tsMuxeR, M2TS and audio delay

[Ghitulescu]

I hope this is the right thread :rolleyes:

My Humax outputs .M2TS files for both resolutions (SDTV and HDTV). I'm not a big fan of Tele5, but I have from time to time some recordings of its programmes.

Now the problem.
I remux to .TS with tsmuxergui (you put the capitals wherever you like :p) then convert the result into MPEG2 (this goes to cutting then authoring). Tele5 has usually a delay of at least 500ms for audio (the delay is automatically corrected by the MPEG2 converter if and only if it starts from an original .TS). Somehow tsmuxergui manages to "loose" the delay info from the converted stream, so all my recordings will have the audio shifted because the MPEG converter receives a 0 ms delay.

Is there any solutions how to:

make tsmuxergui respect the audio delay
make tsmuxergui inform me about this delay (ms, frames etc.) so I can use it later on
use maybe another software (does PjX takes into account or automatically corrects the audio delay? - I can do it by hand, but only if I know the delay beforehand)
other ideas?

Thanx

[turbojet]

Have you tried demuxing the audio with DGMPGDec/DGAVCDec to get the delay?

[Ghitulescu]

Forgive my ignorance, but I thought this software is a frameserver to Avisynth/vdub. I don't (principially) do transcodings.

I don't need separate streams as my MPEG2 cutter wants MPEG files.

In one of the threads of this forum, the owner/creator of this software, neuron2, publicly announced his determination for am .M2TS cutter (also for H.264 streams). I'll sit and wait (and probably buy another external HDD :().

[midnightsun]

my findings are that tsmuxer discards all audio (if original audio delay in the file is negative) before the first video frame so that the new audio will be as close as possible to being aligned with video. In any case, if you remux a TS (or M2TS or whatever) and reopen it with tsmuxer and check the audio stream's properties it will list a delay, which can be 0-31ms since I'm assuming you're working with 25f/s footage off TV. If you have a way of instructing your next software in the chain, that is the value you're looking for.

[turbojet]

DGDecode tools are more than a frameserver, they're also simple analysis and demuxer. If you open the TS, demux audio, stop after a second you will see get an audio file that lists the delay (example: track_01_DELAY -500ms.ac3) which is almost(?) always accurate. It's another step to the process but by far the quickest and most accurate way currently.

[Ghitulescu]

I've checked yesterday another file, this time from Das Vierte (http://www.das-vierte.de/), it has a -198ms audio delay, and it seems that tsmuxergui identified it and passed this info into the command line (according to the info at the bottom of its window).

However, the result is still desynch, probably with that ~200ms amount.

It seems that negative delays for audio are not taken into consideration in any muxers I've tried (I addressed once this issue also in IfoEdit, still no answers).