I am working on a project that involves a raspberry pi outputting video to tvs. I'd like to have the raspberry pi always output FullHD video.
If it was booted without a display, by default it switched to composite. By adding
force_hdmi_hotplug=1 or something along those lines I got it to always output on HDMI.
However if I power it on without a display, it defaults to a lower resolution (720p?). I could force a specific CEA/DMT mode, but the displays have different refresh rates and progressive/interlaced modes, so I would have to find a mode supported by all.
How would I solve this?
I guess I would have to either:
- configure it to keep the resolution and find the best mode when a tv is plugged
- manually poll available modes, try to find the best, and tell to switch to that. How would I change resolution on command line? I have the X server running a single app without a window manager / desktop environment