Streaming uses much more bitrate than necessary

Trond Michelsen

Hi.

I'm using TVHeadend 3.9.373, and I recently discovered that when streaming radio channels, tvheadend will send a lot more data than necessary. Usually between 2 and 3 Mbps, even if the radio channel only requires 64kbps.

It seems that I'm getting the full mux, except the actual video/audio streams from the other channels.

The behavior is the same when streaming and recording TV-channels as well, but the overhead is less of a problem in those situations.

I assume this isn't how it's supposed to work. I've also had a quick look at some old recordings, and it definately didn't behave like this before.

Is this possibly a config option I've accidentally enabled, or is it a bug?

Adam Sutton

Just to re-iterate what I said on IRC. This is my doing, it's intentional (at least partly).

We enabled passing thru of useful metadata tables to the TS passthru muxer. This includes things like the NIT, SDT and EIT tables. This is probably where all the "extra" service listings come from, there not there, just the metadata that defines them.

However the EIT table could be fairly large for a mux carrying that many services if its 7 days. Really what we actually want (in the recordings) is just EITpf, but filtering that requires a lot more work than we really want in the passthru muxer. Therefore the decision was taken not to bother.

However I do appreciate that we probably need the option to disable this, particularly for streaming where that info is less likely to be needed. But I've just not had time to do this. If it was really affecting you it's probably not that hard to hack the code to remove those tables from the streams.

Adam