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Dirac: BBC Open Source Video Codec 523

NickFitz writes "Need To Know this week has a piece about Dirac, a BBC R&D project to produce a video codec, which has been released as an Open Source project. From BBCi: 'Dirac is a general-purpose video codec aimed at resolutions from QCIF (180x144) to HDTV (1920x1080) progressive or interlaced... Our algorithm seems to give a two-fold reduction in bit rate over MPEG-2 for high definition video (e.g. 1920x1080 pixels), its original target application. It has been further developed to optimise it for internet streaming resolutions.'"
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Dirac: BBC Open Source Video Codec

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  • Ahh codecs. (Score:2, Funny)

    by Anonymous Coward
    The great thing about them is that there are so many to choose from and support.
  • Finally!!! (Score:5, Funny)

    by WwWonka ( 545303 ) on Friday April 30, 2004 @01:52PM (#9020678)
    BBC Open Source Video Codec

    Finally a codec to convert all the dry witty intelligent British TV humor over to bland cliche' stale American TV humor!
  • Duplicating work? (Score:3, Insightful)

    by bobbis.u ( 703273 ) on Friday April 30, 2004 @01:52PM (#9020680)
    Seems like a bit of a waste of license payers money when there already a several open source video codecs (eg. Ogg Theora, 3ivx). What does this offer that those don't?
    • Re:Duplicating work? (Score:2, Informative)

      by bobbis.u ( 703273 )
      I of course meant xvid, not 3ivx (3ivx isn't open source).
    • Re:Duplicating work? (Score:5, Informative)

      by Uzik2 ( 679490 ) on Friday April 30, 2004 @01:56PM (#9020732)
      Theora doesn't have a working windows codec.
      Windows is most of the marketplace.
    • It seems as if their codec performs very well (losslessly?) at very high resolutions, i.e. the ones the Beeb would need for HDTV. This would provide better (visual) quality programs over existing lines e.g. cable, satellite. I have a feeling the codec will not have a practical use for everyday computer users, but will be used more for video production.
    • by Anonymous Coward
      Codecs have varying quality/compression tradeoffs for different source material, intellectual property hassles (not all which are known up front), varying API support, etc. So the more that are available the better.
    • "What does this offer that those don't?"

      Its British.

    • Re:Duplicating work? (Score:4, Interesting)

      by SpinyNorman ( 33776 ) on Friday April 30, 2004 @02:06PM (#9020838)
      It's wavelet based, so presumably it doesn't suffer from the block artifacts of MPEG-2 & MPRG-4.
    • by Anonymous Coward on Friday April 30, 2004 @02:16PM (#9020948)
      US codecs incorrectly drop a vowel from colour, so a British codec is bound to look better.

    • by evilviper ( 135110 ) on Friday April 30, 2004 @02:18PM (#9020971) Journal
      there already a several open source video codecs (eg. Ogg Theora, 3ivx)

      With Xvid, ffmpeg/libavcodec, and any others based on MPEG-4, the code may be open source, but you can't use it legally, without paying for an MPEG-4 license. MPEG-4 is a lot like MP3 in that sense.

      Theora would be nice, but it's perpetually Alpha... I was excited about it at first too, but now it seems it's going to take another year before the code is even in beta, and probably two years before it reaches 1.0, when there will be ports to non-Linux platforms. By then, it will be about as advanced as MPEG-1 is today... Way behind the times.

      However, VP3 (the codec Theora is based upon) is a rather good codec (despite the brain-dead review it got at doom9). It is free, open source, etc. There are encoders and decoders for Windows/Mac, and numerous decoders for Unix systems. It would really work great, and I have no idea why it hasn't been more popular to date.

      If there was some program that could encode VP3 video on Unix systems, I would be using VP3/Vorbis excluively for encoding everything. However, avifile, MPlayer, ffmpeg, none can encode to VP3, so it seems Unix systems are out of luck.

      That said, I'd bet the BBC will be doing their encoding on Windows or Mac OS machines anyhow, so I don't know why they don't use VP3.
    • by Ride-My-Rocket ( 96935 ) on Friday April 30, 2004 @02:19PM (#9020989) Homepage
      Seems like a bit of a waste of license payers money when there already a several open source video codecs (eg. Ogg Theora, 3ivx). What does this offer that those don't?

