GTK demo launcher

This article provides information on the Demo Launcher application. The Demo Launcher starts by default with the Starter Package. This application is written in pythonTM3[1] and uses GTK[2] to display the user interface. A touchscreen is required to control the application.


1 Main menu[edit]

The main menu is composed of six demonstrations:

Main menu
Netdata perf monitor Gives information in how to connect to the board through Ethernet or Wi-Fi® (if available) in order to connect to netdata
Camera preview Displays the preview camera
Video playback Displays the video playback
Artificial intelligence Handwriting character recognition (using Arm® Cortex®-M4 firmware)
3D GPU Displays a rotating 3D cube
Bluetooth® speaker Allows the connection to a Bluetooth®headset


To exit from this window, tap on the cross in the top-right corner. To launch it again, tap or click on the Weston icon launcher with nine blue squares.

2 Netdata perf monitor[edit]

Netdata is a tool which starts on boot and provides all monitoring information on a web page accessible using the board IP address. This window helps with the network connection and gets the board netdata information.

If an Ethernet network is available, the URL to connect to netdata is displayed.
If wireless network is available, a cursor button is displayed to enable hotspot Wi-Fi®.
If Wi-Fi® hotspot is enabled with default configuration, two QR-codes are displayed on screen:

  • The first one gives the Wi-Fi® hotspot connection parameters
  • The second one provides the URL to connect to netdata

To exit from this window, double tap anywhere on the screen.

3 Camera preview[edit]

Display the preview from /dev/video0.

  • On STM32MP157C-DKX boards, a USB webcam can be used
  • On STM32MP157C-EVX boards, either a MB1379 camera daughter board or a USB webcam can be used.

Ensure that the webcam is compatible with Linux®.

The available actions to control the camera preview are:

  • First tap: as preview is composed by Wayland, the first tap has to be done outside the camera preview window to recover the GTK focus.
  • Simple tap: pause-resume the camera preview.
  • Double tap: double tap anywhere on the screen to exit from this window.

More information on V4L2 is available in V4L2 camera overview and how is managed the display in Wayland_Weston_overview.

4 Video playback[edit]

Video Playback

Here are the available actions to control the video playback:

  • First tap: as video is composed by Wayland, the first tap has to be done outside the video playback window to recover the GTK focus
  • Double tap: double tap anywhere on the screen to exit from this window.

More information on Gstreamer is available in GStreamer_overview and how is managed the display in Wayland_Weston_overview.

5 Artificial Intelligence[edit]

Artificial Intelligence

This is a handwriting character recognition application:
1) Draw a character on the screen. It is then analysed by the firmware running on Arm® Cortex®-M4 side.
2) If the character is recognized, it is displayed on the left. If it is not, a question mark is displayed.
3) When the recognized character is associated with an application, the application is launched:

  • A: to launch audio playback
  • C: to launch camera preview
  • P: to display a picture
  • V: to launch a video playback
  • S: to stop the launched application
  • Q: to exit from the Artificial Intelligence demo.
Warning white.png Warning
It is possible to start several instances of the same application (for example three audio playbacks at the same time). This is not recommended

.

6 3D GPU[edit]

3D GPU

A cube rotates on the screen to demonstrate streaming video.

The available actions to control the video playback are:

  • Continuous tap : a continuous press on screen will drag the cube.
  • Double tap: exit from this window, double tap anywhere on the screen.

More information on the GPU is available in Vivante_GCNANO_GPU_overview and how is managed the display in Wayland_Weston_overview.

7 Bluetooth® speaker[edit]

Bluetooth speaker

This application is able to discover Bluetooth® devices, and pair/connect to them. If an audio capable device is connected, the message The audio BT device <your device> is connected is displayed.

First use:
1) Tap on start scan button: a scan of discoverable devices is done during 15 seconds. The scroll bar progression is displayed.
2) Select the device in the list, and tap on connect.

If the device is already connected, the "disconnect button is displayed instead.

To exit from this window, double tap anywhere on the screen.
More information on Bluetooth® is available in Bluetooth_overview.

8 Info menu[edit]

Click on the "i" icon on the right of the screen. It displays the menu describing how to use the demos. To exit from this window, double tap anywhere on the screen.

9 How to add a new demo application[edit]

Add a new demo application is possible with ecosystem release ≥ v1.2.0 .

The GTK demo launcher is scalable which means new application can be added. The GTK demo launcher uses specific yaml files to automatically detect which application to display.
An application on GTK demo launcher:

  • is described by a yaml file which gives the application details e.g.: information to display, how to launch it, ...
  • is indexed to be displayed in specific order,
  • can be enabled for a specific STM32MPU device,
  • can be launched in the presence of specific devices.
  • must be launched on full screen
  • must manage the QUIT/EXIT


For scalability of an application is managed by:

  • an indexed yaml file (meaning that file is prefixed by a number which indicate the order to display the application on GTK demo launcher)
  • a sub-tree which contains any pictures and any mandatory script to run application.

