refactor

csdr/chain/analog.py

@@ -1,4 +1,4 @@
-from csdr.chain.demodulator import BaseDemodulatorChain
+from csdr.chain.demodulator import BaseDemodulatorChain, FixedIfSampleRateChain, HdAudio
 from pycsdr.modules import AmDemod, DcBlock, FmDemod, Limit, NfmDeemphasis, Agc, WfmDeemphasis, FractionalDecimator, RealPart
 from pycsdr.types import Format, AgcProfile
 
@@ -31,7 +31,7 @@ class NFm(BaseDemodulatorChain):
         super().__init__(workers)
 
 
-class WFm(BaseDemodulatorChain):
+class WFm(BaseDemodulatorChain, FixedIfSampleRateChain, HdAudio):
     def __init__(self, sampleRate: int, tau: float):
         workers = [
             FmDemod(),

csdr/chain/demodulator.py

@@ -1,12 +1,27 @@
 from csdr.chain import Chain
+from abc import ABC, abstractmethod
 
 
 class BaseDemodulatorChain(Chain):
     def getFixedIfSampleRate(self):
         return None
 
-    def getFixedAudioRate(self):
-        return None
-
     def supportsSquelch(self):
         return True
+
+
+class FixedAudioRateChain(ABC):
+    @abstractmethod
+    def getFixedAudioRate(self):
+        pass
+
+
+class FixedIfSampleRateChain(ABC):
+    @abstractmethod
+    def getFixedIfSampleRate(self):
+        return self.fixedIfSampleRate
+
+
+# marker interface
+class HdAudio:
+    pass

csdr/chain/digiham.py

@@ -1,11 +1,11 @@
-from csdr.chain.demodulator import BaseDemodulatorChain
+from csdr.chain.demodulator import BaseDemodulatorChain, FixedAudioRateChain, FixedIfSampleRateChain
 from pycsdr.modules import FmDemod, Agc, Writer
 from pycsdr.types import Format
 from digiham.modules import DstarDecoder, DcBlock, FskDemodulator, GfskDemodulator, DigitalVoiceFilter, MbeSynthesizer, NarrowRrcFilter, NxdnDecoder, DmrDecoder, WideRrcFilter, YsfDecoder
 from digiham.ambe import Modes
 
 
-class DigihamChain(BaseDemodulatorChain):
+class DigihamChain(BaseDemodulatorChain, FixedIfSampleRateChain, FixedAudioRateChain):
     def __init__(self, fskDemodulator, decoder, mbeMode, filter=None, codecserver: str = ""):
         self.decoder = decoder
         if codecserver is None: