From 8050266b2808c27da603c7253df66610b470a4f9 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Sun, 20 May 2018 19:41:36 +0200
Subject: [PATCH] Channel analyzer NG: autocorrelation corrections (1)

---
 debian/changelog                              |  2 +-
 .../chanalyzerng/chanalyzernggui.cpp          |  1 +
 sdrbase/dsp/fftcorr.cpp                       | 24 ++++---------------
 sdrbase/dsp/fftcorr.h                         |  3 ---
 4 files changed, 7 insertions(+), 23 deletions(-)

diff --git a/debian/changelog b/debian/changelog
index 3e95d948d..f5dbacd38 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,6 @@
 sdrangel (3.14.7-1) unstable; urgency=medium
 
-  * ChanelAnalyzerNG: added PLL option
+  * ChanelAnalyzerNG: added PLL option and source selection with auto correlation
   * RTL-SDR: fixed inf/sup decimators
   * AM demod: syncrhronous AM detection option
 
diff --git a/plugins/channelrx/chanalyzerng/chanalyzernggui.cpp b/plugins/channelrx/chanalyzerng/chanalyzernggui.cpp
index bb7ce2a5f..4be9fb1af 100644
--- a/plugins/channelrx/chanalyzerng/chanalyzernggui.cpp
+++ b/plugins/channelrx/chanalyzerng/chanalyzernggui.cpp
@@ -113,6 +113,7 @@ void ChannelAnalyzerNGGUI::displaySettings()
     ui->deltaFrequency->setValue(m_settings.m_frequency);
     ui->spanLog2->setCurrentIndex(m_settings.m_spanLog2);
     displayPLLSettings();
+    ui->signalSelect->setCurrentIndex((int) m_settings.m_inputType);
 
     blockApplySettings(false);
 }
diff --git a/sdrbase/dsp/fftcorr.cpp b/sdrbase/dsp/fftcorr.cpp
index d82b5d423..5be2c3c9b 100644
--- a/sdrbase/dsp/fftcorr.cpp
+++ b/sdrbase/dsp/fftcorr.cpp
@@ -27,7 +27,6 @@
 
 void fftcorr::init_fft()
 {
-    flen2   = flen >> 1;
     fftA = new g_fft<float>(flen);
     fftB = new g_fft<float>(flen);
 
@@ -35,20 +34,16 @@ void fftcorr::init_fft()
     dataB   = new cmplx[flen];
     dataBj  = new cmplx[flen];
     dataP   = new cmplx[flen];
-    output  = new cmplx[flen2];
-    ovlbuf  = new cmplx[flen2];
 
     std::fill(dataA, dataA+flen, 0);
     std::fill(dataB, dataB+flen, 0);
-    std::fill(output, output+flen2, 0);
-    std::fill(ovlbuf, ovlbuf+flen2, 0);
 
     inptrA = 0;
     inptrB = 0;
     outptr = 0;
 }
 
-fftcorr::fftcorr(int len) : flen(len), flen2(len>>1)
+fftcorr::fftcorr(int len) : flen(len)
 {
     init_fft();
 }
@@ -61,8 +56,6 @@ fftcorr::~fftcorr()
     delete[] dataB;
     delete[] dataBj;
     delete[] dataP;
-    delete[] output;
-    delete[] ovlbuf;
 }
 
 int fftcorr::run(const cmplx& inA, const cmplx* inB, cmplx **out)
@@ -73,7 +66,7 @@ int fftcorr::run(const cmplx& inA, const cmplx* inB, cmplx **out)
         dataB[inptrB++] = *inB;
     }
 
-    if (inptrA < flen2) {
+    if (inptrA < flen) {
         return 0;
     }
 
@@ -90,15 +83,8 @@ int fftcorr::run(const cmplx& inA, const cmplx* inB, cmplx **out)
     }
 
     std::transform(dataA, dataA+flen, dataBj, dataP, [](const cmplx& a, const cmplx& b) -> cmplx { return a*b; });
-
     fftA->InverseComplexFFT(dataP);
 
-    for (int i = 0; i < flen2; i++)
-    {
-        output[i] = ovlbuf[i] + dataP[i];
-        ovlbuf[i] = dataP[flen2 + i];
-    }
-
     std::fill(dataA, dataA+flen, 0);
     inptrA = 0;
 
@@ -108,8 +94,8 @@ int fftcorr::run(const cmplx& inA, const cmplx* inB, cmplx **out)
         inptrB = 0;
     }
 
-    *out = output;
-    return flen2;
+    *out = dataP;
+    return flen;
 }
 
 const fftcorr::cmplx& fftcorr::run(const cmplx& inA, const cmplx* inB)
@@ -120,5 +106,5 @@ const fftcorr::cmplx& fftcorr::run(const cmplx& inA, const cmplx* inB)
         outptr = 0;
     }
 
-    return output[outptr++];
+    return dataP[outptr++];
 }
diff --git a/sdrbase/dsp/fftcorr.h b/sdrbase/dsp/fftcorr.h
index 233d4a745..9da7419e6 100644
--- a/sdrbase/dsp/fftcorr.h
+++ b/sdrbase/dsp/fftcorr.h
@@ -41,15 +41,12 @@ public:
 private:
     void init_fft();
     int flen;  //!< FFT length
-    int flen2; //!< half FFT length
     g_fft<float> *fftA;
     g_fft<float> *fftB;
     cmplx *dataA;  // from A input
     cmplx *dataB;  // from B input
     cmplx *dataBj; // conjugate of B
     cmplx *dataP;  // product of A with conjugate of B
-    cmplx *ovlbuf;
-    cmplx *output;
     int inptrA;
     int inptrB;
     int outptr;