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Diffstat (limited to 'gr-vocoder/python/cvsd.py')
| -rw-r--r-- | gr-vocoder/python/cvsd.py | 86 |
1 files changed, 0 insertions, 86 deletions
diff --git a/gr-vocoder/python/cvsd.py b/gr-vocoder/python/cvsd.py deleted file mode 100644 index e9b3ee305..000000000 --- a/gr-vocoder/python/cvsd.py +++ /dev/null @@ -1,86 +0,0 @@ -#!/usr/bin/env python -# -# Copyright 2007,2011 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. -# - -from gnuradio import gr -import vocoder_swig - -class cvsd_encode_fb(gr.hier_block2): - ''' - This is a wrapper for the CVSD encoder that performs interpolation and filtering - necessary to work with the vocoding. It converts an incoming float (+-1) to a short, scales - it (to 32000; slightly below the maximum value), interpolates it, and then vocodes it. - - The incoming sampling rate can be anything, though, of course, the higher the sampling rate and the - higher the interpolation rate are, the better the sound quality. - ''' - - def __init__(self, resample=8, bw=0.5): - ''' - When using the CVSD vocoder, appropriate sampling rates are from 8k to 64k with resampling rates - from 1 to 8. A rate of 8k with a resampling rate of 8 provides a good quality signal. - ''' - - gr.hier_block2.__init__(self, "cvsd_encode", - gr.io_signature(1, 1, gr.sizeof_float), # Input signature - gr.io_signature(1, 1, gr.sizeof_char)) # Output signature - - scale_factor = 32000.0 - self.interp = resample - - src_scale = gr.multiply_const_ff(scale_factor) - taps = gr.firdes.low_pass(self.interp, self.interp, bw, 2*bw) - interp = gr.interp_fir_filter_fff(self.interp, taps) - f2s = gr.float_to_short() - enc = vocoder_swig.cvsd_encode_sb() - - self.connect(self, src_scale, interp, f2s, enc, self) - - -class cvsd_decode_bf(gr.hier_block2): - ''' - This is a wrapper for the CVSD decoder that performs decimation and filtering - necessary to work with the vocoding. It converts an incoming CVSD-encoded short to a float, decodes it - to a float, decimates it, and scales it (by 32000; slightly below the maximum value to avoid clipping). - - The sampling rate can be anything, though, of course, the higher the sampling rate and the - higher the interpolation rate are, the better the sound quality. - ''' - - def __init__(self, resample=8, bw=0.5): - ''' - When using the CVSD vocoder, appropriate sampling rates are from 8k to 64k with resampling rates - from 1 to 8. A rate of 8k with a resampling rate of 8 provides a good quality signal. - ''' - gr.hier_block2.__init__(self, "cvsd_decode", - gr.io_signature(1, 1, gr.sizeof_char), # Input signature - gr.io_signature(1, 1, gr.sizeof_float)) # Output signature - - scale_factor = 32000.0 - self.decim = resample - - dec = vocoder_swig.cvsd_decode_bs() - s2f = gr.short_to_float() - taps = gr.firdes.low_pass(1, 1, bw, 2*bw) - decim = gr.fir_filter_fff(self.decim, taps) - sink_scale = gr.multiply_const_ff(1.0/scale_factor) - - self.connect(self, dec, s2f, decim, sink_scale, self) |