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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.""
How long before he'll be offered a juicy job at Microsoft or Apple???
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?
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" ...
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.
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.
'nuff said.
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";
lets -> let's
sentance -> sentence
It's late.
That's pretty cool; I didn't even know that BBC had programmers (other than their own TV and web coders, obviously). That's pretty cool. I suspect that the BBC will be releasing much of it's news on this codec... glad that my trusty old MPlayer will have it :)
- Code Dark
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.
...because it rhymes with Chirac.
The power of accurate observation is commonly called cynicism by those who have not got it. -- G.B. Shaw
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
"Life isn't about the number of breaths we take; it's about the moments that take our breath away. Like choking."
MWC
I think the Dirac project is fantastic and is a good example of public money being used for the public good.
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.
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.
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!
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.
Please help metamoderate.
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?
Anything to do with Paul Dirac ?
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
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.
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).
Please help metamoderate.
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.
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?" `":" #");}
This is a very big problem: major distros cannot include mplayer because of potential patent suits.
;P )
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
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.
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.
Please help metamoderate.
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.
I used tried and techniques, like wavelets, which weren't in standards at the time, and tried to develop them.
I thought they spoke good English in the Queen's land?! Is he not from the South of England?!
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.
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
Otherwise, I'm interested in a cheap (read: free) video streaming solution that would allow people to distribute the load ala streamcast or something, because I can't afford the bandwidth bill.
Buy Steampunk Clothing Online!
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.
You use the word open, but you don't know what it means.
I think what you're looking for is free-as-in-what-RMS-thinks.
Download the source code, compile as library. Use.
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?
Blibbler
Sorry for the double post, but it needs to be formatted properly
:-p )
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
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?
Come on. I though we were trying to get AWAY from such.
Also, I guess it's fine paying HUGE royalties for your beloved Apple codecs if you are a Mac fanboy. For me, that thing will never be used.
Nuff Said.
This is IMO the most likely scenario of what happened :
... of course the "management" would have gotten squat if they just liquidized everything, so they managed to con the remaining investors into going with Adams pie in the sky. Saving their own hides, realizing full and well it was all a scam.
We have a a gold prospecting company with remaining assets but no future
They say they are patenting aspects of Dirac and that the patent licenses will be valid for their use in Dirac for free.
For a GPL compatible license you need a license to use it for free for any derived project (in effect for any GPL project).
A judge/jury probably wouldnt be too happy with someone who releases software under the GPL knowing he will have patents covering it ... but there is nothing in the GPL which forbids doing that.
... so what the license contains is irrelevant to him as long as he abides by the license to the license, which is just :
The original author does not actually use the GPL when he releases his software, he needs no license to distribute
"Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed."
This is in essence a loophole in the GPL. Lizardtech did this with DjVu for instance (although I think they changed their tune). The license to the GPL should enforce patent licensing compatible with the GPL IMO. Yes it would complicate the license, but it needs to be done.
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
Okay I buffer say 10 frames from ffmpeg ... I want to output one once every 1/25 seconds.
... 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.
I output a frame, start decoding a new one to fill my buffer again
With a multithreaded implementation the OS would schedule an output thread, put up one of the frames from the buffer and retain smooth playback.
So the ffmpeg decoding speed determines when I output my frames, regardless of how many frames I have buffered. The only advantage is that getting back in sync with audio by dropping frames works better. You can stay in sync just easily with a single threaded implementation, but you cannot maintain the same fluidity.
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!
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
An interview with Dave Thomas? ...Oh, wait.
Spine World
Duh ! Ask Greg Dyke what he thinks about that, obviously the Government do try and stick there oar in now and again but equally obviously they do not have an easy time of it.
The BBC is funded by the licence fee which is not really a form of government taxation at all, there is a steering commitee who oversea the money is spent wisely.
Other UK networks, Channel 4 in particular do manage to do a good job and remain impartial but I think that's in part because they have to compete with the BBC, there is nothing like the dreadful rubbish which passes for news in the US.
Using the source, as in using Dirac? Or using source as in modifying it? Neither the question nor the answer is specific enough.
and from another post of yours on this thread.
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).
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!
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"
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!
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?" `":" #");}
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
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)
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...