From 970bb33df3e9dfe19d9cae49a95494b7e175644f Mon Sep 17 00:00:00 2001
From: Tom Rondeau
Date: Sat, 20 Oct 2012 17:14:02 -0400
Subject: analog: adding squelch_base_ff and ctcss_squelch_ff to analog.

This addresses the issues of inheriting from both gr_block and another block (squelch_base_ff, in this case).
---
 gr-analog/lib/squelch_base_ff_impl.cc | 140 ++++++++++++++++++++++++++++++++++
 1 file changed, 140 insertions(+)
 create mode 100644 gr-analog/lib/squelch_base_ff_impl.cc

(limited to 'gr-analog/lib/squelch_base_ff_impl.cc')

diff --git a/gr-analog/lib/squelch_base_ff_impl.cc b/gr-analog/lib/squelch_base_ff_impl.cc
new file mode 100644
index 000000000..f9f07d36d
--- /dev/null
+++ b/gr-analog/lib/squelch_base_ff_impl.cc
@@ -0,0 +1,140 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004,2006,2012 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "squelch_base_ff_impl.h"
+#include <gr_io_signature.h>
+
+namespace gr {
+  namespace analog {
+
+    squelch_base_ff_impl::squelch_base_ff_impl(const char *name, int ramp, bool gate)
+      : gr_block(name,
+	         gr_make_io_signature(1, 1, sizeof(float)),
+	         gr_make_io_signature(1, 1, sizeof(float)))
+    {
+      set_ramp(ramp);
+      set_gate(gate);
+      d_state = ST_MUTED;
+      d_envelope = d_ramp ? 0.0 : 1.0;
+      d_ramped = 0;
+    }
+
+    squelch_base_ff_impl::~squelch_base_ff_impl()
+    {
+    }
+
+    int
+    squelch_base_ff_impl::ramp() const
+    {
+      return d_ramp;
+    }
+    
+    void 
+    squelch_base_ff_impl::set_ramp(int ramp)
+    {
+      d_ramp = ramp;
+    }
+    
+    bool 
+    squelch_base_ff_impl::gate() const
+    {
+      return d_gate;
+    }
+
+    void 
+    squelch_base_ff_impl::set_gate(bool gate)
+    {
+      d_gate = gate;
+    }
+    
+    bool 
+    squelch_base_ff_impl::unmuted() const
+    {
+      return (d_state == ST_UNMUTED || d_state == ST_ATTACK);
+    }
+
+    int
+    squelch_base_ff_impl::general_work(int noutput_items,
+				       gr_vector_int &ninput_items,
+				       gr_vector_const_void_star &input_items,
+				       gr_vector_void_star &output_items)
+    {
+      const float *in = (const float *) input_items[0];
+      float *out = (float *) output_items[0];
+
+      int j = 0;
+
+      for(int i = 0; i < noutput_items; i++) {
+	update_state(in[i]);
+
+	// Adjust envelope based on current state
+	switch(d_state) {
+	case ST_MUTED:
+	  if(!mute())
+	    // If not ramping, go straight to unmuted
+	    d_state = d_ramp ? ST_ATTACK : ST_UNMUTED;
+	      break;
+
+	case ST_UNMUTED:
+	  if(mute())
+	    // If not ramping, go straight to muted
+	    d_state = d_ramp ? ST_DECAY : ST_MUTED;
+	      break;
+
+	case ST_ATTACK:
+	  // FIXME: precalculate window for speed
+	  d_envelope = 0.5-std::cos(M_PI*(++d_ramped)/d_ramp)/2.0;
+
+	  // use >= in case d_ramp is set to lower value elsewhere
+	  if(d_ramped >= d_ramp) { 
+	    d_state = ST_UNMUTED;
+	    d_envelope = 1.0;
+	  }
+	  break;
+
+	case ST_DECAY:
+	  // FIXME: precalculate window for speed
+	  d_envelope = 0.5-std::cos(M_PI*(--d_ramped)/d_ramp)/2.0;
+	  if(d_ramped == 0.0)
+	    d_state = ST_MUTED;
+	  break;
+	};
+
+	// If unmuted, copy input times envelope to output
+	// Otherwise, if not gating, copy zero to output
+	if(d_state != ST_MUTED)
+	  out[j++] = in[i]*d_envelope;
+	else
+	  if(!d_gate)
+	    out[j++] = 0.0;
+      }
+
+      consume_each(noutput_items);  // Use all the inputs
+      return j;		        // But only report outputs copied
+    }
+
+  } /* namespace analog */
+} /* namespace gr */
-- 
cgit