Hum, this is a wild guess, but the sox aspect reinforced it: somewhere, there's a network buffer overflowing. If that interpretation is right, sox just adds a quickly-absorbing buffering layer to the processing chain.
In any case, would sound like the pipe approach would be best. Is there a reason not to use it? Maybe we can come up with a way to make whatever it is work :) Best regards, Marcus On Fri, 2019-05-24 at 13:29 +1000, Ignatius Rivaldi wrote: > sox is the magic thing that makes netcat and multimon-ng works. Even > if I don't do any resampling, ie sox -t raw -esigned-integer -b 16 -r > 22050 - -esigned-integer -b 16 -r 22050 -t raw - and use the UDP > channel from the resampled audio it works, while if I in I pipe > netcat directly into multimon-ng it doesn't work > > On Fri, May 24, 2019 at 1:24 PM Ignatius Rivaldi > <minecraft2...@gmail.com> wrote: > > Its the UDP sink. If I use File Sink to a named pipe file multimon- > > ng > > can decode it by using cat pipe | multimon-ng -Aq - but if I use > > the > > UDP port and netcat -ulk localhost 8000 | multimon-ng -Aq - it > > doesn't > > decode, so the resampler does work but somewhere in the UDP channel > > something corrupts the data > > > > On Sun, May 19, 2019 at 1:50 AM Kevin Reid <kpr...@switchb.org> > > wrote: > > > On Sat, May 18, 2019 at 12:07 AM Albin Stigö < > > > albin.st...@gmail.com> wrote: > > > > You need to use a low pass filter (taps) in you resampler. Look > > > > at the spectrum after the resampler and this will be obvious to > > > > you. A lowpass filter with a cutt off at 3-4kHz or so should do > > > > it. > > > > > > This cannot be the problem, because rational_resampler > > > automatically calculates a filter if taps are not specified: > > > https://github.com/gnuradio/gnuradio/blob/4e4f44c726556496c420bceb87ccafe6843916f7/gr-filter/python/filter/rational_resampler.py#L107 > > > > > > (I also checked the GRC file, and the fractional bandwidth is > > > also None (auto-set) despite appearing as "0" in the screenshot.) > > > > > > Unfortunately, I don't have any ideas what the problem is. For > > > what it's worth, I have successfully integrated multimon-ng into > > > a flow graph ( > > > https://github.com/kpreid/shinysdr/blob/master/shinysdr/plugins/multimon.py > > > ) but the code is very differently structured so it would be hard > > > to transfer the knowledge into GRC. > > > > > > As a next troubleshooting step I would recommend adding GUI sinks > > > at various parts of the flow graph so that you can check the > > > signal integrity. (For an example, consider adding after the > > > float-to-short a short-to-float and QT GUI Sink — to ensure the > > > signal hasn't gotten lost in quantization noise and just needs to > > > be amplified before converting to short, as well as checking that > > > the bandwidth/resampling is good.) > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
