Windows Media Audio: Difference between revisions

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WMA is Microsoft's compressed audio format. It's actually a generic name for several codecs that can be used inside it:
'''Windows Media Audio''' ('''WMA''') are Microsoft's compressed audio formats; "WMA" is a generic name for several [[codec|codecs]].  .wma ''files'' (and .wmv files) are [[ASF]] container files with a suffix indicating content, much like would later be done by renaming audio-only mp4 files into ".m4a".


=Windows Media Audio=
Use of these codecs largely depend on Windows components, and support has waned over the years to the point where they might be considered abandonware: by 2011, Microsoft's own music store abandoned WMA lossy completely in favour of MP3<ref>https://support.microsoft.com/en-us/topic/support-for-rights-managed-purchases-in-zune-69161d07-acae-1fdf-f98f-e0916758e49b</ref>, and certain Windows versions have been shipped with broken WMA Lossless decoding.<ref>https://hydrogenaud.io/index.php?topic=121732</ref><ref>https://forum.dbpoweramp.com/showthread.php?39459-WMA-Lossless-Encoder-is-BROKEN</ref>. As of 2024, there is only one major music store offering WMA downloads<ref>https://en.wikipedia.org/wiki/Comparison_of_digital_music_stores</ref> (Qobuz, offering both lossy and lossless WMA<ref>https://help.qobuz.com/en/articles/10167-what-are-the-different-audio-formats-available-for-download</ref>).


Also known as WMA Standard or WMA Std, it was created by Microsoft to compete against [[MP3]], that was quickly becoming the de-facto standard format for lossy compression.
Hardware WMA-enabled players are still around &ndash; including in-car units; anectodally, several hardware "WMA" players fail to support WMA Lossless, and support for the "Pro" variant is unknown.  FFmpeg offers decoding of all the format variants described on this page, and so ffmpeg-based players should be able to handle them.  


Even though Microsoft claims it is able to deliver the same quality as MP3 at half the bitrates, that statement is certainly false. A more realistic number would be same quality at around 25% smaller bitrates - and that applies to low bitrates only. At 128kbps, it is easily bested by [[LAME]].
== Windows Media Audio (Standard)  ==
The original WMA codec, later referred to as WMA Standard or WMA Std, was created by Microsoft to compete against [[MP3]], the market leading format for lossy compression.  It was released in 1999, and an upgrade later the same year; those are sometimes referred to as WMA 1 and WMA 2.


WMA Standard is the second most widespread lossy format (only losing to the ubiquitous MP3), mostly thanks to Microsoft's aggressive marketing tactics.
Upon release, WMA was aggressively pushed by Microsoft with promises of MP3 quality at half the bitrate, a claim debunked by independent listening tests<ref>https://en.wikipedia.org/wiki/Codec_listening_test#Results</ref>.  WMA did become widespread; at one point in time it was the second-most widespread lossy format for end-users.


== Windows Media Audio Professional ==
Windows Media Audio Professional (WMA Pro) was an early 2000s further development to address limitations in WMA Standard. It supports [[multichannel]] encoding and high resolutions (24bit, high [[sampling rate]]s).  Improving over WMA standard, WMA Pro scored as statistically tied with top encoders in independent listening tests at the time (without lending credibility to Microsoft's claim of MP3 quality at half bitrate).  Supporting multichannel, it was at some time seen as a potential competition to [[DTS]].


==Windows Media Audio Professional==
Like WMA Standard, WMA Pro also came in revised versions: WMA Pro 10 offers an additional layer atop the original WMA Pro 9, information that will be lost on a "WMA 9" player.


Windows Media Audio Professional (WMA Pro) was recently released to address limitations in WMA Standard. It supports [[multichannel]] encoding and high resolutions (24bit, high [[sampling rate]]s)
== Windows Media Audio Lossless ==
This is the mathematically [[lossless]] codec in the Windows Media family, first released in 2003 (and like WMA Standard and WMA Pro, the format has later been extended). Compression efficiency-wise, it doesn't come close to the default settings of [[FLAC]], [[WavPack]], [[Monkey's Audio]] and [[ALAC]], see [[Lossless comparison]] for more details. [https://hydrogenaud.io/index.php?topic=117275.0 Several releases of Windows 10 had faulty decoders built-in] and, lacking a specification, few independent implementations exist and [https://hydrogenaud.io/index.php?topic=121732 decoding is not always lossless].


Since it's backwards incompatible with WMA Std, Microsoft took the opportunity to make a high quality encoder out of it. Meanwhile WMA Std lost even to MP3 in an informal public listening test, WMA Pro was ranked at the top (next to other high quality formats) in a similar test.
== Windows Media Audio Voice ==
This codec, introduced with Windows Media 9, was used in the Microsoft telephones. It was considered to deliver very acceptable voice quality at bitrates around 4 and 20 kbps. It would allow switching over to the WMA Standard algorithm for signals with both voice and music, and Microsoft's encoder could detect music and switch over automatically.


