From f6beb407fcdb352c573c3cd1fc01b8f677ce72b8 Mon Sep 17 00:00:00 2001
From: Hannes Matuschek <hmatuschek@gmail.com>
Date: Thu, 24 Jul 2014 00:22:38 +0200
Subject: [PATCH] Fixed waterfall spectrogram.

---
 src/gui/waterfallview.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/gui/waterfallview.cc b/src/gui/waterfallview.cc
index dccdcd1..e36b62b 100644
--- a/src/gui/waterfallview.cc
+++ b/src/gui/waterfallview.cc
@@ -65,7 +65,8 @@ WaterFallView::_onSpectrumUpdated() {
 
   // Draw new spectrum
   for (size_t i=0; i<_N; i++) {
-    double value = 10*log10(_spectrum->spectrum()[i])-10*log10(_N);
+    int idx = (_spectrum->fftSize()/2+i) % _spectrum->fftSize();
+    double value = 10*log10(_spectrum->spectrum()[idx])-10*log10(_N);
     painter.setPen((*_colorMap)(value));
     painter.drawPoint(i, _M-1);
   }