wav

Though a WAV file can hold compressed audio, the most common WAV format contains uncompressed audio in the pulse-code modulation (PCM) format. PCM audio is the standard audio file format for CDs at 44,100 samples per second, 16 bits per sample. Since PCM uses an uncompressed, lossless storage method, which keeps all the samples of an audio track, professional users or audio experts may use the WAV format for maximum audio quality. WAV audio can also be edited and manipulated with relative ease using software.

Popularity

As file sharing over the Internet has become popular, the WAV format has declined in popularity, primarily because uncompressed WAV files are quite large in size. More frequently, compressed but lossy formats such as MP3, and AAC are used to store and transfer audio, since their smaller file sizes allow for faster transmission over the internet as well as lower disk space consumption. There are also more efficient lossless codecs available, such as Monkey's Audio, TTA, WavPack, FLAC, Shorten, Apple Lossless and WMA Lossless.

The usage of the WAV format has more to do with its simplicity and simple structure, which is heavily based on the IFF file format. Because of this, it continues to enjoy widespread use with a variety of software applications, often functioning as a lowest common denominator when it comes to exchanging sound files between different programs.

Limitations

The WAV format is limited to files that are less than 4 GB in size, due to its use of a 32 bit unsigned integer to record the file size header (some programs limit the file size to 2 GB). Although this is equivalent to about 6.6 hours of CD-quality audio (44.1 kHz, 16-bit stereo), it is sometimes necessary to go over this limit. The W64 format was therefore created for use in Sound Forge. Its 64-bit header allows for much longer recording times. This format can be converted using the libsndfile library. The RF64 format specified by the European Broadcasting Union has also been created to solve this problem.

Audio CDs

Audio CDs do not use WAV as their sound format, instead using Red Book audio. The commonality is that both audio CDs and WAV files have the audio data encoded in PCM. WAV is a data file format for computer use. If one were to transfer an audio CD bit stream to WAV files and record them onto a CD-R as a data disc (in ISO format), the CD could not be played in a player that was only designed to play audio CDs.

See also

• BWF, Broadcast Wave Format
• RF64, An extended File Format for Audio (multichannel file format enabling file sizes to exceed 4 Gbyte)

External links

• A summary of the WAVE file format
• Another summary of WAVE file format
• Wotsit's file format information for WAV
• WAV file format
• Basic WAV file format
• Borland C program to convert Audio Cds in Wave Files