Prof Yaffle wrote:
> I'm not aware of a way internally to tvheadend to trigger transcoding via an external process - only the internal transcoding support.
Thank you for the reply. I don't even know how that works or what it is capable of. Is there any really good documentation on that, or an article explaining it somewhere?
> I suppose you could have an external process running that looks for a file (i.e. a recording starting) and then starts to transcode it. I can imagine timing would be an issue, though... if it's faster than realtime, you'll have to buffer it in some way as it would run out of source material, and if it's slower than realtime then it'd be unwatchable (if that's the goal). I can image that trying to do comskip on a file that isn't yet complete would have similar challenges.
Okay. I thought perhaps that ffmpeg could handle streams in real time (as an example of the type of post that leads me to believe it may be possible, see this one posted just today: https://ffmpeg.org/pipermail/ffmpeg-user/2014-December/024563.html - I don't have the slightest clue what he's doing there, but it's stumbling across messages such as that one that led me to think that perhaps ffmpeg could be used in this way, but maybe I'm totally wrong).
> Let me check to see if anyone can confirm the 'PPA has transcoding enabled' angle. You shouldn't
have to compile it yourself... if necessary, I'll build you a couple of debs that definitely have support built-in, and you can try those.
>
> It really is easy to compile your own, though, so I'm happy to talk you through that if you're brave enough to try again.
Well if this were exclusively my system I might be willing to try that, but in this case that's not exclusively my decision, and because it's already running an unstable version of TVHeadEnd and it's actually working (after something like four months of on and off batting our heads against a brick wall to try and get it to work reliably - I don't mean it took four months with TVHeadEnd, just to get a backend system working in general), now that it's actually working fairly reliably we are very reluctant to even do a normal upgrade on TVHeadEnd until we can figure out a good way to back up this system (can you tell that neither of us are really Linux guys?).
> (Regarding speed of conversion - converting audio is pretty quick, converting video typically isn't unless it's to something low quality, and re-arranging streams or re-packaging them into a different container is as fast as reading in a file from end to end).
I realize that, which is why I was only curious whether this could be done when the audio stream rearrangement is necessary. Just so you understand, here is the real problem. The audio is sent in three separate streams that each contain two channels:
Stream 1: Left and Right Front audio
Stream 2: Center and Low frequency audio
Stream 3: Left and Right surround audio
There is also a fourth audio stream that contains alternate language/described video material but I don't need that.
Most of the dialog (speech) is on the center channel and NOT the left or right front channels. I found an article that shows how to get all these streams into a single ac3 stream using ffmpeg, mapping them to the proper channels in 5.1 format. If there is a way to do this in TVHeadEnd without using ffmpeg I would be happy to give it a try, but I don't think there is.