      Does the current work being done on Linux seem like a waste of time and money, when there are already several other operating systems (Windows, Macintosh, Unix) available? And don't try and use the argument "but those are closed source; open source is better!" argument -- in the end, it's just software people use, regardless of the licensing / development model.

      Getting back on-topic: apparently it offers the BBC something that warrants the time, effort and money required to fund such an undertaking. At the very least, it's yet another example of big companies using open-source to reduce costs and/or fulfill their own specific needs, and can only encourage other companies to fund future OSS development efforts.
  • by the_2nd_coming ( 444906 ) on Friday April 30, 2004 @01:54PM (#9020694) Homepage
    right now I have good quality with 3vix but it is 1 gig.

    if this can get me to 700 MBs at the same quality (about 85 in the 3vix) that would rock!!!
  • by koniosis ( 657156 ) <> on Friday April 30, 2004 @01:54PM (#9020706)
    Hopefully the BBC will use this instead of RAM, silly real player!
  • BBC Archive (Score:3, Interesting)

    by Anonymous Coward on Friday April 30, 2004 @01:55PM (#9020713)
    Could this be related to the archive of video content they are purported to be setting up? Seems like a very unnessecary step to accomplish that, unless they have some sort of conflict with the legalaties of other codecs out there...
    • If anyone is interested in the BBC Archive that was announced last year, the /. article about it is here []. If this did happen with the archive being stored in this format at a high-resolution, it really would be an incredible resource.
  • Well, I'll have to test it out first, but its a pain encoding in Divix, so I will have to see if this is a little less CPU intensive (or really IDE bus intensive). Capturing and converting live streaming video at 800x600 is intensive...

    Anyway it can't hurt especially if it saves me some space (you would be surprised how fast you can fill up 1/2 a terrabyte with video capturing).

  • by Lord_Dweomer ( 648696 ) on Friday April 30, 2004 @01:57PM (#9020739) Homepage
    I really hope this leads to more free educational videos online. The BBC has been doing a great job of making that material available for free, and any thing that helps improve the quality of that content is a good thing.

    Their documentaries are so interesting that I often choose to watch them over other movies or shows I may have on my computer. Bravo BBC.

  • A bit wary (Score:5, Insightful)

    by bsd4me ( 759597 ) on Friday April 30, 2004 @01:59PM (#9020771)

    I would be a bit wary of a codec that claims to be all things to all people, ie supporting broadcast-quality HDTV and internet-quality video

    Video codecs typically have ``sweet-spots'' for resolution and bitrate. The MPEG specs work well for higher bitrate video, and we have several codecs that work well for lower bitrate video.

    Also, MPEG video quality can vary from encoder to encoder. The specs only define the bitstream, and the encoder can do what it wants. This is why there is a huge difference between the quality that Media Cleaner produces versus a multi-chip hardware encoder found in a cable plant.

    • Re:A bit wary (Score:4, Informative)

      by ca1v1n ( 135902 ) <snook AT guanotronic DOT com> on Friday April 30, 2004 @03:02PM (#9021483)
      That's because many codecs have performance tuning parameters built into the encoding standard, like with MPEG. Wavelet-based methods don't need to do this, so their performance tends to scale quite smoothly. More traditional compression techniques may still beat them out at their "sweet spots", but the wavelet methods are very general.
    • Re:A bit wary (Score:5, Informative)

      by hak1du ( 761835 ) on Friday April 30, 2004 @03:07PM (#9021522) Journal
      Video codecs typically have ``sweet-spots'' for resolution and bitrate.

      Well, if your video compressor has notions of "8x8 blocks" and "16x16 blocks" hardwired into it, that is not exactly surprising. That's the kind of technology that current codecs use.

      If they use wavelets and motion compensation correctly, there is no reason why it shouldn't scale well across a large range of resolutions.
  • by Anonymous Coward on Friday April 30, 2004 @02:00PM (#9020775)
    Looks good, but why are all the male American comedy leads now in drag???
  • MPEG4? (Score:5, Insightful)

    by cybermace5 ( 446439 ) <> on Friday April 30, 2004 @02:00PM (#9020780) Homepage Journal
    Why would they compare it to MPEG2? In order to impress me, you'll have to compare quality and bitrates with MPEG4.

