If you look at the growth of controllers and software over last few years. Christmas lighting with pixels is in it's infancy. Currently to manage large numbers of pixels, we are synchronizing multiple PI's. This is limited to 16 PI's at 64K channels or about 2048 universes. Yet if you look at the humble PI, it can output full HD at 1080p, which is about 6 million channels or 12K universes. It seems that the natural progression is a video to pixel converter.
A video to pixel converter would also provide an easy path to using video, since you could move up to 60 hertz or faster frame rates. This would allow most video to played without modification. Also, it is pretty much crazy to sequence every pixel, so we are moving to pixel generated sequences. With that in mind a faster frame rate, would provide smoother effects. I know, because I wanted to curtain's last year on my icicles and the effect was too slow for the song.
Looking at the cost for Ethernet components (wire/switches) and the fact that most controllers already support ACN1.31, Ethernet is the natural choice in this progression to distribute the pixel data. Also, the components to build multiple Ethernet ports is inexpensive.
I would propose that we standardize the mapping of pixels to ACN1.31 for multiple video resolutions. Keep in mind as we go up in resolution, we will need more output ports or move eventually to 1G. For the beginning of this transition, I would recommend that we start with 640x480 resolution. So I divided this up a video frame into four columns of 160x480 pixels. Since 100M Ethernet is only fast enough to output a line every other line, two ports can be used for a column, or you can support two modes. Interlaced, where you alternate the output of odd/even lines, or progressive where only the even lines are output.
ooo ooo ooo ooo Even line
xxx xxx xxx xxx Odd line
ooo ooo ooo ooo Even line
xxx xxx xxx xxx Odd line
So, i have built a single port bridge for testing, but it does not make sense to move forward without support of the software community. My intention is to build a DVI to four port converter, using off the shelf modules. The Ethernet ports are $10 each, a $16 FPGA card, and a custom card with the $9 DVI receiver chip. As with all of my designs the boards and firmware would be open sourced on www.diychristmas.org.
https://www.youtube.com/watch?v=c1xbA51amWYRon
