Audio File Formats

Introduction

According to the creator, the audio formats can be divided into 4 categories: ISO-MPEG, Microsoft, Apple, and others. Here is a brief description of commonly used audio formats.

ISO-MPEG

MPEG(Moving Pictures Experts Group) is a group in ISO(International Standards Organization) dedicated to define some universal video formats. They define some audio codec also.

  • MP3 (MPEG-1 Layer 3) is a widely used audio format. Actually, it is not a file format. MP3 file consists of a raw audio stream compressed in MP3 codec and an optional ID3 tag at the begin or end of the file.
  • 3GA same as 3GP, but only contains audio stream.

Microsoft

  • WAV usually used to store uncompressed audio data.
  • WMA same as WMV, but only contains audio stream.

Apple

  • AIFF is used to store uncompressed audio data.
  • CAF is used in Apple QuickTime, iTunes and other media player and creator.
  • M4A same as MOV, but only contains audio stream.

Others

  • AU is definded by SUN, and used to store uncompressed audio data.
  • VOC Creative Labs Voice or RCA Digital Voice Recorder.
  • QCP used in some cellular telephone to record voice.
  • VOX voice file with Dialogic ADPCM codec used by computer telophony systems.
  • RA same as RM, but only contains audio stream.
  • MKA same as MKV, but only contains audio stream.
  • OGG, OGA same as OGV, but only contains audio stream.