    • Re:MPEG4? (Score:3, Insightful)

      by Jameth ( 664111 )
      MPEG4 is not that special at very high bitrates. MPEG4 is for low bitrates almost exclusively. This makes for small files which look good enough, but not files which look perfect.
      • Re:MPEG4? (Score:4, Informative)

        by neurojab ( 15737 ) on Friday April 30, 2004 @02:22PM (#9021018)
        >MPEG4 is not that special at very high bitrates. MPEG4 is for low bitrates almost exclusively. This makes for small files which look good enough, but not files which look perfect.

        I've heard that before too, but if you compare an equal-bitrate Mpeg2 with Mpeg4, I think you'll find that Mpeg4 wins. The optimizations were designed for low bitrates, but help at high bitrates as well.

        • One of the biggest differences between MPEG4 and MPEG2 codecs is the seek times - that's the time between keyframes or I-frames (same thing, different terms).

          The typcial keyframe rate in MPEG4 stuff is around 8-10 seconds. In MPEG2 it tends to be around 2-5 ms, which is about as good as the eye gets, apparently. So, if you watch it from start to finish, that's fine - but if you want to do anything non-linear, MPEG2 gives a good win.

          In terms of broadcasting, you need to add the seek time onto the total '
          • MPEG2 keyframes (Score:4, Informative)

            by achurch ( 201270 ) on Saturday May 01, 2004 @08:16AM (#9026911) Homepage

            The typcial keyframe rate in MPEG4 stuff is around 8-10 seconds. In MPEG2 it tends to be around 2-5 ms

            Seeing as how one frame is 1/25 (0.04) or 1.001/30 (0.03) seconds depending on which part of the world you live in, 0.005 is just plain impossible. At least as far as DVDs go, MPEG2 keyframe intervals are usually 12-18 frames, which works out to 0.4-0.6 seconds for NTSC--still a lot less than MPEG4.

      • There's two kinds... (Score:4, Interesting)

        by Kjella ( 173770 ) on Friday April 30, 2004 @02:42PM (#9021252) Homepage
        Let's say you compare

        a) 640x360 vid at 1x bandwidth
        b) 640x360 vid at 9x bandwidth
        c) 1920x1080 vid at 9x bandwidth

        a) and c), MPEG4 will win. b) will be much much closer. What you define as "low" bitrates really depends on resolution. The dual-layer DVDs coming now should be able to do full HDTV resolution with somewhat better quality than a 1CD DVDrip. Since 2CD rips typically use 3-400mb on AC3 track, actually not that far away from 2CD rip. But something like 8-10Mbit (aren't they usually 1Mbit today?) is hardly a low-bitrate stream in my opinion...

    • Re:MPEG4? (Score:5, Informative)

      by happyfrogcow ( 708359 ) on Friday April 30, 2004 @02:11PM (#9020895)
      Isn't MPEG2 the standard for TV broadcasts?
      • Re:MPEG4? (Score:3, Informative)

        by jo_ham ( 604554 )
        Yes, for digital TV/Cable/Satellite.

        It is also used for DVD videos, but at a higher bitrate than is possible/normal for TV.
  • Fantastic News (Score:2, Insightful)

    by stephenry ( 648792 )
    This is absolutely brillant news!

    Ever since I heard that the BBC plans to put their achive on the internet it was clear that they would be far better served developing their own video codec. As a British Citizen, I am glad that those who have paid television licenses do not have to pay an additional toll in the form of Real Player.
  • Patent free (Score:5, Interesting)

    by Telex4 ( 265980 ) on Friday April 30, 2004 @02:09PM (#9020869) Homepage
    Even more impressive than the codec itself, in my opinion, is that they managed to develop a new video codec without infringing any patents! And given that it's the BBC, I assume they could go to court to defend themselves in prior art.

    Very cool. But then all the engineers in their R&D dept. are apparently very anti software patents, and have been doing their bit writing letters to that effect :-)
    • Re:Patent free (Score:4, Informative)

      by doc modulo ( 568776 ) on Friday April 30, 2004 @03:30PM (#9021748)
      Neither the article nor the /. summary said anything about patents.

