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MP3...in Surround Sound
A number of people sent in the latest news from the fine folks at Frauhofer that they are expecting to have surround sound working for MP3s by July. The details are pretty sketchy in the article, but supposedly it won't be much more space per MP3s, and existing players will work with it.
Does your collection already have surround sound data? A bit pointless to convert, no new data to store.
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You couldn't convert your mp3's to surround because the source is stereo... if you want surround just run it through PL2 for pretty good on the spot surround sound.
I don't know why you'd need to change anything... I get surround sound right now with my ordinary stereo MP3s. It's called Dolby Pro Logic :-)
So you can have over sibilant vocals in front of you, warbly underwater bass behind you, and audio artefacts moving in circles about your head... I can't wait!
Ogg Vorbis have had support for this for some while.
What I'm not sure of is if the support for "joint" surround is there. (Like joint stereo, only for surround)
Who wants to use a proprietary sound format, when they can use a much more appealing open format.
Vorbis is also intended for lower and higher sample rates (from 8kHz telephony to 192kHz digital masters) and a range of channel representations (monaural, polyphonic, stereo, quadraphonic, 5.1, ambisonic, or up to 255 discrete channels)
h tml
http://xiph.org/ogg/vorbis/doc/vorbis-spec-intro.
MP3 is and was always proprietary...
Fraunhofer reproduces surround sound by adding to MP3 encoding extra information that describes the spatial characteristics of the main audio track.
If they are just adding information to the main track, why put that information in the file to begin with? Just let the user have a "spatial" encoder plug-in that jacks into winamp or whatever. Doing it this way increases the file size for everybody... people with and without surround systems.
Surround information should not be "created." It should be ripped and converted from the original source.
Before long we'll have the mp3 mess that we currently have with all the video codecs.
Davak
Finally Frauhofer will catch up to the innovation that Microsoft made more than a year ago. (Oh the irony) Windows Media could do this since its last realease. http://www.microsoft.com/windows/windowsmedia/9ser ies/Gettingstarted/DemoCenter/AudioQuality.asp?pag e=6&lookup=AudioQuality
Was MS first to have this technology for the mainstream consumer???
Hmm, how does your audio format get any more proprietary than before when the folks who developed it in the first place extend it?
You should wait for the iPod Micro Edition. So small it fits in your anus and uses a methane-powered fuel cell. Oh, and it comes with a 64GB solid state memory chip and supports 6.3 Dolby Surround Extreme.
An optional accessory allows the device so play through bone conduction so that you don't have unsightly earphone wires coming out of the back of your pants.
Grandparent is essentially right. MP3 *is* an outdated codec, which is only still here because of it's universality (don't get me wrong - this is a big benefit). While these added features may not actually break the old standard, they do result in bigger files with no discernable benefit for the vast majority of people. If you want to examine the success of previous add-ons to the mp3 standard, take mp3-pro - it's not exactly all over the place. People will take standard mp3 for it's universality, and choose a superior codec (AAC, OGG, MPC, whatever - even WMA) when they aren't concerned about compatibility.
Here's the deal.
By far, the most popular algorithm in use for surround sound encoding is Dolby's AC3 (I can say this, because it's on pretty much every DVD, and nothing comes close to its penetration even in the audio space -- not even DVD-Audio). AC3 itself is a pretty fascinating codec; one of the more interesting things about it is that each additional channel requires less and less bandwidth to tack on. This is because there tends to be massive correlation between channels -- either the same sound is coming from multiple directions, or a sound is coming from one direction and all the others are silent, or some combination therein. AC3 encodes this quite efficiently, and thus gets really high quality surround sound in surprisingly few bits.
I suspect they're engineering a similar mode for MP3 -- hopefully something a little nicer than Joint Stereo, which basically works by doing a mono mix and specifying which frequencies are louder in which channel. No, this doesn't work very well. Concievably, we could see something like VBR on a per-channel basis, but I suspect this would cause existing decoders to collapse. I do believe it's possible to place extra data between MP3 granules; I suppose they'll get their backwards compatible surround mode worked into there.
--Dan
Not to mention how the method of adding pretend "surround sound" that they're proposing is retarded.
For what it's worth, MP3Pro also wasn't really backwards-compatible, even though it claimed to be. In a format that didn't support the extensions, it cut off the entire high end and it sounded like absolute shit. It remains to be seen if the same issue will be seen in these surround MP3s, but if it really doesn't add too much, like the article is implying, I don't imagine it will be a cataclysmic failure.
Besides, there aren't that many surround-sound audio CDs to rip yet, so something like this wouldn't gain in popularity until a more popular codec has already superseded it. I wouldn't worry about it gaining any type of dominance.
From the article, again:
There's no extra channels, just an extra layer telling the player how to manipulate the two existing audio channels to obtain a surround-like effect. While the merits of this approach alone make me skeptical, what really bothers me about this is how different players are all going to have completely different implementations of using this extra layer of data to manipulate the audio channels, meaning we're going to have no consistency whatsoever with how it even sounds.
It would need a new connector, because you can only get stereo stereo from the iPod as far as I can tell.
For a surround output to an audio system, you would need a new connector offering at least 4 channels (Front L/R, rear L/R), line level. They'd probably make it straight-up 5.1, though.
And how do you get surround sound from a pair of headphones with only with a left and right channel?Easily. Headphones have two channels (L/R), you have two ears (L/R). Your brain does some pretty heavy duty phase analysis to figure out where a sound is coming from. In fact, binaural recording is a technique where two microphones (L/R) are mounted on a form resembling the human head, but you need to wear headphones for the full effect.
A portable device could either use 4 channel headphones (expensive, requires 4 amplifiers to drive them, would increase battery consumption) or could use a DSP integrated circuit to decode the surround sound channels, perform the phase analysis done by the human brain, and send this synthetic binaural signal to regular headphones.
But it's still a lot of work for little payoff. Most of the use for surround sound in any form is movies. Music tends to be mixed to 2 channels from the perspective of a listener sitting in front of the stage, so I think its importance in a portable device primarily used for music is pretty limited.
Fire and Meat. Yummy.
One of the places Ogg Vorbis has become surprisingly popular is in soundtracks for computer games. The no licensing fees must be one useful aspect,
No licencing fees doesn't mean just that. It also means no overhead like getting a licencing deal set up, signed, making sure it's paid on time, in right amount, used only in accordance with the terms and so on. I'm seeing this first hand how much time is spent fiddling.
Just the process of going to someone with the authoroty to sign contracts and spend money in the company's name is wasting time, and time is money. That everyone, everywhere can use it for whatever is in itself probably worth as much as the licencing costs themselves.
Kjella
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