info-beamer

Burn-in/Ghosting

I was speaking with our hardware developer and he mentioned ghosting/burn-in as a problem if the screen was going to show the same logo for extended periods of time (several months at a time).
He asked if any action was made to prevent this?
His solution was to show another image (same image but inverted?) for a very shot time (1 ms?) - possible every hour. This would not be seen by any human, but could prevent ghosting.

There’s nothing done against that by default. Isn’t the usual way to avoid this to move the static image from time to time? At least the HDMI displays I know randomly place the “No HDMI input” every 10 seconds or so. Would a similar approach work?

I’m not sure if inverting the output helps. I guess that fully depends on the display specs. If it does and performance doesn’t matter for that single swap from time to time, Lua code could grab the screen output using create_snapshot and feeding that through a shader that inverts colors. It’s essentially:

function node.render()
   -- [rest of the code here]
   if sys.now() % 120 < 0.1 then -- every 2 minutes for 0.1 second
      local output = resource.create_snapshot()
      invert_shader:use() -- doesn't exist, but code for that shader is pretty simple
      output:draw(0, 0, WIDTH, HEIGHT)
      output:dispose()
   end
end