Sub-tree example for video application:

 /usr/local/demo/application/
 ├── 02-video.yaml
 └── video
     ├── bin
     │   └── launch_video.sh
     └── pictures
         └── Video_playback_logo.png
Info white.png Information
For usage of gstreamer graph in case of camera preview, video playback, ... an application are available.

touch-event-gtk-player: permit to play a gstreamer graph and manage play/pause event via a simple click/touch and manage quit/exit of playback via double click/touch.
/usr/local/demo/bin/touch-event-gtk-player --graph "<gstreamer graph>"

9.1 YAML application format[edit]

Below is given an example of format used to describe an application.

 Application:
    Name: <name of application>
    Description:  <description of application>
    Icon: <icon of application>
    Type: <script|python>
    Board:
        |<List>or  <|NotList>:  <all> or <list of chip>
    Script:
        Exist:
            <File|Command>: <file or command to verify}
            Msg_false: Message to display if  <File> or <Command> are not present
        Start:  <script or application to launch application>
    Python:
        Exist:
            <File|Command>: <file or command to verify>
            Msg_false: <Message to display if <File|Command> are not true
        Module: <Python module name to load>
    Action:
        button_release_event: <python_start|script_management>
        button_press_event: highlight_eventBox

Parameters description:

Name
application name displayed on GTK demo launcher.
Description
application description displayed on GTK demo launcher.
Icon
application icon to be displayed on GTK demo launcher.
Board
List: list of STM32MPU devices which are compatible with the application.
NotList: List of STM32MPU devices which are not compatible with the application.
Type
Types of script which can be used to launch the application.
Available types:
  • script : shell script or application (without parameters) to use for launching application.
  • python: Python script to load for launching application.
Both types have a specific declaration available: script", "python".
Script
This section describes the script (shell or application) used to launch application.
This section has 3 sub-sections:
  • Exist: list requirements that must be verified before launching start command
  • Start: identify the command that starts the application
Exist
  • File: to verify the presence of a specific file. If files are present then the application can be launched with Start
  • Command: to check if command to execute exist. If "Ok" is returned then application can be launched with Start
Example
        Exist:
            File: /dev/video0
            Msg_false: Webcam is not connected,
                    /dev/video0 doesn't exist
Python
This section describes the PythonTMscript to load to access the application functionality.
The PythonTM script must have the function create_subdialogwindow(<parent window>).
This section sub-divided into several sub-sections
  • Exist: verifies the requirements before launching the start command
  • Module: PythonTM module name to load, it corresponds to the path and script name.
Example
     for a path application/netdata/netdata.py,  module name must be application.netdata.netdata
     Module: application.netdata.netdata
'Tips: you need to add an empty file name "__init__.py" on each sub-directory to be able to launch the PythonTM module
Exist
  • File: checks the presence of specific files. If the files are present the application can be launched with Start
  • Command: command to execute, if "OK" is returned the application can be launched with Start
Example
        Exist:
            Command: hciconfig hci0 up
            Msg_false: Please connect a Bluetooth<sup>®</sup> controller on the board

9.2 File Tree[edit]

Example of sub-tree used by GTK demo launcher.

/usr/local/demo/application/
 ├── 000-netdata.yaml
 ├── 010-camera.yaml
 ├── 020-video.yaml
 ├── 030-3d_cube.yaml
 ├── 040-m4_ai.yaml
 ├── 060-bluetooth_audio_output.yaml
 ├── 3d_cube
 │   ├── bin
 │   │   └── launch_cube_3D.sh
 │   └── pictures
 │       └── ST153_cube_purple.png
 ├── bluetooth
 │   ├── bluetooth_audio.py
 │   ├── __init__.py
 │   ├── pictures
 │   │   └── ST11012_bluetooth_speaker_light_green.png
 │   └── wrap_blctl.py
 ├── camera
 │   ├── bin
 │   │   └── launch_camera_preview.sh
 │   ├── pictures
 │   │   └── ST1077_webcam_dark_blue.png
 │   └── shaders
 │       └── edge_InvertLuma.fs
 ├── __init__.py
 ├── m4_ai
 │   ├── bin
 │   │   └── launch_AI.sh
 │   └── pictures
 │       └── ST7079_AI_neural_pink.png
 ├── netdata
 │   ├── bin
 │   │   └── build_qrcode.sh
 │   ├── __init__.py
 │   ├── netdata.py
 │   └── pictures
 │       └── netdata-icon-192x192.png
 └── video
     ├── bin
     │   └── launch_video.sh
     └── pictures
         └── Video_playback_logo.png

9.3 Examples of yaml application file[edit]

9.3.1 with Script, verification of presence of device and board support[edit]

Application:
    Name: 3D Pict
    Description: GPU with picture
    Icon: application/3d_cube/pictures/ST153_cube_purple.png
    Board:
        NotList: stm32mp151
    Type: script
    Script:
        Exist:
            File: /dev/galcore
            Msg_false: No GPU capabilities to run 3D GPU demo
        Start: application/3d_cube/bin/launch_cube_3D.sh
    Action:
        button_release_event: script_management
        button_press_event: highlight_eventBox

9.3.2 with Script and verification of presence of device[edit]

