Merge branch 'develop' into pycsdr

csdr/csdr.py

@@ -4,7 +4,7 @@ OpenWebRX csdr plugin: do the signal processing with csdr
     This file is part of OpenWebRX,
     an open-source SDR receiver software with a web UI.
     Copyright (c) 2013-2015 by Andras Retzler <randras@sdr.hu>
-    Copyright (c) 2019-2020 by Jakob Ketterl <dd5jfk@darc.de>
+    Copyright (c) 2019-2021 by Jakob Ketterl <dd5jfk@darc.de>
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU Affero General Public License as
@@ -211,10 +211,7 @@ class dsp(object):
                 "csdr limit_ff",
             ]
             chain += last_decimation_block
-            chain += [
-                "csdr deemphasis_wfm_ff {audio_rate} {wfm_deemphasis_tau}",
-                "csdr convert_f_s16"
-            ]
+            chain += ["csdr deemphasis_wfm_ff {audio_rate} {wfm_deemphasis_tau}", "csdr convert_f_s16"]
         elif self.isDigitalVoice(which):
             chain += ["csdr fmdemod_quadri_cf"]
             chain += last_decimation_block
@@ -473,7 +470,9 @@ class dsp(object):
     def set_secondary_offset_freq(self, value):
         self.secondary_offset_freq = value
         if self.secondary_processes_running and self.has_pipe("secondary_shift_pipe"):
-            self.pipes["secondary_shift_pipe"].write("%g\n" % (-float(self.secondary_offset_freq) / self.if_samp_rate()))
+            self.pipes["secondary_shift_pipe"].write(
+                "%g\n" % (-float(self.secondary_offset_freq) / self.if_samp_rate())
+            )
 
     def stop_secondary_demodulator(self):
         if not self.secondary_processes_running:
@@ -548,25 +547,20 @@ class dsp(object):
                 self.restart()
 
     def calculate_decimation(self):
-        (self.decimation, self.last_decimation, _) = self.get_decimation(self.samp_rate, self.get_audio_rate())
+        (self.decimation, self.last_decimation) = self.get_decimation(self.samp_rate, self.get_audio_rate())
 
     def get_decimation(self, input_rate, output_rate):
         decimation = 1
-        correction = 1
+        target_rate = output_rate
         # wideband fm has a much higher frequency deviation (75kHz).
         # we cannot cover this if we immediately decimate to the sample rate the audio will have later on, so we need
         # to compensate here.
-        # the factor of 6 is by experimentation only, with a minimum audio rate of 36kHz (enforced by the client)
-        # this allows us to cover at least +/- 108kHz of frequency spectrum (may be higher, but that's the worst case).
-        # the correction factor is automatically compensated for by the secondary decimation stage, which comes
-        # after the demodulator.
-        if self.get_demodulator() == "wfm":
-            correction = 6
-        while input_rate / (decimation + 1) >= output_rate * correction:
+        if self.get_demodulator() == "wfm" and output_rate < 200000:
+            target_rate = 200000
+        while input_rate / (decimation + 1) >= target_rate:
             decimation += 1
         fraction = float(input_rate / decimation) / output_rate
-        intermediate_rate = input_rate / decimation
-        return decimation, fraction, intermediate_rate
+        return decimation, fraction
 
     def if_samp_rate(self):
         return self.samp_rate / self.decimation
@@ -601,7 +595,7 @@ class dsp(object):
             demodulator = self.get_secondary_demodulator()
         return demodulator in ["ft8", "wspr", "jt65", "jt9", "ft4", "fst4", "fst4w"]
 
-    def isJs8(self, demodulator = None):
+    def isJs8(self, demodulator=None):
         if demodulator is None:
             demodulator = self.get_secondary_demodulator()
         return demodulator == "js8"
@@ -712,7 +706,11 @@ class dsp(object):
     def set_squelch_level(self, squelch_level):
         self.squelch_level = squelch_level
         # no squelch required on digital voice modes
-        actual_squelch = -150 if self.isDigitalVoice() or self.isPacket() or self.isPocsag() or self.isFreeDV() else self.squelch_level
+        actual_squelch = (
+            -150
+            if self.isDigitalVoice() or self.isPacket() or self.isPocsag() or self.isFreeDV()
+            else self.squelch_level
+        )
         if self.running:
             self.pipes["squelch_pipe"].write("%g\n" % (self.convertToLinear(actual_squelch)))
 
@@ -887,6 +885,7 @@ class dsp(object):
             self.start_secondary_demodulator()
 
         if self.has_pipe("smeter_pipe"):
+
             def read_smeter():
                 raw = self.pipes["smeter_pipe"].readline()
                 if len(raw) == 0:
@@ -896,6 +895,7 @@ class dsp(object):
 
             self.output.send_output("smeter", read_smeter)
         if self.has_pipe("meta_pipe"):
+
             def read_meta():
                 raw = self.pipes["meta_pipe"].readline()
                 if len(raw) == 0:

csdr/pipe.py

@@ -42,6 +42,7 @@ class Pipe(object):
            immediately here), resulting in empty reads until data is available. This is handled specially in the
            ReadingPipe class.
         """
+
         def opener(path, flags):
             fd = os.open(path, flags | os.O_NONBLOCK)
             os.set_blocking(fd, True)
@@ -88,7 +89,7 @@ class WritingPipe(Pipe):
             except OSError as error:
                 # ENXIO = FIFO has not been opened for reading
                 if error.errno == 6:
-                    time.sleep(.1)
+                    time.sleep(0.1)
                     retries += 1
                 else:
                     raise