Lossless Codecs - Which is the best lossless codec?
原文出处：http://www.hydrogenaudio.org/forums/index.php?act=ST&f=19&t=29655
Hydrogenaudio Forums - Lossless Codecs - Which is the best lossless codec?
Posted by: rjamorim Nov 25 2004, 10:14 PM
Given the enormous amount of lossless audio compressor choices available,
it is a very difficult task to choose the one most suited for each person's
needs.
Several people only take into consideration compression performance when
choosing a codec. But as the following table and post shows, there are
several other features worth taking into consideration when making that
choice.
For example, users wanting good multiplatform compatibility and robustness
(E.G, people sharing live recordings) would favour WavPack or FLAC. Another
user, looking for the very highest compression available, would go with
OptimFrog. Someone wanting portable support would use FLAC, and so on.
En fin, this is not a matter worth getting too worked up about. If you
later find out the codec you chose isn't the best for your needs, you
can just transcompress to another format, without risk of losing quality.
* Encoding speed, Decoding speed and Compression ratio are based on each
encoder's default settings.
** Flexibility refers to the amount of encoding choices offered to the
users (Fast/low compression, Slow/high compression and everything inbetween)
These are the most popular lossless codecs, in alphabetical order:
http://www.apple.com/itunes/import.html - Apple Lossless Audio Codec
ALAC is a codec developed by Apple for usage in iPod and AirPort Express.
PROS
- Very fast decoding
- Open source (http://craz.net/programs/itunes/alac.html)
- Hardware support (iPod, AirPort Express)
- Streaming support
- Tagging support (QT tags)
- Excellent hardware-software-lossy format integration with iTunes/iPod.
CONS
- Closed source (encoding)
- Few software support (iTunes)
- Doesn't support multichannel audio and high resolutions
- Compression efficiency not on par with other lossless codecs
- No hybrid/lossy mode
Other features
- Fits in the MP4 container
- Can be used with the AirPort Express gadget
http://flac.sourceforge.net/ - Free Lossless Audio Codec
FLAC is a lossless codec developed by Josh Coalson. It's part of the Xiph multimedia portfolio, along with Vorbis and Theora.
PROS
- Open source
- Very fast decoding
- Hardware support (Karma, Phatbox, etc.)
- Very good software support
- Error robustness
- Streaming support
- Supports multichannel audio and high resolutions
- Tagging support (FLAC tags)
- Pipe support
CONS
- Compression efficiency not on par with other lossless codecs
- No hybrid/lossy mode
- Doesn't support RIFF chunks
Other features
- Supports embedded CUE sheets (with http://flac.sourceforge.net/faq.html#general__no_cuesheet_tags)
- Includes MD5 hashes for quick integrity checking
- Fits the OGG and Matroska containers
- ReplayGain compatible
http://www.lossless-audio.com/
LA is a lossless codec developed by Michael Bevin.
PROS
- Very high compression
- Tagging support (APE tags)
- Supports RIFF chunks
- Pipe support
CONS
- Closed source
- Very slow encoding and decoding
- No hardware support
- No hybrid/lossy mode
- Bad software support
It's important to mention that the LA foobar plugin is buggy and doesn't produce lossless streams!
http://www.nue.tu-berlin.de/wer/liebchen/lpac.html
Lossless Predictive Audio Coder (LPAC) is a lossless codec developed by Tilman Liebchen. Development of it has been halted in favour of development of MPEG4 ALS.
PROS
- Reasonable compression ratios
- High resolution audio support
- Tagging
- Supports RIFF chunks
CONS
- Closed source
- No error robustness
- Slow seeking
- No multichannel support
- No hybrid/lossy mode
- No hardware support
http://www.monkeysaudio.com/
Monkey's Audio is a very efficient lossless compressor developed my Matt Ashland.
PROS
- Open source
- High efficiency
- Good software support
- Error robustness
- Java version (multiplatform)
- Tagging support (ID3v1, APE)
- High resolution audio support
- Supports RIFF chunks (only in the GUI encoder)
- Pipe support (only in a http://www.etree.org/shnutils/shntool/ version)
CONS
- No multichannel support
- No hybrid/lossy mode
- No hardware support
Other features
- Supports embedded APL sheets (similar to CUE sheets)
http://losslessaudiocompression.com/
OptimFROG is a lossless format developed by Florin Ghido to become the champion in audio compression.
