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But all that's missing the point. The point is that it's *OPEN* and not under the control of any nasty for-profit corporation. And that makes it superior. Who *cares* if it doesn't work worth a damn in actual practice?

That. MP3 became the de facto standard despite the existence of far better quality formats for the exact same reason. We currently have to choose between two kludges, badly implemented possibilities, one of them being open. The choice is easy to make.

I'm pretty sure the MP3 compression algorithm is not open. These folks make a nice bundle of money from it. A little more background information is available here. Rates and fees are covered here.
I don't know if The Fraunhofer Society is "for profit", but it would seem they co-own the rights to MP3 and via Thomson Consumer Electronics, they do collect money for it's use.

I was playing around with the VQF format at that time. Sounds great compared to MP3 at the same bit rate. At least Vorbis had *some* hardware support.

http://www.mp3-tech.org/vqf.html

This test isn't a complete experimental fiasco (like some of the Microsoft-sponsored listening tests that deem WMA to sound as good at 64k as MP3 at 128k).

But there are a couple of significant flaws with it, that make the results pretty useless:

• They used the AB method, rather than the superior ABX method. In the AB method, a participant hears the two versions of the song, without knowing which is which, and then much choose whether one is better, or whether they are equal. In the ABX method, the participant hears two distinct versions, then a third which is identical to ONE OF the first two. They are asked to figure out which of the first two samples is the same as the third. If they perform no better than chance at this task, it's a good indication that the null hypothesis may be correct. Which is very important, since modern audio codecs have gotten so good that their quality is often indistinguishable in practice. It's disingenuous to argue about slight degrees of preference without an attempt to determine their statistical significance.
• We don't know exactly which codecs were used!!! There are many implementations of AAC+ encoders, which may differ markedly in quality (though in 2006, a credible ABX test found that none was preferred over another to a statistically significant to a 95% confidence interval). Likewise, there are multiple implementations of Ogg Vorbis encoders. The aoTuV patches, in particular, are widely considered to considerably improve sound quality.

If you want to know about some methodologically-better comparisons of audio codec quality, please see the Codec listening test page at Wikipedia. Full disclosure: I wrote most of this article, and have attempted to compile the results of all the carefully-conducted independent tests that I could find.

Finally, none of this is to say that we should all demand 160kbps streaming audio if 48kbps can be made to sound just as good. It's just that this study doesn't establish that, not by a long shot. The headline is also wrong in claiming that 1/3 of the participants couldn't distinguish 48k from 160k audio: in fact, they preferred the 48k audio. And preferring one format is very different from claiming that it is of a high-fidelity: for example, audio with a compressed dynamic range is by definition degraded, and yet it persists in commercial rock recordings because uniformly loud music grabs listeners' attention more easily.

AAC as used by Apple is part of the MPEG-4 standard. Apple didn't invent it and doesn't own it.

All digital music, with the exception of purely synthesized stuff, has to pass through an analog-to-digital conversion process that throws away information (quantizing). So "uncompressed music" is still actually compressed -- and lossy-compressed at that -- if it's in digital form. The question has never been compressed vs. uncompressed, but rather what type and level of information loss you find acceptable.

I'm happy with a compression format that is not encumbered with lots of onerous license terms (i.e., that I could write and distribute an open-source player for if I felt like it) and that produces quality slightly better than the point at which I can hear the difference on a good stereo system. The "slightly better" simply so that if I get an even better stereo system later on, I still won't hear the difference. As long as that baseline is met, I want the format to take as few bytes per song as possible.

Does that make me not "people?"

While it's often said that AAC is not a proprietary format, this is untrue. Like other proprietary formats AAC requires agreeing to the patent license which among other things requires licensees to distribute their AAC content in a proprietary container.

As the parent poster mentions, patent royalties are not required to distribute content, but patent royalties are required to encode/decode content so the format is as proprietary as any other.

