OP25 Output Audio to Files with OP25?

[nokoa3116]

Is it possible to output op25 rx p25p2 audio to individual audio files?

I use boatbod's OP25.

SDR Trunk, and Trunk Recorder are able to do this when monitoring a whole system, but those just never work well, it often goes garbled, OP25 is much more stable while it is monitoring a single channel at a time, it provides high quality audio, without cutting, and without garble. I am aiming for quality, and no loss or missed transmissions. Reason I want individual audio files was to integrate it into UIs and archive transmissions more easily. In addition some tdma p25p2 talkgroups that are extremely quiet from OP25, and using the live gain distorts the sound in order to achieve good enough volume. I was gonna look into running those files through audio softwares that will correct that. Still experimenting on that topic.

I do news in the San Francisco Bay Area, and use these programs heavily for my lossless monitoring, I listen to their traffic everyday most of the day. Quality is important for me in order to properly understand addresses, and volume needs to be consistent among all talkgroups that are playing at the same time. I also use Trunk Recorder, and SDR Trunk for archives, so I can listen back to things I missed, but as mentioned they don't work well enough for me, and my conditions. I also have an SDS100 monitoring. System monitored is SVRCS.

 

[wgbecks]

Yes it is possible to do this using the "-L LOGFILE_WORKERS, --logfile-workers=LOGFILE_WORKERS" option with rx.py noting that this is an all or none proposition. That is you either dump audio to the speaker or to a stream else you dump them to .wav files.

Note that use of this option does require an SDR that has enough bandwidth to cover the the entire spectrum of the desired system from its lowest to highest frequencies in use. This also puts a tremendous demand upon the CPU and other resources that have to be considered should you consider using this option.

Perhaps @boatbod will chime in with some specifics. But this explanation is how the -L LOGFILE_WORKERS basically functions and I want to recall (but don't quote me) that Trunk Recorder was based upon this foundation contained in op25.

 

[boatbod]

Perhaps @boatbod will chime in with some specifics. But this explanation is how the -L LOGFILE_WORKERS basically functions and I want to recall (but don't quote me) that Trunk Recorder was based upon this foundation contained in op25.

I don't have a lot to add except to not that the logfile_workers option is a legacy piece of code which I personally haven't spent any time looking working on or maintaining. If it still works that's great, but I wouldn't bet my paycheck on it!

 

[wgbecks]

It has been quite some time since I last tested (used) the -L LOGFILE_WORKERS on boatbod's op25 version. I decided to test it with a previous configuration file made several years ago and its no longer working. However, I did have luck with the Osmocom (Max's) version of op25 when I last tested it about eight or nine months ago.

What I might suggest as a better alternative is to go with SDRTrunk that when combined with a wide bandwidth SDR like the Airspy Mini or R2 you can setup user options to create audio (.wav) recordings for user specified TG's identified in the Alias setup section under the Playlist editor.

Bill

 

[nokoa3116]

Thank you both for the replies. I set up multi_rx with OP25 and so far it works much better than Trunk Recorder, which I know is based on OP25, and better than SDR Trunk, with quality. I want to save audio files from multi_rx. I don't think I can use -L as I cannot have the whole system decoded as it's a very busy system, with busses, trains, public works, as well as public safety. My CPU won't be able to handle it.

I have 5 SDRs, but for this setup I use just a single Airspy Mini. Both SDRTrunk, and Trunk Recorder produce garbled transmissions sometimes, I have tried many different setups, with different antennas, at different locations. While OP25 just works much better. Is there a feature to save into individual files from multi_rx, or is it the same deal as from the regular rx? I wrote a silly program that listens to icecast2 streams and saves a file whenever there is activity. But I am not good at this so my program is extremely resource hungry. I was wondering if there is an easy way to add this as a feature?

 

[boatbod]

Thank you both for the replies. I set up multi_rx with OP25 and so far it works much better than Trunk Recorder, which I know is based on OP25, and better than SDR Trunk, with quality. I want to save audio files from multi_rx. I don't think I can use -L as I cannot have the whole system decoded as it's a very busy system, with busses, trains, public works, as well as public safety. My CPU won't be able to handle it.

I have 5 SDRs, but for this setup I use just a single Airspy Mini. Both SDRTrunk, and Trunk Recorder produce garbled transmissions sometimes, I have tried many different setups, with different antennas, at different locations. While OP25 just works much better. Is there a feature to save into individual files from multi_rx, or is it the same deal as from the regular rx? I wrote a silly program that listens to icecast2 streams and saves a file whenever there is activity. But I am not good at this so my program is extremely resource hungry. I was wondering if there is an easy way to add this as a feature?

rx.py and multi_rx.py work similarly in the way they stream their decoded audio. There may be a way to stream to file using liquidsoap as an intermediary, but I haven't explored how you would write the .liq script.