Creating mp3 output files, Common uses for mp3, Music – Apple Compressor 3 User Manual
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Compressor provides the tools you need to create exceptional MP3 files.
MP3 is a specific type of MPEG encoding known formally as MPEG audio layer 3. MP3 uses
perceptual audio coding and psychoacoustic compression to remove all superfluous
information (specifically the redundant and irrelevant parts of a sound signal that the
human ear doesn’t hear anyway). The result is that MP3 encoding shrinks the original
sound data from a CD (with a data rate of 1411.2 kilobits per one second of stereo music)
by a factor of 12 (down to 112–128 kbps) without sacrificing very much sound quality.
Proponents of MP3 actually claim there is no sacrifice in sound quality, but audio
professionals can usually hear the difference on good equipment.
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Common Uses for MP3
MP3 is a widely adopted standard for compressed audio files, so it can be used in many
different ways, including music and podcasts.
Music
Almost every portable digital music player supports the MP3 audio format. By using the
higher bit rates, for example 256 kbps, you can create an excellent quality audio file using
a much smaller file size than with uncompressed audio.
You can also add metadata to the file so that when the output media file opens in many
players (including iTunes) the common information, such as artist, album, and so on,
appears.
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Creating MP3 Output Files
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