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Interview With BBC Dirac Developer Thomas Davis

arclightfire writes "The subject of the BBC video codec Dirac has been here before, but we've managed to get an interview with Thomas Davies, Senior R&D Engineer at the BBC who devised the Dirac algorithm. Interesting to note that the codec should be with Mplayer soon; "As far as players go, we'll be submitting a patch to Mplayer to allow it to play Dirac pretty soon." And info about the tech developments in Dirac; "I used tried and techniques, like wavelets, which weren't in standards at the time, and tried to develop them. And that's what we'll continue to do as the algorithm develops. So we've tried to build on some pretty well-understood technology, and also tried to do some new things with it. We're patenting the new stuff, quite a bit of which hasn't got into the software yet. The license means that these patents are licensed for free within the Dirac software.""

111 of 170 comments (clear)

  1. Now... by Pig+Hogger · · Score: 1, Funny

    How long before he'll be offered a juicy job at Microsoft or Apple???

    1. Re:Now... by AliasTheRoot · · Score: 1

      why would he? ms and apples operations in the uk are primarily sales operations.

    2. Re:Now... by Kumkwat · · Score: 2, Insightful



      Microsoft Research lives at Cambridge. They would be very interested in innovative compression techinques.

  2. For Linux? by pimpius+the+impious · · Score: 1, Troll

    Will we have the same fiasco with no legal decryption for Linux, then prosecution for not buying a registered decryptor as we did with DVD? Or will we need another 6 lines of Perl?

    1. Re:For Linux? by lphuberdeau · · Score: 2, Informative

      RTFA

      They plan on releasing open source and submit a patch for mplayer themselves.

      --
      Qui ne va pas à la chasse n'a pas de gibier
      PHP Queb
  3. Great codec, awful name by YetAnotherName · · Score: 3, Funny

    Especially from a British developer ... I mean, he could've gone with something like "The Cybermen Codec" or "The Sontaran Codec" or at least "The Dalek Codec" ...

    1. Re:Great codec, awful name by savagedome · · Score: 2, Funny

      I would definitely take a suggestion for name from somebody whose id is "YetAnotherName". Yup.

    2. Re:Great codec, awful name by squarefish · · Score: 1

      'the codec of silly walks'

      --
      Creationists are a lot like zombies. Slow, but powerful and numerous. And they all want to eat our brains.
    3. Re:Great codec, awful name by strider44 · · Score: 1

      Or the Video Player's Guide to the Codec.

    4. Re:Great codec, awful name by AKAImBatman · · Score: 2, Funny

      "Always Look on the Bright Side of the Screen"

    5. Re:Great codec, awful name by Fallen+Andy · · Score: 5, Interesting

      Oh boy. You *are* ignorant. "Dirac" is the physicist
      who came up with the idea of anti-matter. Not only that but he did his Bsc at Bristol University. Yeah
      Bristol south-west of england.

      He didn't like it though. Don't know why, worked for
      me (splutters). I escaped that fine institution as
      a chemist (but I have spent far too many years playing with computers...).

      Bristol is also where the BBC has some of it's more
      interesting people, like the wildlife unit.

      Oh and Bristol Zoo. Which thanks to Alan Cox (cheers mate) used to have a penguin called Linus.
      If I wasn't stuck here in Rainy Athens (hey? I'm
      winding up the UK people ok..) I'd go kiss it right now.

    6. Re:Great codec, awful name by dillkvast · · Score: 1

      I realize of course that you are just making a joke. But the name is probably carfully chosen. Aside from Dirac being an important British physicist, the dirac delta function is a central element in signal processing theory. The dirac delta, normally denoted as a lowercase greek delta character, is defined as a pulse which integral is equal to 1. In addition the pulse duration approaches zero. For time descrete signal processing systems the dirac function is simply a unit value at time = 0.

      One important quality of the dirac function is that is contains a flat frequency spectrum. Given a causal, time invariant linear signal processing system (which most are, to an extent anyway), the response from an applied dirac pulse givs us the (unit-)pulse resonse. This response is the inverse fourier transform of the transfer function of the system, describing the systems behavior at any frequency.

      Of course it is not possible to apply a dirac pulse to any analog system such as an audio ampifier, as it is infinatly high and short. In the digital world however it is simply a single unit value, and the unit-pulse response is easily obtained.

      It is probably not a coincident that the d in the dirac logo is replaced by the greek delta letter used to denote the dirac delta function.

      --
      Scitne aliquis remedium potimum crapulae?
  4. Dirac's not the only new codec in the running by Frac · · Score: 5, Informative

    h.264 (now formally known as AVC, the video-equivalent of AAC) is maturing. Well, at least Ahead's Nero Digital implementation of h.264 is maturing. The marketing spin has it called Nero Digital, but it's fully h.264 compliant. And the results are impressive - beta testing shows comparable quality of XviD at half the bitrate.

    1. Re:Dirac's not the only new codec in the running by Anonymous Coward · · Score: 1, Informative

      Indeed, realtime compression using H.264 at HD resolutions was demostrated at IBC recently, it's a mofo in terms of hardware but I can rememeber when MPEG2 encoders needed to be chilled, "you can comprese a 270Mbps raw stream down to just 8-9Mbps" they cried in amazement, lol, 8Mbps, if only.

  5. Why bother? by JPyObjC+Dude · · Score: 5, Informative

    H.264/AVC is open and extremely powerful. Why bother with another protocol?

    From Apple Tiger h.264 page:
    Not only is H.264/AVC very efficient, providing extremely high quality in smaller files, but H.264/AVC is also scalable, producing video for everything from 3G for mobile phones to High Definition (HD). H.264/AVC can create great-looking 3G mobile content at 50-160 Kbps, excellent Standard Definition (SD) video at 800-1500 Kbps, beautiful HD video (1280x720, 24p) at 5-7 Mbps and full HD video (1920x1080, 24p) at 7-9 Mbps. So at today's SD DVD data rates, H.264/AVC can deliver full HD. In fact, H.264/AVC was ratified by the DVD Forum for inclusion in the next-generation HD DVD format.

    1. Re:Why bother? by damiam · · Score: 3, Insightful

      Open? So, can you use it commercially without a license fee?

      --
      It's hard to be religious when certain people are never incinerated by bolts of lightning.
    2. Re:Why bother? by Anonymous Coward · · Score: 1, Interesting

      Well, lets wait and see which is better, shall we?

      p.s. If I were you I'd have left off that last sentance...
      "H.264/AVC was ratified by the DVD Forum for inclusion in the next-generation HD DVD format"

      Because we all know how great MPEG2 is. And how much cheaper our HD-DVDs and players will be with mandatory WMV support. Those guys are clueless.