PROS
- Very high compression
- Good software support
- Error robustness
- Streaming support
- Supports high resolutions
- Hybrid/lossy mode
- Tagging support (ID3, APE)
- Supports RIFF chunks
CONS
- Closed source
- No multichannel audio support
- No hardware support
- Quite slow decoding
Other features
- Supports 32bit float streams
- Includes MD5 hashes for quick integrity checking
- ReplayGain compatible
http://www.realnetworks.com/products/codecs/realaudio.html
RealAudio lossless is the lossless codec developed by Real Networks for their multimedia portfolio
PROS
- Very fast decoding
- Streaming support
CONS
- Closed source
- No multichannel and high resolution audio support
- Few software support (Real Player)
- No hardware support
- Compression efficiency not on par with other lossless codecs
- No hybrid/lossy mode
- No pipe support
http://www.etree.org/shnutils/shorten/
Shorten is a very old and featureless lossless codec developed by Tony Robinson at SoftSound.
PROS
- Open source
- Fast decoding
- Very good software support
- Supports RIFF chunks
- Pipe support
CONS
- Quite inefficient
- No multichannel or high resolution audio support
- No hybrid/lossy mode
- No error robustness
- Not streamable
- No hardware support
- No native tagging
http://tta.corecodec.org/
TTA is a new lossless codec developed by a team of russian programmers.
PROS
- Open source
- Good efficiency (not as good as Monkey's or OptimFrog, but not as bad as SHN or ALAC)
- Hardware support (obscure DVD player)
- Supports multichannel audio and high resolutions
- Tagging support (ID3v2)
CONS
- No streaming support
- No hybrid/lossy mode
- Doesn't support RIFF chunks
- No pipe support
Other features
- Fits the Matroska container
- ReplayGain compatible
http://www.wavpack.com/
WavPack is a fast and featureful lossless codec developed by David Bryant.
PROS
- Open source
- Very fast decoding
- Good efficiency (not as good as Monkey's or OptimFrog, but not as bad as SHN or ALAC)
- Error robustness
- Streaming support
- Supports multichannel audio and high resolutions
- Hybrid/lossy mode
- Tagging support (ID3v1, APE)
- Supports RIFF chunks
- Hability to create self extracting files for Win32 platform
- Pipe support
CONS
- No hardware support
- Average software support (Winamp plugin, Foobar, dbPowerAMP, Nero)
Other features
- Supports embedded CUE sheets
- Includes MD5 hashes for quick integrity checking
- Can encode in both symmetrical and assymmetrical modes.
- ReplayGain compatible
http://www.microsoft.com/windows/windowsmedia/9series/codecs/audio.aspx
WMA Lossless is the lossless codec developed by Microsoft to be featured in their Windows Media codec portfolio.
PROS
- Streaming support
- Very good software support
- Supports multichannel audio and high resolutions.
- Tagging support (proprietary)
CONS
- Closed source
- No hybrid/lossy mode
- No hardware support (but it's likely to appear sooner or later)
- Doesn't support RIFF chunks
Other features
- Fits the ASF container
Some links to lossless format compression comparisions:
http://web.inter.nl.net/users/hvdh/lossless/lossless.htm
http://members.home.nl/w.speek/comparison.htm
http://foobar2000.net/lossless/ - comparing only classical music.
Big thanks to every forum member that contributed to this comparision with information about codecs, feature comparisions, benchmarks, etc.
I welcome user comments and corrections on the entries.
==========================================================================================================
以下是部分节选的评论：
Posted by: kurtnoise Nov 26 2004, 07:44 AM
Some notes about RALF :
I made some quick tests with Helix Producer to see the behaviours of
this lossless codec with some others...Why Helix Producer : because
there are 3 encoding modes whereas in RealPlayer it's only one. So,
according to my results I'll be much less enthousiast like kotrtim...
The method that I used is the same as http://members.home.nl/w.speek/comparison.htm.
For the Real Audio Lossless, I extracted my wave files with EAC and
then encoding with Helix Producer. Decoding has made by RealPlayer 10.
I created some tables to observe different results (it's in French,
but I think it's readable.) BTW, some Hints : vitesse d'encodage ==
Encoding Speed ; vitesse de d閏odage == Decoding Speed ; Ratio de Compression
== Compression Ratio ; Taille == Size. 
Global Results:
Sample 1: (En Quarantaine_Miossec (extract of "1964" album)
/ Duration = 2''29 ) // Hint : french pop rock
Sample 2: (Sample 2 : Rock el Casbah_Rachid Taha (extract
of "T閗itoi ?" album) / Duration = 4''33.) // Hint : rock.
Sample 3: (Mouth's Cradle_Bj鰎k (extract of "Med鷏la" album)
/ Duration = 4''01.) Hint : electro.
Sample 4: (Symphony n? (Sehr Beh鋑lich)_Gustave Malher
/ Duration = 1''52.) // Hint : classic.
Tests made on Pentium 3 800 Mhz & 512 Mo RAM. I hope that help somebody.
本页网址二维码：