I'm copy-pasting on mobile, so sorry about quoting differently.  Making something like the PBB project has been a major dream of mine for some time.  I'm combining how-to-do-it with whether-to-do-it below, might be good to separate those topics.

Jim Bell said:

built, perhaps containing 4 or 6 component cameras, airming in the horizontal plane,  able to record everything in a horizontal plane, mounted on your head just like a 'propellor beanie', famous from the early 1960's.  A cable will go down to a smart phone in your pocket. https://www.youtube.com/watch?v=NxhzahiQshQ    Maybe something like this already exists? It certainly ought to.

The main question I have is whether a smartphone has the capability to digitize (or at least record?) the output from as many as six HD cameras at a single time

My personal experience is that you run into all 4 limits of USB bandwidth, video compression cycles, disk bandwidth, and network bandwidth, streaming that much at once on a single commonly available device.  You can of course compensate by dropping most of the frames, maybe ones from cameras showing little activity, but in my opinion that many cameras would be better done with more customized hardware than an off the shelf phone.  I'd prefer to focus on phones because anyone can buy/borrow/beg one, but make design choices that allow adding support for customized setups too.

Punk-Stasi said:

Keep preaching surveillance technofascism Jim, you're doing a great job.

I reply more below, but it seems the second half of this sentence is the truth.  A commonly-available tool is not fascim, and this is already a technocratic list.  Jim is discussing empowering common people to _fight_ surveillance technofascism via community "souveillance" which is where masses are empowered to observe and share evidence of authorities.

grarpamp said:

Use the phone's USB port to attach the RTL-SDR GnuRadio etc
transmitter dongle, or use the phone's Wi-Fi to speak IP

This sounds like a wonderful and important thing to support on both the recording and sending side.

marcos said:

All technology is a liability if there are no leaders. They amplify the good and the bad equally.  Unless there are leaders.  Until then they consume resources.

This sounds incredibly intelligent.  We have leaders right now, we don't want them, and the balance of technological privilege recently swung toward them.

Punk-Stasi said:

journos have been using 'technology' for a while...to serve and proptect the private-government mafia. 
The sort of propaganda you're trying to peddle here is infinitely ridiculous. You pick ONE event that suits your 'narrative' while IGNORING A MILLION

Punk, it sounds like you know of a lot of suffering at the hands of technology that may not have been included in this discussion.  In america, we still believe we have a huge majority of hackers who distrust the government: although it is true we are all misled by our media and culture.  Could you be more precise about what we need to know, or are you maybe looking for understanding that technology tends to cause undiscussed genocide?  The million events you describe may have never reached our news.