    3. Re:Why bother? by diracvideo · · Score: 1

      You can re-license Dirac under the LGPL. So you can use it royaly free in commercial software by dynamic linking to the binaries.

    4. Re:Why bother? by damiam · · Score: 1

      I was talking about H.264, not Dirac.

      --
      It's hard to be religious when certain people are never incinerated by bolts of lightning.
  6. Is it in M*ENCODER* by strredwolf · · Score: 4, Interesting

    Having decode support in Mplayer is good. but it's not going to fly well if there's no support for encoding! How are you going to use it to it's full potential in Unix if you can't back up your DVD's with it?

    It goes double for the Ogg Theora format.

    --

    --
    # Canmephians for a better Linux Kernel
    $Stalag99{"URL"}="http://stalag99.net";
    1. Re:Is it in M*ENCODER* by blowdart · · Score: 1
      And whilst a new codec with Unix support is nice, and encoding is nice, how may average listeners are going to download mplayer?

      Unless they produce a DirectShow filter for Windows (like ffdshow does for DivX), they're excluding that rather large desktop market of listeners. Their research page says they have volunteers to code the filter, but until that arrives the codec is playing to a very small audidence. (A bit like the BBC digital channels <g>)

    2. Re:Is it in M*ENCODER* by diracvideo · · Score: 5, Informative

      Both a C interface to our encoder and direct show filters are on our road map. Monitor our site or check freshmeat to find out as soon as they arrive. Please bear in mind we are only in alpha.

  7. H.264 is pricey even more than MS's WMV 9 by riversky · · Score: 5, Informative

    The license costs on H.264 are the most expensive on the planet (MPEG LA controls it with a hell of a lot of patented stuff from various companies). This is why it isn't being adopted rapidly. Even MS undercut it with cheaper licensing on Windows Media. This will kill it, a very nice technology. I am all for open source codecs. Perhaps BBC is on to something.

  8. US media won't use it by calculadoru · · Score: 1, Funny

    ...because it rhymes with Chirac.

    --
    The power of accurate observation is commonly called cynicism by those who have not got it. -- G.B. Shaw
    1. Re:US media won't use it by sploo22 · · Score: 1

      It's DIE-rac, not dih-RAC.

      --
      Karma: Segmentation fault (tried to dereference a null post)
    2. Re:US media won't use it by calculadoru · · Score: 2, Funny

      It's DIE-rac, not dih-RAC

      Sorry about that one then.
      I still don't think the US media will use it, because it rhymes with (the bizarre way they choose to pronounce) Iraq .

      --
      The power of accurate observation is commonly called cynicism by those who have not got it. -- G.B. Shaw
  9. Why not use OGG Theora? by solidhen · · Score: 4, Interesting

    From what I've read it looks like the goal with Dirac is to get a royalty free codec. If this is correct then why did you decide against using/contributing to the open source/open standard ogg theora codec?

    --
    Some things are more important than an animated rat
    1. Re:Why not use OGG Theora? by 42forty-two42 · · Score: 2, Insightful

      If the quality of Dirac is higher it should of course be preferred. That said, I have not seen any video encoded with either, except for that Java Theora implementation last week (?), so I don't know which one is better.

    2. Re:Why not use OGG Theora? by Anonymous Coward · · Score: 1, Insightful

      Theora isn't as good as XviD, which is MPEG4. This aims to beat both.

    3. Re:Why not use OGG Theora? by nileshbansal · · Score: 1
      Theora isn't as good as XviD
      How can you say that? theora can produce a smaller file with same quality.
    4. Re:Why not use OGG Theora? by julesh · · Score: 1

      For god's sake, this is answered on the FAQ page of the BBC Dirac site. Do some research before asking questions, or moderating them up...

  10. Re:No jokes about Wendys? by Resident+Maniac · · Score: 3, Funny
    No jokes about Wendys? What the hell, where are all the slashot humorists?
    In Soviet Russia, Wendy's jokes about Slashdot humorists! =P
    --
    "Life isn't about the number of breaths we take; it's about the moments that take our breath away. Like choking."
  11. They could at least write it with ResEdit! by Anonymous Coward · · Score: 1, Funny
    Like Adam recently did with his latest incarnation of Adam's Platform....
    ... or so he told his board yesterday!

    MWC

    I think the Dirac project is fantastic and is a good example of public money being used for the public good.

    1. Re:They could at least write it with ResEdit! by Anonymous Coward · · Score: 1, Informative

      [Posting anonymously because I know some of the people involved]

      Thank you to parent and grandparent. I've been following the Adams Platform/MWC saga for some time, but hadn't seen the most recent ASX document...

      Adam Clark and his father are total fruit loops. Quite a few big names (who should have had better-tuned bullshit detectors given their positions) got suckered by them but the smarter ones got out earlier when Adam refused to let even his company's own board independently review the technology.

      Frankly from what I hear about Adam's behaviour, they should have been asking pretty hard questions about his mental stability straight away...

      Now the Fraud Squad are investigating I'm really keen to see how he pulled off the scam! I know people who probably know how it was done, but I've so far had to play an annoying sort of "warmer/colder" guessing game with them as they're still bound by legal agreements.

    2. Re:They could at least write it with ResEdit! by mrpoppy · · Score: 1

      I too have been following the Adam's Platform saga for ages now. Remember the outrage when some journo from The Australian was championing this guy's cause as an Aussie Battler trying to make it in the big time? Despite the journalist receiving mountains of letters from some very smart people proving that Adam's claims could not be true, he still stood by him.

  12. Re:Dirac is free, H.264 is not by JPyObjC+Dude · · Score: 2, Interesting


    Licence snippet:


    In the case of the (a) encoder and decoder manufacturer sublicenses:
    For (a) (1) branded encoder and decoder products sold both to end users and on an OEM
    basis for incorporation into personal computers but not part of an operating system...




    I read that this applies to sold software not free software. Licence free for free (OS) software?

  13. Patents by Anonymous Coward · · Score: 3, Interesting

    Sounds like those patents are licensed for free within the context of this project, but not if you take the technology out of the codec. Fine, great, except that's the same license Microsoft offered on their SPF stuff, and they got drilled for it.

    1. Re:Patents by diracvideo · · Score: 4, Informative

      Dirac is licensed under the MPL (Mozilla) triple license. This means it is primariliy licensed under the MPL but anyone is free to re-license under either the GPL or LGPL licenses. We used the Mozilla license becuase it is well known and deals with patent issues. It means that any patents the BBC can license relating to the software are implicitly and irrevocably licensed for the software. So there are no royalties to pay for developing or using this software (either encoder or decoder). We chose this license to try to ensure that the codec remains royalty free. We figured if it was good enought for the Mozilla project it would probably be OK for us too. On the other hand we are aware that the MPL, on its own, is incompatible with the GPL and LGPL. We didn't want this and so have allowed re-licensing under the GPL. This means GPL software can freely integrate and develop Dirac. This is the approach suggested on the Gnu license page. You can also license Dirac under the LGPL. This means that even proprietary software can use it if they dynamically link with the libraries. The reason we have done this is so that the widest range of users can use Dirac royalty free.