These days, Microsoft is pushing the Pro codec for inclusion in the next generation DVD standard as standard audio format.
== Additional Reading ==
<references/>
* [https://learn.microsoft.com/en-us/windows/win32/medfound/windows-media-codecs Description of Windows Media codecs] (including Windows Media Video codecs) at Microsoft
* [[Lossless_comparison|HA Wiki's Lossless Codec Comparison]]




==Windows Media Audio Lossless==
{{navbox audio codecs}}


This is the matematically [[lossless]] codec in the Windows Media family. It's a welcome addition since it was the first lossless codec backed up by a major player in the multimedia compression field. Compression efficiency-wise, it's on par with [[WavPack]] high and between [[Monkey's Audio]] fast and normal.
[[Category:Codecs]]
 
==Windows Media Audio Voice==
 
This codec, among the first ones to be added to the Windows Media portfolio, is VoiceAge's [[ACELP]].net. It delivers very acceptable voice quality at bitrates around 4 and 20kbps.
 
 
==Addional Reading==
 
* [http://www.microsoft.com/windows/windowsmedia/9series/codecs/audio.aspx Description of Windows Media Audio codecs] at Microsoft
* [[Lossless_comparison|Lossless Codec Comparison]] by Rjamorim

Latest revision as of 21:03, 9 February 2024

Windows Media Audio (WMA) are Microsoft's compressed audio formats; "WMA" is a generic name for several codecs. .wma files (and .wmv files) are ASF container files with a suffix indicating content, much like would later be done by renaming audio-only mp4 files into ".m4a".

Use of these codecs largely depend on Windows components, and support has waned over the years to the point where they might be considered abandonware: by 2011, Microsoft's own music store abandoned WMA lossy completely in favour of MP3[1], and certain Windows versions have been shipped with broken WMA Lossless decoding.[2][3]. As of 2024, there is only one major music store offering WMA downloads[4] (Qobuz, offering both lossy and lossless WMA[5]).

Hardware WMA-enabled players are still around – including in-car units; anectodally, several hardware "WMA" players fail to support WMA Lossless, and support for the "Pro" variant is unknown. FFmpeg offers decoding of all the format variants described on this page, and so ffmpeg-based players should be able to handle them.

Windows Media Audio (Standard)

The original WMA codec, later referred to as WMA Standard or WMA Std, was created by Microsoft to compete against MP3, the market leading format for lossy compression. It was released in 1999, and an upgrade later the same year; those are sometimes referred to as WMA 1 and WMA 2.

Upon release, WMA was aggressively pushed by Microsoft with promises of MP3 quality at half the bitrate, a claim debunked by independent listening tests[6]. WMA did become widespread; at one point in time it was the second-most widespread lossy format for end-users.

Windows Media Audio Professional

Windows Media Audio Professional (WMA Pro) was an early 2000s further development to address limitations in WMA Standard. It supports multichannel encoding and high resolutions (24bit, high sampling rates). Improving over WMA standard, WMA Pro scored as statistically tied with top encoders in independent listening tests at the time (without lending credibility to Microsoft's claim of MP3 quality at half bitrate). Supporting multichannel, it was at some time seen as a potential competition to DTS.

Like WMA Standard, WMA Pro also came in revised versions: WMA Pro 10 offers an additional layer atop the original WMA Pro 9, information that will be lost on a "WMA 9" player.

Windows Media Audio Lossless

This is the mathematically lossless codec in the Windows Media family, first released in 2003 (and like WMA Standard and WMA Pro, the format has later been extended). Compression efficiency-wise, it doesn't come close to the default settings of FLAC, WavPack, Monkey's Audio and ALAC, see Lossless comparison for more details. Several releases of Windows 10 had faulty decoders built-in and, lacking a specification, few independent implementations exist and decoding is not always lossless.

Windows Media Audio Voice

This codec, introduced with Windows Media 9, was used in the Microsoft telephones. It was considered to deliver very acceptable voice quality at bitrates around 4 and 20 kbps. It would allow switching over to the WMA Standard algorithm for signals with both voice and music, and Microsoft's encoder could detect music and switch over automatically.

Additional Reading

  1. ↑ https://support.microsoft.com/en-us/topic/support-for-rights-managed-purchases-in-zune-69161d07-acae-1fdf-f98f-e0916758e49b
  2. ↑ https://hydrogenaud.io/index.php?topic=121732
  3. ↑ https://forum.dbpoweramp.com/showthread.php?39459-WMA-Lossless-Encoder-is-BROKEN
  4. ↑ https://en.wikipedia.org/wiki/Comparison_of_digital_music_stores
  5. ↑ https://help.qobuz.com/en/articles/10167-what-are-the-different-audio-formats-available-for-download
  6. ↑ https://en.wikipedia.org/wiki/Codec_listening_test#Results


Audio codecs: type/usage for end-users to encode on physical media etc. legacy formats
Lossless (Uncompr. LPCM) • ALAC • FLAC • Monkey's Audio • MPEG-4 ALS • OptimFROG • TAK • TTA • WavPack MLP/Dolby TrueHD La • LPAC/LTAC • RealAudio Lossless • RK Audio • Shorten • WMA Lossless • (others)
Lossy (ADPCM formats) • AAC • AC-3 • MP2 • MP3 • Musepack • Opus • Vorbis AC-3 • DTS • (Bluetooth codecs) ATRAC • QDesign • Real Audio • RK Audio (lossy modes) • Speex • VQF • WMA
Hybrid lossless&lossy OptimFROG DualStream • WavPack DTS-HD MA • MPEG-4 SLS ATRAC Advanced Lossless • mp3HD
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