1. Right. I forgot they were selling to aging baby boomers. And it appears that low bitrate mp3 files do discard spectral information above 16-18 kHz Since Apple sells low bitrate stuff, it stands to reason. At the same time, though, they have a lossless codec, and their airport does have a spdif connector

2. ah well, when the stereo speakers are positioned that closely together, I suppose it doesn't quite matter if stereo imaging of bass is theoretically possible. My stereo's recommends a crossover of 150 hz for 90 mm drivers. But if the wavelength (2.3 metres) is long enough...

3. Apple itself wants this to replace older systems.

"Introducing the stereo for the new century."
"Wide frequency range: iPod Hi-Fi accurately reproduces the lowest cello notes and the highest piccolo notes; the brittle strum of an acoustic guitar and the powerful thump of a driving bass"

Let's see:

Lowest Cello note: C2 65.41 Hz
Highest Piccolo note: that's not terribly impressive

I suppose Apple took one look at Bose, and decided that selling overpriced audio gadgets was more lucrative than coming out with properly designed stuff...

If that were true, it is strange that strings like "0.90", "LAME3.95", "3.95", "3.95 " -- indicating a specific version -- are in there.

I mean, why would they look for a *specific* version of LAME if they want to rule out mp3 encoding software running on the machine?

Also check this post: http://slashdot.org/comments.pl?sid=167537&cid=139 69409

"Go and check it yourself, and compare to lame sources. The data from tables.c is included in the executable in identical form (several large tables), also all the version strings are included, which the DRM system doesn't check.

The data is there, the big question is if it was linked accidently, or if it actually uses LAME code as well."

He's talking about the *data* of several large tables being in there.

Further more, the theory that the DRM software would be using these strings in order to look for "incompatible" programs does not look very plausable, because the DRM kit seems to look for program names rather than scanning the executables, judging from the strings posted here:

http://hack.fi/~muzzy/sony-drm-magic-list.txt

Besides, that does not explains the date from the tables being in there.

Further, we have a post by a F4I employee on usenet talking about an mp3 player he wrote:

http://groups.google.com/group/microsoft.public.wi ndowsmedia.drm/browse_frm/thread/8270cbc85f8e9cb8/ 7cb5c4ad49fa206e?lnk=st&q=FIRST4INTERNET&rnum=44&h l=en#7cb5c4ad49fa206e"

"I am currently writing an MP3 player with lots of bells and whistles including a wave editor, fades, reverbs etc.
What I now need is to be able to protect the files it creates. I have already written the routine to convert the MP3 into a WMA file.
Does someone have some simple C++ code which can write Microsofts DRM v1 properties that the user whishes to set(i.e. 3plays 4 copies etc) over the unprotected file to make it protected. There may be some cash on offer here if its easy to use! All I need is a procedure that performs this"

And, another thing is that LAME also seems to be cabable of decoding: http://mp3decoders.mp3-tech.org/decoders_lame.html

Taking things togeter, to me it looks unlikely that they are looking for a specific version of LAME by scanning trough executables, while for other mp3 playing software they simply look for the name of the executable.

I think it is very well possible they use of have used LAME in their mp3 player. Then the strings and tables either indicate that Lame is indeed being used by the bundled player to play mp3s, or they mistakenly linked the Lame library because they did use it in other parts of their software and somehow did not realise they were linking the Lame lib.

This explains why Microsoft would need to pay royalties. Even LAME is not exempt (at least in Germany & the USA) - the whole reason for its original name ("LAME Ain't an Mp3 Encoder") is to help avoid the patent issues around mp3 encoding.

Yes there is - MP4 (AAC) is higher quality than MP3 at the same bitrate.

Plus if its not backwards compatible it wont be adopted.

Jump to a a random offset, look for the sync-word, copy a number of frames, repeat. The MP3 format is made of frames, there is no per-file header and since the format is designed to be used in streaming applications and to be robust against errors, you can jump right to the middle and grab a couple of frames without worrying about the rest. Many webpages have the frame spec. Here is one.

