[FFmpeg-user] Can I use ffmpeg to combine audio streams in .ts file?

[skyscanner at gmx.ca]

On Tue, 30 Sep 2014 10:45:37 +0200, barsnick at gmx.net wrote:

> Since you have already built an understanding of what you want to
> combine in which way, this page should give you some hints and examples
> of how to achieve that:

> https://trac.ffmpeg.org/wiki/AudioChannelManipulation

> Note that it goes beyond pure mapping, using e.g. the amerge and pan
> filters.

Thank you, but I actually found that page a couple of days ago and it was not at all helpful to me for a couple of reasons. First, I am REALLY new to ffmpeg and don't yet understand how all the options work and interrelate, in fact I have the nagging feeling that the way I did use the options was probably not the best way, but ffmpeg is a VERY complex program and it's hard to figure out the "correct" way to do something like this.

But also, all of the examples on that page are for a single stream. Every single example only mentions "stream 0" - there is no reference anywhere to a "stream 1", "stream 2", etc. That is why I am beginning to wonder if ffmpeg even has the capability to merge streams. I have looked at a lot of pages on ffmpeg, some of which make some sense to me and many which didn't, but the common thread is that I could not find a single example anywhere of multiple streams being mixed down to a single stream or to fewer streams. The channel mapping is only a secondary concern to me and it's not going to bother me that much if I never get true 5.1, but not being able able to hear all the audio is the big issue now.

Also that page seems to be dealing with audio files only, not video, and even in the example for "2 × stereo → stereo" is talking about starting with two .wav files and converting them to a single .mp3 file. Once again, nothing at all is said about merging multiple audio streams from the same .ts file. So if you know of any examples of merging audio streams in files with video and audio present, that's what I really need to see right now.