From a66afffd9ed9078dbb1ea0e556916d90998b8218 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Mon, 25 Feb 2019 02:29:59 +0100
Subject: [PATCH] FreeDV demod: initialize FreeDV stuff

---
 plugins/channelrx/demodfreedv/CMakeLists.txt  |  3 +
 plugins/channelrx/demodfreedv/freedvdemod.cpp | 98 +++++++++++++++++++
 plugins/channelrx/demodfreedv/freedvdemod.h   | 13 +++
 3 files changed, 114 insertions(+)

diff --git a/plugins/channelrx/demodfreedv/CMakeLists.txt b/plugins/channelrx/demodfreedv/CMakeLists.txt
index 4b41d26ce..059071e2d 100644
--- a/plugins/channelrx/demodfreedv/CMakeLists.txt
+++ b/plugins/channelrx/demodfreedv/CMakeLists.txt
@@ -24,6 +24,7 @@ include_directories(
 	.
 	${CMAKE_CURRENT_BINARY_DIR}
     ${CMAKE_SOURCE_DIR}/swagger/sdrangel/code/qt5/client	
+    ${CODEC2_INCLUDE_DIR}
 )
 
 add_definitions(${QT_DEFINITIONS})
@@ -42,6 +43,8 @@ target_link_libraries(demodfreedv
 	${QT_LIBRARIES}
 	sdrbase
 	sdrgui
+	swagger
+	${CODEC2_LIBRARIES}
 )
 
 target_link_libraries(demodfreedv Qt5::Core Qt5::Widgets)
diff --git a/plugins/channelrx/demodfreedv/freedvdemod.cpp b/plugins/channelrx/demodfreedv/freedvdemod.cpp
index 1eaf7fc81..75235b394 100644
--- a/plugins/channelrx/demodfreedv/freedvdemod.cpp
+++ b/plugins/channelrx/demodfreedv/freedvdemod.cpp
@@ -22,6 +22,8 @@
 #include <QNetworkReply>
 #include <QBuffer>
 
+#include "codec2/freedv_api.h"
+
 #include "SWGChannelSettings.h"
 #include "SWGFreeDVDemodSettings.h"
 #include "SWGChannelReport.h"
@@ -59,6 +61,14 @@ FreeDVDemod::FreeDVDemod(DeviceSourceAPI *deviceAPI) :
         m_sampleSink(0),
         m_audioFifo(24000),
         m_modemSampleRate(48000),
+        m_freeDV(0),
+        m_nSpeechSamples(0),
+        m_nMaxModemSamples(0),
+        m_iSpeech(0),
+        m_iModem(0),
+        m_speechOut(0),
+        m_modIn(0),
+        m_scaleFactor(SDR_RX_SCALEF),
         m_settingsMutex(QMutex::Recursive)
 {
 	setObjectName(m_channelId);
@@ -413,6 +423,94 @@ void FreeDVDemod::applyFreeDVMode(FreeDVDemodSettings::FreeDVMode mode)
         }
     }
 