Indeed. I believe Microsoft made a pretty big mistake with the WMP 7 interface, so my first thought when I saw a screenshot of this thing was 'what an ugly piece of shit'. Seriously, having something that bloated, rivalling RealOne, could at last push me to try and find other players for my media.

Take a look at a comparison between what a lovely, no-nonsense interface WMP used to have, and what it is going to have pretty soon. Whilst I've never been a fan of the million-and-one ugly visualizations anyway, this is a great example of bloatware, with far, far too much being crammed into one piece of software, which should have a limited, defined functionality.

Why can't the default media player's interface be kept simple, as it used to be? Why does it have to take up the whole screen to be useable nowadays?

And does anyone know where I can find a decent media player for windows that supports all the formats of WMP10, but has the elegance of WMP6 (yes, I know about the 'classic' skin in WMP9 but will that be around forever?)? Mplayer, right? :-)

Why would one want OGGs anyway?

• I haven't paid for an MP3 encoder, and I'm not going to play that game. (Yes, Thompson/Fraunhofer could theoretically pull a patent out of their portfolio that affects Vorbis, but they haven't yet)
• Foobar2000 and Opie-Player 2 are the players I use.

Nitrane is trash. Fortunately for Winamp users, it hasn't been in use at Nullsoft for years.

Read these, particularly the second link:

http://mp3decoders.mp3-tech.org/decoders_winamp.ht ml
http://mp3decoders.mp3-tech.org/decoders_winamp2_6 2.html

And BTW, Fraunhofer's decoder ran on 486s. It just wasn't real-time on most such systems. :)

Nitrane is trash. Fortunately for Winamp users, it hasn't been in use at Nullsoft for years.

Read these, particularly the second link:

http://mp3decoders.mp3-tech.org/decoders_winamp.ht ml
http://mp3decoders.mp3-tech.org/decoders_winamp2_6 2.html

And BTW, Fraunhofer's decoder ran on 486s. It just wasn't real-time on most such systems. :)

As an avid WNYC listener and member, I applaud the choice to move away from Windows Media format. However, MP3 is a patented format that is not Free (as in Freedom). I am sure that I am in the minority here, but I can't help but feel that in some way I am being slighted. In my opinion, the principles involved in my choice to use Free Software on my computer are much akin to the reasons I choose to listen to Public Radio.

mp3licensing.com states:

"A license is needed for commercial (i.e., revenue-generating) use of mp3/mp3PRO in broadcast systems (terrestrial, satellite, cable and/or other distribution channels), streaming applications (via Internet, intranets and/or other networks), other content distribution systems (pay-audio or audio-on-demand applications and the like) or for use of mp3/mp3PRO on physical media (compact discs, digital versatile discs, semiconductor chips, hard drives, memory cards and the like)."

"However, no license is needed for private, non-commercial activities (e.g., home-entertainment, receiving broadcasts and creating a personal music library), not generating revenue or other consideration of any kind or for entities with an annual gross revenue less than US$ 100 000.00."

How does this apply to WNYC? I for one prefer not to have my contributions to be used to pay support this kind of thing, when it is against my social and political ideals. Especially when there are free (as in beer and speech) alternatives such as the Xiph project.

It is my hope to not second guess the current decision to standardize on MP3, but to perhaps begin a dialogue for openness in media formats in the future of public radio. For now I can live with MP3. I will have to compromise and add non-free software to my computer, for now.

Yeah...because the number of people who have an iPod and run Linux, is a lot greater than the number of people who run XP and use WMA regularly.

Yes, a lot of people do use, and like WMA files. Please don't tell us that the supposed low quality of WMA.

BTW What's going on here? Decoder tests show that later versions of Winamp are among the best. Why do mad and QuickTime seem better.

It would be three more years till Napster came around. I remember telling everyone (family, friends) about how this new MP3 thing would revolutionize music. I was mainly thinking streaming music, since at only 56k, the thought of downloading full albums (even compressed to 50-60MB) seemed a little far off. At that time the best there was for streaming was RealAudio, which sounded like crap (and still does IMO).

