bandpass_recorder/bandpass_recorder.py

#!/usr/bin/python
import ctypes
from distutils.version import StrictVersion
import os
import sys
import time

from gnuradio import gr
from PyQt4 import Qt

# Import modules from gnuradio-companion generated files.
from bandpass_recorder_file import bandpass_recorder_file
from bandpass_recorder_gui import bandpass_recorder_gui


if __name__ == '__main__':
  # Checks if libX11 works properly.
  if sys.platform.startswith('linux'):
    try:
      x11 = ctypes.cdll.LoadLibrary('libX11.so')
      x11.XInitThreads()
    except:
      print 'Warning: failed to XInitThreads()'

  # Check and parse arguments.
  if len(sys.argv) != 2:
    print 'usage: ./bandpass_recorder_final.py filename\n'
    sys.exit(1)
  if StrictVersion(Qt.qVersion()) >= StrictVersion('4.5.0'):
    Qt.QApplication.setGraphicsSystem(gr.prefs().get_string('qtgui', 'style', 'raster'))
  qapp = Qt.QApplication(sys.argv)

  # Start the GUI
  gui_block = bandpass_recorder_gui()
  gui_block.start()
  gui_block.show()

  # Define callback behaviour for the gui_block: starts the file_block and begins
  # recording once the gui_block is closed.
  def begin_recording():
    # Retrieve parameters
    gain = gui_block.get_gain()
    freq = gui_block.get_freq()
    width = gui_block.get_width()
    record_time = gui_block.get_record_time() / 1000.0

    # Stop the gui
    gui_block.stop()
    gui_block.wait()

    # Start the file recorder
    file_block = bandpass_recorder_file()
    print 'recording... ({0} seconds)\n'.format(record_time)

    # Set parameters
    file_block.set_gain(gain)
    file_block.set_freq(freq)
    file_block.set_width(width)

    file_block.start()
    # Run the recording for the specified time.
    time.sleep(record_time)

    file_block.stop()
    file_block.wait()

    # Rename output file
    try:
      os.rename('recorder.out', sys.argv[1])
    except OSError as e:
      print '\nOSError [{0}]: {1}'.format(e.errno, e.strerror)
      print 'Recording stored in \'recorder.out\'\n'
  qapp.connect(qapp, Qt.SIGNAL('aboutToQuit()'), begin_recording)
  qapp.exec_()