cleaning up and putting much better code in. Step 1 of 2

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@8778 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 87 insertions, 0 deletions

diff --git a/gr-msdd6000/src/python_test/spectrogram.py b/gr-msdd6000/src/python_test/spectrogram.py
new file mode 100644
index 000000000..015dd9105
--- /dev/null
+++ b/gr-msdd6000/src/python_test/spectrogram.py
@@ -0,0 +1,87 @@
+#!/usr/bin/python
+
+fft_bins = 1024;
+stride = 256;
+
+#filename = "output.dat";
+#decim = 4;
+#Fs = (102.4/decim) * 1e6;
+
+
+from gnuradio import gr;
+from Numeric import *;
+import FFT;
+import numpy.fft;
+from numpy import *;
+from pylab import *;
+import sys;
+
+if len(sys.argv) <2: 
+	print "usage:  %s filename <sample_rate_in_MSPS> <stride_samples>"%(sys.argv[0]);
+	sys.exit(-1);
+
+filename = sys.argv[1];
+fs = 0;
+if(len(sys.argv)>2):
+	fs = float(sys.argv[2])*1000000;
+print "opening %s.\n"%(filename);
+
+if(len(sys.argv)>=4):
+	stride = int(sys.argv[3]);
+	print "using stride = %d"%(stride);
+
+tb = gr.top_block();
+src = gr.file_source(gr.sizeof_gr_complex, filename, False)
+sink = gr.vector_sink_c();
+tb.connect(src,sink);
+tb.run();
+
+data = sink.data();
+dataa = array(data);
+datalen = len( data );
+
+time_bins = (datalen - fft_bins) / stride;
+
+print "output vector :: fft_bins = %d, time_bins = %d\n"%(fft_bins,time_bins);
+
+start_idx = 0;
+
+b = numpy.zeros((time_bins, fft_bins), complex);
+l = [];
+
+window = numpy.blackman(fft_bins);
+
+for i in range(0,time_bins):
+	
+	time_chunk = take( dataa, range(start_idx,start_idx + fft_bins), 0);
+	time_chunk = time_chunk * window;
+	fft_chunk = numpy.fft.fftshift(numpy.fft.fft(time_chunk));
+	psd = 10*log10(fft_chunk * conj(fft_chunk)+0.001);
+
+	b[i] = psd.real;
+	l.append( psd.real.tolist() );
+
+	start_idx = start_idx + stride;
+
+#c = array(b, 10);
+
+print b[0];
+c = array(b);
+#l = c.tolist();
+print size(l);
+
+x = range(0,time_bins);
+print size(x);
+y = range(0,fft_bins);
+print size(y);
+
+print size(l);
+
+contourf(l);
+#contourf([x,y], l);
+colorbar();
+show();
+
+#print c[1,1];
+
+