initial commit

plugins/dsp/csdr/plugin.py

@@ -0,0 +1,135 @@
+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 = 300 #Hz, and this is a constant
+		self.running = False
+		chain_begin="nc localhost 4951 | csdr convert_u8_f | csdr shift_addition_cc --fifo {shift_pipe} | csdr fir_decimate_cc {decimation} 0.005 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 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())
+		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)
+