X-Git-Url: https://git.gag.com/?a=blobdiff_plain;ds=sidebyside;f=gr-atsc%2Fsrc%2Fpython%2Finterp_short.py;fp=gr-atsc%2Fsrc%2Fpython%2Finterp_short.py;h=11b169b27d6a1486789cb5b29cd4f899ac8b7563;hb=8a9ddbb0675f9bfcc6e03b457fba6c79474a3693;hp=0000000000000000000000000000000000000000;hpb=82d471b9b4a8b389b5da44b19c69c36420828382;p=debian%2Fgnuradio

diff --git a/gr-atsc/src/python/interp_short.py b/gr-atsc/src/python/interp_short.py
new file mode 100755
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+++ b/gr-atsc/src/python/interp_short.py
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+#!/usr/bin/env /usr/bin/python
+#
+# Copyright 2004 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+# 
+# GNU Radio 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 General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, USA.
+# 
+# This module starts the atsc processing chain taking the captured
+# off-air signal created with:
+#
+#  usrp_rx_cfile.py -R <side with tuner, a or b>
+#                   -d 10     set decimation to get signal at 6.4e6 rate
+#                   -f <center of tv signal channel freq>
+#                   -g <appropriate gain for best signal / noise>
+#                   -s output shorts
+#
+# All this module does is multiply the sample rate by 3, from 6.4e6 to
+# 19.2e6 complex samples / sec, then lowpass filter with a cutoff of 3.2MHz
+# and a transition band width of .5MHz.  Center of the tv channels is
+# then at 0 with edges at -3.2MHz and 3.2MHz.
+
+from gnuradio import gr
+import sys, os
+
+def graph (args):
+
+    print os.getpid()
+
+    nargs = len (args)
+    if nargs == 1:
+	infile = args[0]
+    else:
+	sys.stderr.write('usage: interp.py input_file\n')
+	sys.exit (1)
+
+    tb = gr.top_block ()
+
+    srcf = gr.file_source (gr.sizeof_short,infile)
+    s2ss = gr.stream_to_streams(gr.sizeof_short,2)
+    s2f1 = gr.short_to_float()
+    s2f2 = gr.short_to_float()
+    src0 = gr.float_to_complex()
+
+
+    lp_coeffs = gr.firdes.low_pass ( 3, 19.2e6, 3.2e6, .5e6, gr.firdes.WIN_HAMMING )
+    lp = gr.interp_fir_filter_ccf ( 3, lp_coeffs )
+
+    file = gr.file_sink(gr.sizeof_gr_complex,"/tmp/atsc_pipe_1")
+
+    tb.connect( srcf, s2ss )
+    tb.connect( (s2ss, 0), s2f1, (src0,0) )
+    tb.connect( (s2ss, 1), s2f2, (src0,1) )
+    tb.connect( src0, lp, file)
+
+    tb.start()
+    raw_input ('Head End: Press Enter to stop')
+    tb.stop()
+
+if __name__ == '__main__':
+    graph (sys.argv[1:])
+
+