Electrical Network Frequency analysis

I've been running a training course at the Metropolitan Police's Video and Audio Forensic facility in Sydenham. I've been able to chat to some of the technical forensic guys and one thing has blown me away - Electrical Network Frequency analysis. 

The whole of the UK mainland is on an electrical power-grid; as generators run up and connect to the grid they have to be at the same frequency and phase-locked to the 50hz AC supply of the rest of the country (or there would be sparks!). Now although the mains supply is pretty accurate at 50hz load variations cause momentary changes that are reflected across the whole country; typically less than 0.2hz either way - mains can be (at any moment) 49.8 through to 50.2hz, but even over short integration periods it is darn close to fifty. I couldn't find any info for the UK, but here are some traces taken from the mains supply in Romania in 1998, three towns, separated by 800Km. 

Notice how the waveforms track each other precisely. It turns out that the pseudo-random sequence is very identifiable after the event. For this reason the MET have been sampling it for the last five years. They know exactly what the mains in mainland UK was doing at any point since 2007. It also turns out that induced mains hum is present in most audio recordings; either through pick-up in the power supply or from the hum of lightbulbs etc. You have to work hard to make an audio recording that doesn't have this watermark down there in the noise. 

They've even discovered they can extract it from the regular flicker of lights on video-recordings. This means that you have a forensic tool for checking the record date and time on evidence. 

There is a Wikipedia page on the subject and they've challenged me to send them some samples of speech recordings I've made over the years to see if they can time-match them.

Netvue - business class IP TV system

I went to a very impressive demo at Sony BMG today - they have an Exterity-based office IP-TV system as provided/configured/integrated by NetVue. They seemed to have really got it right. The system is based on IGMP multicast over IP which relies on IGMP-compliant switches (think Cisco 3750 or equivelent HP ProCurve). Essentially it means that only the streams that are being watched are present on the network and then only the data is present on those segments with active clients.
Set-top boxes are tiny and around the £250 mark. The PC client comes in at £35 per seat.
What I found to be the really clever side of it was the TV gateway which takes DVB-T multiplexes and strips out all the transport streams and makes them available. So, with their 1u chasis you can expose all six FreeView Muxes (55 stations?) on the network for around £8k - to build an RF-system with similar abilities would cost many times this and the pictures would look awful (I know - I've built a few!). If you need to hang a video device (Sky STB, DVD player, etc.) their STB & PC client can both back-propagate IR control.
As mentioned - I kept getting the feeling that 'they've done this right' - it's a very complete/robust solution. I like the idea that when they can avoid it they don't re-encode the video and assume the clients can replay MPEG-2 transport streams (or in the case of the HD STB H.264 transport streams).

I can't wait to spec one of these!

TriCaster

I had a really informative demo at CVP. I'm normally quite dismissive of all-in-one solutions that promise the Earth for a low-low sub-ten-grand price. I've seen NewTek's boxes demo'ed at trade shows for a decade but never seen them in a television facility or an OB truck. I always assumed that it was a very clever demo that avoided all the hard stuff (have you ever done that at a trade show?!). The expression Graham uses is 'suspiciously cheap'! Anyhow - I had a Bruce Springsteen moment when I got to spend an afternoon playing around with the TriCaster.

Now not suggesting you build an LE studio around it but it does include everything a small studio would need - six component video inputs, two virtual VTRs (with a rundown scheduler), eight input switcher (re-syncs all i/p's), DVE, keyers, mattes, caption generator/graphics subsystem and a virtual studio model.
When you design your set you tell it how things are scaled and if you then cut a real camera between three virtual positions it re-sizes the talent accordingly so - with only three cameras you can cut between maybe nine virtual shots and it really works - it seems like you have three cameras looking at each shot. It records an AVI to it's internal drive as the safety record and the virtual set knows all about plasmas etc (so you can play in as if it really was an in-shot monitor) - an in-set monitor is one of the things you can have in the model of a studio and you assign it as a destination and cut live feeds (cameras, VTs) or virtual sources (GFX, Virtual VT sources) to it and if there are any 'shiny' surfaces in the set - table tops, glasses of water etc. they pick up reflections of cameras sources, plasmas etc.
iVGA is another unique feature where the system can take a real-time VGA feed over the network. It will scale or follow the mouse for presentations and the quality was superb. I can't think of another gadget that allows you to do that without using a scaler.
I was blown away - I kept looking for the SGI workstation behind the demo booth!