      The BBC doesn't NEED to worry about patents because software patents don't exist in Europe. Although we're in danger of getting them because of the US and US companies influencing the European commission

      That weird shit only happens in the USA at the moment. Something as good as the BBC is doing would almost certainly be impossible in the US because of patents. When the BBC puts it's public knowledge on the net (wonderful documentaries), it will be illegal to watch/hear that info in the US as soon as a company comes out with a patent infringement claim.

      The only reason the rest of the world worries about software patents is because we want the people in the US to be able to use the software we're making. This might not last, as in the case of the BBC codec.

      I suggest US men-of-action types fix this situation, start with voting good guys/girls into office.
      • Re:Patent free (Score:3, Informative)

        by Telex4 ( 265980 )
        Neither the article nor the /. summary said anything about patents.

        Actually, the article says "Off the top of our heads, its mention of arithmetic coding is worrying, given how patent-encumbered that area is.".

        And having talked to some of the Dirac developers, they did develop it with patents in mind, not only to avoid licensing issues in the US, but also in case we do become lumbered with software patents in Europe.

        In fact, according to testimony at a recent conference in Brussels I attended, an awful
  • Wavelet Theory (Score:5, Informative)

    by Cocodude ( 693069 ) on Friday April 30, 2004 @02:10PM (#9020882) Homepage

    I went to a day at the Research and Development facility with the BBC, and saw a demonstration of Dirac.

    It does look quite impressive, and for those who are interested, I believe it works on wavelet theory. Lots of information on this is provided at but I believe its scalable frequency analysis enables significantly better compression than other codecs (typically DCT based?) out there.

    I think.

  • The team working on Ogg Theora has done pretty good work, and I wouldn't want them to drop their project, but collaboration would be great. As the two codecs seem to have largely different aims (Ogg Theora is low bitrate, anything compared to MPEG2 is high bitrate) they aren't even directly competing. I'm certain they both run into the same issues all the time, however, and some code sharing would help everyone out immensely.
  • BBC Archive (Score:5, Interesting)

    by enditallnow ( 177040 ) on Friday April 30, 2004 @02:14PM (#9020926)

    Did you ever consider that they intend to use this for their plans to put their archives online? []

    The poster stated that "It has been further developed to optimise it for internet streaming resolutions" which is one way for such a thing to be distributed. Have a look here. [] The register states that "The BBC's new media director, Ashley Highfield, said that a P2P network will allow the BBC to handle the volume of traffic it expects when the Internet Media Player (IMP) goes live. The IMP will enable users to download or stream content to their PC, laptop or palmtop computer."

    If this is the case then Aunty Beeb is well underway to providing the tools we will need for accessing their archives.

    -- Enditallnow

  • My question is... (Score:5, Insightful)

    by LilMikey ( 615759 ) on Friday April 30, 2004 @02:16PM (#9020952) Homepage
    How are they going to convince set-top manufacturers to support their codec or conglomerates to broadcast it? It's already been proven a hundred times over the superior and/or open rarely win out to their more profitable brethren. All the article states is there's a 'hint of a chance' of it being adopted by big media...
    • Re:My question is... (Score:3, Informative)

      by Mr Smidge ( 668120 )
      It's a video codec that's:
      * Better at compression that rival codecs.
      * Patent unencumbered (well, software patents in Europe is a separate discussion really).
      * Free.
      * Wavelet-based.
      * Suitable for internet broadcast and HDTV.

      If it's stable, believe me we techies will adopt it very quickly!
  • Great news (Score:3, Interesting)

    by ajs318 ( 655362 ) <sd_resp2@earthsh[ ] ['od.' in gap]> on Friday April 30, 2004 @02:20PM (#9021003)
    This is really wonderful news. The BBC is sharing its work with the Open Source community - and most of the British Open Source community are BBC TV licence payers.

    I am glad that the BBC has recognised the need for this codec to be Open Source. It means that everyone, not just those beholden to private corporations, will get the chance to experience BBC content. The BBC is also a highly influential body; I would be surprised if other European content providers did not display an interest in this. PAL was a joint development between the BBC and its German counterpart; SUSE is German.

