The following is a list of the defined media_type values, as of BeOS R5 (taken from the BeBook)

• B_MEDIA_NO_TYPE : Typeless media data.
  
• B_MEDIA_UNKNOWN_TYPE: Unknown media type.
  
• B_MEDIA_RAW_AUDIO : Uncompressed, linear audio.
  
• B_MEDIA_RAW_VIDEO : Uncompressed, linear video.
  
• B_MEDIA_VBL : Raw data from VBL area.
  
• B_MEDIA_TIMECODE : Timecode data. Undetermined format.
  
• B_MEDIA_MIDI : MIDI data.
  
• B_MEDIA_TEXT : Text data; typically closed-captioning information.
  
• B_MEDIA_HTML : HTML data.
  
• B_MEDIA_MULTISTREAM : Multi-stream media data, such as AVI or QuickTime.
  
• B_MEDIA_PARAMETERS : BControllable change data.
  
• B_MEDIA_ENCODED_AUDIO : Encoded audio (such as AC3 or DTS).
  
• B_MEDIA_ENCODED_VIDEO : Encoded video (such as Indeo or MPEG).
  
• B_MEDIA_PRIVATE : Base value for private Be media types.
  
• B_MEDIA_FIRST_USER_TYPE : Base value for user-defined media types.
  

In addition to these, the following additional types are suggested for possible inclusion in future MediaKit implementations :

• MEDIA_XML : XML data.
• MEDIA_VECTOR : Vector based image/animation formats
• MEDIA_3D : Includes OpenGL and other data related to spatial representation
• MEDIA_FFT : Streaming FFT data, (currently implemented as Private media_type in FMediaNodes.

For reference: MCF track types