[Help] Multiple 1080p h.264 stream decoding hardware requirements?

Long story short (and a lot of stuff I can't really say), but I need to figure out a way to decode up to 16 1080p, h.264 streams (from digital cameras, such as security cameras). Does anyone know how much cpu horsepower it would require to be able to handle that? I have a suspicion that it could be handled via software decoding with a relatively high end xeon or something. Using gpu acceleration, or hardware decoding would be optimal, but getting that to work would likely prove problematic. Does anyone have any experience with something like this?

EDIT: Forgot to mention.
I am basically going to be using the same codecs as vlc, so I tried playing back as many h.264 videos as possible. With an i5-4430, it was able to effortlessly play back 4 videos simultaneously with cpu usage around 25%. But when I tried to do more than that, 5 videos, vlc freaked out, and wouldn't play back smoothly, blocking, stuttering, etc on all 5 videos. I don't know if there is a setting in vlc or something that could be causing this (I was thinking that some of the effect settings or maybe the hardware acceleration) could not handle that many instances running at a time and flipped its lid. I'm really hoping that someone more knowledgeable than me will be able to chime in.

Probably just get something with that many cores or threads

maybe a used dual Xeon Set up

but I've really no idea, don't listen to me

so, are you decoding -> mixing -> reencoding?

Do you just need to display live feeds?

Are you saving the streamed video?

Are you re-streaming the video feeds?

How are the feeds coming into the computer? Etho?

That is basically what I was thinking. 1 thread per stream should leave enough overhead for everything else that needs to be running (since I don't think that it will take more than a single thread maxed out to decode it in software).

Just decoding. Streams coming in and need to be shown on the screen. All of the saving, and whatnot will be handled by a different computer, so I am not really worried about that.

EDIT: As for how the streams are coming it, it is a bit complicated. But basically, this workstation will be receiving the streams as requested from a central server, if I am not mistaken.

So you just need to display live feeds coming in over ethernet?

More or less. As you can tell, I haven't really done any irl testing of this. Want to get it laid out before I go forward with anything as far as implementation.

Quick search reveals vlc has gpu acceleration option.

https://wiki.videolan.org/VLC_GPU_Decoding/

Yeah, I know that much. I just don't know how easily I will be able to take advantage of that in my specific application. So I would like to know how much cpu horsepower would be required if I can't get it working effectively, or how much gpu horsepower it would require if I did get it working.

well, that's a tricky question... there are so many different things that could bottle neck you. IMHO, you'll just have to throw more power at it till it works.

Which is exactly what I am hoping to avoid. I am hoping that someone will be able to drop some knowledge on me here. I've seen stranger questions answered around here.

You may be able to get a good answer on vlc forums....

Possible, but I don't have an account there yet. Call me lazy.