Posts Tagged ‘osprey’

Finally – an Osprey Alternative

Wednesday, October 1st, 2014

For years, video capture, at least for media monitoring companies, was dependent on Osprey capture cards.  They are the best there are in the field, and once you try it, you don’t look for anything else anywhere else.  You just pay the price and are satisfied with it.  The card has excellent drivers with tons of options, SimulStream as an (paying) option, …  real real beauty.

However, as we said above, it is pricey.  For Osprey 460e, you need to hand out about $1200 USD.  That’s $300 per channel.

Now, click here:

http://www.vd-shop.de/simultaneously-capture-d130fpsinput-interface-rcabnc-inter-p-591.html

YES!  6 channels for 320 Euro ($400 USD).  I won’t calculate per channel price here, since it is already obvious that Osprey is beaten, at least as price is concerned.

In fact, lets see, on a setup of say 24 channels, how much do you save using new cards:

Osprey: 6 cards, $7200
VCAE: 4 cards, $1600

So only on capture hardware, you could save $5600.  Add to that lower cost of hardware (servers) since you can pack everything in lesser amount of PCs.

So, to follow up on the excitement of finding that this card exists, I immediately ordered a sample to try it with our capture software.  It came in few days, and we went on and installed it…

And the story has to end here, since card works as it should out of the box, enabling media monitoring installations to be even cheaper now.  Not only that, a card has an interesting form factor and low consumption, and will prove ideal in multiple channel scenarios.

I will update the article with 24/7 testing in real world, as soon as we make an installation that has such properties.

Capturing and archiving of DVB-T signal

Monday, November 28th, 2011

No matter if it’s for compliance recording so you will capture and save your own broadcast, or you are doing media monitoring and you would like to capture multiple signals of the air, you have some interesting choices here.

Let’s explore in detail your options on the subject, whether it’s one channel or multiple channel recording.

One channel DVB-T recorder

Recording of one channel is simple no matter how you choose to record it.  Let me present two main options here for you, so you could see what is most applicable in your situation.

Simplest way of recording would be to have one set top box for DVB-T, and use it to send composite signal into the computer via the Osprey 210 card.  It is the most robust solution, but it has some (serious) drawbacks:

  • cheap DVB-T tuners can ‘lock’ and freeze the picture
  • low quality tuners can also de-sync audio and video with time – and you need 24/7 operation here
  • you’ll need extra power connector for the set top box
  • STB-s are producing extra heat

Alternative way of recording is to use DVB-T card such as Asus MyCinema-ES3-110, use software such as TubeSink to tune on a frequency and extract the channel required from it (this is called DEMUX-ing) and forward the extracted channel to the VideoPhill Recorder for further processing (recording, streaming, …).

BTW, TubeSink mentioned above can be used even without VideoPhill Recorder, as it DEMUXes the channels and can forward them to any computer on your network as an UDP Transport Stream that can be playable with VLC.  It you want to use it for non-commercial purposes, download it from here.

So in the case on 1 channel DVB-T recording, I would say that it remains uncertain whether to use external set top box with Osprey capture card, or go with pure software solution and some simple of-the-shelf DVB-T tuner.

But in case of…

Multiple channels DVB-T recording facility

Same options are available at multiple channel recording facilities – but here is the catch.  As you might probably know, multiple DVB-T channels are packed and are transmitted at one frequency and that is called multiplexing.  The carrier for the channels that are transmitted is called MULTIPLEX (MUX for short).  In several occasions it has 4 channels, and sometimes it can have as much as 16 or more channels.

Current recommended recorder density (channels per machine) is 4. One machine packed with Osprey 460e will do 4 channels just fine.

So, let’s say that we need 16 channels and they are scattered across 3 MUX-es (we have such situation here in Zagreb).  Using a conventional method (I would say that having 16 STBs is conventional, as bizarre as it seems) you’ll need the:

  • 4 recording servers
  • 4 Osprey 460e cards
  • 16 DVB-T set top boxes
  • PLENTY of mains outlets
  • some kind of distribution to have the signal distributed to all 16STBs

Since you see where I’m coming to, let me suggest the following; let’s use TubeSink to control 3 tuners in TWO MACHINEs, and save on 4 Ospreys and 2 PCs, and the rest of the unnecessary equipment.

We’ll put 2 tuners into one machine, and one tuner in the second machine.  If the channel per MUX distribution is such that each machine has it’s 8 channels, fine.  If not, we’ll instruct TubeSink to forward the Transport Stream to ANOTHER machine and that machine will perform recording.  In that way, load will be completely balanced between two machines, and you’ll have your 16 channels recorder in a nice and compact fashion.