  14. what? by squarefish · · Score: 3, Funny

    the BBC working with software?

    did they have anything to do with python?

    --
    Creationists are a lot like zombies. Slow, but powerful and numerous. And they all want to eat our brains.
    1. Re:what? by calculadoru · · Score: 1

      did they have anything to do with python?

      YES

      --
      The power of accurate observation is commonly called cynicism by those who have not got it. -- G.B. Shaw
    2. Re:what? by UserGoogol · · Score: 3, Funny

      Oh wow. I had absolutely no idea that there was once a comedy group named after the Python programming language. And in 1969! Those cats were ahead of their time.

      --
      "Never attribute to malice that which can be adequately explained by stupidity." -- Hanlon's Razor
    3. Re:what? by phaze3000 · · Score: 1
      Hey, they been doing this stuff for years.

      Only problem is, it's all written in BBC Basic.

      --
      Blaming GW Bush for the Iraq war is like blaming Ronald McDonald for the poor quality of food.
  15. Dang, now when they invent the FTL telephone... by argent · · Score: 5, Funny

    Dang, now when they invent the FTL telephone they won't be able to call it the Dirac Communicator, 'cos everyone will think it's some kind of MP3 player!

    Another SF classic (Cities in Flight) shot down by careless scientist types. Goldarn it!

  16. openness is hardly a concern to mplayer developers by SuperBanana · · Score: 3, Insightful
    Dirac is free, H.264 is not

    Bullshit. Every MPEG standard implementor is -supposed- to pay royalties. But I don't see any projects which support mpeg video and audio- doing so. I also don't see anyone chasing them down for the royalties. The general consensus is that if you don't make money off it, nobody will chase you down for the royalties; they're happy with the revenue stream from commercial software.

    Further, if you bothered to read up, you'd note that there's a reference implementation with downloadable source code, and documents on the (ahem) ISO standard.

    Also, listening to someone complain about proprietary technology and "openness" being a hinderance is pretty funny in the context of Mplayer, considering that the developers distribute codec packs consisting of commercial software (specifically DLL files) they're -not allowed to distribute- from Microsoft, Real, Apple, Intel, and many others. Dozens of proprietary video and audio formats are included.

  17. "licensed for free within the Dirac software" by Papineau · · Score: 4, Interesting

    Does that mean the license does not extend to other usages (besides in Dirac)?

    This could be problematic to include in Mplayer, as Mplayer is licensed under the GPL, and IIRC, there's a patent clause (clause #4?) in the GPL saying something along the lines of "if you license your patent for use in a GPL software, the license extends to all software derived from the first one, not only that first one".

    Is this a correct reading of the situation?

    1. Re:"licensed for free within the Dirac software" by Srin+Tuar · · Score: 1


      The fart that they intend to release it undor the GPL means that so long as you keep your derived code under the GPL youre fine.

    2. Re:"licensed for free within the Dirac software" by KjetilK · · Score: 1
      I had the same worry. Field-of-use provisions are incompatible with the GPL. So this was rather unclear. However, in TFA, they say clearly that:

      PC:In your FAQ you say that the license that Dirac is released under is Mozilla triple license (MPL), but also that, "...allows for relicensing under the GPL or the LGPL." Could you clarify this - does it mean that Dirac will only be under the MPL, but that others developing using the source could release their work as GPL?

      TD:Yes, they could do that.

      Seems pretty clear, so I wouldn't worry too much.

      --
      Employee of Inrupt, Project Release Manager and Community Manager for Solid
    3. Re:"licensed for free within the Dirac software" by diracvideo · · Score: 2, Informative

      Dirac is licensed under the MPL (Mozilla) triple license. This means it is primariliy licensed under the MPL but anyone is free to re-license under either the GPL or LGPL licenses. We used the Mozilla license becuase it is well known and deals with patent issues. It means that any patents the BBC can license relating to the software are implicitly and irrevocably licensed for the software. So there are no royalties to pay for developing or using this software (either encoder or decoder). We chose this license to try to ensure that the codec remains royalty free. We figured if it was good enought for the Mozilla project it would probably be OK for us too. On the other hand we are aware that the MPL, on its own, is incompatible with the GPL and LGPL. We didn't want this and so have allowed re-licensing under the GPL. This means GPL software can freely integrate and develop Dirac. This is the approach suggested on the Gnu license page. You can also license Dirac under the LGPL. This means that even proprietary software can use it if they dynamically link with the libraries. The reason we have done this is so that the widest range of users can use Dirac royalty free.

  18. Re:Interesting... by mikael · · Score: 2, Interesting

    It's obvious from the article that they have their own research programmers (they have their own R&D department. I used to see adverts for inhouse graphics programmers).

    They also sponsor quite a bit of university research projects. Probably the most important just now is virtual studios and automatic classification of video clips (automatically convert a video stream into a text description).

    --
    Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
  19. Re:openness is hardly a concern to mplayer develop by RiffRafff · · Score: 2, Insightful

    Also, listening to someone complain about proprietary technology and "openness" being a hinderance is pretty funny in the context of Mplayer, considering that the developers distribute codec packs consisting of commercial software...

    Which is legal in Hungary. Welcome to the internet, son.

    I can't help but wonder just how YOU came to know about them, you being such an upstanding citizen and all. Hmmm?

    --
    "I might have made a tactical error in not going to a physician for 20 years." -- Warren Zevon
  20. BBC Commitment to Open Standards by alib001 · · Score: 3, Insightful
    TD: I think the BBC has always had a very strong commitment to Open Standards...

    Yeah... a Real strong commitment.

    There's a list of excuses for their audio streams here. (No, you may not: cue / rewind / download the stuff the license payers paid to produce.)

    Hopefully they'll sort out their copyright / rights management issues and delivery by the time dirac comes out. Frankly, it couldn't make things worse.

    1. Re:BBC Commitment to Open Standards by koogydelbbog · · Score: 1

      > No, you may not: cue / rewind / download the stuff the license payers paid to produce

      i hadn't seen this before but always found it curious why they'd stopped that.

      from their FAQ:
      Unfortunately our rights agreements with the record companies mean that we cannot break music programmes up into smaller chunks, or offer a rewind facility.

      however, their html-based player just uses rpm (real) files. view-source, find the rpm file and use that in realplayer and you can rewind to your heart's content.