Application:
    Name: Camera
    Description: shader
    Icon: application/camera/pictures/ST1077_webcam_dark_blue.png
    Board:
        List: all
    Type: script
    Script:
        Exist:
            File: /dev/video0
            Msg_false: Webcam is not connected,
                    /dev/video0 doesn't exist
        Start: application/camera/bin/launch_camera_shader.sh
    Action:
        button_release_event: script_management
        button_press_event: highlight_eventBox

9.3.3 with PythonTM and verification via command[edit]

Application:
    Name: Bluetooth
    Description: speaker
    Icon: application/bluetooth/pictures/ST11012_bluetooth_speaker_light_green.png
    Type: Python
    Board:
        List: stm32mp157 stm32mp153
    Python:
        Exist:
            Command: hciconfig hci0 up
            Msg_false: Please connect a Bluetooth<sup>®</sup> controller on the board
        Module: application.bluetooth.bluetooth_audio
    Action:
        button_release_event: python_start
        button_press_event: highlight_eventBox

9.4 Example of recipe to add an application[edit]

With ecosystem release ≥ v1.2.0 is delivered an example of recipe useful to add an application (demo-application-3d-cube) in the GTK demo launcher. It is available at this location:

meta-st-openstlinux/recipes-samples/demo-application/demo-application-3d-cube.bb

When creating the recipe, some attention points must be checked:

  • Put a correct index for yaml file name which determine the order to display the application (see example below)
  • Install all the appropriate application sub-tree in /usr/local/demo/application,
  • The application launched must be launched on full screen and must manage QUIT/EXIT.
  • Set the correct execution permission on the script file,
chmod 0755 <script name>
  • Sub-tree example for the demo-application-3d-cube:
/usr/local/demo/application
├── 100-3d-cube.yaml
├── 101-3d-cube-shader.yaml
├── 105-3d-cube-picture-shader.yaml
├── 110-3d-cube-video.yaml
├── 111-3d-cube-video-shader.yaml
├── 115-3d_cube_camera.yaml
├── 116-3d_cube_camera_shader.yaml
├── 120-3d-cube-pictures-shader.yaml
└── 3d-cube-extra
    ├── bin
    │   ├── launch_cube_3D_1_picture_shader.sh
    │   ├── launch_cube_3D_3_pictures_shader.sh
    │   ├── launch_cube_3D_camera.sh
    │   ├── launch_cube_3D_camera_shader.sh
    │   ├── launch_cube_3D_color.sh
    │   ├── launch_cube_3D_color_shader.sh
    │   ├── launch_cube_3D_video.sh
    │   └── launch_cube_3D_video_shader.sh
    └── pictures
        └── ST153_cube_purple.png
  • Associated recipe:
DESCRIPTION = "Adds support of 3d Cube application on Demo Launcher"
HOMEPAGE = "wiki.st.com"
LICENSE = "BSD-3-Clause"
LIC_FILES_CHKSUM = "file://${COREBASE}/meta/files/common-licenses/BSD-3-Clause;md5=550794465ba0ec5312d6919e203a55f9"

DEPENDS = "weston-cube demo-launcher"

SRC_URI = " \
    file://100-3d-cube.yaml \
    file://101-3d-cube-shader.yaml \
    file://105-3d-cube-picture-shader.yaml \
    file://110-3d-cube-video.yaml \
    file://111-3d-cube-video-shader.yaml \
    file://115-3d_cube_camera.yaml \
    file://116-3d_cube_camera_shader.yaml \
    file://120-3d-cube-pictures-shader.yaml \
    file://launch_cube_3D_1_picture_shader.sh \
    file://launch_cube_3D_3_pictures_shader.sh \
    file://launch_cube_3D_camera.sh \
    file://launch_cube_3D_camera_shader.sh \
    file://launch_cube_3D_color.sh \
    file://launch_cube_3D_color_shader.sh \
    file://launch_cube_3D_video.sh \
    file://launch_cube_3D_video_shader.sh \
    file://ST153_cube_purple.png \
    "

do_configure[noexec] = "1"
do_compile[noexec] = "1"

do_install() {
    install -d ${D}${prefix}/local/demo/application/3d-cube-extra/bin
    install -d ${D}${prefix}/local/demo/application/3d-cube-extra/pictures

    # install yaml file
    install -m 0644 ${WORKDIR}/*.yaml ${D}${prefix}/local/demo/application/
    # install bin
    install -m 0755 ${WORKDIR}/*.sh ${D}${prefix}/local/demo/application/3d-cube-extra/bin
    # install pictures
    install -m 0644 ${WORKDIR}/*.png ${D}${prefix}/local/demo/application/3d-cube-extra/pictures
}

FILES_${PN} += "${prefix}/local/demo/application/"

9.5 How to install demo application via packages[edit]

If the GTK demo launcher is not yet installed

 dpkg -l | grep demo-launcher
 ii  demo-launcher          1.0-r0    armhf        Python script which ls-

It can be installed with the following command:

apt-get update
apt-get install demo-launcher

To add 3D application:

apt-get install demo-application-3d-cube

10 References[edit]