Device with 4 Displays and 4 Cameras


#1

Hi!, we’re starting the development of a device that needs 4 cameras and 4 displays. For a first prototype we’ve been thinking on using a ultra96 board with displays connected by eDP and the cameras by USB3.0. Ideally the 4 displays should be independent, but we can have two independent and two sharing the same video source.

The idea would be to validate the displays and cameras, and then consider if we develop a custom interface board for using MIPI and avoid eDP and USB3.0.

What do you think?, could the ultra96 or another 96board compliant evb be useful for that purpose?

Thanks!

DGS


#2

The mDP (“m” for “mini”, not “e” for “embedded”) would seem to be a compelling feature on the ultra96. The only other board that would come close to your requirements may be the dragonboard 820c, which as I understand it, may be capable of independently driving at most, 4 displays (1xHDMI + 2xDSI + 1xMiracast) – you could of course, mirror any of the outputs amongst any number of displays.

Just make sure you know what you’re getting into with any of the boards. I don’t have any first hand knowledge of the ultra96, or what kind of problems you may end up facing trying to get multiple monitors working on it.

Does it actually have to be one board that handles all of those displays directly? Or could your project be adapted to running multiple SBC’s that are networked together? For instance, some cheap board like a pi0 might give you a $5 option for adding a virtually unlimited number of displays.


#3

Not sure if the 820 could handle both dual DSI and HDMI in parallel, but either way it would be messy, assuming you want to drive 4 identical panels.

You may want to look into a DSI splitter IC for a cleaner solution:

http://www.latticesemi.com/Products/DesignSoftwareAndIP/IntellectualProperty/IPCore/IPCores04/1Inputto2OutputMIPIDSIDisplaySplitterBridge

But then 4 camera’s? I think it handles only up to 3. Again, the FPGA guys have some nice IP for you:

https://www.latticesemi.com/en/Products/DesignSoftwareAndIP/IntellectualProperty/IPCore/IPCores04/4Inputto1OutputMIPICSI2CameraAggregatorBridge


#4

Great idea!, for this first prototype using several pi0 could do the trick. Thanks for the suggestion!


#5

Hi!, I will check if they can handle dual DSI and HDMI, I know that in some of these boards they share video source and one can not use them independently.
Regarding the splitter and “joiner”, thanks for the suggestion. I’d been reviewing Omnivision OV680 to join 2x1-lane into 1x2-lane.
Thanks again!


#6

Hi again,

I’ve been reading this info, and I’m not sure if using this FPGA IP solution will help us in our use case. In the case of the cameras, they aggregate 4 input to 1 output, so the host will consider it a single source. What we’d need is 4 cameras to be managed by the host as 4 independent video sources, since we need to independently process each video.

The same applies for the displays, since we need it to be managed as independent displays (or 2 independent + 2 mirrored).

Thanks!


#7

He was talking about USB3 cameras. There is no limit to the number of UVC cameras you can plug in, except for the USB bandwidth.


#8

Oh yes I see, USB camera’s. Or you mix and match those with 2 CSI camera’s. But anyway if you would have 1 aggregated input, you could just slice it in software, right?

I never worked with those IC’s BTW. I wonder how you adress two displays via a single interface. Perhaps as a double-width or height display or with alternating frames?