowsTerminal.exe 17292 Console 1 77,008 K * Exiting killROSProcess function *
