Lossless

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Unlike lossy compression, lossless is a mathematically perfect way of representing your audio data. After decompression, you will have a bit-perfect copy of your original wave file - just as the name states, it is without loss. You can think of the various lossless compressors as highly tuned versions of Winzip or Winrar that are specifically for audio.


Lossless compression explained

Popular lossless formats


Oddball Formats

There are several old lossless formats that aren't really deserving of having an article all for themselves. Reasons are: lack of widespread support, lack of features, bad efficiency and, most importantly, it seems noone is really interested in them.

Most of those would have disappeared by now, but they are being preserved for posterity at rjamorim's ReallyRareWares


Advanced Digital Audio (ADA)
Marian's a-Pac
AudioZip
Bonk
Dakx WAV
LiteWave
Pegasus SPS
RKaudio
Split2000
Sonarc
VocPack
WavArc
WaveZip/MUSICompress


Note that currently no single format can be considered best for all applications. Rather, the best format depends on the intended use, as well as a number of other factors (such as licensing and file structure). For example, Shorten and FLAC are widely used for sharing live music because of their cross-platform support and speed. Monkey's Audio is popular among Windows users for its superior compression ratio.

Lossless compressors comparisons (note the specific assumptions and limitations of each comparison; in particular, results are sensitive to the music selected):

http://web.inter.nl.net/users/hvdh/lossless/lossless.htm 
Includes an interesting graph of encode/decode speeds vs. file size on the All Albums page
Lossless comparison 
A comparision focusing more on codec features and less on absolute encoding efficiency. Also features a table comparing most popular codecs based on their features.
http://home.wanadoo.nl/~w.speek/comparison.htm 
Performance Comparison of Lossless Audio Compressors - Compares file size, encode speed, decode speed for APE, FLAC, LPAC, WavPack, Shorten (SHN), RKAU, OptimFROG, LA, WMA Lossless. Updated 5-2003
http://www.firstpr.com.au/audiocomp/lossless/ 
Includes a variety of notes, but the testing was completed in 2000, making the results largely obsolete.

See Also