So, for today, a holiday weekend, raining all weekend... sigh. So I deiced to work this. I got rid of the UNO, and just went with the PI on GPIO 18. Re-followed Dr.Z's video just for reminder things. I did grab a new HDMI capture device, one that was rated pretty good from others here.
With dropping the resolution down to 720 X 480, the lag is very little but, still there. A lot less than I could get with the UNO.
Had to drop the brightness down to 80% or red images (or any very bright color) would be a flicker/flashing fest. I am wondering why I need to do this ? I got a 5v 30a power supply, way over powered for what I actually need. Is the flicker due to power issues AKA lack of power ?
I used to have a 5v 10a PS doing this before (same amount of LEDs, with the old JAVA based Hyperion app), never a single flicker. I figured bigger supply would give better results... I guess not.
I'll have to play with it for a little bit but, looking good so far...