khalaf90 / ros-camera-gui

Camera GUI in ROS with Qt5/C++

ros-camera-gui

Camera GUI in ROS with Qt5/C++

For user:

1- Install Qt5:

sudo apt-get update

sudo apt-get install qt5-default

sudo apt-get install qtcreator

2- Download the support packages:

sudo apt-get install ros-kinetic-qt-create

sudo apt-get install ros-kinetic-qt-build

3- Steps to rebuild your workspace:

• Copy the folder 'qtros' to your catkin workspace src folder.
• check in the qnode.cpp the topic name you would like to display, currently the topics are: /ir/flir_tau2/image1 and /ir/flir_tau2/image2
• check in the main_window.cpp the path, where the snapshot pictures will be saved, currently the path is: /media/ubuntu/demo/ . You can choose in code in which image format (.jpg or .png) the picture should be saved
• build the workspace using catkin_make
• source the workspace source devel/setup.bash
• run the package using: - rosrun qtros qtros or run the qtros app located in /devel/lib/qtros/ (using terminal: ./qtros)
• When the package is running:
  • the first tab is for ROS communications: you will get the ROS Master Url when roscore is running and ROS IP using ifconfig.
  • suppose that the camera node and gui node are running on different computers, to establish the ROS network:
    • in the computer where camera node and roscore is running: navigate to .bashrc file gedit .bashrc
    • add export ROS_IP=<gui node Computer IP> at the end
    • you may check how to establish ros network at
  • the second and third tabs are for displaying the camera pictures and offering the user following services: start, stop and snapshot

Attention: This GUI is designed to display 16-bit grayscale images from thermal camera, if you want to modify it, follow `for developer` instructions

For developer:

1- Install latest Qt version from, step-by-step installation guide could be found at

2- Go where Qt is installed ~/Qt5.12.2/Tools/QtCreator/bin and open it using terminal ./qtcreator

3- To import the GUI project to QtCreator, The steps are:

• Click “File->Open File or Project”
• Load the project using its “CMakeLists.txt” in qtros package folder
• Go to Projects and browse in build directory to the build folder generated after catkin_make and choose it:

Practical issues:

• • Image processing:
  • Software Architecture:

The ROS image message is converted to an OpenCV image, the obtained image is again converted to a Qt image.

Translating this in code means: when you do image processing adjust myCallback function in qnode.cpp and displayMat function in main_window.cpp :

• For OpenCV: try to avoid for loop (loop over an image pixel-by-pixel is slow)
• For Qt: available Qimage formats can be found at

• • Update .ui file:
  • when you modify main_window.ui (Add new buttons, change label size ...etc), you need to update ui_main_window.h, the steps are:
    • save your modifications Ctrl+S
    • delete main_window.hpp in src/qtros/include/qtros/main_window.hpp and delete the build and devel folders generated after catkin_make
    • catkin_make and ignore the error which will appear
    • go to gui_ws/build/qtros and copy the new generated main_window.hpp and paste it in src/qtros/include/qtros/
    • catkin_make
    • run the package and you will see now your modifications