From e5b120311d49d4c8db1f99f2af35aba258c6d5e3 Mon Sep 17 00:00:00 2001
From: Jakob Ketterl <jakob.ketterl@gmx.de>
Date: Mon, 13 Sep 2021 16:58:02 +0200
Subject: [PATCH] get freedv back by modeling a corresponding module and chain

---
 csdr/chain/freedv.py | 28 ++++++++++++++++++++++++++++
 owrx/dsp.py          |  3 +++
 owrx/freedv.py       | 13 +++++++++++++
 3 files changed, 44 insertions(+)
 create mode 100644 csdr/chain/freedv.py
 create mode 100644 owrx/freedv.py

diff --git a/csdr/chain/freedv.py b/csdr/chain/freedv.py
new file mode 100644
index 0000000..d3f2730
--- /dev/null
+++ b/csdr/chain/freedv.py
@@ -0,0 +1,28 @@
+from csdr.chain.demodulator import BaseDemodulatorChain, FixedIfSampleRateChain, FixedAudioRateChain
+from owrx.freedv import FreeDVModule
+from pycsdr.modules import RealPart, Agc, Convert
+from pycsdr.types import Format
+
+
+class FreeDV(BaseDemodulatorChain, FixedIfSampleRateChain, FixedAudioRateChain):
+    def __init__(self):
+        agc = Agc(Format.SHORT)
+        agc.setMaxGain(30)
+        agc.setInitialGain(3)
+        workers = [
+            RealPart(),
+            Agc(Format.FLOAT),
+            Convert(Format.FLOAT, Format.SHORT),
+            FreeDVModule(),
+            agc,
+        ]
+        super().__init__(workers)
+
+    def getFixedIfSampleRate(self) -> int:
+        return 8000
+
+    def getFixedAudioRate(self) -> int:
+        return 8000
+
+    def supportsSquelch(self) -> bool:
+        return False
diff --git a/owrx/dsp.py b/owrx/dsp.py
index 1b5856f..af4ccd7 100644
--- a/owrx/dsp.py
+++ b/owrx/dsp.py
@@ -12,6 +12,7 @@ from csdr.chain.clientaudio import ClientAudioChain
 from csdr.chain.analog import NFm, WFm, Am, Ssb
 from csdr.chain.digiham import DigihamChain, Dmr, Dstar, Nxdn, Ysf
 from csdr.chain.m17 import M17Chain
+from csdr.chain.freedv import FreeDV
 from csdr.chain.drm import Drm
 from csdr.chain.fft import FftChain
 from csdr.chain.digimodes import AudioChopperDemodulator, PacketDemodulator, PocsagDemodulator
@@ -452,6 +453,8 @@ class DspManager(Output, SdrSourceEventClient):
             return M17Chain()
         elif demod == "drm":
             return Drm()
+        elif demod == "freedv":
+            return FreeDV()
 
     def setDemodulator(self, mod):
         demodulator = self._getDemodulator(mod)
diff --git a/owrx/freedv.py b/owrx/freedv.py
new file mode 100644
index 0000000..2c1014f
--- /dev/null
+++ b/owrx/freedv.py
@@ -0,0 +1,13 @@
+from pycsdr.types import Format
+from csdr.module import PopenModule
+
+
+class FreeDVModule(PopenModule):
+    def getInputFormat(self) -> Format:
+        return Format.SHORT
+
+    def getOutputFormat(self) -> Format:
+        return Format.SHORT
+
+    def getCommand(self):
+        return ["freedv_rx", "1600", "-", "-"]