I'm hoping to base a little three-camera web-casting studio around one in the next couple of months.

Isilon

Good news everyone! I have seen the future and it runs OneFS. Yesterday I had one of those Bruce Springsteen moments as Rupert and Rob Anderson (from Isilon) took me through the configuration and operation of their distributed storage system.

The Isilon IQ clustered storage product line addresses enterprises' full spectrum of storage needs - from the highest performance Tier-1 applications to Tier-2 enterprise archive, disk-to-disk backup and disaster recovery. Powered by OneFS, the Isilon IQ family of products creates a single pool of expandable storage that is easy to install and grow - once racked, a 10, 50 or 100+ terabyte cluster takes less than 10 minutes to configure and set up, and capacity can be added on the fly in less than 60 seconds with no downtime.

Their OneFS file-system is distributed across as many nodes as you have and regardless of model (the baby 200 model that has only gig ethernet) or the larger infiniband attached nodes you really can expand and contract the storage pool on the fly and without having to re-format to mount new partitions etc. I imagine this is the kind of technology that makes data centres run smoothly. Yesterday I was able to build a 3 x 2 Terrabyte cluster in a matter of minutes, upgrade the software running on the nodes by upgrading one node only (the OS which is FreeBSD runs on the distributed filing system as well) and then attach a fourth node that was running a previous version of the OS and have it upgrade itself. All this happened while the storage was active and being used and the client workstations didn't see any loss of space or loss of performance! When you compare it to other NAS or SAN solutions it is truly miraculous.
In terms of performance it currently connects to the workstations over gigabit ethernet but they are promising faster connectivity. Traditional performance bottlenecks are addressed by including an IQ Accelerator in you configuration - this essentially gives you a bigger in-road to the storage;

Isilon IQ Accelerators automatically join an Isilon IQ storage cluster in less than 15 seconds and add processing power, memory, bandwidth, and parallel read and write access to a single file system and fully symmetric storage cluster. This is in stark contrast to the limitations of traditional storage and namespace aggregation technologies that require customers to add expensive file server heads and disparate devices to increase performance. These legacy approaches are difficult to manage and fail to aggregate total throughput across a unified storage system.

So, you have a storage pool accessible by a single attachment point which can grow infinitely without the usual performance hit as the filesystem has to address multiple virtualised pools.
I am so impressed - watch this space!

http://www.root6.com/Home/Products/productinfo/network_storage/isilon.htm

"I have seen the future of rock and roll, and it's name is Bruce Springsteen" - Jon Landau, Rolling Stone Magazine, 1974

But in this instance it was a new style of high definition TFT-based display. Bightside have a range of displays that aren't rear-illuminated with fluorescent tubes but with an array of hi-bright LEDs that are modulated with the luminance of the image being displayed. The array of LEDs is much lower-res than the 1920x1080 pixel matrix and so the real image (as displayed on the LCD) is modified with a masking signal to get the illumination to the correct resolution and the results are superb. A dynamic range of near 100dBs (that's fourteen stops to the cinematographers) and a maximum light output of 3000 cd/m² (you line-up a monitor for TV grading with peak white at 80 cd/m²!). I couldn't vouch for the colourimetry but it did look pretty close to illumninant-D. The detail in the blacks was astonishing and next to a Sony GDM monitor (which a lot of people use for grading!) the pictures looked remarkable. It was like a light-box with a moving transparency on it! I hope our friends at Filmlight implement a Truelight LUT for this device and I think that you'll see these in film grading suites really soon.

Interestingly there were a couple of facilities engineers and MDs there and they didn't seem to get it - the one quote I'll remember for a while was "we could use one in reception..."! I suppose when folks first looked at colour TV, stereo audio, digital video etc etc there were folks who couldn't see how to make it fit into their workflow and therefore couldn't see any value in it. I was blown away, however.

They also had a very cool compression system for reducing the data-load on 32-bit high dynamic range images.