Slashdot Mirror
More On The BBC's Codec 'Dirac'
TioHoltzman writes "El Reg is reporting about a new codec that is built on top of wavelet technology and seems to offer performance that is "roughly in line with the Video Codec 9" from Microsoft. The project has been released as open source on SourceForge. This looks like it might be really interesting." (Previously mentioned a few weeks back.)
Call me a zealot, but I think things are better off open source, doubly so in the case of codecs. I mean, it's a media encapsulation. If a codec is open, then the potential for cross-platform success is much better. Potential for profit may go down, but I'm talking innovation, not wallets.
Only the purest of souls seek enlightenment. Everyone else just wants power.
Does adding a little note saying "we covered this a few weeks ago" always get the editors off the hook for posting the same article twice? ;)
Am I the only one who thinks that Dirac sounds like some sort of monster from the Dr. Who series?
BLING BLING. Meet the architecture that's changing everything.
BBC to Put Entire Radio & TV Archive Online
Spam Vikings await.
The standard way to compress both audio and video is with the Discrete Cosine Transform, or DCT. MPEG audio and video are based on DCT.
The basic idea of DCT is to transform the data into a series of waves, which tends to concentrate the data. Then you throw away part of the data, and then use lossless encoding on what is left. If you just threw away pixels, the result would be obvious in an image; but if you throw away part of the wave specification data, the results are not as obvious.
With DCT, consistent data sets compress very well (e.g., a blue sky or a white wall). Pictures with lots of sharp little edges (e.g., a field of blades of grass) compress much less well.
My understanding is that potentially wavelets will compress even better than the DCT. However, they are not enough better to be a huge win at the moment.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
as for wavelet compression being a novel codec, what about apple's pixlet technology?
Some drink at the fountain of knowledge. Others just gargle.
But the BBC isn't the government - it's public service broadcasting at its best (though it's not as good as it might be, since it feels the need to justify the license fee by playing the ratings game and filling the schedule with mindless drivel). The BBC has been at the forefront of broadcast engineering development since the 1920s, and I'm happy to see them contributing to the world once more.
And the top rate of income tax over here isn't 50%, it's 40% - I wish it was 50% for high earners, then perhaps they'd have less disposable income to push house prices beyond the reach of the rest of us.
oh brave new world, that has such people in it!
(This is an excerpt from the book 'Surely You're Joking, Mr. Feynman!' and is for everyone here who has, or hasn't, heard of Paul Adrien Maurice Dirac, the namesake of this new codec. It also conveniently fits in with the two articles about Japan that made their way onto Slashdot today.)
..."
While in Kyoto I tried to learn Japanese with a vengeance. I worked much harder at it, and got to a point where I could go around in taxis and do things. I took lessons from a Japanese man every day for an hour.
One day he was teaching me the word for "see." "All right," he said. "You want to say, 'May I see your garden?' What do you say?"
I made up a sentence with the word that I had just learned.
"No, no!" he said. "When you say to someone, 'Would you like to see my garden?' you use the first 'see.' But when you want to see someone else's garden, you must use another 'see,' which is more polite."
"Would you like to glance at my lousy garden?" is essentially what you're saying in the first case, but when you want to look at the other fella's garden, you have to say something like "May I observe your gorgeous garden?" So there's two different words you have to use.
Then he gave me another one: "You go to a temple and you want to look at the gardens
I made up a sentence, this time with the polite "see."
"No, no!" he said. "In the temple, the gardens are much more elegant. So you have to say something that would be equivalent to 'May I hang my eyes on your most exquisite gardens?'"
Three or four different words for one idea, because when I'm doing it, it's miserable; when you're doing it, it's elegant.
I was learning Japanese mainly for technical things, so I decided to check if this same problem existed among the scientists.
At the institute the next day, I said to the guys in the office, "How would I say in Japanese, 'I solve the Dirac equation'?"
They said such-and-so.
"OK. Now I want to say, 'Would you solve the Dirac equation?' -- how do I say that?"
"Well, you have to use a different word for 'solve,'" they say.
"Why?" I protested. "When I solve it, I do the same damn thing as when you solve it!"
