OP25 boatbod op25 audio number of channels

[k7dq]

two questions about the audio section of the multi_rx.py json. 1st- number_channels - what is this and what can it be used for? 2nd - I have heard some broacast streams where the left channel is one set of trunk groups or systems and the right channel is another. Is that something done in the json or later in broadcast software.
Thanks.,

 

[wgbecks]

I am hoping that @boatbod will spot your post and provide a correct response to your first question regarding the "number of channels"
selection when configuring the audio section of a multi_rx.py json file. I almost exclusively utilize Liquidsoap for my audio processing and
streaming applications and haven't used the sockaudio module for a very long time. However, I want to recall that it was necessary to specify
two channels when setting up a Voice Channel to receive DMR transmissions.

With regard to your second question (setting up stereo broadcast streams), there are no internal provisions to stream directly to an
Icecast type server from within op25. Instead, for example, you'd configure two Voice Channels (VC's) in your json having different UDP
destination ports. Then, using Liquidsoap, you build two input sources to receive these two independent channels from op25 and process
them into left and right audio channels going to the desired Icecast server. IE: BCFY.

For additional reference, see this example of setting up an OP25 stereo stream using Liquidsoap.

 

[boatbod]

wgbecks is correct that number_channels refers to a DMR-specific op25 capability to stream the two TDMA timeslots simultaneously to left and right channel respectively, versus streaming the content of a single timeslot to both channels.