I’m Mike Satterthwaite and I’m product and installation manager for the Broadcast Systems Development Team.

We are one of the teams inside the BBC working on internal technology development. We normally develop products and solutions when there is nothing fit for purpose on the commercial market. This may involve integrating commercial products with internally developed ‘glue ware’.

Raven at Lund Point for HD Olympic broadcasts


As a department our philosophy is to develop everything as reusable components that can be dropped into multiple workflows to fulfil a host of different needs across the organisation.

We try to use open source where possible as we subscribe to the opening and fair-sharing of software and are always keen to save the BBC money. As a whole we gives back to the same community by funding contributions to those open source projects.

Our biggest ‘customers’ are BBC News and Newsgathering both in the UK and also the international news bureaus and our systems are installed across the globe.

One of the products we have been developing over the last few years is Raven.

The original specification for Raven was for a box that would replace a tape deck in news satellite vans allowing news crews to do file based ingest when they are out in the field.

The BBC and other broadcasters have been moving away from tape based delivery to file based working over the last few years and, in my opinion, it’s a much bigger challenge than the move to HD. This is because there are so many different elements which need to work in unity with existing and immovable systems and infrastructures.

As well as the software requirements there were also environmental factors such as the physical need to fit the box into the space left by the removed tape deck.

The box needed to be able to accept different card formats because although the BBC uses a Sony PMW500 camera that records on SxS cards in the XDCAM codec, other news producers will use different types of cameras, cards and codecs. Footage is often shared between camera crews in the field so the box needed to be able to read anything that was required.

Raven was developed as an application stack consisting of:


We put this on commodity hardware, things that anyone can go out and buy from the shops, so it’s effectively just a PC you could have at home with the addition of a baseband video interface card from Blackmagic Design.

The Raven interface


It runs on Ubuntu, a distribution of the Linux operating system and makes a lot of use of FFMBC for media manipulation.

BBC News were keen for the box to act like a tape deck so they could record video into it and also play video out of it onto a pre-existing infrastructure. As there were no longer any tapes Raven itself therefore needed to have some sort of storage element built in.

News also wanted the ability to take files off Raven and edit them quickly in the field then drop the piece back on the box and play it out directly.

It’s this kind of challenge which puts my team in their element because we were expected to develop a solution within a pre-existing problem space without changing anything else around it.

For example, as the satellite trucks were designed around baseband video i.e. real video voltages going down cables as opposed to IP, Raven had to bridge this gap.

After solving the initial problem the next step in the development of Raven was stimulated by the HD broadcast of the Royal Wedding in April 2011. At this point it became obvious we would have to consider more storage to scale with the growing requirements.

How could we join several Raven boxes together and share between them? We started to look at different ways of approaching this and think about a structure beyond a single box.

We solved this issue by developing something called a Raven nest, which is essentially a group of Ravens with a core storage server called a Ravenstore. This allowed all Ravens to access the same material for both recording and play out as well as sharing with editors.

The next challenge for the Raven was the Paris elections in 2012 where we experimented with media tagging.

This is when the clips or video being recorded are viewed and then given an appropriate associated label or ‘tag’. This tag then determines where the clips appear in a folder structure. So someone who’s sat in an edit suit or in front of a laptop in the field can look at a certain folder associated with that tag and edit only the relevant material.

Clips can have any number of tags but Raven doesn’t copy the recording multiple times. Instead by making use of the Linux operating system we are able to symlink the same file in multiple locations without taking up additional space.

Raven 3U


Undoubtedly the biggest challenge for Raven was the 2012 Olympics.

Nine months before the start of the Games we decided on a set of new features that Raven needed to deliver. However, the nature of news planning meant a lot of the final designs for the system were unknown until closer to the event. In some cases the workflows were changing literally the night before.

We installed eight Raven boxes in Lund Point, where the BBC News headlines were broadcast, as well as centralised storage for all the prerecorded packages which were played out during News bulletins.

There was hardware control of each Raven box and individuals doing editing off that shared storage in Final Cut Pro.

This ultimately became the system that played out video live for the One, Six and Ten o’clock news in HD throughout the whole two weeks of the Olympics and didn’t drop a single frame of the one million it broadcast.

When you consider that two and a half years before this Raven was just an idea, to then be finding it driving the HD News bulletins of the Olympics is a significant achievement.

However, when you look at the level of requirements for News over the Olympics I don’t think there was another option. People had become so familiar with using Raven by this point and they expected a lot from the product and weren’t let down.

Ravens are now doing everything from recording audio for logging purposes to live playout in Singapore to being used for archive purposes and they are still used in every satellite vehicle the BBC owns.

