Talk:Comparison of audio codecs

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[edit] Suggestions

This article needs expanding and updating. Ace ofgabriel (talk) 18:30, 22 March 2008 (UTC) The licenses section should be limited to three or so of the more popular tools (e.g.: envolve encoding, for the most part).

Latest stable version could use some work. Perhaps split into reference tool version, and spec. version?

Perhaps narrow down the *nix OSs to just "*nix". I am aware that there is an open source decoder in the works for ALAC, however I think it's not released yet.

mplayer 1.0pre7 and above has native support for decoding ALAC.

The stereo column could use some detail as to what mid/side, intensity, etc mean. Also do we need a mono column? I do not think bits per sample applies to lossy codecs (for the most part store data in frequency domain, and most are able to output into floating point). Perhaps some explaination is due as well: bits per sample here means of the original waveform, not of the stored compressed version (see Wavpack's rate description). For the values in parenthesis I mean that the format specification supports the values, but the software available doesn't fully support it.

Some links to debates about which format is best would improve the article greatly. Cacophony 21:26, 29 December 2005 (UTC)


What is 'Hybrid' in algorithm in technical details table? would've been better if there was more info on that.. 61.17.227.44 11:30, 9 March 2007 (UTC)

[edit] Probably a mistake on the sample rates

I'm not sure, but are all the sample rates correct? WMA, for example, has 48000kHz. Isn't it 48kHz? Some other values are strange too. --200.165.128.150 14:42, 28 February 2006 (UTC)

[edit] Cleanup needed

This article needs work. What is its encyclopedic context? Is it a sub-page of audio codec? If so, it should have a {{main}} tag.

What is the significance of the audio codecs selected? Do they each form a large, well-documented share of audio files? If not, why were countless other codecs excluded from this list? Why is WMA stated to be unsupported on Mac OS X, when a Windows Media Player has been available on the platform and Flip4Mac provides current support?

Why is the latest stable version mentioned? How are the stable version numbers being verified? Whose implementation is considered to be "the real codec" and why? —donhalcon╤ 20:10, 7 March 2006 (UTC)

None of the Category:Software comparison articles are really sub-pages. They have been treated as encyclopedic as stand-alone entities. However, this aricle might benefit from the expansion of the short introductory paragraph (sofixit).
Note there is a request for expansion, so I won't comment on included/excluded codecs.
I do agree that WMA should probably state "supported" on OS X.
The latest stable version provides a check on how current the comparison is. These numbers may easily be verified by any number of methods (not the least of which is to check back with the documentation for the codec, itself. The version numbers and features appear to be for the reference implementation, but the OS support seems to be ANY implementation. Perhaps this table can be expanded to say whether there is a reference implementation or whether the only implementations are by someone other than the original author (particularly on the *nixes). --Karnesky 20:08, 7 March 2006 (UTC)

This Article needs expansion and updating. Ace ofgabriel (talk) 18:29, 22 March 2008 (UTC)

[edit] Reliable sources

What do people here consider as reliable sources? My company has developed an audio codec which is mentioned in an article I am working on here, and would like to know where editors working on this comparison expect information to be published. Stephen B Streater 20:31, 9 June 2006 (UTC)

[edit] More codecs that should be added.

Of course, there's more at hydrogenaudio, but there's a couple more.

[edit] Some issues

  1. For the purposes of this article, what is the difference between "BSD" and "Unix" (from the "Operating system support" section)?
  2. The statement "this enables their use on any POSIX-complaint system" (from the same section, footnotes) is misleading. Typically, a string of other libraries is required (which are not part of POSIX), and some type of output system (ALSA, OSS, ...; also not part of POSIX).
  3. The use of "OSI" to refer to the open-source implementations is a bit confusing. Simply because the OSI approved the licenses under which the software was published does not mean that they endorse that piece of software, nor that that piece of software has any other affiliation with OSI. Perhaps "OSS" (open source software) or just "Open-source" would be more appropriate.
  4. Perhaps there should be some mention of whether samples are floating-point or integer in the heading "bits per sample" in the "Technical details" section.
  5. How exactly does WavPack do "2.2" bits per sample in lossy mode? Does every fifth sample get an extra bit?
  6. Is a "Monaural" column really necessary? Can it not be assumed that all audio formats support one channel of audio?

