What excatly do you want to add?
If you want to add more protocols like miniDMX you have to add it to AtmoWin, not this plugin since the plugin only delivers the "Screenshots" to AtmoWin.
AtmoWin is open source (but mostly german).
Atmowin is limited to 5 channels by default with the atmolight protocol, would like to send it directly to a serial device and let the plugin calculate the zones en average colors.
With digital leds this is easy and XBMC already has the DFatmo plugin which does something similar, also want to add features like when it's paused default to a specified color.
Currently have a 256 channel ambilight setup working which works pretty good with movies/games but integrated into mediaportal would of course be nice
The source of Atmowin is a bit messy and doesn't allow for easy modifications, looks like a lot of different people worked on it and as a result the code is inconsistent but that's just my first impression.
I've played a short time with the Atmolight process plugin, but figured I dont need it. It would be a great addition, if it allowed to change the AtmoWin parameters without having to close MediaPortal, similar to how the VLC Filter does.
The old 4 channel version did work, the new one doesn't list support for windows anymore.
But i don't see why it shouldn't be supported, maybe you should ask carsten directly.
But in my eyes 99€ just for an 8 channel board is too mch.
With a SEDU Board you can control up to 64 channels, and the price (with the more expensive leds included) should be simmilar.
Besides the board you need special LED Stripes with individual controllable LEDs and a power supply (or you can wire your ATX-power to the LEDs).
I guess you would pay around (just a quick summary):
40€ for the board
84€ for 2m led stripes (42€ for each meter of the led stripes, each meter has 32 individual rgb leds). maybe you need more, depends on your TV size.
15€ for a power supply - 20W/5V
17€ shipping
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156€ :/