    2. Re:BBC Commitment to Open Standards by alib001 · · Score: 1
      however, their html-based player just uses rpm (real) files. view-source, find the rpm file and use that in realplayer and you can rewind to your heart's content.

      Yeah I do that sometimes but if I do I use Real Alternative an er... alternative to RealPlayer (Win).

      I just really object to jumping through hoops to listen to output that was paid for by the public. Also it's ridiculous that an organisation as large as the Beeb can't sort out their rights management. Practically, they're the only stations with national coverage and (last time I listened) they were rigidly adhering to set playlists on Radio 1, promoting the same ten or so songs throughout most of the day. Given this, if they can't negotiate useful terms then they should really stop taxing the great British Public.

      I'll believe the value of dirac when I see it in use. Cynics might say that projects such as dirac and the talk of access to the archives is directly linked to the expiry of the charter in 2006 and they've just woken up and realised they need to win public support.

  21. mplayer is bloated and going nowhere by SuperBanana · · Score: 1, Offtopic

    Who cares about mplayer support?

    It's bloated. On both linux and MacOS X, it consumes considerable CPU resources- and that's with the fancy interpolation it supposedly does turned off. My Powerbook G4, for example- mplayer consumes about 60% CPU, enough to bake my lap and turn on the fan after a while. VLC, on the other hand- needs about 20%, keeping my lap happy.

    I had a similar experience with Xine- it would take up only a few percent of my athlon's CPU time, but mplayer would practically throttle the system...and Xine supported on the fly variable speed playback(ala VCR jog control).

    Mplayer has been under "development" for several years. It hasn't seen any major or even minor feature additions. The user interface sucks, especially on OS X. For the most part, the only thing it can do is play video- on a very, very basic level; case and point, once it gets out of sync, it stays out of sync. About its only good quality is that its seeking is very fast and quite good- VLC's seeking sucks (takes forever, sometimes knocks video/audio out of sync for a few seconds- it recovers though, by scaling either the video or audio for a few seconds until they match again).

    1. Re:mplayer is bloated and going nowhere by Srin+Tuar · · Score: 1

      I dont use Mac hardware, but Ive had about the exact opposite experince.

      Some CPU intensive stuff I have been unable to play in anything but mplayer. (xin e and others couldnt keep up)

      futhermore, its the only thing ive been able to play matroska files in, so its the only choice really. if not for those things i would prefers xine's ui.

    2. Re:mplayer is bloated and going nowhere by 42forty-two42 · · Score: 1

      The times I've used VLC (on windows anyway, never used it on linux), the A/V resync caused a noticable change in audio pitch. I've never noticed such a pitch change in mplayer (though it does take a while to resync)

    3. Re:mplayer is bloated and going nowhere by erikharrison · · Score: 1

      mplayer has as part of it's arechetectural design to squeeze every frame it can out of the hardware. That's one of the reasons it's build process has historically been so complex, and the reason it has a strictly single threaded design (or at least did last I checked).

      mplayer plays just about everything, and is pretty ubiquitous. Xine has been in RC status forever now, and pulls in plenty of its codec work from mplayer anyway.

      mplayer is the bottom line for video playback on alternative OS's. Get it into mplayer, and it'll quickly spread to other players.

    4. Re:mplayer is bloated and going nowhere by 0x0d0a · · Score: 3, Informative

      Who cares about mplayer support?

      Those of us who prefer our keyboard to our mouse. And other folks.

      It's bloated. On both linux and MacOS X, it consumes considerable CPU resources- and that's with the fancy interpolation it supposedly does turned off. My Powerbook G4, for example- mplayer consumes about 60% CPU, enough to bake my lap and turn on the fan after a while. VLC, on the other hand- needs about 20%, keeping my lap happy.

      You misconfigured it. This is, admittedly, not hard to do, but mplayer is the fastest of movie players if used correctly.

      Try using the following command: mplayer -vo xv -fs=yes moviename.

      Hmm, upon checking the manual, perhaps if Mac OS X lacks support for xv you should be using -vo quartz.

      Mplayer has been under "development" for several years. It hasn't seen any major or even minor feature additions. /me boggles.

      You've got to be joking. What about the latest ChangeLog?

      The user interface sucks, especially on OS X.

      Actually, mplayer has some kind of bitmapped interface, which I always compile out. I hate all of those damned bitmapped interfaces, the pseudo-VCR things. It has a CLI interface which is exactly the same on OS X as on the other platforms.

    5. Re:mplayer is bloated and going nowhere by RJabelman · · Score: 1

      Sounds like YMMV then. On my PowerBook G4 (a 1GHz 12"), mplayer uses ~40% CPU and never turns the fan on in situations when I wouldn't expect the fan to come on.

    6. Re:mplayer is bloated and going nowhere by 0x0d0a · · Score: 1

      Actually if it was threaded it could probably run on even slightly lower end machines, you cant really buffer frames without multithreading ... a couple of slow frames get you into trouble fast with mplayer on formats which dont allow easy resyncing.

      That is absolutely absurd. You can buffer up as many frames as you want, and multithreading is completely irrelevant.

      Preemptive multithreading (at the program level, not the OS level) is, as everyone knows (at least until they actually write a significant quantity of multithreaded software and non-multithreaded software or write a server that actually, y'know, uses select()), is awesome. Then their earlier enthusiasm is replaced with the realization that:

      1) Multithreading doesn't let you do anything that single-threaded programs don't do.

      2) Multhreaded programs are really hard to profile well.

      3) Multithreaded programs are *incredibly* hard to debug. Just recently, I watched a (good, experienced) systems engineer that had built threading systems write a small (but crucial) system to demo his threads system -- with a nasty race condition. Incredibly hard. The number of ways you can screw up a multithreaded program is vast and numerous. Pan (the multithreaded GNOME newsreader) suffered from bugs for *ages*.

      4) There is one time that one uses multithreading. One does not use multithreading because it is necessary for latency. One uses it because it can make code structure simpler, mean that you don't have to remember the state of an ongoing operation. Multithreading hides the work of storing and resuming a task correctly in favor of the work of avoiding ordering problems in data interaction between tasks. As most experienced folks can tell you, storing and resuming is almost always a lot less work than avoiding race conditions.

      The problem is that for beginning programmers, blocking threaded APIs look so easy, so seductively simple (I just call "SendFile()" in my FTP server, and when the call returns, I'm done sending the file!") They don't factor in the costs that slink along with threading.

    7. Re:mplayer is bloated and going nowhere by 0x0d0a · · Score: 1

      (though it does take a while to resync)

      See the mplayer man page:

      -mc
      Maximum A-V sync correction per frame (in seconds).

