[FFmpeg-user] transcode / segment h.264 aac audio

[Joel B]

I have a version of ffmpeg that is distributed with Subsonic server, the current version of which can transcode and stream video in real time to iPhone/iPad/Roku/etc.  By default it transcodes the audio portion of the video to mp3. I want to alter the command line if possible to transcode to aac without the users having to compile their own version. As I understand it there is an AAC encoder built into ffmpeg. ffmpeg -codecs gives me two options aac and aac_latm

so far if I use either of those, I don't seem to get any playable segments, just an endless stream of the following on the server console:

[2013-01-26 17:18:38,937] INFO PlayQueueInputStream - admin listening to "Day of the Triffids/DayOfTheTriffids.avi"
[2013-01-26 17:18:38,941] DEBUG TranscodeInputStream - Starting transcoder: [/Library/Application Support/Subsonic/transcode/ffmpeg] [-ss] [0] [-t] [10] [-i] [/Users/admin2/Music/iTunes/iTunes Music/aMOVIES/Day of the Triffids/DayOfTheTriffids.avi] [-async] [1] [-b] [553k] [-s] [536x240] [-ar] [44100] [-ac] [2] [-v] [0] [-f] [mpegts] [-vcodec] [libx264] [-acodec] [aac_latm] [-preset] [superfast] [-threads] [0] [-] 
[2013-01-26 17:18:39,100] INFO PlayQueueInputStream - admin listening to "Day of the Triffids/DayOfTheTriffids.avi"
[2013-01-26 17:18:39,104] DEBUG TranscodeInputStream - Starting transcoder: [/Library/Application Support/Subsonic/transcode/ffmpeg] [-ss] [10] [-t] [10] [-i] [/Users/admin2/Music/iTunes/iTunes Music/aMOVIES/Day of the Triffids/DayOfTheTriffids.avi] [-async] [1] [-b] [553k] [-s] [536x240] [-ar] [44100] [-ac] [2] [-v] [0] [-f] [mpegts] [-vcodec] [libx264] [-acodec] [aac_latm] [-preset] [superfast] [-threads] [0] [-] 
[2013-01-26 17:18:39,328] INFO PlayQueueInputStream - admin listening to "Day of the Triffids/DayOfTheTriffids.avi"
[2013-01-26 17:18:39,334] DEBUG TranscodeInputStream - Starting transcoder: [/Library/Application Support/Subsonic/transcode/ffmpeg] [-ss] [20] [-t] [10] [-i] [/Users/admin2/Music/iTunes/iTunes Music/aMOVIES/Day of the Triffids/DayOfTheTriffids.avi] [-async] [1] [-b] [553k] [-s] [536x240] [-ar] [44100] [-ac] [2] [-v] [0] [-f] [mpegts] [-vcodec] [libx264] [-acodec] [aac_latm] [-preset] [superfast] [-threads] [0] [-] 

The command line looks like this if you remove the [ and ] brackets:

/Library/Application Support/Subsonic/transcode/ffmpeg -ss 560 -t 10 -i /Users/admin2/Music/iTunes/iTunes Music/aMOVIES/Day of the Triffids/DayOfTheTriffids.avi -async 1 -b 553k -s 536x240 -ar 44100 -ac 2 -v 0 -f mpegts -vcodec libx264 -acodec aac_latm -preset superfast -threads 0 -

I also compiled a version of ffmpeg with libvo_aacenc which gives me about 10 seconds of audio playback before FFMPEG completely locks up my mac unless I manage to kill -9 before it is too late.

Is there some way to get a decent audio transcode with ffmpeg to segmentable AAC audio without compiling a nonfree codec? 

Failing that, is there a way to just use the existing audio which in many cases is already in aac format?

  - Joel