usrp_tv_rcv.py

这是用python语言写的一个数字广播的信号处理工具包。利用它

#!/usr/bin/env python
#
# Copyright 2005,2006,2007 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 3, 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., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
# 

"""
Realtime capture and display of analog Tv stations.
Can also use a file as source or sink
When you use an output file you can show the results frame-by-frame using ImageMagick
When you want to use the realtime sdl display window you must first install gr-video-sdl (is in gnuradio cvs).
When you use a file source, in stead of the usrp, make sure you capture interleaved shorts.
(Use usrp_rx_file.py, or use usrp_rx_cfile.py --output-shorts if you have a recent enough usrp_rx_cfile.py)
There is no synchronisation yet. The sync blocks are in development but not yet in cvs.

"""
from gnuradio import gr, gru, eng_notation, optfir
try:
  from gnuradio import video_sdl
except:
  print "FYI: gr-video-sdl is not installed"
  print "realtime SDL video output window will not be available"
from gnuradio import usrp
from gnuradio.eng_option import eng_option
from gnuradio.wxgui import slider, powermate
from gnuradio.wxgui import stdgui2, fftsink2, form
from optparse import OptionParser
from usrpm import usrp_dbid
import sys
import math
import wx

# To debug, insert this in your test code...
#import os
#print 'Blocked waiting for GDB attach (pid = %d)' % (os.getpid(),)
#raw_input ('Press Enter to continue: ')
# remainder of your test code follows...

def pick_subdevice(u):
    """
    The user didn't specify a subdevice on the command line.
    Try for one of these, in order: TV_RX, BASIC_RX, whatever is on side A.

    @return a subdev_spec
    """
    return usrp.pick_subdev(u, (usrp_dbid.TV_RX,
                                usrp_dbid.TV_RX_REV_2,
				usrp_dbid.TV_RX_REV_3,
                                usrp_dbid.BASIC_RX))


class tv_rx_block (stdgui2.std_top_block):
    def __init__(self,frame,panel,vbox,argv):
        stdgui2.std_top_block.__init__ (self,frame,panel,vbox,argv)

        usage="%prog: [options] [input_filename]. \n If you don't specify an input filename the usrp will be used as source\n " \
              "Make sure your input capture file containes interleaved shorts not complex floats"
        parser=OptionParser(option_class=eng_option)
        parser.add_option("-R", "--rx-subdev-spec", type="subdev", default=None,
                          help="select USRP Rx side A or B (default=A)")
        parser.add_option("-d", "--decim", type="int", default=64,
                          help="set fgpa decimation rate to DECIM [default=%default]")
        parser.add_option("-f", "--freq", type="eng_float", default=519.25e6,
                          help="set frequency to FREQ", metavar="FREQ")
        parser.add_option("-g", "--gain", type="eng_float", default=None,
                          help="set gain in dB (default is midpoint)")
        parser.add_option("-c", "--contrast", type="eng_float", default=1.0,
                          help="set contrast (default is 1.0)")
        parser.add_option("-b", "--brightness", type="eng_float", default=0.0,
                          help="set brightness (default is 0)")
        parser.add_option("-8", "--width-8", action="store_true", default=False,
                          help="Enable 8-bit samples across USB")
        parser.add_option("-p", "--pal", action="store_true", default=False,
                          help="PAL video format (this is the default)")
        parser.add_option("-n", "--ntsc", action="store_true", default=False,
                          help="NTSC video format")
        parser.add_option("-o", "--out-filename", type="string", default="sdl",
                          help="For example out_raw_uchar.gray. If you don't specify an output filename you will get a video_sink_sdl realtime output window. You then need to have gr-video-sdl installed)")
        parser.add_option("-r", "--repeat", action="store_false", default=True,
                          help="repeat file in a loop")
        parser.add_option("-N", "--no-hb", action="store_true", default=False,
                          help="don't use halfband filter in usrp")

        (options, args) = parser.parse_args()
        if not ((len(args) == 1) or (len(args) == 0)):
            parser.print_help()
            sys.exit(1)
        
        if len(args) == 1:
          filename = args[0]
        else:
          filename = None

        self.frame = frame
        self.panel = panel
        
        self.contrast = options.contrast
        self.brightness = options.brightness
        self.state = "FREQ"
        self.freq = 0