"Well, yes, but it's a different word -- it's more polite."
I gave up. I decided that wasn't the language for me, and stopped learning Japanese.
Nothing to do with the government. The BBC is granted a charter from Parliment, but is not government run or funded. The BBc is funded by a compulsory license fee for owning equipment capable of recieving and decoding their broadcasts such as a TV or tuner card. Basically it's a tax on virtually every household and business in the UK. There is a discount for black & white TV's, pensioners and those with vision based disabilities. In the 'old days' you used to need a 'wireless licence' as well for radios!
Pixlet is designed for real-time editing, so it has minimal artifacts and no interframe compression. Dirac is for broadcast, so it is much more agressive about compression and can take advantage of motion compensation and other computationally expensive compression techniques.
You are right, however, that wavelets are not at all a new compression technology. People started playing with it at least 10 years ago and JPEG-2000 uses wavelets for still photo compression. I think that the computational load has prevented their use in video until recently.
Most of them patent's will be in the US. So they don't matter. No offence to our american cousins on the 'dot, but you so often hear about "this is illegal under the DMCA" or "The've been granted a pantent from the USPO for this" or "The RIAA will come and take your first-born for this" or "The FBI will be busting down your door under the Patriot Act right about now...". It doesn't matter if they have got 'rights' under the DMCA for something because for 96% of humanity, the DMCA is a piece of meaningless toilet paper. No offence to our american friends, as I said, but as this is from the BBC, it only matters what's been done here in the UK. Until that un-democratic european nightmare inflicts more total garbage legislation onto us in the form of software patents and we get our very own version of corporate fascism. Then we'll all be stuffed.
Looks interesting though. I think a lot of people ignore or marginalise the beed, when they've come out with a hell of a lot of innovation in their time. Let's hope this is one of the 'biggies' that they're responsible for.
Firstly, the BBC is a much, much, MUCH bigger mass marketing machine in the UK than Microsoft will ever be. This codec is being paid for by every household in the UK that owns a TV set, because we're the ones who pay close to US$200/year for a license which goes directly to the BBC. The BBC are open sourcing it, but the archive project everybody is talking about will only be available to the UK audience for free, and post-Hutton might not happen at all (it was a Greg Dyke baby). So, let's see - if it does happen, the entire BBC back catalogue being made freely available in this format to the entire UK and you think this format will fail? Quite frankly, what planet are you on?
Secondly, IE "won" the browser wars because it was the best browser. It still is. The reason? Developers still code to the IE "spec", not W3C. In addition it's page loading/rendering speed and start-up is much faster than Mozilla. Simple fact, live with it. Mozilla is exactly what OSS is not supposed to be, particularly on Unix - it's 100% bloatware. Even on my 'nix boxes I have IE running under WINE because it's better.
Your last two paragraphs completely miss the point of the codec. The BBC is not releasing this for Linux users. They're creating an open format that they still control. They want us to put the time and effort into making it perfect so that everybody can share it. This has always been the way the BBC has worked from technical innovation through to it's creative stance - it gets the people who pay for it, involved in it. They do not care if the implementation makes Linux more viable - they will take any codec work and deploy it for the UK masses on windows. If they decide to release that particular build of it to you for free, be grateful.
Mark my words, within five years DIRAC will be bigger than MP3 is now.
What's the problem with distributing patented technology in source form? I believe this is legal. As an example VTK distributes the marching cube patented method (among others) with no problem.
Unisys never had a problem with any of the LZW implementation in source form. They never asked for them to be pulled out of any site, and neither could they legally. What they asked is if you were using this technology for anything other than research and study (i.e. if you really wanted to compress some file with it for redistribution) *then* you needed a license from them.
The use of patented methods for research and study is legal, this is the whole point of patenting technology. Patenting is a publication process, in exchange for exclusive control of the technology *in applications*. The idea is that other people can study this technology and improve on it.
If you as a user take some source code floating on the net implementing some patented technology, and add it to some application, be the application free or not, you are responsible for obtaining a license from the holder of the patent, but AFAIK the author of the code is in the clear, and so are the distributors.