Lossless audio compression comes in a variety of forms. By definition, since all of these formats are lossless, technically there should be no difference in audio quality between them. The significant difference lies in the way they are compressed, which some say affects audio quality in different ways. WMA and FLAC files have some advantages and disadvantages, depending on the context.
WMA Lossless format
The Windows Media Audio format is one of several common lossless formats out there. It was originally designed to compete with the MP3 format, which lacks the full digital rights management capabilities of the WMA format. It is comparable to other proprietary lossless formats in its ability to support multi-channel audio and high-resolution recordings. WMA uses a unique compression algorithm that is sometimes claimed to provide better quality audio than other lossless formats. However, since “lossless” is by definition an identical reproduction of an original source, the superiority of the WMA format is questionable.
FLAC format
The free lossless audio codec was originally created by Josh Coalson in 2000 and has since become a common format in lossless audio playback. Like the Apple Lossless format, the FLAC format is open source and can be used and expanded as desired. The tools for creating and editing FLAC files are freely available. A major limitation of the format is its lack of compatibility with many proprietary digital audio devices and applications. However, support for the FLAC format has grown considerably, especially in the area of audio transmission.
Proprietary and open source
The most significant difference between the WMA and FLAC formats is their use, or lack thereof, of digital rights management technology. WMA is a proprietary format owned by Microsoft and requires a license to implement it. Despite this limitation, it is among the most popular codecs in use and can be played with a wide variety of devices and applications. The FLAC format has the advantage of being freely available for use, but the widespread presence of the WMA format is lacking. The preferred format will always depend on the context in which the file will be used.
Audio quality
Technically, all lossless audio codecs should offer identical audio qualities. However, it is occasionally argued that the different compression methods used result in subtle differences. The WMA codec uses two types of compression on a single file, depending on the complexity of the audio it contains. The result is less compression on complex passages and more compression on less complex regions, said to provide smoother quality than the other codecs. The FLAC compression algorithm is much simpler and compresses all audio files in the same way. If this results in a difference in the quality of the WMA codec, it is probably not detectable by the human ear.