    8. Re:mplayer is bloated and going nowhere by pcardno · · Score: 1

      "Try using the following command: mplayer -vo xv -fs=yes moviename."

      Aha, very intuitive... Yikes!

      --
      --- Band: Joey Ultra
    9. Re:mplayer is bloated and going nowhere by Mosu · · Score: 1

      Both xine and vlc have fine support for Matroska in general. Even gstreamer based apps should be fine. One problem might be that vlc doesn't use non-(L)GPLed codecs so you can't play Matroska files with RealVideo inside, and RV seems to be one of the most used codecs with Matroska.

    10. Re:mplayer is bloated and going nowhere by 42forty-two42 · · Score: 1

      It usually doesn't go out of sync for me, except with really low quality .mpeg files when seeking (or correcting for corruption), so I don't bother.

    11. Re:mplayer is bloated and going nowhere by 0x0d0a · · Score: 1

      -vo xv would normally go in your config file.

      And I lied -- it should be -fs, not -fs=yes.

      That's just the same as hitting "f" to fullscreen the movie.

      So I have vo=xv and fs=yes in my config file, and don't have to worry about it. It's covered in the docs.

  22. What happened to BitTorrent plan? by peteryorke · · Score: 2, Interesting

    What happened to BitTorrent plan for delivery of all the BBC archives? Wasn't it in August 2003 of last year that the BBC said it was going to deliver all of it's audio and video archive via Bit Torrent? I want all my BBC content online for download. When's it gonna happen or is this just more BBC pie in the sky R&D fluff.

    1. Re:What happened to BitTorrent plan? by Anonymous Coward · · Score: 1, Informative

      From what I hear, it is being tested with around 1000 users right now. Its not just the archives though - its part of a larger project to have a 'Listen Again' (which was for radio) style system for TV.

    2. Re:What happened to BitTorrent plan? by Insipid+Trunculance · · Score: 1

      any news /links you could point us to?

      --
      Wanted : A Signature.
  23. Re:openness is hardly a concern to mplayer develop by Spy+Hunter · · Score: 3, Insightful

    Yeah, it's all fine for now. But building free software on a proprietary base will bite you in the ass in the long run (which is why we have the Debian project, but that's a topic for another time). Eventually someone will make a program that the MPEG people don't like (such as an easy converter to Dirac), and they will get sued into next week. Or, if the open-source codecs are sucessful and become the de-facto standard for multimedia, THEN they'll start being pricks about the royalties. The MPEG consortium can come in at any time they like and destroy any open-source project using their standards, or leech off their hard work by charging everybody royalties. I wouldn't work on a project that had that hanging over its head, even if the MPEG people have been okay so far.

    --
    main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
  24. Re:openness is hardly a concern to mplayer develop by Srin+Tuar · · Score: 2, Insightful

    This is a very big problem: major distros cannot include mplayer because of potential patent suits.

    Just because noone has filed suit yet means nothing.

    If you want desktop linux to have a chance there have to be popular patent-free multimedia formats that it can use.

    There really is no point in promulgating any more mental-prison ware than strictly necessary. When new codecs are being developed, it only makes sense to throw your support behind the free ones when you have a choice.

    (iow, Dirac + ogg in an mkv container could save your soul ;P )

  25. but when.. by Turn-X+Alphonse · · Score: 2, Insightful

    Do we get a government based report looking into it and decicing it's a waste of the licence fee money then kill it?

    The BBC is funded by people paying a licence to watch TV in the UK (it is illegal not to have one and watch TV in your place of residences). Now 99% of these people arn't geeks and won't use a codec, why are they paying for it?

    --
    I like muppets.
    1. Re:but when.. by trewornan · · Score: 4, Insightful
      Now 99% of these people arn't geeks and won't use a codec, why are they paying for it?

      Because in the future they will be using it (or something like it) and if the BBC don't sort something out right now - in ten years time we'll all be needing Microsoft's permission to view what their PR department doesn't object to.

    2. Re:but when.. by RichardX · · Score: 1

      The BBC is funded by people paying a licence to watch TV in the UK (it is illegal not to have one and watch TV in your place of residences).

      Just wanted to point out the parent is being a little misleading here (unintentionally, I think) - from that it sounds like it's illegal NOT to watch TV in the UK.. rather a chilling 1984-esque concept.. families gathered round the TV set, guns to their heads, beads of sweat forming on their brows as they concentrate intently on soap operas and gameshows, not daring to blink..

      um, but I digress.. the actual state of play is that if you have a television set in your house at all, even if you don't use it to watch TV, you HAVE to pay an annual TV licence fee - just the one fee no matter how many tellys you have, mind, but auntie (the BBC) will not be cheated.. they even send out people in detector vans to find people who don't pay their licence - and no foil hat will save you from that.

      --
      Curiosity was framed. Ignorance killed the cat.
    3. Re:but when.. by stiggle · · Score: 1

      Actually - the license is for the reception of TV signals. So PC TV-tuner cards and such are also required to have a license even if you don't have a TV.

      You can own a TV and not pay the license fee - if you can clearly show that the TV receiver is not used. (eg - detuned with no plug and ariel attached and its in a the bottom of a locked filing cabinet in a disused lavatory with a sign on the door saying "Beware of the Leopard")

      When I stopped watching TV - I gave the TV away to a friend and put the video recorder under the back seat of the car with no plug, before eventually giving that away too.

      They stopped sending me letters demanding I pay them when I pointed out that sending offensive threats through the post is in fact illegal in the UK.

      (I've now moved house and am paying the license fee again seeing as I have a TV)

      A lot of technology comes out of the BBC - its not just a media broadcaster.

    4. Re:but when.. by Bertie · · Score: 3, Insightful

      It's all part of the BBC's remit. It was the BBC that developed NICAM, for instance. The BBC took it upon themselves to encourage the takeup of home computing by coming up with the spec for their own machine and recruiting Acorn to make it. Their Internet presence has been a major factor in getting the British population online - the BBC's websites are now among the most popular in the world. And they're currently at the forefront of the push to get digital TV into every home in the country through their Freeview set-top boxes.

    5. Re:but when.. by GMHobbit · · Score: 1

      I'm now living in Australia (moved from the UK 18 months ago) and I can tell you that the BBC License fee is WORTH EVERY PENNY. If I could get that content over here, I'd pay a lot more that 130 quid a year.

    6. Re:but when.. by mantera · · Score: 1


      The BBC is funded by people paying a licence to watch TV in the UK (it is illegal not to have one and watch TV in your place of residences)

      Oh Boy! You mean it's illegal to watch TV and not have one!

  26. "legal in hungary" does not change anything by SuperBanana · · Score: 1, Flamebait
    Which is legal in Hungary. Welcome to the internet, son.

