Thanks. I have been experimenting all day and comparing to reference streams 
and 4 seems to be the correct number in the PAT (my ts analyzer seems to call 
it  the program_association_table).  What I am seeing in the playing back of 
the file is that there is no audio in the stream, The table entry got there, so 
vlc shows in the codec info the correct information but there is no sound and, 
on inspection with a hex editor or ts stream analyzer,  no audio packets.

It also flies thru the audio file source so I must have something set up wrong 
or the headers do not parse correctly. I looped it for now, but I think I will 
try MP3 this next attempt.

For now I need to know how to get the audio muxed in, I must of missed a step.

What I really need, in the long run will be a "NULLAudioSource" created like 
the device source so I can put in an audio channel of low bitrate total 
silence. I think the ipad will not play a stream unless it has sound and I must 
have video only. I just do not yet know what a minimalist stream of silence 
looks like.

From: live-devel-boun...@ns.live555.com 
[mailto:live-devel-boun...@ns.live555.com] On Behalf Of Ross Finlayson
Sent: Friday, December 16, 2011 1:56 PM
To: LIVE555 Streaming Media - development & use
Subject: Re: [Live-devel] mpegVersion in addNewAudioSource

In the MPEG2TransportStreamFromESSource I am adding a video and audio source.

For the addNewVideoSource the comments say mpegversion = 4 for mpeg4 and 5 for 
h264

There is no such comment for the addNewAudioSource but examples seem to use 1.  
Anyway what is the meaning and setting for this argument.

It is used to compute the value of the "stream_type" field that gets put in the 
PMT (Program Map Table) in the resulting Transport Stream.  This value depends 
upon the specific type of video or audio (i.e., upon the specific video or 
audio codec) that's used in the file.

Because you're trying to store AAC audio in your Transport Stream, the 
"mpegVersion" field should definitely *not* be 1 or 2.  You should, instead, 
use a "mpegVersion" of 4 (because AAC is "MPEG-4 audio").

Our code will use this to compute a "stream_type" of 0xF, which may or may not 
be correct for AAC audio.  (If it's not correct, then someone please let me 
know, and I'll update our code accordingly.)


I am trying to go from H264 received from RTSP earlier and the test.aac file 
into a transport stream.

If, instead, you were to use a MP3 file for your audio (rather than an AAC 
file), then you would use a "mpegVersion" of 1 or (more likely) 2, and that 
would probably work OK.

Ross Finlayson
Live Networks, Inc.
http://www.live555.com/

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