From 96b72667b50dfbb33f087f3ef89314d99b4632f7 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Wed, 27 Feb 2019 13:57:38 +0100
Subject: [PATCH] FreeDV demod: collect some statistics

---
 plugins/channelrx/demodfreedv/freedvdemod.cpp | 57 ++++++++++++++++++-
 plugins/channelrx/demodfreedv/freedvdemod.h   | 20 +++++++
 2 files changed, 76 insertions(+), 1 deletion(-)

diff --git a/plugins/channelrx/demodfreedv/freedvdemod.cpp b/plugins/channelrx/demodfreedv/freedvdemod.cpp
index 18790bb36..97cd0bca7 100644
--- a/plugins/channelrx/demodfreedv/freedvdemod.cpp
+++ b/plugins/channelrx/demodfreedv/freedvdemod.cpp
@@ -46,6 +46,54 @@ MESSAGE_CLASS_DEFINITION(FreeDVDemod::MsgConfigureChannelizer, Message)
 const QString FreeDVDemod::m_channelIdURI = "sdrangel.channel.freedvdemod";
 const QString FreeDVDemod::m_channelId = "FreeDVDemod";
 
+FreeDVDemod::FreeDVStats::FreeDVStats()
+{
+    init();
+}
+
+void FreeDVDemod::FreeDVStats::init()
+{
+    m_sync = 0;
+    m_snrEst = -20;
+    m_clockOffset = 0;
+    m_freqOffset = 0;
+    m_syncMetric = 0;
+    m_totalBitErrors = 0;
+    m_lastTotalBitErrors = 0;
+    m_ber = 0;
+    m_frameCount = 0;
+    m_berFrameCount = 0;
+    m_fps = 1;
+}
+
+void FreeDVDemod::FreeDVStats::collect(struct freedv *freeDV)
+{
+    struct MODEM_STATS stats;
+
+    freedv_get_modem_extended_stats(freeDV, &stats);
+    m_totalBitErrors = freedv_get_total_bit_errors(freeDV);
+    m_clockOffset = stats.clock_offset;
+    m_freqOffset = stats.foff;
+    m_syncMetric = stats.sync_metric;
+    m_sync = stats.sync;
+    m_snrEst = stats.snr_est;
+
+    if (m_berFrameCount >= m_fps)
+    {
+        m_ber = m_totalBitErrors - m_lastTotalBitErrors;
+        m_ber = m_ber < 0 ? 0 : m_ber;
+        m_berFrameCount = 0;
+        m_lastTotalBitErrors = m_totalBitErrors;
+    }
+
+    m_berFrameCount++;
+    m_frameCount++;
+
+    qDebug("FreeDVStats::collect: demod sync: %d sync metric: %f demod snr: %3.2f dB  BER: %d clock offset: %f freq offset: %f",
+        m_sync, m_syncMetric, m_snrEst, m_ber, m_clockOffset, m_freqOffset);
+
+}
+
 FreeDVDemod::FreeDVDemod(DeviceSourceAPI *deviceAPI) :
         ChannelSinkAPI(m_channelIdURI),
         m_deviceAPI(deviceAPI),
@@ -324,6 +372,7 @@ void FreeDVDemod::pushSampleToDV(int16_t sample)
     if (m_iModem == m_nin)
     {
         int nout = freedv_rx(m_freeDV, m_speechOut, m_modIn);
+        m_freeDVStats.collect(m_freeDV);
 
         for (int i = 0; i < nout; i++)
         {
@@ -494,6 +543,11 @@ void FreeDVDemod::applyFreeDVMode(FreeDVDemodSettings::FreeDVMode mode)
         int nMaxModemSamples = 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);
+        m_freeDVStats.init();
+
+        if (m_nin > 0) {
+            m_freeDVStats.m_fps = m_modemSampleRate / m_nin;
+        }
 
         if (nSpeechSamples != m_nSpeechSamples)
         {
@@ -526,7 +580,8 @@ void FreeDVDemod::applyFreeDVMode(FreeDVDemodSettings::FreeDVMode mode)
                 << " Rs: " << Rs
                 << " m_nSpeechSamples: " << m_nSpeechSamples
                 << " m_nMaxModemSamples: " << m_nMaxModemSamples
-                << " m_nin: " << m_nin;
+                << " m_nin: " << m_nin
+                << " FPS: " << m_freeDVStats.m_fps;
     }
 
     m_settingsMutex.unlock();
diff --git a/plugins/channelrx/demodfreedv/freedvdemod.h b/plugins/channelrx/demodfreedv/freedvdemod.h
index 2b3f1dbae..ae2f7049d 100644
--- a/plugins/channelrx/demodfreedv/freedvdemod.h
+++ b/plugins/channelrx/demodfreedv/freedvdemod.h
@@ -177,6 +177,25 @@ private:
         double m_magsqPeak;
     };
 
+	struct FreeDVStats
+	{
+		FreeDVStats();
+		void init();
+		void collect(struct freedv *freedv);
+
+		int m_sync;
+		float m_snrEst;
+		float m_clockOffset;
+		float m_freqOffset;
+		float m_syncMetric;
+		int m_totalBitErrors;
+		int m_lastTotalBitErrors;
+		int m_ber; //!< estimated BER (b/s)
+		uint32_t m_frameCount;
+		uint32_t m_berFrameCount; //!< count of frames for BER estimation
+		uint32_t m_fps; //!< frames per second
+	};
+
 	class MsgConfigureFreeDVDemodPrivate : public Message {
 		MESSAGE_CLASS_DECLARATION
 
@@ -326,6 +345,7 @@ private:
     int16_t *m_speechOut;
     int16_t *m_modIn;
     AudioResampler m_audioResampler;
+	FreeDVStats m_freeDVStats;
 
 	QMutex m_settingsMutex;