    The original poster said "H.264 is not free", implying that's why it shouldn't be implemented in mplayer.

    Further- just because it's legal in Hungary doesn't mean it is legal anywhere else- which is why mplayer isn't distributed with, for example, Debian. I don't believe it is, in fact, distributed with any major Linux distribution.

    I can't help but wonder just how YOU came to know about them

    I judge them by how they speak and represent themselves. They were total assholes about distros distributing binaries of mplayer, as well as compiler problems- they're such bad coders, their shit broke faster than a piece of china near a bull, and they would happily point a finger anybody they could. "Oh, the software crashes because Redhat didn't build it properly". Or, "oh, you didn't compile it with this one specific version of GCC." Except most of the rest of the world seemed to do pretty OK whenever a new version of GCC rolled around; everyone else's problems seemed to be "my stuff doesn't compile because gcc no longer likes that technically-invalid-but-previously-forgiven practice". Mplayer's problems always seemed to be "mplayer crashes when built with anything but this version of GCC".

    I also remember some very nasty "news items" posted on the mplayer website amounting to a flame war over licensing issues.

    1. Re:"legal in hungary" does not change anything by ncc74656 · · Score: 2, Informative
      Further- just because [MPlayer]'s legal in Hungary doesn't mean it is legal anywhere else- which is why mplayer isn't distributed with, for example, Debian. I don't believe it is, in fact, distributed with any major Linux distribution.

      There is a Gentoo ebuild for it. The MPlayer files (source and DLL packs) aren't hosted by any of the Gentoo mirrors, but are retrieved from the MPlayer website. The same applies to most software for which ebuilds exist, though. Source for GNU programs gets pulled from GNU mirrors, source for SourceForge-hosted projects gets pulled from SourceForge mirrors, etc. Whether you could call this state of affairs "distribution" is open to debate, I suppose. While what Gentoo provides directly is in a sense little more than instructions and a patchfile, installing MPlayer is no more difficult than installing Emacs or KDE.

      (It's worth mentioning that system-specific optimizations (-march=athlon-xp, or whatever) are disabled in the MPlayer ebuild, which goes against one of the main reasons people use Gentoo. With that said, it's behaved reasonably well IME.)

      --
      20 January 2017: the End of an Error.
  27. no. Here's why. by don.g · · Score: 2, Informative

    mencoder at present (AFAIK) only outputs AVI, a format which doesn't cope well with VBR.

    Until it supports the ogg bitstream format, you're not likely to see Vorbis audio support, let alone Theora.

    --
    Pretend that something especially witty is here. Thanks.
  28. Warez codecs are holding back free multimedia by Wesley+Felter · · Score: 2, Insightful

    You're completely right; such a lax attitude towards copyrights is a big barrier to the adoption of free (as in legally free) multimedia formats and software. Free software developers who don't respect Microsoft, Real, Apple, and Intel's copyrights shouldn't expect much in return.

    Given the Dirac developers' attitudes, I would expect them to be more likely to contribute to legal multimedia frameworks like GStreamer or Helix. Maybe the point of Dirac/Mplayer integration is popularity at any cost, in which case the cost will be a semi-underground existence.

    A reference implementation and ISO standard doesn't do me (or Fedora or Ubuntu etc.) much good; it's still patent-encumbered and thus not free.

  29. network television by Doc+Ruby · · Score: 5, Funny

    The BBC has an R&D department that builds video codecs. In the states, we've got PBS which makes a new muppet every 10 years, and ABCNNBCBS, which came up with projecting a yellow bar across the football scrimmage line in the 40 years since introducing color TV. That's why America is leading the media revolution!

    --

    --
    make install -not war

    1. Re:network television by isorox · · Score: 1

      That R&D department (a black box which you pour money in and get cool toys out) is possible because of the £120 a year fee every household in the UK has to pay.

    2. Re:network television by Singletoned · · Score: 2, Insightful
      That R&D department (a black box which you pour money in and get cool toys out) is possible because of the £120 a year fee every household in the UK has to pay.

      Which is a good thing, let's be clear.

      The value for money we get is good, but is secondary to the fact that it means we can get intelligent and impartial television and radio. Our friends in the US have nothing remotely like Radio 3 or 4. (High-brow classical music and jazz played in full, not just the famous bits, and high-brow, impartial current affairs, drama and comedy). They don't even have any politically impartial major broadcasters.

      In America most major stations are heavily right-wing because they are all owned by rich people who, unsurprisingly, support the Republicans. We get at least half a chance of hearing things from a reasonably independent, though critical, source.

      Worth every penny if you ask me, and I don't even watch TV.

    3. Re:network television by Bertie · · Score: 1

      Indeed. As long as we have a BBC, we'll never have a Fox News (leaving aside the fact that Fox News is available on satellite - what I mean is there'll never be a local version). They'd never get away with it. It'd just look ridiculous.

    4. Re:network television by pete-classic · · Score: 1

      Because they haven't awakened and had their revolution yet.

      Think about it; they have a monarchy, and they like it.

      -Peter

    5. Re:network television by isorox · · Score: 1

      Worth every penny if you ask me, and I don't even watch TV.

      You dont watch TV, but you have a TV license?

    6. Re:network television by Doc+Ruby · · Score: 1

      That's because you have a selective tax applied as a use fee. In the US, our PBS gets $670M:y from taxes, which is only about $2.25:person. But that's about $6.50:taxpayer. Still small, but that's because we spread the load across all taxpayers. The BBC taxes $3.9B on 24.1M people, for about $160:taxpayer. Still 6x the US tax rate on the taxpayers, but the BBC runs 8 channels, 44 radio stations, and broadcasts globally. In the US, PBS operates at most one channel in the cities in which it broadcasts, although some regions overlap, especially on cable. So the cost per channel per taxpayer (ignoring radio) is actually lower for the BBC, despite PBS tightening its belt under Republican pressure. And the BBC produces much more original programming (some of which PBS syndicates), as well as those radio stations. So the BBC is actually a better deal for its ratepayers, with a more fair fee basis based on consumption. And it also manages to advance global "television" technology, which PBS hasn't since the rubber Big Bird suit.

      --

      --
      make install -not war

    7. Re:network television by Singletoned · · Score: 1
      You dont watch TV, but you have a TV license?


      I use a TV for my games consoles and to watch DVDs. Plus my girlfriend watches TV.

    8. Re:network television by isorox · · Score: 1

      I use a TV for my games consoles and to watch DVDs.

      Which you dont need a license for.

      Plus my girlfriend watches TV.

      Ahh, women. Costly things. Fortunatly I've only got one myself.