    This is going to be one to watch.
  • by osewa77 ( 603622 ) <> on Friday April 30, 2004 @02:25PM (#9021049) Homepage
    What do companies do when they have products which, though not being best of breed, require huge and increasingly unjustifiable Research and Development funds? They go Open Source! (no, I am not naming names... sap db netscape interbase ...
  • by tetranz ( 446973 ) on Friday April 30, 2004 @02:33PM (#9021141)
    I mean all the BBC's services in general. I think I know the answer in assuming that the British people pay for it in tax and TV license fees. That's something I'm grateful for as a New Zealander living in the US. The BBC is a refreshing change to the somewhat mind numbing American news sources.

    My real question to Brits here is: How well is this burden accepted by the British people? Are the BBC TV and radio stations in the UK really non-commercial? I know the US government gives money to PBS and NPR but I don't know how it compares (especially per capita) to what the British government must spend on the BBC. It must cost a fortune and they are effectively supplying (IMHO) a good quality product for free to the rest of the world via internet and shortwave. I imagine some of the international motivation of the BBC stems back to the days of the old empire. It almost seems too good to be true.

    I assume that NPR and others like it around the world pay to carry the program. Maybe that earns a lot.

    This question came up in my mind the other day when the wi-fi radio was mentoned here on /. I definitely want on of those beside my bed when it becomes available. It seems like its the ideal thing for BBC listeners. I wonder if its availbility will significantly increase the load on their servers, all costing real money of course.

    • by hbr ( 556774 ) on Friday April 30, 2004 @03:12PM (#9021580)
      We pay about 120 UK pounds ($210 dollars at the current rather extreme exchange rate) per household for the priviledge. This is 10 pounds per month, but it is compulsory for all owners of television equipment (even if they could somehow fix their tuners to disable all BBC channels - on that note, does anyone know how I can fix my tuner to disable ITV2?). A comparison with this cost is the cost of satellite or cable "premium" channels which cost about 30 pounds per month (which makes it seem quite cheap really).

      I presume that the BBC sells its stuff abroad - it also has a number of commercial outlets (videos, etc). Despite not being able to advertise, it relentlessly promotes its own material (which can get quite tiresome and repetitive sometimes).

      Well, speaking as one British person, I'm quite happy to pay the license fee given the alternative. Radio 4 alone has got to be worth it. Of course, there are plenty of people who disagree with me here.

      What I can't understand is that they have the manpower to fund this project, but not to keep the ogg vorbis streams online... ( [])

  • Gotta love Auntie (Score:4, Interesting)

    by psyconaut ( 228947 ) on Friday April 30, 2004 @02:40PM (#9021226)
    I know that the BBC is somewhat of an enigma in broadcasting compared to what we're used to in North America (although some would argue networks like PBS and the Canadian Broadcasting Corporation are somewhat similar)....but I can't help think how utterly cool it is the BBC does this sort of thing. Progressive (no pun intended) stuff like putting their achives online is also really damn cool...not to mention the fact they have *gobs* of content that a traditional broadcaster wouldn't have (I've been taking Welsh language lessons courtesy of the BBC!).

  • by geeklawyer ( 85727 ) on Friday April 30, 2004 @03:01PM (#9021472) Homepage Journal
    I spoke to one of the BBC team demonstrating the codec at the London Linuxexpo. They said that the BBC had patented their codec although I was told that they have no real interest in patents. It was said to be a defensive patent whch they implied to me that they would not enforce, however the person I spoke to didnt know the details of the patent or its licencing scheme so it's a little unclear to me how this is going to work.

    They also said that while they had no objection to paying licensing fee's per se, and that they did pay MS and Real, these were so inflexible in their licencing that scaling up operations was problematic. Their expressed hope was that with such a codec widely adopted they could massively scale up operations such as streaming without being crippled with licencing costs, or having the administrative burden of unwieldy licensing schemes.

    • by JoeBuck ( 7947 ) on Friday April 30, 2004 @04:33PM (#9022433) Homepage

      If they patented the codec but then release an implementation under the GPL, it follows that they are effectively granting anyone permission to, as patent lawyers say, "practice the patent" as long as they do so in a GPL program that is a derivative work of what they released. It would be good of them to say so explicitly, though.

      There are a growing number of GPL-licensed patents now (patents where the owner permits GPL implementations). IBM has done this with a number of their patents.