Even more compact?

Yes, it can go even further.  There are dual DVB-T tuners such as WinTV-HVR-2200 that can provide tuning to two frequencies at once, and with it, you could record as much channels there are in two MUXes at one machine.  Today, even desktop processors such as i7 can encode 8 channels of video in real time.  So, with proper CPU (or multiple CPUs on server computers) – even 16 channels could be encoded in one compact 2U rack mounted unit.

However… (serious problem)

Using PC based DVB-T cards will only work with free to air channels.  If any of your channels are encrypted, solution described above will NOT work.

SD-SDI compliance recording

Monday, November 28th, 2011

I will try to write something about creating the archive for the compliance recording purposes from the SD-SDI source.  This post is in a response from an repeated inquiries about system that would create such an archive.

Compliance recording in general

Just to remind us – compliance recording serves only one purpose – to prove or disprove that something went on the air at some time.  That is the first and the last thing that this technology is used for.  There is no any requirement on the content of the signal – it just have to be good enough for someone to see basic stuff that’s in there .

This one business requirement is countered from the other side with need to create the archiving system to be as affordable as possible.  And the cost of the system, if we count out the software involved (system and application part) is highly dependent on the:

  • picture quality
  • number of channels recorded
  • number of possible outputs needed
  • and days of the archive that should be kept

Picture (ie. video) quality is directly proportional to the BITRATE of the video that is recorded.  More bitrate, more apparent quality, both in picture resolution, object motion, and so on.  For example, most recorded videos that you might have on your computer are in between 700 and 1000 kbit and are recorded with DivX or similar encoder.  Watching a movie at 1000 kbit bitrate is highly enjoyable, and everything above that is required ONLY for HD or HD-Ready content.

Compliance recording means recording what’s on the air

Many people forget that when you do compliance recording, you have to record what was coming out of your transmitter array, not the final that you are broadcasting.  In case your link went down, or your output HF amplifier burned, your endpoint picture will be NOTHING, and if you are recording your output, there will be a great discrepancy in your logs.

So suggestion: drop the thinking about recording SD-SDI, and try to record what comes back from the air, in the form of the analog or DVB-T signal.  That is the REAL broadcast that your viewers see.

The conflict of interest

We all want stuff to be as cheap as possible.  In order to build a recording system that is affordable, we have to balance between various things, but here I’ll try to explore the differences when SD-SDI signal capture is required.

I will postulate this input parameters for the archive that will serve as example here:

  • video bitrate: 512 kbit
  • audio bitrate: 64 kbit
  • archive duration (number of days to keep from today): 92 (3 months)
  • number of channels that needs recording: 4
  • required outputs: both WMV (Windows Media Video) and h.264 (at the same time)
  • recording resolution: 3/4 of PAL D1 picture size so: 540×432

In order to calculate hard drive space requirements for this here, I’ll use the online bitrate calculator here on this blog.

Table below taken from the calculator itself.

Video Bitrate Audio Bitrate Total Bitrate Days Channels Disk Space
512 kbit/s 64 kbit/s 2304 kbit/s 92 4 2183.20 GB

So we need 2200GB of net drive space.  In order to provide that kind of space with some fault tolerance, I would recommend having two drives such as WD CAVIAR GREEN 2500GB connected in a MIRROR VOLUME (RAID1).  There is no need for additional system drive, and almost all new motherboards can provide on-board implementation of RAID1 – mirroring.

I’m kind of beating around the bush here – because main point of this article should be to provide you with a choice of whether to use original SD-SDI signal or convert to composite signal (or use the signal that comes back).

Osprey vs DeckLink

The choice that lies before us is either to use Osprey 460e card, or a DeckLink Quad card.  List price for the Osprey is about $1200, and two DeckLink Quad card is about $1000.  So, the first impression is that you’ll go cheaper with DeckLink.  But…

So far, the Osprey has proven itself to be absolute master of video capture.  Every system deployed so far didn’t have any problems with the card whatsoever.  You plug it in, install drivers, and it works.  And with Osprey 460e, you’ll use only ONE PCI-e slot.  Other slot, if there is any, will be used by the graphics card.

Same thing about the slots applies to DeckLink as well.  However, there is “now shipping” image below the DeckLink Quad card name, and it implies something – it is red-hot new.  Despite the fact that VideoPhill Recorder will work with it, I don’t know how reliable it will be in 4 channel simultaneous recording situations.

My point – it has to prove itself – and if it does, it will be a great addition to VideoPhill arsenal.