        # build graph

        self.u=None

        usrp_decim = options.decim # 32

        if not (options.out_filename=="sdl"):
          options.repeat=False

        if not ((filename is None) or (filename=="usrp")):
          self.filesource = gr.file_source(gr.sizeof_short,filename,options.repeat) # file is data source
          self.istoc = gr.interleaved_short_to_complex()
          self.connect(self.filesource,self.istoc)
          adc_rate=64e6
          self.src=self.istoc
          options.gain=0.0
          self.gain=0.0
        else:
          if options.no_hb or (options.decim<8):
            self.fpga_filename="std_4rx_0tx.rbf" #contains 4 Rx paths without halfbands and 0 tx paths
          else:
            self.fpga_filename="std_2rxhb_2tx.rbf" # contains 2 Rx paths with halfband filters and 2 tx paths (the default)
          self.u = usrp.source_c(0,fpga_filename=self.fpga_filename)                    # usrp is data source
          if options.width_8:
              sample_width = 8
              sample_shift = 8
              format = self.u.make_format(sample_width, sample_shift)
              r = self.u.set_format(format)
          adc_rate = self.u.adc_rate()                # 64 MS/s
          self.u.set_decim_rate(usrp_decim)
          if options.rx_subdev_spec is None:
            options.rx_subdev_spec = pick_subdevice(self.u)
          self.u.set_mux(usrp.determine_rx_mux_value(self.u, options.rx_subdev_spec))
          self.subdev = usrp.selected_subdev(self.u, options.rx_subdev_spec)
          print "Using RX d'board %s" % (self.subdev.side_and_name(),)
          if options.gain is None:
            # if no gain was specified, use the mid-point in dB
            g = self.subdev.gain_range()
            options.gain = float(g[0]+g[1])/2
          self.src=self.u

        usrp_rate = adc_rate / usrp_decim           # 320 kS/s

        f2uc=gr.float_to_uchar()
        # sdl window as final sink
        if not (options.pal or options.ntsc):
          options.pal=True #set default to PAL
        if options.pal:
          lines_per_frame=625.0
          frames_per_sec=25.0
          show_width=768
        elif options.ntsc:
          lines_per_frame=525.0
          frames_per_sec=29.97002997
          show_width=640
        width=int(usrp_rate/(lines_per_frame*frames_per_sec))
        height=int(lines_per_frame)

        if (options.out_filename=="sdl"):
          #Here comes the tv screen, you have to build and install gr-video-sdl for this (subproject of gnuradio, only in cvs for now)
          try:
            video_sink = video_sdl.sink_uc ( frames_per_sec, width, height,0,show_width,height)
          except:
            print "gr-video-sdl is not installed"
            print "realtime \"sdl\" video output window is not available"
            raise SystemExit, 1
          self.dst=video_sink
        else:
          print "You can use the imagemagick display tool to show the resulting imagesequence"
          print "use the following line to show the demodulated TV-signal:"
          print "display -depth 8 -size " +str(width)+ "x" + str(height) + " gray:" + options.out_filename
          print "(Use the spacebar to advance to next frames)" 
          options.repeat=False
          file_sink=gr.file_sink(gr.sizeof_char, options.out_filename)
          self.dst =file_sink 

        self.agc=gr.agc_cc(1e-7,1.0,1.0) #1e-7
        self.am_demod = gr.complex_to_mag ()
        self.set_blacklevel=gr.add_const_ff(0.0)
        self.invert_and_scale = gr.multiply_const_ff (0.0) #-self.contrast *128.0*255.0/(200.0)

        # now wire it all together
        #sample_rate=options.width*options.height*options.framerate

        process_type='do_no_sync'
        if process_type=='do_no_sync':
          self.connect (self.src, self.agc,self.am_demod,self.invert_and_scale, self.set_blacklevel,f2uc,self.dst)
        elif process_type=='do_tv_sync_adv':
          #defaults: gr.tv_sync_adv (double sampling_freq, unsigned int tv_format,bool output_active_video_only=false, bool do_invert=false, double wanted_black_level=0.0, double wanted_white_level=255.0, double avg_alpha=0.1, double initial_gain=1.0, double initial_offset=0.0,bool debug=false)
          self.tv_sync_adv=gr.tv_sync_adv(usrp_rate,0,False,False,0.0,255.0,0.01,1.0,0.0,False) #note, this block is not yet in cvs
          self.connect (self.src, self.am_demod,self.invert_and_scale,self.tv_sync_adv,s2f,f2uc,self.dst)