Camera setup on RPi4
This assumes that you'll be using the Raspberry Pi Camera Module, which can easily hooked on the board using the LVDS connector. Further more information about how to connect it, could be found at Installing a Raspberry Pi camera
With the camera installed, you'll need to enable it by editing /boot/config.txt file (if you're booting an AGL image over a sd-card it will be there by default, otherwise -- in case of doing netboot, you'll have to create manually) and add the following entry:
## start_x ## Set to "1" to enable the camera module. ## ## Enabling the camera requires gpu_mem option to be specified with a value ## of at least 128. ## ## Default 0 ## start_x=1
And reboot your device. Afterwards, after logging it, make sure that you have the /dev/video0 device created. You could also use v4l2-ctl to verify that is indeed usable as a capture device:
$ v4l2-ctl -d /dev/video0 --all
In order to test out video playback, use the following gstreamer pipeline:
$ gst-launch-1.0 v4l2src device=/dev/video0 ! \ video/x-raw,width=640,height=480 ! waylandsink fullscreen=true
Alternatively, using camera-gstreamer application could might be another possibility, but you'll have to build it yourself and add it in the image.
This includes an example on how to create a xdg-toplevel surface and create a gstreamer pipeline, instead of relaying on waylandsink to create one for you, in a programmatic fashion.
Display setup on RPi4
This assumes that you'll be using the Raspberry Pi 7'' display. Installation can be found at Rpi Display page.
If booting over the network, the dtb should already contain the ft5406 dtb, while booting over sd-card the following show be in the /boot/config.txt file:
Once the board boots up, you should get a rainbow like effect and afterwards booting up would display debug scrolling over. You'll need to adjust the orientation as the 800x480 is in portrait. Edit /etc/xdg/weston/weston.ini and add a new output entry, like the following:
[output] name=DSI-1 transform=90
Note that for the Qt platform, the homescreen application, together with the other demo applications, is tailored specifically for a 1080p display and it will display incorrectly on such a smaller display.
Testing out video camera without a real device
While the above requires having a real video camera device, one can use out the vivid module to try out your custom application or just testing out camera functionality in AGL.
You should normally have the module present, not loaded, for either rpi4 or for h3ulcb boards. Load the module, like in the following command:
modprobe vivid allocators=0x1
Have a look at the kernel ring buffer to see what capture devices are created and use as source:
$ gst-launch-1.0 v4l2src device=/dev/videoXX ! \ video/x-raw,width=640,height=480 ! waylandsink fullscreen=true
making sure to replace /dev/videoXX with correct capture device. You can check that easily using the v4l2-ctl mentioned above.
Note that using camera-gstreamer will attempt to find the first available capture device, so if you happen to have to another one before the one created by this module it might not work. You can bypass that, by just making a symlink from /dev/videoXX to /dev/video0 to make first available capture device.