import subprocess import time import os import code class dsp_plugin: def __init__(self): self.samp_rate = 250000 self.output_rate = 44100 #this is default, and cannot be set at the moment self.fft_size = 1024 self.fft_fps = 5 self.offset_freq = 0 self.low_cut = -4000 self.high_cut = 4000 self.bpf_transition_bw = 320 #Hz, and this is a constant self.ddc_transition_bw_rate = 0.15 # of the IF sample rate self.running = False chain_begin="nc localhost 4951 | csdr convert_u8_f | csdr shift_addition_cc --fifo {shift_pipe} | csdr fir_decimate_cc {decimation} {ddc_transition_bw} HAMMING | csdr bandpass_fir_fft_cc --fifo {bpf_pipe} {bpf_transition_bw} HAMMING | " self.chains = { "nfm" : chain_begin + "csdr fmdemod_quadri_cf | csdr limit_ff | csdr fractional_decimator_ff {last_decimation} | csdr deemphasis_nfm_ff 48000 | csdr fastagc_ff | csdr convert_f_i16", "am" : chain_begin + "csdr amdemod_cf | csdr fastdcblock_ff | csdr fractional_decimator_ff {last_decimation} | csdr agc_ff | csdr limit_ff | csdr convert_f_i16", "ssb" : chain_begin + "csdr realpart_cf | csdr fractional_decimator_ff {last_decimation} | csdr agc_ff | csdr limit_ff | csdr convert_f_i16", "fft" : "nc -vv localhost 4951 | csdr convert_u8_f | csdr fft_cc {fft_size} {fft_block_size} | csdr logpower_cf -70" } self.demodulator = "nfm" self.name = "csdr" try: subprocess.Popen("nc",stdout=subprocess.PIPE,stderr=subprocess.PIPE) except: print "[openwebrx-plugin:csdr] error: netcat not found, please install netcat!" def set_samp_rate(self,samp_rate): #to change this, restart is required self.samp_rate=samp_rate self.decimation=1 while self.samp_rate/(self.decimation+1)>self.output_rate: self.decimation+=1 self.last_decimation=float(self.if_samp_rate())/self.output_rate def if_samp_rate(self): return self.samp_rate/self.decimation def get_name(self): return self.name def get_output_rate(self): return self.output_rate def set_demodulator(self,demodulator): #to change this, restart is required self.demodulator=demodulator def set_fft_size(self,fft_size): #to change this, restart is required self.fft_size=fft_size def set_fft_fps(self,fft_fps): #to change this, restart is required self.fft_fps=fft_fps def fft_block_size(self): return self.samp_rate/self.fft_fps def set_offset_freq(self,offset_freq): self.offset_freq=offset_freq if self.running: self.shift_pipe_file.write("%g\n"%(-float(self.offset_freq)/self.samp_rate)) self.shift_pipe_file.flush() def set_bpf(self,low_cut,high_cut): self.low_cut=low_cut self.high_cut=high_cut if self.running: self.bpf_pipe_file.write( "%g %g\n"%(float(self.low_cut)/self.if_samp_rate(), float(self.high_cut)/self.if_samp_rate()) ) self.bpf_pipe_file.flush() def get_bpf(self): return [self.low_cut, self.high_cut] def mkfifo(self,path): try: os.unlink(path) except: pass os.mkfifo(path) def ddc_transition_bw(self): return self.ddc_transition_bw_rate*(self.if_samp_rate()/float(self.samp_rate)) def start(self): command_base=self.chains[self.demodulator] #create control pipes for csdr pipe_base_path="/tmp/openwebrx_pipe_{myid}_".format(myid=id(self)) self.bpf_pipe = self.shift_pipe = None if "{bpf_pipe}" in command_base: self.bpf_pipe=pipe_base_path+"bpf" self.mkfifo(self.bpf_pipe) if "{shift_pipe}" in command_base: self.shift_pipe=pipe_base_path+"shift" self.mkfifo(self.shift_pipe) #run the command command=command_base.format(bpf_pipe=self.bpf_pipe,shift_pipe=self.shift_pipe,decimation=self.decimation,last_decimation=self.last_decimation,fft_size=self.fft_size,fft_block_size=self.fft_block_size(),bpf_transition_bw=float(self.bpf_transition_bw)/self.if_samp_rate(),ddc_transition_bw=self.ddc_transition_bw()) print "[openwebrx-dsp-plugin:csdr] Command =",command #code.interact(local=locals()) self.process = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True) self.running = True #open control pipes for csdr and send initialization data if self.bpf_pipe != None: self.bpf_pipe_file=open(self.bpf_pipe,"w") self.set_bpf(self.low_cut,self.high_cut) if self.shift_pipe != None: self.shift_pipe_file=open(self.shift_pipe,"w") self.set_offset_freq(self.offset_freq) def read(self,size): return self.process.stdout.read(size) def stop(self): if(self.process!=None):return # returns None while subprocess is running while(self.process.poll()==None): self.process.kill() time.sleep(0.1) os.unlink(self.bpf_pipe) os.unlink(self.shift_pipe) self.running = False def restart(self): self.stop() self.start() def __del__(self): self.stop() del(self.process)