  • Background (Score:5, Interesting)

    by ChaoticCoyote ( 195677 ) on Friday April 30, 2004 @03:13PM (#9021589) Homepage

    A matter of disclaimer: I've done some work on Dirac, for BBC, over the last several months. Here's a bit of background on Dirac:

    By nature, Dirac has many similarities to existing algorithms such and MPEG-2 and H.264/AVC -- however, Dirac is an original invention that uses wavelet transforms, arithmetic encoding, rate-distortion optimization, variable block-size motion compensation, and hierarchical motion estimation in some new and unique ways. Again, this is a research project, so there's much experimentation to be done!

    As a research project, Dirac continues to be analyzed, optimized, and documented. What you're seeing now is very preliminary code; I suspect it will improve and evolve dramatically in the coming months, both in terms of clarity and functionality. The goal is to produce a universal codec, which is one reason behind the open source move.

    The codec source code is licensed under dual MPL/GPL licenses.

    Dirac is modular, and thus well-suited to implementation with an object-oriented programming language. The reference engine is written in ISO Standard C++, and has been tested under various forms of 32- and 64-bit Linux, as well as under Windows 2000/XP.

    I'll try to answer questions here, to the best of my ability.

  • by hak1du ( 761835 ) on Friday April 30, 2004 @03:18PM (#9021622) Journal
    Perhaps even more impressive than the improved bit rates is that the source code actually looks competently written and is small. It also seems to use C++ in a reasonable way: to achieve just around the right amount of abstraction, without building a useless, general framework.
    • by ChaoticCoyote ( 195677 ) on Friday April 30, 2004 @03:27PM (#9021697) Homepage

      The framework is changing as we profile and analyze the code.

      Speaking for myself (independent of Dirac), the best C++ code is the simplest code. Just because a feature exists doesn't mean it must be used -- and conversely, just because a feature can be used poorly doesn't mean it should never be used. The goal is to use the right C++ features for the job, and avoid become lost in a nest of complex classes and templates.

      There's nothing about Dirac, BTW, that requires C++, or even object-oriented programming.

  • by tinla ( 120858 ) on Friday April 30, 2004 @03:24PM (#9021674) Homepage Journal

    Many people, esp our american friends, many not be familar with the sheer scale of the BBC's operation. There is a lot of dressing applied to their funding but in essence almost every UK home pays a BBC tax, giving them vast cash funds and allowing them to take a 'long term' view to development.

    This is very unpopular with their competition. People like Sky (NewsCorp) and ITV ('free' UK advert funded network tv) have no means of building the digital services the BBC have. Lets face it - both buy in a lot of programming from the US and that doesn't work well online.

    At a recent LINX meeting (a meeting of all the major UK ISPs and many of the major european ISPs) where the BBC gave a presentation about their 'Summer of sports' coverage. They are predicting up to 12Gbps (yes Gigabits) leaving their network during the olympics. This is a huge undertaking and requires them to put Gbps direct connections into the major UK ISPs such as BT. Without private peering of this type the BBC couldn't cope, LINX couldn't cope, the target ISP couldn't cope, it'd be meltdown all round. Their presentation was aimed at heading off a potential doom of them DOSing a major ISP into the ground.

    They're using Real at the moment. If they eventually move to an open codec the it will become a MAJOR player overnight. A national broadcaster using a codec to pump out Gigabits per second of content is the only case study/endorsement needed.

    I've not spoken to the techs pushing this within the BBC but the feeling I have from whitepapers, presentations and rumour are:

    - they need to be pragmatic. Its public money they're spending and the solution has to work. Currently the only solutions that work are propeirtary codecs.

    - They are under attack from the competition, who want to cut off their r&d funding which they see as unfair.

    - The intend to share their technology and want to grow the stability and performance through sharing things with their peers.

    For BBC network info (and a boatload of mrtg goodness) visit the ever popular support pages []
  • by oolon ( 43347 ) on Friday April 30, 2004 @06:36PM (#9023604)
    Water looked alot better, still had some problems with key frames ghosting arround sharp edges the picture improved after a few deltas. It was pretty neat however sound is still a problem ogg is not high fi enough so they are going to license something.