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I have a file with mpeg-4 video and aac audio elementary streams in a mpeg-2 program stream (*.mpg)
The vlc player does not recognize the mp4 video elementary stream and the aac audio (es-stream).

It should read the program stream map especially the steam_type tag to determine the type of es.
(see http://www.atsc.org/standards/Code_Point_Registry.pdf page 14)

link to video: http://www.benjaminschuele.ch/video-m4- ... -m2-PS.mpg

With installed codecs the windows media player does play it.


any ideas?

debug output:

Hi,

Do you have more information on the file ? What tool created it ?

I have looked at it. It seems bad formated to me: the "System Header is incomplete" and so hide the PSM that is behind it.

A hex dump gives:

[1] 00 00 01 BA 5E 0B EE 3F 94 01 00 A3 D7 F8
[2] 00 00 01 BB 00 06
[3] 00 00 01 BC 00 13 E1 FF 00 00 00 10 10 C0 00 03 1B 01 F5 11 C0 00 03 1C 01 00 81 BF 3D 5D
[4] 00 00 01 E0 ....

[1] Is the pack header.
[2] Is the beginning of the "System Header" BUT the payload is missing (6 bytes).
[3] Is the "PSM" but VLC does not see it as it is taken as the System Header payload. You can also see that the size advertised by the header is shorter than the payload by 5 bytes. (Maybe a mix up in the generation tool ?)
[4] Is the first video packet.

Hi,

the file is from a self written muxer, taking a mpg-2 ts (from network) and mux it to ps.

you are right, the header was incorrect. I correct it and in the messages the vlc see the PSM now, but still use libmpeg2 and mpeg_audio instead of mpeg-4 video and aac audio.

new file: http://www.benjaminschuele.ch/video-m4- ... 2-PS-2.mpg

Your PSM is invalid. The ID used for the video and audio track are the same whereas they should be
0xc0 + audio_index for audio
0xe0 + audio_index for video
I would advise you to find the ISO/IEC 13818-1 to help you create valid PS.

Now, for the audio, I see that you use stream_type 0x11, is it really AAC LATM that you are using ?
If so, our current PS demuxer does not support it. If you have a valid sample, I will add support for it.

Thanks, this was a copy+paste error and I have corrected it.

new file: http://www.benjaminschuele.ch/video-m4- ... 2-PS-3.mpg

Yes, the audio is really AAC.

Thanks a lot for you help

Unless I am wrong you are using AAC encapsulated into ADTS and not into LATM.
For ADTS you must use 0x0f as stream type instead of 0x11.
Now you must be careful because you can only use MPEG-II AAC with ADTS in a PS or TS stream. If you want to have MPEG-4 AAC you must use LATM encapsulation which is a bit more complicated.

again, thanks a lot for your competent hints!
yes it is ADTS frametype.

It is new for me that MPEG-4 AAC have to use LATM. Do you now where in the ISO is it written?

The easer solution for me is to change aac encoder to mpeg-2:
Then it's clear that I have to use stream type 0x0f.
The book video demystified (4th) on page 666 say to stream type 0x0f: MPEG-2 Part 7 audio

http://www.benjaminschuele.ch/video-m4- ... 2-PS-4.mpg

You put only one pack header in the entire file. That is not valid.

An extract of ISO/IEC 13818-1 says:
"The Program Stream shall be constructed such that the time interval between the bytes containing the last bit of
system_clock_reference_base fields in successive packs shall be less than or equal to 0.7 s"

Moreover you must construct the pack header such that the SCR respect the P-STD model as described in this document.