I am using OP25 (boatmod) with LiquidSoap on a Raspberry to decode and listen (locally) to a DMR signal. I have tried different audio processings with LiquidSoap but I am still not satisfied with the output volume, which is too low. It don't think it's a problem of the raspberry / loudspeakers because if I try to play a webradio with mplayer I can hear it well and loud.
This is my current configuration:
I tried with both normalize and normalize + compress.
Note: as you can see I wuold like also to dump the audio as mp3 file, for this reason I removed "mksafe" from the input to avoid recording also the silence between conversation.
Any advice on how to improve volume?
Thank you!
This is my current configuration:
Code:
#!/usr/bin/liquidsoap
# Example liquidsoap streaming from op25 to icecast
# (c) 2019, 2020 gnorbury@bondcar.com, wllmbecks@gmail.com
#
set("log.stdout", true)
set("log.file", false)
set("log.level", 1)
# Make the native sample rate compatible with op25
set("frame.audio.samplerate", 8000)
#input = mksafe(input.external(buffer=0.25, channels=2, samplerate=8000, restart_on_error=false, "./audio.py -x 2 -s"))
input = input.external(buffer=0.25, channels=2, samplerate=8000, restart_on_error=false, "./audio.py -s -x 4")
# Consider increasing the buffer value on slow systems such as RPi3. e.g. buffer=0.25
# Longer buffer results in less choppy audio but at the expense of increased latency.
# OPTIONAL AUDIO SIGNAL PROCESSING BLOCKS
# Uncomment to enable
#
# High pass filter
input = filter.iir.butterworth.high(frequency = 200.0, order = 4, input)
# Low pass filter
input = filter.iir.butterworth.low(frequency = 3250.0, order = 4, input)
# Normalization
#input = normalize(input, gain_max = 20.0, gain_min = -6.0, target = -13.0, threshold = -60.0)
input = compress(threshold=-18.,ratio=3.,gain=3.,normalize(input))
# LOCAL AUDIO OUTPUT
# Uncomment the appropriate line below to enable local sound
#
# Default audio subsystem
out (input)
#
# PulseAudio
#output.pulseaudio(input)
#
# ALSA
#output.alsa(input)
# dump recordings to a file
time_stamp = '%Y-%m-%d_%H.%M.%S'
output.file(%mp3, "./OUT_#{time_stamp}.mp3", input , fallible=true)I tried with both normalize and normalize + compress.
Note: as you can see I wuold like also to dump the audio as mp3 file, for this reason I removed "mksafe" from the input to avoid recording also the silence between conversation.
Any advice on how to improve volume?
Thank you!
). Perhaps someone with some more experience with Liquidsoap will answer. I tried to ask also on the Liquidsoap mailing list. If I will find a better solution I will report it here.