  30. Re:openness is hardly a concern to mplayer develop by Spoing · · Score: 3, Insightful
    1. Bullshit. Every MPEG standard implementor is -supposed- to pay royalties. But I don't see any projects which support mpeg video and audio- doing so. I also don't see anyone chasing them down for the royalties. The general consensus is that if you don't make money off it, nobody will chase you down for the royalties; they're happy with the revenue stream from commercial software.

    Good point. One for you: Do you think the BBC will have to pay royalties if they use H.264?

    --
    A firewall can not protect you from yourself. Turn off what you do not need. Do not use the firewall to do your work.
  31. Re:openness is hardly a concern to mplayer develop by blibbler · · Score: 4, Informative

    Sorry for the double post, but it needs to be formatted properly

    Dirac + ogg in an mkv container could save your soul

    I assume you mean Dirac + Vorbis in Matroska... Ogg is a container format like matroska... (what you said was akin to DivX + AVI in ASF :-p )
    On a related topic, Matroska is an unfortunate format to use. It is very inefficient, both in CPU time, and in overhead. My computer can play a 640x480 divx in an avi, but can't play a 512x384 divx in matroska. Additionally, matroska has a higher file overhead than asf or quicktime.
    Ogg is a good, basic format. It could be seen as a sturdy replacement for AVI. Matroska doesn't do anything beyond even the Quicktime format... and quicktime is vastly more efficient.

    Anyway, moving on from that rant. I agree strongly with your other points. If you have a choice between two, largely equivalent codecs, one is unencumbered by laws and one is, why would you choose to use the one that is. Sure you might not get sued straight away, or even for a year or two, but why bother with that risk at all?
    I am not particularly bothered with pirating certain commercial software, but if there is a free program that does everything I need, I will use that over a pirated of a commercial program. Why take the risk when there is another option?

  32. Re:Interesting... by RichardX · · Score: 1

    Probably the most important just now is virtual studios and automatic classification of video clips (automatically convert a video stream into a text description).

    I've already developed a solution to that!
    My licence fees are very reasonable if you want to use it.. here's some sample output from a test run:

    Video file: TestMovie.AVI
    Description:
    First frame, first line:
    Grey pixel, grey pixel, slightly darker grey pixel, green pixel, greenish-grey pixel, black pixel,.... next line: grey pixel, orange pixel... etc

    --
    Curiosity was framed. Ignorance killed the cat.
  33. Re:openness is hardly a concern to mplayer develop by DrSkwid · · Score: 2, Insightful

    mencoder is a simple movie encoder, designed to encode MPlayer-playable movies to other MPlayer-playable formats. It encodes to DivX4, XviD, one of the libavcodec codecs and PCM/MP3/VBRMP3 audio in 1, 2 or 3 passes. Furthermore it has stream copying abilities, a powerful plugin system (crop, expand, flip, postprocess, rotate, scale, noise, rgb/yuv conversion) and more.

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  34. R&D????? Mr Blobby??? by SenseiLeNoir · · Score: 1

    Erm.... the BBC brought us Mr Blobby, which is itself enough to shoot it!!!!

    Wonder how much R&D that took!!!

    PS. I love the BBC, the above is a JOKE

    --
    Have a nice day!
    1. Re:R&D????? Mr Blobby??? by Doc+Ruby · · Score: 1

      And the Hitchhiker's Guide to the Galaxy, which is enough to get it to shoot us, take over the world, then shoot itself.

      --

      --
      make install -not war

  35. Version 0.4.3 out soon by tj_davies · · Score: 1

    If you're downloading the software to check it out: we're hoping to get Version 0.4.3 out in the next couple of days. This has much better constant quality encoding, and I think the performance is beginning to approach what we hoped for from the tools. Ultimately there's no reason why we can't do as well (or better, at high resolution at least ) as H264/AVC. But I would say that ... We're in the process of defining the bitstream syntax too, and we'll have a doc out in a few weeks. This will just be syntax, not decoder semantics, but it will cover additional tools that we want to put in the codec. Thomas Davies

  36. Dave Thomas? by Inuchance · · Score: 1

    An interview with Dave Thomas? ...Oh, wait.

  37. The FAQ states... by Kristoffer+Lunden · · Score: 2, Informative
    What about Ogg Theora?

    We're glad that it looks like Theora will reach beta soon. We think you can't have too many free codecs, but that the Open Source community also needs to continue to develop codecs with increasingly better performance. We also think there could be a good deal in Theora that we could use in Dirac, and we'd like to work with developers who've been closely involved in Theora. We intend to pack the Dirac elementary stream into MXF, which has lots of useful features. That doesn't preclude it packing into Ogg as well, and it's probably a good idea to have a variety of packing formats. For this the elementary stream needs to be very well defined.

    http://www.bbc.co.uk/rd/projects/dirac/documentati on/faq.htm#11
    1. Re:The FAQ states... by dolmen.fr · · Score: 2, Informative

      For those who, like me, wanted to know more about MXF, it is the Material eXchange Format (and not "Multimedia Exchange Format" as Thomas Davies said in the interview).

  38. MPlayer and Debian status... by Comsn · · Score: 1
    from http://www.debian.org/News/weekly/2004/12/ ...

    Towards an MPlayer Resolution. Diego Biurrun posted an update on the work being done to resolve MPlayer's licensing difficulties. The main two concerns have been the lack of a LICENSE file and noncompliance with clause 2a of the GNU General Public License, which Diego has attempted to address through a LICENSE file and a Copyright file. Don Armstrong thought it would suffice for Debian's purposes, but suggested that the MPlayer team should indicate in the relevant files that they've been changed and who changed them.


    and from another post of yours on this thread.
    They were total assholes about distros distributing binaries of mplayer, as well as compiler problems- they're such bad coders, their shit broke faster than a piece of china near a bull, and they would happily point a finger anybody they could. "Oh, the software crashes because Redhat didn't build it properly". Or, "oh, you didn't compile it with this one specific version of GCC."


    the problem really is the gcc, it will crash with an 'internal compiler error' , how can you blame MPlayer for that? all is well with a gcc upgrade (most of the time).

    Mplayer's problems always seemed to be "mplayer crashes when built with anything but this version of GCC".


    i havent seen this error, but then again i've only been helping people with mplayer for a year or so... if anyone needs help there are lots of users and even developers at #mplayer on irc.freenode.net , the mplayer devs have really stopped flaming people, from what it was like before. anyone still dualbooting be sure to check out the win32 cygwin or mingw ports of mplayer!
    http://mplayerhq.hu/MPlayer/releases/win32-beta/

    be sure to watch ffmpeg/mplayer for new codecs named 'snow' and 'sonic' and thier' container format 'NUT' , the ffmpeg and mplayer developers figure if everyone can make a codec and container, they can too, and they can do it better than anyone!
  39. when a licence is needed (& good for Dirac!) by feepcreature · · Score: 2, Informative
    No it isn't, it's illegal to watch the BBC without paying for it. If all you use your television for is console games or other channels, don't tune your television in to receive BBC channels and you will be fine.
    The actual rule is that if you operate equipment that is capable of receiving broadcast TV signals you need a licence (UK spelling :-) ), or you have to license it. Even if you only watch commercial TV, or you never turn it on, or you only watch videos or play games (honest, guv).

