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Xiph.org Releases Theora Alpha One
Pajama Crisis writes "Xiph.org, the crazy guys behind Ogg Vorbis, have released the first alpha version of Ogg Theora, an open video codec. Downloading, hacking and smashing into little pieces is cheerfully encouraged. Theora has been mentioned on Slashdot before. Also, Xiph has been working with a couple different companies to bring Vorbis to a portable near you; stay tuned."
The killer application is to insert a DVD and have it simplistically rip and encode it for personal viewing. Make it simplistic enough for the masses to use, and let the codec take off as a standard induced by practice not dictates or technology.
...has been rolled into Theora, as is said at both sites.
from vp3.com:
NOTE TO ALL VP3 DEVELOPERS:
Monday, September 9, 2002 -- Starting today, all source code development and maintenance for the VP3 open source codec has moved to a new home: www.theora.org. Piloted by the open-source wunderkids at xiph.org who brought you Vorbis audio, Theora heralds a new era of open and license-free multimedia.
from theora.org:
What is Theora? Theora will be a video codec that builds upon On2's VP3 codec.
So, in case anyone was wondering (like I just was), there you go.
Dear Slashdot: next time you want to mess with the site, add a rich-text editor for comments.
2) Make it impossible to uninstall.
3) Necesitate a live web connection to play files.
4) Upload information to a "security" server every time I play a music file or insert a CD.
5) Utilize DirectSound.
6) Get rid of *nix versions.
6) Release only binaries so terrorists don't get the source code.
7) Use attorneys to bring down all mirror site distributions.
8) Pick sellout a$$hole to pump out CD that installs trojan uninstallabe player onto people's system. Is Peter Gabriel available? http://www.theregister.co.uk/content/4/27272.html
9) Make sure user interface is horrbile, avoid simplicity and good design (so see QuickTime and WinAmp for what NOT to do).
10) Add interoperation with future .NET (Passport) purchasing system.
Sir (and I use the word loosely), if you're a plant for the competition, try a bit more subtlety and you'll blend in better. I've also found that borrowing buzzwords liberally from 'Star Trek' will help your gobbledygook sound more convincing to both low level nerds and the common man.
Off we go...
I've been studying psychoacoustics in my spare time,
Oh boy, a *real* expert... Give me a second to contain my excitement.
It sacrifices a lot to "sound better" than MP3, and while some of their tradeoffs do manage to improve sound quality
A terrible, terrible thing it is to sound better... there must be something wrong
First off, Vorbis concentrates its encoding in the more audible midrange
completely cutting out higher overtones. While MP3 works similarly, it manages to keep enough of the high range to maintain the "feel" of the original music.
Bzzt. False statement number one. Go study in your spare time a little harder, do some ABX testing then come back and tell us what you learned. However this one is almost forgivable compared to the nonsense below.
Vorbis claims to support more than two channel audio, but this is misleading.
Bzzt, no it's not. 255 channel support, all of which may be totally independent and un-coupled. You need not use 'joint stereo' (our method is more general and we call it 'channel coupling') at all.
MP3 encodes stereo using a "joint-stereo" method, which couples both tracks together into a mono track, giving each frame a different balance to simulate stereo on a mono track. This is equivalent to playing a mono tape and turning the balance knob!
No, idiot, that's 'intensity stereo', not 'joint stereo'. Vorbis does not use intensity stereo.
Obviously, this is less than optimal
It certainly would be, unfortunately--- *GASP* ---it's not true!
While Vorbis supports true stereo encoding, it fakes 5.1-channel audio using a "joint-joint-stereo" method, where the left-back/left-front and right-back/right-front channels and joined together into the two stereo tracks in a similar fashion. Not very good at all.
Bzzzt. Go read the spec again Bucky. You could do what's described above, yes, but that's not 'the way Vorbis does it'.
The way that Vorbis compresses its audio accelerates speaker degradation
Actually using the speakers accellerates degredation too. They last alot longer when you leave them in the box they came in and don't plug them in.
It breaks sound up into an evenly-spaced array of harmonics which approximate the original waveform
Those are not 'harmonics', and Vorbis's compression pays no particualr attention to sinusoidal harmonics. Perhaps you'd like to wait until college and get some signal processing lectures under your belt before coming back.
"Big deal", you say, "that's how all lossy encoding schemes work!"
[sigh] No, no it's not.
But if we assume, for a second, that you said, 'Vorbis is a transform-domain codec', which is what you meant, no, not all lossy audio compression formats are transform based.
But the way that Vorbis does it causes a noticeable amount of harmonic resonance in speaker systems, stressing their driver system and accelerating the rate at which they decay.
The problem Sir is that you have a surplus of Zackthorp particles coming from your warp core, a well known source of wear and tear on cheap speakers. Make sure your speakers are rated for greater than warp 4 before trying to use them so close to a Gammagorp Modulator and your worries are over!
I listened to the result, and believe me, it's true! Because I said so.
If you know the story of the first Tacoma Narrows bridge [carleton.ca], this is the same principle, working at a smaller and more gradual pace.
Given Xiph's poor track record with Vorbis
OK, let's stop here. Everyone gather around, point and laugh!
Monty
[sheesh]