1 files changed, 131 insertions, 0 deletions
diff --git a/flow/stereofftscope_impl.cc b/flow/stereofftscope_impl.cc
new file mode 100644
index 0000000..59ec05a
--- /dev/null
+++ b/flow/stereofftscope_impl.cc
@@ -0,0 +1,131 @@
+    /*
+
+    Copyright (C) 2000 Stefan Westerfeld
+                       stefan@space.twc.de
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+  
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+   
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+    Boston, MA 02111-1307, USA.
+
+    */
+
+#include "artsflow.h"
+#include "fft.h"
+#include "stdsynthmodule.h"
+#include <math.h>
+#include <iostream>
+
+using namespace std;
+using namespace Arts;
+
+namespace Arts {
+
+class StereoFFTScope_impl : public StereoFFTScope_skel, public StdSynthModule {
+protected:
+	static const unsigned long SAMPLES = 4096;
+	vector<float> _scope;
+	/*
+	 * some gcc versions expose ugly behaviour with virtual inheritance:
+	 * putting window[4096] & inbuffer[4096] here bloats the vtable then,
+	 * and tells you to recompile with -fhuge-objects ... so allocate them
+	 * dynamically
+	 */
+	float *window;
+	float *inbuffer;
+	unsigned long inbufferpos;
+public:
+	void do_fft()
+	{
+		float out_real[SAMPLES],out_img[SAMPLES];
+		arts_fft_float(SAMPLES,0,inbuffer,0,out_real,out_img);
+
+		_scope.clear();
+    	unsigned int i = 3;
+    	unsigned int j = 0;
+    	for(;;) {
+        	float xrange = 0.0;
+        	while(j != i)
+        	{
+            	xrange += (fabs(out_img[j]) + fabs(out_real[j]))/(float)SAMPLES;
+            	j++;
+        	}
+			_scope.push_back(xrange);
+
+        	if(i == SAMPLES/2) return;
+
+            i += i/2;
+            if(i > SAMPLES/2) i = SAMPLES/2;
+    	}
+	}
+	void streamInit()
+	{
+		unsigned long i;
+		for(i=0;i<SAMPLES;i++)
+		{
+			float x = (float)i/(float)SAMPLES; 
+			window[i] = sin(x*M_PI)*sin(x*M_PI);
+			inbuffer[i] = 0;
+		}
+		do_fft();	// initialize so that we never return an empty scope
+	}
+	void streamStart()
+	{
+		inbufferpos = 0;
+	}
+	vector<float> *scope()
+	{
+		return new vector<float>(_scope);
+	}
+	/*
+	  in audio stream inleft, inright;
+	  out audio stream outleft, outright;
+	*/
+	void calculateBlock(unsigned long samples)
+	{
+		unsigned long i;
+		for(i=0;i<samples;i++)
+		{
+			inbuffer[inbufferpos] =
+				(inleft[i] + inright[i])*window[inbufferpos];
+			if(++inbufferpos == SAMPLES)
+			{
+				do_fft();
+				inbufferpos = 0;
+			}
+			/*
+			   monitoring only tasks can't be done with that StereoEffect
+			   interface nicely - copy input to output until there is
+			   something better
+			 */
+			outleft[i] = inleft[i];
+			outright[i] = inright[i];
+		}
+	}
+
+	/* prevent vtable overflows (see above) */
+	StereoFFTScope_impl() {
+		window = new float[SAMPLES];
+		inbuffer = new float[SAMPLES];
+	}
+	~StereoFFTScope_impl() {
+		delete [] window;
+		delete [] inbuffer;
+	}
+};
+
+const unsigned long StereoFFTScope_impl::SAMPLES;
+
+REGISTER_IMPLEMENTATION(StereoFFTScope_impl);
+
+}