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Dirac 1.0.0 Released
dylan_- writes "According to their website, 'Dirac is an advanced royalty-free video compression format designed for a wide range of uses, from delivering low-resolution web content to broadcasting HD and beyond, to near-lossless studio editing.' Now a stable version of the dirac-research codebase, Dirac 1.0.0, has been released. The BBC have already successfully used the new codec during the Beijing Olympics and are looking to push it to more general use throughout the organisation. The latest version of VLC (the recently released 0.9.2) has support for Dirac using the Schroedinger library."
I see the first 4 bytes are 0xBBCD.
British Broadcasting Corporation Dirac.
From the FAQ:
What are the license conditions?
The Schrodinger software is available under any of the GPLv2, MIT or MPL licences. Libraries may also be used under LGPL.
Sounds like someone wanted there to be no question about whether it was open source.
I was wondering where I could find some vids to check out quality vs. file sizes and found this index of demo files. Looks great in VLC, quite impressive even at lower bitrates.
I hope I didn't brain my damage.
Theora gets a bad rap for being outdated technology, but it does have a few advantages over MPEG-4 ASP: the loop filter, adaptive block sizes, and multiple reference frames, putting it closer to H.264 than MPEG-4 ASP. With these features, it's really a pretty strong showing from Xiph, and things can only get better as the encoder nears 1.0.
All the R&D papers I have read and from folk in the field working on this. Its well recognized that psychoacoustic models are far more developed than psycho visual models.
I don't doubt that some people can tell the difference between flac and mp3/ogg/aac. But the true number is far less than the claimed number (do a proper blind test to really find out). Also you don't design codecs for 0.5% of the population that can hear the difference, but for the 90% that can't and the other 9.5% that don't care.
Now its a fact that PSNR is used in most encoders. Its also widely recognized that it is not a good measure. I have done my own image compression and got better PSNR than jpeg per bit, and yet it looked far worse.
So I'm not really sure where you getting the idea that is even in the same category as audio.
If information wants to be free, why does my internet connection cost so much?
Since you claim this I assume that you tried the 1.0.0 already - I watched the promo vid, and it says the BBC is using the codec to handle HD content over their standard def infrastructure at very low latency (a few ms, if I remember correctly).
Nonetheless, this seems to be an interesting thing to keep an eye on, because the codec specs address good compression especially for very high bandwidths, which is going to be an important issue for movie post production/processing, HD content and the likes. The promo vid is well worth watching.
I hope I didn't brain my damage.