There are now around 350 to 400 Ravens used around different parts of the BBC, all built by my department either in the original 3units size or the smaller Raven minis which most people now have. We also have some built around Hewlett Packard hardware.

You can fit two of the minis side by side on a 19 inch rack bay and it also means you can have one with a smaller tape deck next to it. The original, larger version is meant to be mounted on a rack and be a permanent installation unit.

Going back to our departmental philosophy Raven has a full API means that it has the capacity to be reused in multiple different ways by other areas of the BBC.

For example, in Northern Ireland they have written a BNCS driver to control the Raven through the same interface they previously used to remotely control a tape deck. BNCS, now called Colledia Control, is the broadcast network control system used by the BBC to drive a lot of our broadcast devices.

Raven continually has to adapt to the next change in the business workflow. You have to be able to adapt as the broadcast industry is constantly changing at an ever increasing rate.

It would be interesting to hear what you think about Raven and your experiences of the file based transition.

Michael Satterthwaite is product and installation manager for the Broadcast Systems Development Team.

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  • Comment number 13. Posted by Chris Hills

    on 24 May 2013 17:36

    Thank you for your follow up Michael. I shall consider writing a FOIA request. For the record, I do not work in the industry so I am not interested in any commercial gain. I am curious as to how it works, and it could have potential applications for non-profits and charities.

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  • Comment number 12. Posted by Michael Satterthwaite

    on 23 May 2013 13:21

    Chris and Ewan, thanks for your follow ups. I respect your opinion and the BBC often open sources code/software to benefit the wider industry but before doing so we take a number of factors into consideration including the impact this would have on the market. In the case of Raven, after careful consideration we decided not to open source because of this. However, I've been told that the BBC will be happy to consider your request under FOI. The best way for you to do this would be to submit your request through our website - http://www.bbc.co.uk/foi/requesting_information/ including a name and email address for response. Further guidance about making a request is available on the ICO’s website: http://ico.org.uk/for_the_public/official_information

  • Comment number 11. Posted by _Ewan_

    on 20 May 2013 14:45

    "Raven is not currently available outside the BBC"

    But why not? You sound like someone who gets it, and it's not as if the BBC can be short of people that understand copyright licensing. What consideration went in to releasing the code, and what was the reasoning behind the decision not to?

    And if it helps, you can consider that a FOIA request.

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  • Comment number 10. Posted by Chris Hills

    on 18 May 2013 07:51

    As a TV license payer I believe that software developed by the BBC should be open source and made available to everyone under Freedom of Information.

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  • Comment number 9. Posted by Michael Satterthwaite

    on 16 May 2013 18:44

    Didi Kunz and _Ewan_, thank you for your questions. Raven is not currently available outside the BBC. What is available is FFmbc available from http://code.google.com/p/ffmbc/ which is used for media manipulation. The BBC has contributed to FFmbc directly via the development team’s Mark Himsley (see his work on v0.7 http://mdsh.com/wiki/jsp/Wiki?FFmbc+0.7) under GPL2 and also by paying external developers to add new functionality to the FFmbc codebase. Mark has also contributed to FFmpeg see http://git.videolan.org/?p=ffmpeg.git&a=search&h=HEAD&st=author&s=himsley and http://git.videolan.org/?p=ffmpeg.git&a=search&h=HEAD&st=commit&s=himsley under the LGPL.

    heretic29a, I appreciate your comments. There will be more posts on the blog from me in the coming weeks about other solutions my team develop so keep an eye out for further updates.

    Daniel , thank you for your question, the case in the top photo is an Element Q by Thermaltake.

  • Comment number 8. Posted by icogill

    on 16 May 2013 11:06

    Would be really interesting to hear more about the Ravenstore/ Raven nest - what sort of shared storage and networking is being used?

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  • Comment number 7. Posted by Daniel

    on 15 May 2013 06:20

    Michael Satterthwaite, who is the manufacture of the computer case on the top photo ?
    If you are note allowd to post on public bbc pages, please let me know and you can send it by mail...

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  • Comment number 6. Posted by heretic29a

    on 14 May 2013 16:47

    Sounds like an impressive piece of kit, You should do more articles like this, as a software dev mysely it's always fascinating to get a glimpse into the world of other types of developers.

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  • Comment number 5. Posted by _Ewan_

    on 14 May 2013 16:39

    "We try to use open source where possible as we subscribe to the opening and fair-sharing of software"

    From where can interested people download the software you've written for this project, and under what licence has it been published?

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  • Comment number 4. Posted by Didi Kunz

    on 14 May 2013 16:28

    Nice piece of software. Can I download it, outside BBC?

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