    There are minor exceptions for small, battery-only devices in caravans, and the like, and people have escaped where they could show that they could not receive broadcasts (like there was no aerial for their TV/Video, and neither were tuned in to TV channels), but it's not easy.

    And the rules on multiple-occupancy are complex, and the way the BBC seeks to apply them seems to evolve. But the basic idea is that you need a licence if there are any tellies in a house.

    It's enforced by automatic reminders, detector vans, £1000 fines (Grand if you have a licence, a grand if you don't), and TV sellers notifying the authorities when they sell a telly.

    In my opinion it's great value, though. Even if it is being dumbed down, and the free internet-accessible archive seems to have stalled somewhere...

    But developing a codec is sensible if it keeps the costs of streaming down - and especially if it's easier to implement on Open Source O/Ss. Hopefully some penny-driven accounting type at the Beeb won't feel the need to charge huge licence fees or impose Open-Source-incompatible licence terms.

    --
    Paul "Say no to feeping creaturism"
  40. Re:Interesting... by mikael · · Score: 2, Funny

    That's the easy bit :)

    Your mission, if you decide to accept it, is to catalogue 80,000 hours worth of pixel colours in movies and video so it can be searched by location, actors, presenters, producer, camera operator, sound operator, objects, clothes, sky, clouds, landmarks, time, direction, events, astronomical, geological, geopolitical events, age and anything else that a producer may want on a whim at 5.30pm, 30 minutes prior to presenting the evening news.

    --
    Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
  41. PBS and technology by PCM2 · · Score: 1

    Actually, PBS has been ahead of the curve on digital broadcasting here in the U.S. It was the first network to do a national broadcast of a program fully produced and aired in hi-def. It was also the first to offer a 24/7 network of HD programming. In addition, it has worked to develop applications for interactive TV, and has worked to build various advanced broadcasting technologies. PBS.org is the most-visited .org Web domain in the world. So in a nutshell you're, like, wrong. PBS has decades of leadership in broadcast technology. But I know everyone loves to knock it, so go right ahead.

    --
    Breakfast served all day!
    1. Re:PBS and technology by Doc+Ruby · · Score: 1

      I love PBS, it's the best TV network in the country, and raised me and millions of other American kids pretty well. But not for its R&D. Paying some American companies to build its intranet, and some other companies to install digital broadcast systems, makes it a great technology *customer*, which is valuable. As is its indispensible broadcasts of BBC's _Monty Python's Flying Circus_. But that isn't spending my tax dollars on the "Ministry of Silly Walks" budget, which is the comparison I made to the British poster.

      --

      --
      make install -not war

  42. Re:openness is hardly a concern to mplayer develop by Spy+Hunter · · Score: 1

    Why did you reply to my post with this? I am aware of MEncoder. Are you saying that it converts H.264 to Dirac? I have no doubt that it will eventually. However, it could hardly be called "easy". It is not incredibly complex, but it is a command line program, which immediately eliminates the possibility of it becoming very popular with nontechnical users. And I have no doubt that if Dirac threatens to surpass H.264 in popularity, and MEncoder is a popular way to transcode H.264 to Dirac, then the MPlayer team will get sued, or at least the distributors of MEncoder will get sued.

    --
    main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
  43. Re:Only half right by 0x0d0a · · Score: 1

    I output a frame, start decoding a new one to fill my buffer again ... and after 1/25 seconds I do what again if ffmpeg isnt finished yet? I wait that is what I do if Im single threaded.

    You save state, slap the frame up, and resume decoding.

    With a multithreaded implementation the OS would schedule an output thread, put up one of the frames from the buffer and retain smooth playback.

    With a multithreaded implementation, the OS does some of the work. The OS is a general-purpose OS and until recently had latencies causes serious issues with real-time things like sound work. It has no idea what kind of latency you require, what work should be done first, or anything of that nature.

    You can stay in sync just easily with a single threaded implementation, but you cannot maintain the same fluidity.

    You certainly can. You just have a do_pending_decoding_work() function that returns after a maximum amount of time instead of a decode_one_frame() function.

  44. Re:openness is hardly a concern to mplayer develop by DrSkwid · · Score: 1


    Eventually someone will make a program that the MPEG people don't like (such as an easy converter to Dirac)

    mencoder, with mpeg and dirac codecs should be able to do just this.

    it is a command line program, which immediately eliminates the possibility of it becoming very popular with nontechnical users

    don't believe the hype

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  45. Re:openness is hardly a concern to mplayer develop by Srin+Tuar · · Score: 1

    A bit long in responding, but yes I meant vorbis.
    And I like matroska because of its thorough unicode support for non-english languages in subtitles and menus etc.

    However, perhaps some implementations of it may be slow, I think thats just an implementation detail. (I havent been able to observe any significant difference on my system)

    And allthough OGM does look like a decent replacement for AVI in some ways, I dont think its all there, especially wrt to utf-8 support. (the ogg people seem to agree with that)

  46. Re:Usable? by trick-knee · · Score: 1

    > (Note: The following is publication, and may act as prior art to any future patent on this issue.)

    and so you post anonymously?

  47. Re:openness is hardly a concern to mplayer develop by blibbler · · Score: 1

    I didn't think of uni-code... that is a very valid point

    re: speed... I am not sure what you mean by "some implementations"... as far as I am aware, there is really only one implementation... The matroska people argue that a 10% (or however much it is) speed hit won't be significant in the long run, as computers get faster and faster. My computer is a relatively old one, which would explain why it can't handle matroska very well... but in any case, I have to wonder about the software produced by a group with such a philosophy.

    OGM is not the same as Ogg... it's a long story, and isn't particularly interesting... and isn't even that relevant as they are both derived from the same source... but I digress:
    I consider ogg to be an avi replacement, because both formats excell in being very simple. AVI and Ogg don't try to do much at all... which makes them relatively easy to fully support... in contrast, matroska, quicktime, real, and mp4 try to do everything... which results in lots of groups implementing only parts of the formats... of course, avis simplicity has gotten it into trouble... by people breaking the format to do crazy stuff inside it... I am mainly thinking of the two channel avis... not to mention the vbr mp3 AVIs...