From ba71089affdb9e14fad141bbf6cd27ad6e939692 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Mon, 9 May 2016 01:26:39 +0200
Subject: [PATCH] DSD demod DV serial support revised audio processing

---
 sdrbase/dsp/dspengine.cpp      |  1 +
 sdrbase/dsp/dvserialworker.cpp | 57 ++++++++++++++++++++++++++++++++--
 sdrbase/dsp/dvserialworker.h   | 15 ++++++++-
 3 files changed, 69 insertions(+), 4 deletions(-)

diff --git a/sdrbase/dsp/dspengine.cpp b/sdrbase/dsp/dspengine.cpp
index abdde474a..70994cb58 100644
--- a/sdrbase/dsp/dspengine.cpp
+++ b/sdrbase/dsp/dspengine.cpp
@@ -23,6 +23,7 @@ DSPEngine::DSPEngine() :
 	m_audioSampleRate(48000) // Use default output device at 48 kHz
 {
 	m_deviceEngine = new DSPDeviceEngine();
+	m_dvSerialSupport = false;
 }
 
 DSPEngine::~DSPEngine()
diff --git a/sdrbase/dsp/dvserialworker.cpp b/sdrbase/dsp/dvserialworker.cpp
index db70e53b9..ec99a8d04 100644
--- a/sdrbase/dsp/dvserialworker.cpp
+++ b/sdrbase/dsp/dvserialworker.cpp
@@ -27,8 +27,11 @@ DVSerialWorker::DVSerialWorker() :
     m_running(false),
     m_currentGainIn(0),
     m_currentGainOut(0),
-    m_upsamplerLastValue(0)
+    m_upsamplerLastValue(0),
+    m_phase(0)
 {
+    m_audioBuffer.resize(1<<14);
+    m_audioBufferFill = 0;
 }
 
 DVSerialWorker::~DVSerialWorker()
@@ -77,8 +80,9 @@ void DVSerialWorker::handleInputMessages()
 
             if (m_dvController.decode(m_dvAudioSamples, decodeMsg->getMbeFrame(), decodeMsg->getMbeRate(), dBVolume))
             {
-                upsample6(m_dvAudioSamples, m_audioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE);
-                decodeMsg->getAudioFifo()->write((const quint8 *) m_audioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE * 6, 10);
+                upsample6(m_dvAudioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE, decodeMsg->getAudioFifo());
+//                upsample6(m_dvAudioSamples, m_audioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE);
+//                decodeMsg->getAudioFifo()->write((const quint8 *) m_audioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE * 6, 10);
             }
         }
 
@@ -86,6 +90,38 @@ void DVSerialWorker::handleInputMessages()
     }
 }
 
+void DVSerialWorker::upsample6(short *in, int nbSamplesIn, AudioFifo *audioFifo)
+{
+    for (int i = 0; i < nbSamplesIn; i++)
+    {
+        int cur = (int) in[i];
+        int prev = (int) m_upsamplerLastValue;
+        qint16 upsample;
+
+        for (int j = 1; j < 7; j++)
+        {
+            upsample = (qint16) ((cur*i + prev*(6-i)) / 6);
+            m_audioBuffer[m_audioBufferFill].l = upsample;
+            m_audioBuffer[m_audioBufferFill].r = upsample;
+            ++m_audioBufferFill;
+
+            if (m_audioBufferFill >= m_audioBuffer.size())
+            {
+                uint res = audioFifo->write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 10);
+
+                if (res != m_audioBufferFill)
+                {
+                    qDebug("DVSerialWorker::upsample6: %u/%u audio samples written", res, m_audioBufferFill);
+                }
+
+                m_audioBufferFill = 0;
+            }
+        }
+
+        m_upsamplerLastValue = in[i];
+    }
+}
+
 void DVSerialWorker::upsample6(short *in, short *out, int nbSamplesIn)
 {
     for (int i = 0; i < nbSamplesIn; i++)
@@ -94,6 +130,21 @@ void DVSerialWorker::upsample6(short *in, short *out, int nbSamplesIn)
         int prev = (int) m_upsamplerLastValue;
         short up;
 
+//        for (int j = 0; j < 6; j++)
+//        {
+//            up = 32768.0f * cos(m_phase);
+//            *out = up;
+//            out ++;
+//            *out = up;
+//            out ++;
+//            m_phase += M_PI / 6.0;
+//        }
+//
+//        if ((i % 2) == 1)
+//        {
+//            m_phase = 0.0f;
+//        }
+
         up = (cur*1 + prev*5) / 6;
         *out = up;
         out++;
diff --git a/sdrbase/dsp/dvserialworker.h b/sdrbase/dsp/dvserialworker.h
index c6be12a3e..e3f0419f8 100644
--- a/sdrbase/dsp/dvserialworker.h
+++ b/sdrbase/dsp/dvserialworker.h
@@ -21,6 +21,8 @@
 #include <QObject>
 #include <QDebug>
 
+#include <vector>
+
 #include "dvcontroller.h"
 #include "util/message.h"
 #include "util/syncmessenger.h"
@@ -97,15 +99,26 @@ public slots:
     void handleInputMessages();
 
 private:
+    struct AudioSample {
+        qint16 l;
+        qint16 r;
+    };
+
+    typedef std::vector<AudioSample> AudioVector;
+
     void upsample6(short *in, short *out, int nbSamplesIn);
+    void upsample6(short *in, int nbSamplesIn, AudioFifo *audioFifo);
 
     SerialDV::DVController m_dvController;
     bool m_running;
     int m_currentGainIn;
     int m_currentGainOut;
     short m_dvAudioSamples[SerialDV::MBE_AUDIO_BLOCK_SIZE];
-    short m_audioSamples[SerialDV::MBE_AUDIO_BLOCK_SIZE * 6 * 2]; // upsample to 48k and duplicate channel
+    //short m_audioSamples[SerialDV::MBE_AUDIO_BLOCK_SIZE * 6 * 2]; // upsample to 48k and duplicate channel
+    AudioVector m_audioBuffer;
+    uint m_audioBufferFill;
     short m_upsamplerLastValue;
+    float m_phase;
 };
 
 #endif /* SDRBASE_DSP_DVSERIALWORKER_H_ */