bash-3.1$ mplayer -afm help
MPlayer 1.0-1.rc1.11mdv2007.1-4.1.2 (C) 2000-2006 MPlayer Team
CPU: Intel(R) Pentium(R) 4 CPU 2.26GHz (Family: 15, Model: 2, Stepping: 9)
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
98 audio & 216 video codecs
Available (compiled-in) audio codec families/drivers:
    afm:    info:  (comment)
   mp3lib  MPEG layer-2, layer-3 (Optimized to MMX/SSE/3Dnow!)
   liba52  AC3 decoding with liba52
    hwac3  AC3/DTS pass-through S/PDIF
    hwmpa  MPEG audio pass-through (fake decoder) (For hardware decoders)
   ffmpeg  FFmpeg/libavcodec audio decoders
      pcm  Uncompressed PCM audio decoder
   dvdpcm  Uncompressed DVD/VOB LPCM audio decoder
     alaw  aLaw/uLaw audio decoder
 imaadpcm  IMA ADPCM audio decoder
  msadpcm  MS ADPCM audio decoder
 dk3adpcm  Duck Corp. DK3 ADPCM decoder
    msgsm  native GSM/MSGSM audio decoder
    dshow  Win32/DirectShow decoders
      dmo  Win32/DMO decoders
      acm  Win32/ACM decoders
      vqf  TWinVQ decoder (Ported from MPlayerXP)
  qtaudio  QuickTime Audio Decoder (uses win32 quicktime DLLs)
libvorbis  Ogg/Vorbis audio decoder
    speex  Speex audio decoder
   libmad  libmad mpeg audio decoder (based on Xine's libmad/xine_decoder.c)
  realaud  RealAudio decoder (binary real audio codecs)
    libdv  Raw DV Audio Decoder
   mpcdec  Musepack audio decoder