—Kbolino 10:03, 17 July 2006 (UTC)

[edit] Implication of inferiority of patented formats

By using red for patented formats and green for free formats, we are clearly implying their inferiority, which in my neck of the woods is called POV. Recommend neutral coloring for that section. - 211.28.81.162 03:24, 20 November 2006 (UTC)

Agreed. Since this issue has been around for a while & there have been no arguments FOR the use of the "but no" and "but yes" templates, I'm going to remove them. --Karnesky 01:46, 13 March 2007 (UTC)
But it's still non-neutral POV! The patented ones are now green and the free ones are red, again, implying inferiority of the free ones. This is no good either, this is not the same as a feature checklist where it makes sense to imply missing features are somehow inferior. Not being encumbered by patents is not a missing feature. The neutral thing to do in this case is to just use the words "yes" or "no" without the colorizing templates; or even better perhaps the descriptive more neutral words "patented" and "unencumbered". Use of colors in this column adds no value at all and just implies favoritism one way or the other. - Dmeranda 21:46, 5 April 2007 (UTC)
"green" means "yes" and "red" means "no." Neither means good/bad/inferior/superior/etc. --Karnesky 22:00, 5 April 2007 (UTC)
For more than one person, they have meant good/bad/inferior/superior/etc, personally it was that way, even before reading what it says in the box, it seems that what is unencumbered is "evil". Colors should be removed. --Nando.sm 06:51, 12 April 2007 (UTC)
Further in technical details, it still seems "bad" that not having a constant bit rate. What could be done, and if you like (i know this is for everyone, and not for only a small group of people, but if they agree) to have checks and crosses for has and has not. Don't know if it could work, but options have to be given. --Nando.sm
On the template talk pages, there was general consensus that green meant yes, rather than "good." It seems inappropriate to disregard this recent opinion which was advertised on all pages which used the templates for one particular page with far fewer readers. There was also a poll on checks, etc. If you think the templates should be improved, clearly the place to discuss it is on the template talk page. That the templates are called and have the self-proclaimed mission of substituting for "yes" and "no" suggests they can be appropriate in those columns. --Karnesky 16:07, 12 April 2007 (UTC)
It seemed evil before, but now it looks ugly... i will be killed for this, but wikipedia has reached concensus, so I will accept it. For information about color tags in tables go to table cell templates. Now in other things why not use the yes2 and no2 they are not so color saturated so it could have less appeal to the human eyes. Nando.sm 17:35, 30 May 2007 (UTC)

[edit] What constitutes "one codec"?

Some of the format compared in this article really comprise multiple separate codecs, in that no decoder program could decode all variants of them. For example, "AAC" lumps together several variants: LC-AAC (the standard version), HE-AAC (an enhanced version), HE-AAC v2 (a revision of HE-AAC), etc. A decoder that only understands the baseline LC-AAC won't be able to play back HE-AAC. By comparison, any reference-compliant MP3 decoder should be able to decode any MP3 file... whether it's encoded with some ancient Fraunhofer encoder, or the latest version of LAME.

In addition to AAC consisting of multiple incompatible codecs, ATRAC also has incompatible variants, and RealAudio uses numerous variant codecs (it's more of a container format than a codec). WMA may refer to multiple incompatible codecs as well (WMA 1/2, WMA Pro, WMA lossless, WMA voice). It seems that these "codecs" should be more properly described as brand names of loosely related codecs.

Anyone have any suggestions as to how to convey this confusing state of affairs in the article? MOXFYRE (contrib) 17:53, 5 October 2007 (UTC)

[edit] Comparing codecs or formats

I find it very unclear if we're comparing codecs or formats here. The title says “Comparison of audio codecs” while the table apparently compares formats — i.e. AAC to MP3 instead of LAME MP3 codec against Nero MP3 and QuickTime AAC. The table even has an “implementation” entry. Shouldn't the comparison be between those? —Preceding unsigned comment added by 81.243.206.5 (talk) 10:43, 4 March 2008 (UTC)

I agree that this article is not correct. Audio formats are not audio codecs. RealAudio is not a codec, it's multiple codecs that constitute a format. Some of the information here needs to be moved and/or deleted. Sapwood2 18:32, 13 April 2008 (UTC)