Digital signage application. If the TV is on before the device boots the aspect ratio is wrong. [RasPi3+]

Aspect ratio is messed up if the TV is already on before the RasPi boots. This doesn’t seem to be consistent. It’s a docker container running Chromium and some of the react components aren’t scaled properly either. My old boxee box used to do this actually.

I’d imagine it has something to do with the device adjusting to the size of the display on boot?

Has anyone encountered this? Is there any known fixes?

Hi @Medistream as you’re using a Raspberry Pi, you can explicitly set the video output to whatever you want using device variables within the balenaCloud dashboard, and completely avoid any sort of automatic resolution detection.

Take a look at the settings on this page, specifically the settings for hdmi_group and hdmi_mode.

Any of the configuration options detailed here can be applied on the dashboard by prefixing them with BALENA_HOST_CONFIG_. For example, BALENA_HOST_CONFIG_hdmi_mode.

Using these options you should be able to set the output resolution of your device to precisely match that of your TV.