+    // FreeDV object
+
+    if (m_freeDV) {
+        freedv_close(m_freeDV);
+    }
+
+    int fdv_mode = -1;
+
+    switch(mode)
+    {
+    case FreeDVDemodSettings::FreeDVMode700D:
+        fdv_mode = FREEDV_MODE_700D;
+        m_scaleFactor = SDR_RX_SCALEF / 3.2f;
+        break;
+    case FreeDVDemodSettings::FreeDVMode800XA:
+        fdv_mode = FREEDV_MODE_800XA;
+        m_scaleFactor = SDR_RX_SCALEF / 8.2f;
+        break;
+    case FreeDVDemodSettings::FreeDVMode1600:
+        fdv_mode = FREEDV_MODE_1600;
+        m_scaleFactor = SDR_RX_SCALEF / 3.2f;
+        break;
+    case FreeDVDemodSettings::FreeDVMode2400A:
+    default:
+        fdv_mode = FREEDV_MODE_2400A;
+        m_scaleFactor = SDR_RX_SCALEF / 8.2f;
+        break;
+    }
+
+    if (fdv_mode == FREEDV_MODE_700D)
+    {
+        struct freedv_advanced adv;
+        adv.interleave_frames = 1;
+        m_freeDV = freedv_open_advanced(fdv_mode, &adv);
+    }
+    else
+    {
+        m_freeDV = freedv_open(fdv_mode);
+    }
+
+    if (m_freeDV)
+    {
+        freedv_set_test_frames(m_freeDV, 0);
+        freedv_set_snr_squelch_thresh(m_freeDV, -100.0);
+        freedv_set_squelch_en(m_freeDV, 0);
+        freedv_set_clip(m_freeDV, 0);
+        freedv_set_tx_bpf(m_freeDV, 1);
+        freedv_set_ext_vco(m_freeDV, 0);
+
+        int nSpeechSamples = freedv_get_n_speech_samples(m_freeDV);
+        int nNomModemSamples = freedv_get_n_max_modem_samples(m_freeDV);
+        int Fs = freedv_get_modem_sample_rate(m_freeDV);
+        int Rs = freedv_get_modem_symbol_rate(m_freeDV);
+
+        if (nSpeechSamples != m_nSpeechSamples)
+        {
+            if (m_speechOut) {
+                delete[] m_speechOut;
+            }
+
+            m_speechOut = new int16_t[m_nSpeechSamples];
+            m_nSpeechSamples = nSpeechSamples;
+        }
+
+        if (nNomModemSamples != m_nMaxModemSamples)
+        {
+            if (m_modIn) {
+                delete[] m_modIn;
+            }
+
+            m_modIn = new int16_t[m_nMaxModemSamples];
+            m_nMaxModemSamples = nNomModemSamples;
+        }
+
+        m_iSpeech = 0;
+        m_iModem = 0;
+        m_nin = freedv_nin(m_freeDV);
+
+        qDebug() << "FreeDVMod::applyFreeDVMode:"
+                << " fdv_mode: " << fdv_mode
+                << " m_modemSampleRate: " << m_modemSampleRate
+                << " Fs: " << Fs
+                << " Rs: " << Rs
+                << " m_nSpeechSamples: " << m_nSpeechSamples
+                << " m_nMaxModemSamples: " << m_nMaxModemSamples
+                << " m_nin: " << m_nin;
+    }
+
     m_settingsMutex.unlock();
 }
 
diff --git a/plugins/channelrx/demodfreedv/freedvdemod.h b/plugins/channelrx/demodfreedv/freedvdemod.h
index 594193421..73bb980e4 100644
--- a/plugins/channelrx/demodfreedv/freedvdemod.h
+++ b/plugins/channelrx/demodfreedv/freedvdemod.h
@@ -29,6 +29,7 @@
 #include "dsp/fftfilt.h"
 #include "dsp/agc.h"
 #include "audio/audiofifo.h"
+#include "audio/audioresampler.h"
 #include "util/message.h"
 #include "util/doublebufferfifo.h"
 
@@ -42,6 +43,7 @@ class QNetworkReply;
 class DeviceSourceAPI;
 class ThreadedBasebandSampleSink;
 class DownChannelizer;
+struct freedv;
 
 class FreeDVDemod : public BasebandSampleSink, public ChannelSinkAPI {
 	Q_OBJECT
@@ -314,6 +316,17 @@ private:
     QNetworkAccessManager *m_networkManager;
     QNetworkRequest m_networkRequest;
 
+    struct freedv *m_freeDV;
+    int m_nSpeechSamples;
+    int m_nMaxModemSamples;
+    int m_nin;
+    int m_iSpeech;
+    int m_iModem;
+    int16_t *m_speechOut;
+    int16_t *m_modIn;
+    float m_scaleFactor; //!< divide by this amount to scale from int16 to float in [-1.0, 1.0] interval
+    AudioResampler m_audioResampler;
+
 	QMutex m_settingsMutex;
 
 	void applyChannelSettings(int inputSampleRate, int inputFrequencyOffset, bool force = false);