AAC
        The MPEG2 / MPEG4 audio codec. Comparable to Vorbis.
        
            Options
            
                - 
                    Bitrate (number)
 Set a specific bitrate to control file size. Default is 128000.
 bitrate=196000
 
- 
                   Profile>
 Set the AAC encoding profile.
 
                       - 1: Main profile
- 2: Low complexity profile (worst, default)
- 3: Scalable sampling rate profile
- 4: Long term prediction profile (best)
 profile=4