But even a few years before that... (~1994)

Ok, technically I didn't download it, and it wasn't an MP3. My Pro Audio Spectrum 16 (PAS16) came with a demo 44.1khz 16bit wav clip of the song "I need you tonight" by INXS. What I do remember is that is the first time I heard "CD quality" sound come out of my computer. Later on I tried compressing it with l3dec and noticed it performed at aroun 5x real time ;-).

No. MP3 encoders have to decide what to get rid of and what to keep based on your desired bitrate and settings. They use a psycho acoustic, frequency cutoff, and can join channels based on frequency range[1]. Each mp3 compressor has a different model it follows to achive the smaller file, some are percieved better then others.

[1]
Lower frequencies are harder for a person to determine the location of the source. This is the basis for home theaters with one subwoofer running in mono placed anywhere nearby. You do not really need a left and right subwoofer and placement is not as important from an imaging perspective (although placement can efffect the speakers frequency response). You can save space in compression of lower frequencies by combining certain lower frequencies from both channels into one center channel. The low frequency analysis is just a small portion of of the audio spectrum and for good compression, the ranges are treated differently for different reasons.

Not so soon. Patents last 20 years from the filing date.
Seems like this patent is valid for another 14 years.
See MP3 patent.

Because the author of LAME has'nt licensed the right to use the Fraunhofer MP3 Patent. If the commercial software companies license the patent, they're allowed to use any encoder they want in their products, including LAME. OGG Vorbis is'nt covered by this patent. Details about MP3 patent licensing are availalble here.

That's a pretty crappy test criteria-- limiting the input to 128kbit/sec-- for those of us itnerested in achieving as-close-to-CD-as-possible performance from our compressed music.

I don't claim to have golden ears, but I can distinctly hear the difference between different playback engines (example; on a Mac, the Audion playback engine is considerable better sounding than iTunes) and different encoding engines with nearly the same settings (LAME is, by far and away, the best I have heard yet).

In any case, it would be useful to have an expanded test that includes higher bitrates for those that listen to tunes on something other than crappy computer speakers.

Ogg vs. LAME article

An excellent Ars article that only covers differences between mp3 encoders.

MP3 tech has a bunch of useful resources.

One of the best sites around, r3mix offers a wealth of technical information, some very well executed scientific and listening tests, and a section that destroys a lot of the myths surrounding mp3s.

I believe it's marketed as TwinVQ and is indeed part of the standard: http://www.iis.fhg.de/amm/techinf/mpeg4/scalable.h tml
http://www.mp3-tech.org/programmer/decoding.html

--

Does anyone have a utility to change these bits on MP3s?

MPEG-Layer 3 Bitstream Syntax and Decoding. (It's a zipped MS Word document, so break out unzip and catdoc.

If that's too heavy, here's a simpler explanation: the MP3 header is 32 bits (bit 0 through bit 31). Bit 28 is the copyright bit, and bit 29 is the original bit. You can view them with mp3info -f '%O %o' foo.mp3. You can change them with a hex editor (set the second nybble of the fourth byte to 4, assuming the emphasis bits are 00).

If you needed to read this message to learn how to do this, I strongly suggest making a backup of the file before you edit it.

Although they ask for payment for decoders, they do not have legal grounds for asking for it (their patents are only on the encoding process). For more information, refer to this (slightly dated) document at mp3-tech.org.

Although they ask for payment for decoders, they do not have legal grounds for asking for it (their patents are only on the encoding process). For more information, refer to this (slightly dated) document at mp3-tech.org.

Try www.mp3-tech.org or www.mpeg.org for more technical information.

Does this book actually cover algorithms and techniques for encoding MP3s? I know there are algorithms and information on the net, but its one of those areas where how the algorithm is implemented makes all the difference - you really can hear the difference between say BladeEnc and the Fraunhoffer codec.

From the sounds of it, it doesn't which is a pity really as the rest of it is the sort of thing which will become out of date very quickly - the legal situtation is coming to a head and the technology is rapidly advancing. As such, I doubt this will be a huge success with those already familiar with MP3s.